Printable Version of Topic

Posted by: Type 47 Mar 15 2023, 03:59 PM

so we put the original 62k engine back in that had not had the distributor removed. Adjusted the valves (again after we put about 10 miles on it) we rebuilt the Webbers and it fired up. We did some timing and tweaking on the carbs.

It ran OK but a little shy of perfect. I replaced the wires and it seemed to improve it but idled a little high around 1,200.

My son came over to work on it the next day, but I wasn't home. All of a sudden, it won't even run.

we swapped distributers (both 009's) with the parts car, then swapped points (adjusted to 0.016). no improvement.

tested spark to all four cylinders. I seems like it's really out of timing but we didn't change it much. (except for the fact that we took the distributor out)

my son says we have spark, too much fuel, and not enough air.

What do we do next?????

Posted by: Superhawk996 Mar 15 2023, 04:15 PM

Not trying to be a jerk but saying you didn’t change much right after mentioning a distributor swap doesn’t make sense.

Timing is 100% dependent on the distributor and its position.

If you’re convinced distributor is installed correctly and plug wires are in proper firing order . . . Statically time the car then see if it starts.

Posted by: Root_Werks Mar 15 2023, 04:20 PM

Don't rule out the basics including yourself as a variable. Swapped a dizzy recently in our Jeep, wouldn't light up, seemed like no spark.....until I realized I determined TDC incorrectly = oops. Quick re-do of static timing and Vroom! Fired right off.

Posted by: Type 47 Mar 15 2023, 04:21 PM

you're not being a jerk...I probably didn't explain properly. 6 weeks ago when we put the engine back in we had not touched the distributor. It ran ok, then we began to dial it in.

Today, we swapped distributor, points, etc. trying to figure out why it went south.

Posted by: Type 47 Mar 15 2023, 04:28 PM

completely.

my son, who is an ASE mechanic, has been racking his brain and is a little frustrated.

If it was just me, that would be another question.

So, if distributor, points were working properly could they go south? Could changing the wires triggered something?

Posted by: Superhawk996 Mar 15 2023, 04:33 PM

Using the parts shotgun approach to troubleshoot has created more variables than you started with when it 1st wouldn’t run.

Start over from scratch - verify everything.

You say you have spark - but it needs to be at the appropriate time. (Set static timing)

If you have spark at the proper time and fuel it will run.

Do you see the accelerator pump shooting fuel? Do you smell excess fuel or have wet spark plugs? Why do you say too much fuel not enough air? That is solved by cranking with the throttle open until it catches if you have the idle jets way out of whack.

Posted by: Superhawk996 Mar 15 2023, 04:36 PM

If you have spark the distributor, points, condenser, etc., didn’t go south.

Posted by: 930cabman Mar 15 2023, 04:38 PM

Is there compression?

Posted by: Superhawk996 Mar 15 2023, 04:41 PM

I ASSUMED . . . Good call

Three things to run:
Fuel
Compression
Spark

Verify everything

Posted by: nditiz1 Mar 15 2023, 05:02 PM

I would put the old distro back in and make sure the wires are correct and the engine is on TDC. Verify actual TDC but popping off 1/2 valve cover to see both rockers rattle.

Make sure when you press the gas pedal you can see all 4 throats get a shot of fuel.

I have to assume compression is enough since it was just running.

Start there first.

Posted by: 930cabman Mar 15 2023, 05:02 PM

Is a cam lobe wiped out? Known history is inconclusive

Posted by: Superhawk996 Mar 15 2023, 05:17 PM

I gotta disagree with the distributor swap. If it sparks it’s working. The parts swapping isn’t helpful and is just adding to the confusion. It should have never been swapped in the 1st place.

I get the idea behind it but it’s just another chance to get it 180 out or to have the drive gear (below the tang) get lifted and dropped back in a tooth off.

In practice if you take a car into the shop - they will not start by swapping distributors to solve a timing or no spark condition. A distributor swap would be the last thing in the list.

Like you - I assumed compression but it really should be checked if there is spark and fuel

Posted by: Aerostatwv Mar 15 2023, 05:21 PM

Sounds like a bad condenser to me.

Posted by: Superhawk996 Mar 15 2023, 05:32 PM

If it’s sparking it isn’t a bad condenser leading to a no start

Posted by: Type 47 Mar 15 2023, 05:54 PM

Yes, a lot of fuel. We pulled the plugs to check the gap and make sure they were dry.

While my son has impressed me assembling this car from the rotisserie, he normally does engine work/timing chains, etc. on 5-10 year old cars.

He is "mr. shotgun" and while he has a great understanding of how things work, working on a car without a dozen computers on it is a challenge at times.

Posted by: nditiz1 Mar 15 2023, 05:54 PM

If the swapped in distro is a known working entity then by all means leave it, but it's adding another mysterious part. I always go back to last known since nothing else was supposedly changed from when it was working last.

Posted by: Type 47 Mar 15 2023, 05:56 PM

yes, good compression. except 3 is a little weak.

will check the shot of fuel to each barrel tomorrow

Posted by: Type 47 Mar 15 2023, 05:57 PM

Yes, we put everything back to where it was before.

Posted by: Superhawk996 Mar 15 2023, 06:12 PM

I don’t fully understand what “back where it was before” means to you.

I’ll reiterate - need to set the static timing. Without engine running based on the exact moment the points open using a multimeter to know when the points open.

Without that set - you’re just guessing that the timing is where it belongs in order to start properly.

Posted by: bossboy302 Mar 15 2023, 06:50 PM

Remember that a 4-stroke engine gets to TDC twice...make sure it is at "Ignition" TDC....watch the rockers to verify intake was last valve to close before TDC.

Posted by: Gatornapper Mar 15 2023, 07:27 PM

Best thing I've ever seen on setting static timing on a Type IV engine.....

https://www.youtube.com/watch?v=Lzmqp38kRk8

HTH,

GN

Posted by: Type 47 Mar 15 2023, 09:47 PM

thanks, we understand. Can't tell you how many times trying to get to TDC I've said "are we on 1 or 3"

Posted by: Type 47 Mar 15 2023, 09:49 PM

back to where it was before I put the new plug wires on

Posted by: Superhawk996 Mar 15 2023, 10:22 PM

What is the static timing set at? Should be about 5-7 degrees BTDC. Have you confirmed this?

Posted by: brant Mar 16 2023, 10:58 AM

no one mentioned the 009
it won't be your lack of start problem...

but once it does start.. that curve will create all kinds of crappy running conditions.

brant

Posted by: Root_Werks Mar 17 2023, 02:11 PM

Make sure to post the solution when you do figure things out. We love stories of "Oh, you mean you need to plug the coil in for it to work?" Makes the rest of us feel in like-minded company.

Posted by: lolkema Mar 18 2023, 06:17 PM

I would start by making 100% sure the distributor is installed correctly and not 180° turned. Remove the valve cover of the #1 cilinder , remove the distributor cap and turn the engine until the rotor is pointing to the #1 spark plug lead. Feel if both rockers of the #1 cilinder have clearance, if not the distributor has rotated 180° during install. Happend to me before and I had the same issues you are seeing. I was sure I installed it correct but if it is off by a few degrees when you push it in the engine, the cam won't engage in the notch untill the notch is rotated 180°.

Posted by: Type 47 Mar 18 2023, 07:03 PM

Yes. I'm looking forward to it.

My son had to go with his step dad to Comic Con in KC, so we will be back at it tomorrow or Monday.

Before he left he yanked these off. Probably so I couldn't mess with it while he was gone.

not sure why plug wire #1 is so tight?

Posted by: second wind Mar 19 2023, 01:26 AM

I have to share....my '73 2.0 had "spark" but car would not start for weeks....turned out the spark was not strong enough to work under compression. My non- Porsche cousin said in two seconds "replace the coil" so I did and car started right up and I haven't looked back. Now I know a spark may exist but may not be there under compression...have since learned that the hot-rod high compression crowd knows this one already.....keep going!!
gg

Posted by: ChrisFoley Mar 19 2023, 03:27 AM

Switch wires 1 and 2 for a better fit.
It is also possible to re-clock the distributor by lifting out the drive gear and rotating it before dropping it back in.

Posted by: 930cabman Mar 19 2023, 05:46 AM

I would plug up the open holes (intake manifolds) asap to keep anything from falling into a cylinder. rag, paper towel, ...

Posted by: Type 47 Mar 19 2023, 04:22 PM

Thanks!

Posted by: nditiz1 Mar 19 2023, 06:14 PM

This seems like a very drastic approach. I don't doubt your son is ASE certified, but I don't like the methodology here.

Facts:
Engine ran - not super, but good enough. You had adjusted the valves and rebuilt the carbs prior.

Was timing correct? Unknown, but good enough to run.

At that time you had Spark, Fuel, Compression.

You replaced aged plug wires - Ran better, but idle wanted to be at 1200. At this point it still ran.

Something happened between when you were not home and the next time you tried to start. Could be a number of things, but you said your son was there. Did he touch something?

Then, you started the shotgun approach to getting it running again. Messed with timing because you put a different distro in. Adjusted points. Possibly some other items. Then you swapped things back to when you first had the problem.

Spark - It was mentioned you have spark. How good did the spark look? Someone commented on a weak spark will show, but may not be enough to get the engine running. The coil should be checked with an Ohm meter to be sure. The wires that are on it now had it running so no continuity issues exist with this new set. Battery is enough to turn the engine over so it should be enough to start unless that sounds week.
Items to do -
Ensure static timing is set
Ensure points gap is correct (.016 if I remember correctly)
Retest the spark is strong

Fuel - This one is easy. You don't even need to have the FP working. If when the throttle is pressed do all 4 jets shoot fuel down the throats, if yes then the system has fuel. The bowls have fuel. As long as before you start you have this then the engine will at least run. This would also mean the issue was not from fuel or fuel delivery as the bowls did not go dry which means the pump is pumping fuel AND you have fuel in the tank

Compression - I think you said this was good. The engine ran so I assume at least enough to have it idle.

This setup is far simpler than FI. Less items to have to check and diagnose. Delving into the spark/timing is where I think you should focus and spend time. Sure could you have plugged idle jets, yes, but it will still run. Throw those carbs back on and get that Spark worked out, just my opinion.

Posted by: Dave_Darling Mar 19 2023, 07:51 PM

That distributor does not look to be in the right position. It looks about 90 degrees off to me... Could be the wires are plugged in wrong, could be the whole distributor body is rotated wrong.

You should triple-quadruple check the distributor position and the plug wire locations.

--DD

Posted by: bobboinski Mar 19 2023, 09:02 PM

Distributor cap looks to be wired wrong.
Or maybe the distributor is rotated 90 degrees or more clockwise.
Or both.
I think your vacuum can should be about where the condenser is in the picture in post #1.
At least that is how it is on my 1.7 and 2.0. Maybe 1.8 is different...Never worked on one.

Posted by: VaccaRabite Mar 19 2023, 09:13 PM

Your dizzy is all sorts of awkward in that picture. It’s either wired wrong or it’s 180 out. Either way, this is the cause of your issue.
Give it some gas and you will blow some impressive fireballs out the tops of your carbs this way. BTDT.

Zach

Posted by: ChrisFoley Mar 20 2023, 04:18 AM

Its easy to tell if you're on one or three by removing the distributor cap to verify that the rotor points at the #1 plug wire position on the cap.

Posted by: bossboy302 Mar 20 2023, 12:07 PM

Yikes...if it 'ran' before, but doesn't now, it has nothing to do with the carbs...leave them alone (for now) and sort the issue.

Posted by: Type 47 Mar 20 2023, 12:48 PM

Son #2 who has done 90% of the work on the car in the last 24 weeks is an ASE mechanic. Problem is they must not spend a lot of course time teaching carbs & tuning on 50 year old cars. He is relying on his basic knowledge of how stuff works.

I don't know what happened when I put the plug wires on an it ran well and then next day I'm gone and shoot from the hip son #2 does something.

We WILL get this resolved today.

with all of the great info everyone has posted we will get it straightened out.

Even though to wires are not buttoned up in the clips, I agree something doesn't look right.

as soon as he gets done at the DMV we will get started again.

BTW: Son #1 lives too far away to help. He is a Gold Meister level factory trained Porsche technician and can take apart a 992 (and put it back together) but is like "what's a carburetor?" He did help me take apart the 914 10 years ago though.

Posted by: Superhawk996 Mar 20 2023, 12:59 PM

Not a dig at your sons.

That statement just about sums up the state of the automotive repair world lately. Failing to teach the basics and focused on OBD codes and swapping parts at random. I see it all the time with friends and family when they attempt to get service.

Lest anyone think I’m picking on mechanics, it’s as bad or worse in the engineering. Lots of book knowledge but can’t tell you how many young engineers I’ve worked with have no clue about how stuff actually works, is manufactured, or can use the generic engineering principles to solve specific problems.

Posted by: 930cabman Mar 20 2023, 04:30 PM

Back in the day it was difficult to find (and keep) a real mechanic. These days it's near impossible to beg, borrow or steal a real mechanic. Being a backyard mechanic for 50+ years(at best) I have had a few victories and a many failures. It's a mindset to understand and diagnose any machine. Personally I like to use Sir Issac Newton's model "put the issue in your brain and wait until it surrenders". Works well for me, best of luck

Posted by: Dustin914 Mar 20 2023, 04:54 PM

we are at TDC...how do we set it to 5-7 degrees BTDC?

Posted by: ChrisFoley Mar 20 2023, 06:35 PM

with a timing light while the engine is running.

Posted by: Superhawk996 Mar 20 2023, 07:24 PM

Not really a solution when the engine won’t start and they have no idea where the timing is set at.

Static timing is set without the engine running - Google is your friend as is the link that was posted previously.

Post #21 from Gatornapper is one way to do it by observing the spark.

I prefer to use a multimeter across the points to know exactly when the points open. The engine is set at 7 degrees BTDC by referencing the timing mark on the fan without the engine running. The distributor is rotated until the points just open as observed on the multimeter. Lock down the distributor firmly enough that it doesn’t rotate inadvertently when cranking.

This will set the timing such that you know where the spark is going to occur when the engine is cranking. Once started, then you can use the timing light to fine tune and to observe the mechanical advance from a 009 distributor.

Posted by: Type 47 Mar 20 2023, 08:23 PM

We did get it running, kind of. So we used a timing light. But i'm not sure how to use it. I was able to hold rpm at 3,500 while it was scoped and the mark was there.

not sure how to related that to a static timing of 7.5 degrees.

engine is still popping and backfiring like it was originally.

it was running so good, getting a little discouraged.

BTW, did the test on the lift plate and all is good!

Posted by: Superhawk996 Mar 20 2023, 08:29 PM

If you have it running and can use the light - disregard the static timing. That was only pertinent when you couldn’t get it started.

Posted by: Superhawk996 Mar 20 2023, 08:35 PM

Now that the carbs have been removed - you’re going to have to work your way back through balancing airflow in each barrel, setting idle mixture, setting idle speed and then synchronizing the two carbs.

Have you done that?

Also what are the Venturi sizes and jets that you’re working with?

Posted by: Type 47 Mar 20 2023, 09:18 PM

Why would we have to do that? Kid took them off...I made him put them back on. Nothing changed except making sure they were good and tight.

Airflow is a final adjustment we were almost there when things went south.

you make it seems so simple. I get the synch'n the carbs, but i'm kind of lost at idle mixture/speed.

Posted by: Type 47 Mar 20 2023, 09:40 PM

Could a valve be stuck and causing chaos? then not sticking and runs fine?

Posted by: Superhawk996 Mar 20 2023, 09:55 PM

Not likely at all

Posted by: Dave_Darling Mar 20 2023, 09:58 PM

Distributor. Check that distributor. Do not f**k with the carbs, do not pass go, do not collect $200. Make sure that the distributor is in the right place. Rotate the engine until both valves on #1 are slack, then check where the distributor rotor is pointing. If it's not pointing at the distributor cap terminal that is connected to the #1 cylinder, it's wrong and the car will have one heck of a time starting.

Verify this first. Then make sure that the plug wires follow the firing order as you go around the distributor: 1-4-3-2. If you get the wires wrong, the car either won't start or will run like s**t.

Static timing is basically done by turning the engine by hand until it is at TDC for #1, and turning the distributor so the points are just opening (or could be just closing; I forget which triggers the spark!). Forget 7 degrees or whatever, setting it to TDC will make it close enough for the car to start.

Verify the spark, make sure your distributor is in the right place, then set the static timing so you're somewhere close. The car should be able to run at that point, unless the fuel or the compression is messed up somehow.

--DD

Posted by: Superhawk996 Mar 20 2023, 10:02 PM

Sorry - not trying to over simplify

However tuning is an iterative process. Airflow affects idle mix, mix affects idle speed, idle speed affects timing (due to centrifugal, mechanical advance on 009), and synch between the two carbs goes right back to affecting airflow.

All the above are interrelated to Venturi and jetting.

It’s anything but simple. But it needs to be worked through in a methodical way with each incremental adjustment becoming smaller.

Since you never got to a stable idle below 1200 rpm per your original post I can only conclude that something was not adjusted properly.

Your most recent post of having popping and backfiring could at a bare minimum be tied to it getting lean as you transition off idle.

Posted by: Superhawk996 Mar 20 2023, 10:04 PM

I sort of assumed you have done this when you said you have it running And had verified timing.

Note: the moment when the points OPEN is when the spark is triggered.

Posted by: brant Mar 21 2023, 07:48 AM

Taking the carbs off will effect the linkage

Having unbalanced carb linkage can causing significant popping and back fire

It’s a systemic that requires each step to be correct

Posted by: Type 47 Mar 21 2023, 09:15 AM

checked the valves, there slack, rotor pointing @#1. checked the wires and replugged them to make sure good contact.

car runs but pops, sputters, and backfires.

Posted by: Type 47 Mar 21 2023, 09:16 AM

we did tighten up the linkage. It may be time to get a better one though.

Posted by: Type 47 Mar 21 2023, 09:26 AM

We did have it idling OK before I replaced the plug wires. I should have mentioned that. I was idling OK but still a slight bit of vibration/shake. When I replaced the wires it ran smoother but idle had move up from about 900 to 1200.

Posted by: nditiz1 Mar 21 2023, 09:29 AM

If the car pops stutters backfires at IDLE here are the things to check:

Idle circuit is dirty - are the carbs clean? Have they been cleaned?
Mixture screws are set too lean - richen them up to see if the popping goes away.
Get the Syncrometer on the throats and see if all 4 are in sync. You don't need linkage at this step.

Timing could be off, but I believe you ran it up to 3500 and set the timing to 27/ the mark on the pulley. If you did, then the timing is correct, no need to touch the timing anymore.

Getting a smooth idle of around 1000-1100 is the key right now. You can worry about smoothness up to 3500 in a later step.

EDIT - Adjust idle speed with the carb idle speed adjusters which will in turn adjust the vac pull so double check they are back in sync. When you want to make the car smooth throughout the RPM band you will need to use the syncrometer to check the vac pull at a few different intervals up to ~3000 rpm. Hold the rpm steady at 1500, check both sides, 2000 check both sides, 2500 check both sides. Each interval should have the same pull which means the linkage is in sync.

EDIT2 - some engines like to idle at a higher RPM then 950. 1200 is a little on the high side I would shoot for between 1000-1100. The best budget linkage is the CSP center pull. You can see it on Zach's latest 2.3 PMB engine.

Posted by: brant Mar 21 2023, 09:58 AM

even a worn out linkage can be balanced... it just won't hold it well over time
balancing the linkage ensures both banks open the butterflies at exactly the same time
and does not create a lean condition (popping) on one bank...

after a good baseline balance is found
then fine tuning can be done with the carb balance screws

Posted by: technicalninja Mar 21 2023, 10:12 AM

I'm not sure if the 914s have a full advance timing mark but most cars don't.

If a standard style mark (usually idle with vac lines removed from dist) is being used and he saw that mark at 3,500 rpm he may still be way off on his timing.
3,500 will usually have almost all of the mechanical advance in and some of the vac adv/retard in.

I am not a 914 timing guru yet but I'd expect that the "timing" would be way the hell out at 3500 rpm if I could see the timing marks in the indicator. I'd expect 25 degrees + of advance at that speed.

Ignition function and timing FIRST. Then setting up fuel, balance airflow, set throttle linkage second.

The linkage has to be adjusted, just being "tight" is not being adjusted.
Replacing linkage before understanding how the linkage is to be adjusted will only further the OPs frustration with this process IMO.

On my 914 we didn't even get feeler gauges out to check points. A dwell meter was used from the start. I had to find my dwell meter as I hadn't used it in 20 years.
It took longer to find that critter than it took to set the points...

Just checked my "tune up" specs tag on my 75 L-jet 1.8. It says timing is to be 7.5 degrees advance at 850 +/- 50 rpm with vacuum hoses to distributor removed...
So the Germans are using a "normal" timing procedure and if he's seeing the marks at 3500rpm he is 25+ degrees RETARDED!
It is completely IMPOSSIBLE to adjust carburators at these timing settings.

The distributor should be twisted toward advance 20+ degrees.

Get it running with a slightly lose distributor clamp and try to twist it either way.
One direction it will get worse and the other it will clean up.

I can set what I call "base" timing with a timing light hooked up to the coil wire and the fuel system disabled. I'd want to see the timing mark in the window without the car running. The coil wire will flash 4 times for 2 revolutions and two of those flashes will be on the marks. two will not but your brain will overlook them and all you will see will be the marks themselves.

Your timing is still WAY out. That has to be addressed first before the carbs are messed with.

If my son had completely removed a pair of ITB carbs before we diagnosed what was wrong with the car I'd kill him.

If he left the intakes wide open, I'd bring him back to life and kill him again...

I don't use rags for closing off open intakes. Had too many sucked into engines when they were turned over by accident, I use the aluminum tape (has the paper covering the sticky side). This stuff doesn't break, and it peels back off nicely when you need to remove it. Nothing gets into intakes.

Posted by: technicalninja Mar 21 2023, 10:17 AM

And here is where my 914 lack of knowledge might be hurting me...

If it really has a timing mark of 27 degrees, then that is a mechanical advance fully in mark and it SHOULD be set at high RPM.

If this is the case my previous post is hogwash...

I was not aware of a high speed mark and I apologize if this is the case...

Posted by: nditiz1 Mar 21 2023, 10:18 AM

Yes please retract your post

Just so we are clear, there are at least 2 ways to set the full advance timing with a timing light at 3500rpm. As the OP did it with the gun having no digital advance OR set to 0 you should see the mark of 27 degrees on the wheel or one you have placed on the wheel (follow the guide on how to create).

The second way is to set your gun to 27 and line it up to the 0 mark on the pulley, both ways will get you the full advance.

He is working with a 009 which has no vac cannister on it. It is crude but works. Be sure to plug any open vac ports on the carbs that could introduce additional unwanted air. The SVDA is one of the best cheap distros you can have with your dual carb setup.

Posted by: technicalninja Mar 21 2023, 10:39 AM

Yep, I'm sorry I may have added to the confusion.

I'll never retract something I post in error. I'll allow my lack of knowledge to be in full view of all.

I will apologize and re-post if I'm wrong, however.

You should notice that I was damn close to what the timing should be at that RPM.

I posted 25+degrees at 3500 rpm. I was 2 degrees off!
I just pulled that number out of my knowledge base in my memory.

Red mark is 27 and 0 mark is TDC.

How did Porsche expect technicians to be able to set timing to 7.5 advance at 850 rpm as my timing sticker states?

I wasn't aware of any timing lights that could do advance back then...

I started doing this stuff professionally (all this means is being paid) in 1982.

Posted by: ClayPerrine Mar 21 2023, 10:48 AM

Just so you know, the 009 is a terrible distributor for a VW Type IV engine. The advance curve is completely wrong for it. IIRC, I don't think you can actually get 27 degrees at 3500 RPM with an 009 without having the base timing really off.


There are 4 things needed to make an internal combustion engine run, and they can be remembered with the acronym "FAST"

Fuel
Air
Spark
Timing


Fuel - you have that and you can adjust the carbs after it is running
Air - the engine is making compression
Spark - you verified that already
Timing - Start with that.

How I do it.
Take out the #1 spark plug. Put in the hose from a compression tester. Using a remote starter button, crank the engine over while keeping your thumb over the end of the compression tester hose. When it blows your thumb off the hose, you are on the compression stroke.

Now turn the engine until the 0 mark is in the timing marks in the fan housing. Make the rotor in the distributor point to the left front of the car. Reinstall the cap and put the wires on. The two plug wires on the right side of the motor connect to the two distributor towers on the right side. The two plug wires on the left side of the motor are crossed, i.e. the front spark plug connects to the rear distributor tower, and the rear spark plug connects to the front distributor tower.

Turn the motor until you have about 8 degrees advance on the timing marks. Then hook a test light to the points wire and hook the other end to the positive battery post. Turn the distributor back and forth until the light just goes out. That sets the static timing.

Hook the points lead back up to the coil and the car should start. You will need to make sure the carbs are properly synced at idle. Once you do that, you can then take the engine to 3500 RPM and check the timing is a 27 degrees.


I hope this helps.

Posted by: Superhawk996 Mar 21 2023, 11:16 AM

1.8L engine has a 7.5 degree timing mark on the impeller.

At this point with so many parts having been swapped mix and match on 914s you’re liable to find a 7.5 degree mark on others including those that may have been added at a rebuild.

As a rough approximation 7 degrees is about 3/4 of the distance between impeller blades.

Posted by: nditiz1 Mar 21 2023, 11:28 AM

009 should have no problem getting to the base. Its curve closely resembles the 034 SVDA. Reason why the SVDA is better is because it eliminates the "flat spot" on acceleration and makes it so you dont need to run super rich to over come it.

Posted by: technicalninja Mar 21 2023, 12:08 PM

Thanks again SH...
My 75 1.8 blower is still in the car. I have a 73 2.0l core I got from Mark Heard completely apart and it does not have the 7.5 indicator etched on it.
I did post that I was not a 914 timing Guru yet...
Guess what, I was RIGHT!
And now I'm a little bit smarter because of this thread.

Posted by: cgnj Mar 21 2023, 01:29 PM

Hi,
You never said what fixed your no start problem. Something did. Care to share?

Carb setup - I have limited Webber experience. I prefer Dellortto. In either case I never open more than one air bypass screw per side.
I generally follow this procedure https://www.aircooled.net/synchronize-dual-vw-carburetors-103/

Posted by: Type 47 Mar 21 2023, 01:53 PM

Carlos,

while we did get the engine fired it's far from fixed. I will be reading your carb instructions next, thanks for posting the link.

Posted by: Type 47 Mar 21 2023, 02:11 PM

thanks for posting this.

Is there any difference between the 1.8 and 2.0?

the pic below is the actual impeller from this engine. It had some broken fins so we swapped it with another one from a spare 2.0. Nothing but the 27 line, no 0, no 7.5 mark.

The impeller we put on it was from GA006291 a late 73' 2.0 I believe. It has the 0 and the 27 mark. I will have to look closely at it, now I know where to look for the black line.

I hear what your saying about "at this point" I do believe this engine is original to this car; both have low production #'s 00696 for the car and GC000243 for the engine.

Then again it had a degree plate on the front of the engine like a bus would have.

Posted by: technicalninja Mar 21 2023, 02:26 PM

Just looked at the link provided for syncing carbs.
Very good into. I have both tools and far. far prefer the snail gauge.

One thing that link didn't provide was what I do now FIRST.

I'll set the throttle stops on the carbs (commonly I was doing 3 two bl side drafts) to have the same openings when you look through the carb when off the car.

I'd back the throttle stops out until the blades actually seated and then chose one carb to be my standard. I'd open the throttle stop approx 1/2 turn from blade closed and then set the others in much the same way.
I'd then hold the carbs and look through the bores with a light source behind the carb,
I'd adjust # 2-3 to have the same width crescent of light coming that will be visible from the light source. On an IDF which has a adjustment between the two bores I'd set this adjustment next.
I'd bolt them on and hook up linkage and adjust the linkage to make all three carbs open at the same time.

Really important to set any mechanical throttle for WFO right from the start. Have someone bury the accelerator hard into the floorboard and verify the carbs can just hit wide open without any undue stress happening in the linkage.
All throttle cables should be adjusted for wide open first!
Most designs will then have the extra play at the beginning of the throttle stroke and you will not be able to damage. bend, or knock your adjustments out by flooring it.

After you have this together make sure the throttles all open at the same time VIA the accelerator pedal. Adjust individual linkages accordingly.

I found adjusting this crap, by eyeball, when the car is not running got 90% of the sync job done and the use of the snail tool was for minor finish up adjusting only.

The above mentioned procedure decreased the time involved for me by 75%.
Sometimes just eyeballing it was dead nut on.
It turned what can be a frustrating job into gravy...

Posted by: Type 47 Mar 21 2023, 02:56 PM

The carbs where taken apart and cleaned enough to install what was in a rebuild kit. They were not completely taken every single piece apart.

by richen them I'm assuming you mean backing the screws out

Posted by: Type 47 Mar 21 2023, 03:00 PM

Yes, all of this helps. Thank you.

Posted by: nditiz1 Mar 21 2023, 06:37 PM

There are definitely different levels of cleaning. Even to go as far as dipping them in Chem dip. The rebuild kit will break the carb down enough to get most areas clean. You need to pay attention to the passages and shoot brake cleaner and compressed air through them.

Did you perform the float adjustment procedure. Very key to setting carbs up?

Ensure you have proper fuel pressure to the carbs (3psi)

Dialing in carbs is not difficult, but it can be time consuming. You also need to make sure the the engine is warm.

Since it will at least idle you already have a base. Pop off the linkage on side so it does not interfere with getting them to idle smoothly. Use the snail gauge to ensure the vac on both L and R are the same. Also ensure the the throats on the same carb are also in sync. The bypass screws should start all the way closed. These screws will be opened to increase the vac on that throat. In the perfect world all throats will be the same as the pull on each cylinder is perfectly matched, but I have yet to encounter this so minor adjustment is always needed.

Now that all 4 carbs are in sync you can use the Idle speed screw to bring the idle to around 1000. When you do this your sync will be off so readjust L and R.

Now you should be running ~1000 and the Land R are in sync. Start turning the mixture screws out from all the way in about 3 turns. Slowly screw it in until the engine starts to stumble. If the idle never drops you could have an issue (dirt) with that throat. The point at which the engine starts to stumble means it is going lean. I usually back the screw out a half turn or quarter depending on the jet size. This will get you close to best lean idle. If the engine is worn the same all 4 mixture screws should be within a quarter to half turn of each other. It is a good practice to perform this step a few times as it could increase you idle. This will make you move the speed screws out to lower idle which will change the mixture. It is a cycle to get everything into a harmonious balance.

If you have made it this far the engine should be pretty smooth. If not you could have any number of issues, dirty carbs, intake leak, exhaust leak.

The last step is to sync the carbs under throttle from linkage. You use the sync gauge again holding different RPM to ensure the L and R are the same. If one side is pulling more then adjust the linkage. You never need to touch mixture, idle speed, or bypass screws.

The last step involves driving, getting a feel, and using a AFR meter to possibly rejet.

Posted by: Rand Mar 21 2023, 07:04 PM

I'd be interested in your explanation of why and how a condenser would cause this.

I'm also curious to know what color the spark is?? (like yellow, or bright blue?)

Posted by: Type 47 Mar 21 2023, 08:13 PM

will follow your tuning advise. I'm hoping this experience is teaching someone some patience and understanding.

BTW, didn't work on the car today. Want to soak all this info in and move forward tomorrow.

Posted by: ChrisFoley Mar 22 2023, 05:23 AM

That red line on your impeller is the 27 degree mark, which is what you want to see with the timing light at 3000-3500 rpm. Actually, a little past that mark, so you are at 28 deg. is even better.

Posted by: bossboy302 Mar 22 2023, 11:40 AM

TYPE 47: you never have explained how you got from "what happened-not running" to "Got it to run".

Even if it still runs poorly, you solved something.........what?

Posted by: Type 47 Mar 22 2023, 02:48 PM

we set the static timing and then cranked it until it fired. We have to keep a hand on the linkage to keep it running. it doesn't idle on it's own yet.

We ran out of time and haven't been able to work on it further.

will update on the progress. when we work on it next, maybe tomorrow or Friday.