Greetings. I am new to the Porsche world and I purchased a 1972 914 1.7 about a month ago. It's a pretty nice car over all, but I think the motor, or part of the motor, might be toast.

When I purchased it, it badly needed a muffler. The knocking noise was harder to notice and sounded more like an exhaust leak over the horrible sound of the lack of a working muffler. The car seemed to run decent even with the poor exhaust and the price was good so I bought it. I just wanted a decent car over all that I could drive around for fun on sunny days before the winter gets here. It came with stainless heat exchangers I installed and I installed a really nice dual muffler from Dave at Triad.

When I fired it up with the new muffler, I really noticed the knocking when I drove it since the all the exhaust leaks were now sealed up and I wasn't wearing ear plugs. At idle it's not too bad, but once I get going, the knocking is very noticeable. It's odd too, because it's not real consistent under power in motion.
To me it sounds like the noise is coming from the #1 cylinder. I think the cylinder is providing no power, because when I take the wire off the cap, there is really no change in performance. (I put a video link of the horrible sound below.)

Any advice on where to go from here would be great. My gut feeling is telling me the motor is going to have to come out. If I'm going to do all that, I might as well put a 2.0 liter in or ????? I'd even settle for just a solid running motor with some minor upgrades to make it a little quicker. Any advice on what route to take on a good used motor would be great. I guess A motor that runs on 4 cylinders would be an upgrade. Thanks for your help, a mildly depressed Sam

http://www.youtube.com/watch?v=a5JhEd7SUH4...re=channel_page Click to view attachmentClick to view attachmentClick to view attachment

Hey Sam,

!!
Before you pull the motor, try and adjust the valves. It may be that the rocker arm has come off. It happens, and makes a clatter and the cylinder won't fire. If thats it, it is a simple fix, and will be very noticable when you go to adjust valves.

After valves are done, do compression test. (valves need to be right, throttle needs to be open). That will tell you if the cylinder is at least building compression.

if you have dropped a valve seat (zero compression on #1 is probably a dropped seat), it is rebuild time. At that point, source a 2.0, or rebuild the 1.7 into a 1911.

Zach

nice to see another PNW teener. and zach pretty much summed it up.

Beg to disagree!

The 1.7 is a rock solid motor. You aren't going to get a significant HP increase by zooming the motor.

BYW - to the owner - welcome to the mayhem! Those wheels are not proper for a '72.
Pat

welcome. Do a valve train check first. Shame the car has lost it's FI

I run a standard 1.7l with D-jet and it's a great little motor... Did 400 miles over the weekend and it ran as sweet as a nut. Yes 170hp would be nice, but it keeps up with modern traffic very easily..

Do you like the sound of the Triad??

I agree with Zach. Maybe roll the pushrods to check if one is bent ?

Huh? I don't get the disagreement. First have to find out if this 1.7 is rock solid or not. It would be great to find a valve train problem that could be fixed without having to tear the motor all the way down. If you do have to rebuild it then choose your build based on the level of performance/economy you want. A 1.7 with FI is a sweet economical package. Carbed with a stock cam, not so much. A strong 2.0+ is a lot more fun.

Those are the most-desired 4-lug wheels. The only way they are improper is if you are being judged on a concourse. The other 99.9% of people will appreciate your Fuchs.

Welcome. Hang in there and cross your bridges one at a time.

Thanks for the help. I'll give it a look and see what's going on under the valve cover. I hope it is fixable. I just want to drive the car for now and use all 4 cylinders.
If the motor does come out; I think something faster will go back in because The car is not completely stock anyway.
Sam

Thanks for the welcome. I'd be happy with the 1.7 if it was running on all 4, but it's not. If it's fixable, it will stay in as is.
There are several things on and in the car that are not stock for the year. I really like those wheels on the car and They are very light too.
Sam

Thanks. I too was sad the fuel injection car was gone, but was happy to see two carbs instead of one. (probably does not need dual carbs)
I was real pleased it has 5 speeds and does great on the freeway even on 3 cylinders. I'm surprised it runs as well as it does even with the malfunction. I know I'll be much more pleased with 4 fully functioning cylinders.

I do like the sound of the Triad and I like how it looks too. I just wish I could hear it with a healthy motor because I think it will sound even better. It's built really well and I'd recommend one if you are looking for louder than stock. It's a good price for the quality.

If you like the wheels, keep them as they are the right offset and look great on that car.

I agree with Zach about checking the valve train first, especially if I hear it right and the knock is not every rotation of the engine, but about every other, which points to the valve train.

Pull the covers, see if everything is in place and the rocker shafts are tight to the heads, that the adjustment screws are in place, and that none of the rockers has enormous play in them.

Then report your finding, including a picture, as it keeps people interested and there will be lots of help.

Certainly, you could have a real engine threatening problem, but let's do the easy stuff first.

Good luck and I hope this helps.

Thanks for the encouragement. I don't know first hand, but I just seem to think a bigger motor would be more fun too. I'm not looking for fuel economy or a quiet ride. I have regular cars for that stuff.

I really like the Fuchs too and was happy they were on the car. If it didn't have them already, I'd go find some and buy them.

Just one more thing of encouragement, that doesn't sound like the "BAD" sounds that I've heard.

Last DE I was in at Watkins Glen, I guy came off the track spewing oil in his recent top end rebuilt 3.2 (911) and that engine was just destroying itself.

We tried to get him to let us push it on the trailer, but he wanted to drive it up.

It was as if we were just throwing hundred dollar bills into the intake for the damage it was doing. Probably was throwing bits of a piston around in there...

he would have saved thousands of dollars if he had just killed the motor while on the track and let the tow truck pull him in.

The worst noise I've ever heard on a motor. I've heard ones like yours before and they survived. Of course, this is all from an youtube clip so...

Hah! I did not even see the youtube clip.

Anyway, that sounds a lot like my motor sounded when the rocker arm backed off the studs. Scared the living daylights out of me at the time. Took about 15 minutes to fix - its just two nuts.

Check your valve train fo-sho! I'm sending you positive waves!




Zach

First things FIRST....BASIC THINGS FIRST...."I pulled the wire out of the distributor cap....and there was no change". (in the dead cylinder). CHECK THE SPARK PLUG WIRE for continuity. (does electricy flow through it, and the spark plug connector , and connector that inserts into the CAP....= good or bad., bad = replace ALL of them. Good = go to spark plug next. remove and inspect, , oiled = missfiring, (can also have gas smell=misfiring). BAD = replace all spark plugs. be sure to gap them properly. Note ; there are replacement spark plug wire sets out there, that are of the suppression type. these are carbon impregnated, coated, (nylon, fabric, or some such). THEY are great for radio static suppression. BUT THEY will break internally. causes obviously, misfires or dead spark plugs. The noise may be from ..THAT particular Piston not being hot and ratteling in the cylinder. After these basic things well...Post.. what you do and discover.

One ADDITIONAL THOUGHT...whenever you purchase any car with a "bad muffler"...just assume the owner is intentionally masking an engine problem. it,s a very old con/trick. you will also find the price is really good almost too good to be true. Pass it by, or FACTOR into the price and value a replacement engine.

valve train
tune up
carbs adjusted

Any update?, Inquiring minds WANT to know!

I'm just getting started right now. Had to work last night until 5am.
Hoping for fixable.

Checked the valves and only a few needed adjusting, but not bad. Everything looked in order under the valve covers. I wanted to check the valves anyway since the car is new to me.
Sure is fun climbing around under a car and always leaving your tools in the wrong place.
Pulled the plug from #1 and it was fouled bad. Ugliest plug I've ever pulled from one of my cars over the past 19 years. I believe the Plug wire was pretty much separated from the (term slips my mind) orange insulator thing that goes onto the plug. I got that sorted out for now. On my way to the parts store for 4 new NGK plugs for now and see how that goes. Import parts are not a common thing in Skagit Valley.
I'll update in a bit on how she runs with some new plugs.

Click to view attachment

Click to view attachment

Click to view attachment

Here's hoping for something as simple as a bad plug/wire. Cheers to a tuneup!

Haha! Zach's brother drives a tank! Good, I'll help fan the positive waves! (good movie man- nice touch~)

Welcome to 914World. A few things, It is fixable- it will ride.
Just a matter of cheap or not as cheap.
Even so, a used 1.7 is just a few hundred and you have a car that 20 grand does not buy. Vintage no less- do not worry.
Your motor is a reliable design shared with the VW van of several years and well proven. Large and tough enough for 3 cyl though this is unhealthy- it can still move alone easily on those 3.
Let's get it right though, the compression, the valves, then deeper as needed. Engine was made to be "easily" pulled with everything as a pack.
Check out the 914 info section and then the tech articles for some specific instructions like removal (when needed-) and others. Smart-simple-happy engineering.
DO not worry at all- fix and ride, no worries -my friend. Together, there is 4x the knowledge to rebuild your speeder 20 different ways. Enjoy! -Jzn

Wow, I have never seen such a fouled plug.

Looks like oil fouling, which makes me think that you are probably looking at a top end rebuild in your near future.

SO, tell us how it runs with the cleaned plug (as that one will give you no spark at all) and then get a good compression test of the whole 4 cylinders.

Good luck and I hope that helped.

It ran the same. #1 cylinder was dead weight. The other plugs were not bad, but they were replaced too just for science.
I have a bad feeling there is zero compression in #1 and the knocking noise is the piston rattling in the cylinder. I've also noticed in the few miles I have driven it, it ate a lot of oil. Probably just flying out the #1 in addition to leaking all over the cardboard.
I'll go make sure it's getting spark (I'm pretty sure it is) now that I'm home from taking the wife out in the boat.
I really like this car too, but this is depressing because I was not looking for a project when I bought it. I just got done with a project and now I just want to drive!!!

Well, the good thing is that you can do a stock top end rebuild in a very short amount of time, and no serious money (unless the head is un-rebuildable).

Sounds like you should do that compression test and then pull the motor and that side head. Sorry to have gotten your hopes up with the possibility of a valve train noise.

Well, I have spark so it's not that. I checked the compression the best I could with an old timey tester and my wife at the key and it read about 135 - 140. So there is compression, but I didn't look up what proper compression is.

I don't think it's getting any fuel. Can this be?? # 2 cylinder is getting fuel just fine.
When I pulled the #1 plug after running it a bit earlier, It was already getting black from unburnt oil and I don't think there was any fuel smell on it.

It has the dual carbs, but I don't really know anything about them. I'm somewhat familiar with SU''s and I'm guessing these are webbers. I'll go check em out a little more.

Well...140 psi does not indicate a blown piston, or dropped seat,or valve. YOU MAY have an easy fix.,,BUT DID YOU REPLACE or absolutely make sure THAT spark plug wire is good. SET spark plug gap to .028 ths. check and recheck that the valve lash is properly set to .006 ths.when you know all this is right do the following......Flash back to maybe its an easy fix...what could have happened is that the P.O. previous owner had a bad plug, it fouled , and that cylinder went dead....but the dumb ass kept driving the car....SO the rings and oil control rings have just gotten "loaded up" with oil, and, with so much oil on the cylinder wall have become "unseated"....get some extra spark plugs.(for the bad cylinder.) DO NOT DRIVE THE CAR. start it and let it idle at a high idle it should be higher IF the plug is firing, as compared to before...do not let it run with a misfiring plug. if its firing you should detect blue smoke from the exhaust..white if it has synthetic oil. ( thats why you got spare plugs .Eventually the oil will burn out and it could get back to normal...but keep the rps low. ...CONFERM that the cylinder is getting fuel at IDLE.(no fuel allows oil to foul plug.) adjust idle jet to about where it should be...(1- to 1.5 turns out from seated is a good general rule...IDLE increase?...No=turn it out somemore. IF this does not work. you may have a plugged/or clogged idle jet. (probably need carbs rebuilt.) HOWEVER you may have water in the float boal...remove carb. dump it out .check butterflys for equal operation-opening ..reinstall. try that.

Interesting. 140 is fine

Take the carb off and give it a darn good clean. (even swap them over and see if it then works on that cylinder..)

When it does fire into life it will be a bit rough and smoky That cylinder will be full of crusty oil.

Your idle jets are clogged for #1. I'd put money on it.

What kind of carbs are they? Weber IDF? Sorry if you posted that info, but I am getting dressed for work and don't have time to re-read the entire thread.

Find a good diagram for the type of carbs that you have, and blow out the #1 idle jets with compressed air after giving it a good squirt of carb cleaner. Clean the spark plug. Put everyhting back together and try it again.

If you are making 140# compression, I think you are in really good shape there. If you can borrow a leak tester, it is still a good thing to do.

I still think its easy/cheap stuff. POSITIVE WAVES!

When winter comes, consider pulling and rebuilding the carbs. If you have IDFs it will cost you about $70 (shipping included) for the kits and a few hours of your time.

Fresh rebuild is ~#150 compression. Over 130 is great compression. 130-100 is happy diving compression. 95-100 is start looking for rebuild parts compression. under 95 - pullit and start over time.

Also, you want to have compression in all 4 be ~the same.

AND, compression is just 1 part of the story. You really should do leak down too. You can have good compression, but still have crap leakdown. It sounds weird, but I had 115# compression @45% leak on my #1 cylinder. It lead to a full rebuild, as I discovered my case was collapsing at the cylinders and had to be fixed.

But, really. 140#, I think you are going to be just fine once you get fuel flowing.

Could you take and post a picture of the top end of your engine bay, so we can see your carb set up?
Zach

Thanks everyone for the help by the way.
Just studied the carbs a bit and took photos. I have two Weber 34 ICT, I believe. Looks like They have a one into two intake. The outsides of the carbs are a bit dirty, but the throat looks clean.
Isn't this set up just two single carbs? So in theory---with the shared intake, shouldn't #1 be getting fuel if #2 is getting fuel? Don't the two cylinders just share the same fuel. ?

Here are some pics of the carbs and set up.

Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment

Click to view attachment

If you are getting fuel to number 2, you will get it to number one with a single barrel carb.

Check the compression again on those two cylinders.

Rich

no spark on # 1 or no open of exhaust valve, bad, lifter, cam, rocker, or push rod. if you have 140# psi on #1 i suspect no spark, you said you fixed the wire, what how? you did not say you confirmed spark, pull the spark plug insall it back on the wire and crank the motor while watching the plug varify spark..... also just for grins varify you have the wires correct looks like 1-2 could be backwards in the photo but cant tell for sure...

I confirmed spark a few posts up somewhere in this maze. I pulled the plug out and watched it spark away. I was hoping it wouldn't, but it did. The wire just separated from the connector and I screwed it back on.

It's starting and idling way to well for the wires to be backwards I would think.

I wish cars could talk. This must be what veterinarians feel like.

I ran some spray carb cleaner down the carbs while it was running. No change in #1. 1/2 side carb increased idle when I sprayed carb cleaner in. 3/4 side bogged down when sprayed in. Does this mean anything special?

I might be crazy, but I swear for 10 to 20 seconds about a minute after I started all this cleaner spraying while it was running, It seemed that the noise went away. But it was right back and I'm not sure if I'm making it up or not.

I did have black oil spatter (like it was forced out with pressure) on the ground under the inner driver's side half of the motor. just left of center. This was odd because the oil in the motor that leaks out on the ground is pretty clean.

I don't really know where to go from here.

What's the correct type or the best kind of pressure tester to have? Mine is pretty old and just has a rubber nipple that I have to hold down in the spark plug hole. I don't even think it will reach #2 spark plug hole. Is there one that threads in like a spark plug and has some reach to it or an hose or extension? I'm ignorant in this area, or most areas I guess.

D'oh. You have exceeded my knowledge area. I heard dual carbs and assumed IDF, which was silly of me. I'm glad no one asked me to back up my bet with cash.

For shits and giggles.... Start the engine and then pull the #1 and #2 spark plug wires. See if there is any change to the engine. You want to see if it is running on just 3&4.

Go to the store and get a more modern compression tester. You want the kind that threads in. They are not expensive. And see if they will loan or rent you a leak down tester.

Do you have a carb sync? Looks like this:
or the older crappier kind looks like this: .

If so, are your carbs drawing the same at idle?

Is your linkage balanced right?

I am looking at the Weber Tech Manual (get a copy if you don't have one - you WILL use it. ) and there is still an idle jet that is worth pulling and blowing out with compressed air.

You have checked valves.
timing has to be close if it is running, but have you checked it? Do you know where your engine is timed?
you have spark
Your variables unknown are fuel and compression.

Zach

You might have a dropped valve seat. That would explain the noise at times and loss of power. The compression checks good now because the valve seat is in place, but it pops out every now and then.

Ok, here comes a lot of words. Thanks for the pics.
I've already done the pull the wire thing and I have a change when I pull #2 and no change at idle with #1. I also have a change when I pull # 3 and # 4. I did notice today, I pulled #1 wire while I revved it at about 3 grand steady and I noticed some change, so It must be firing somewhat. I think I'm on about 3 and a half power. (that doesn't make sense) I also checked the spark again and compared it to the # 2 cylinder sparking and it appears the same.

It actually runs pretty well considering and idles pretty evenly, but it has that horrible noise. I know (claim to know) it's not firing on #1 at idle, or not at it's full potential. The new plug is already black. I think there's so much oil in the combustion chamber that it can't fire properly or get a proper fuel air mixture.
There's fuel because #2 is firing well and I can look down the carb and see the fuel going in.
Maybe the left side carb is running lean? Can anyone explain why the idle on the driver's side carb increased with carb cleaner sprayed in and the passenger side carb bogged down when cleaner was sprayed? I could probably assume the carbs are not synched up properly.

One more thing---it appears this engine likes to leak a lot of oil even when parked. When I ran it today for about 3 to 5 minutes, it dropped the standard oil leaks on the ground which are pretty clean and clear.
It also dropped some black oil, almost like it was forced out of somewhere on the driver's half of the motor where there is carbon build up. Like left middle. Can oil be forced out of where the push rod tubes meet the case? Or where the heads meet the cylinders? I don't know If I'm saying what I mean. (leak pics below)
Could it be forcing the combustion chamber air out of where the head meets the cylinder? Sometimes the noise sounds like a loud slap like you can have in an exhaust leak.

Getting close to just driving the crap out of it until I reach catastrophic failure.

Anybody in or around Seattle have a cheap running motor they don't need around.
Also, What's a fair price to pay for a running stock 2.0 liter. ?



Click to view attachment

So you have spark, fuel and compression?

Please recheck compression... the bore and cylinder rings must be so choked up. It's getting very close to the stage where you're going to have to pull the head

Cars are usually easier to diagnose than animals... But not in this case I'm enjoying following along though, and have my fingers firmly crossed for you

If you are going lean on #2...

Okay, lean is bad. And can cause all sorts of problems. Your carbs need to be balanced against each other and synced properly or you are going to have continuing very hard to fix problems. I know, I just went through it.

If you are lean on 2 and not getting fuel on 1, but then 1 starts working at higher RPM, I still think your issue is in your carbs. As revs go up, you move from your idle jets to the intermediate and main jets. A blockage in idle will cease to be a problem as the carbs route the fuel through other jets.

BUT lots of driving is done on the idle jets, which would allow the plug to foul up.

You need to fix the lean issue. Get your carbs right. Get the linkage right. Look for my thread or NYChef's thread earlier this month or late last month on carb balance. Pull the idle jet out and clean it. with carb cleaner and compressed air. It is located on the outside (non-engine-facing side) of the carb, and is a brass screw just up and to the left of the pump jet. I can see it in your engine pictures (second picture from the bottom). It is NOT the one brass screw with the spring on it, the other brass flathead screw that looks slightly inset in the carb.

Reclean your spark plugs and try again.

I can't say this enough. It is critical that you get the carbs balanced with one of the tools I pictured above, and the linkage right. Your engine will never run right if your dual carbs are out of sync with each other. The good news: this is all CHEAP stuff. just take time and a Syncometer.

Zach

More likely that the driver's side carb or carb to manifold has a leak. When you squirt carb cleaner in/on the carb it temporarily seals the leak and the engine runs differently for that brief moment.

I'd get a couple of kits and rebuild the carbs before going any further. It's cheap and easy enough to do. Then I'd drive it for a while. Don't thrash it, but get it driving off the idle circuit and see if you can clear out that #1 cylinder a bit.

One more thing. the really black spots could be carb cleaner that dripped off the motor and got blown around by the fan. It will clean the grime it comes in contact with, and would probably be totally black by the time it dripped off.

It will evap faster then oil (lots faster) leaving a black stain, so thats a good indicator.

Zach

I only sprayed carb cleaner down inside the carb.

I was thinking of this too. Spray the carb cleaner on the outside of the carbs by all the gaskets: the ones from the carb to runner and from the runner to head. There should be no change in engine tune when you do this. If there is, then you have a vacuum leak and must fix it.

If one carb is feeding 2 cylinders, how can one cylinder be getting gas and the other not??? If the jets were cloged, both cylinders would not be firing.

My thought is that if 1 is getting nothing at idle, and 2 is getting little it could still be a clogged jet. Especially if #1 is sucking less air then #2. #2 might be getting just enough to fire off idle, while 3&4 are doing most if not all of the work.

Course, I could just be retarded, and totally wrong. It has been known to happen lots of times before.

*shrug*

Zach

Or as two posts above it's a manifold or gasket issue. If there is a leak here it would make a hell of a racket and the cylinder would not be getting a fresh supply..

Done the second compression test yet

Yes. I rechecked it the best I could and it #1 was still 130 to 140 ish. I have to go buy a better test gauge if I'm going to check all the cylinders. The plug was already oily black though. Not fouled up yet, just the color of the night.

Is it possible that the combustion chamber air could force out under compression where the cylinder meets the head?

Yes but it would be making a very different noise. This now has me stumped, you have compression, fuel and spark.. I have a feeling that fuel isn't getting through though..

I think it's getting enough fuel. I was just posing the question of if it might be lean because of the difference in reaction between the two carbs when I spray carb cleaner down them. Usually the normal reaction for me in the past has been they should bog down a bit with cleaner sprayed in them(I think).
Probably makes sense that there is some type of vacuum leak.

But, I think (I could be wrong) I could fix my carbs all day and I'd still have the same problem and noise. I think I will still see if the needle is needing cleaning and check if the two carbs are adjusted somewhat closely together. I believe the linkage is proper.