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nditiz1
Update - pass side tin removed. Signs of leakage.

*Update* - Webers were successful in scooting the teener down the road, but head temps still reached 400, engine drop to follow shortly.

Stock 2.0 Engine
Converted to carbs - (Dual 40 Dells - 60 Idle jet)
Engine tin in place - needs seal on the passenger side
Thermostat - dead/expanded - flaps auto spring to full open
Valves set .006/.008
Timing 28 - New Pertronix SVDA - vac plugged when timed to 28
No AFR setup - want to say rich not lean
New plugs NGK B6ES gapped to .028
*Updated info based on comments*
Oil pressure when hot 40 PSI at 4k - so looks ok
Oil currently in the block unknown - dark lol, but within the min and max marks
Targa was on during test run
Deflection flaps present
Cooling fan has 1 broken fin
CHT gauge is Dakota Digital under cyl#3 spark plug
Engine lid is currently off - is this a major cause for the issues? - found the posts where this is not an issue
Dealer installed AC - Box and grate still in place - is this robbing the cool air from under the car at speed?


Running oil temp 240/250F 85F ambient temp
Head temps in 4th on flat cruising at 65 mph at 4k RPM - *400 and climbing if going up a hill
Head temps in 3rd up and down hills *395, but can hit 400 if I get on it just a little

Compression test was

Cyl #1 - 135
Cyl #2 - 135
Cyl #3 - 130 - CHT temp sensor
Cyl #4 - 135

Assuming the carbs are not lean (went 3 turns out, and now went to 4) what should I check next? I thought maybe I needed a rebuild since the compression numbers cold were around 125 with with a 12 psi gap between 2 of the cylinders, but this warm compression check looks healthy.

The plugs do look a little white, but the last run I did was in the garage with it running at idle and some briefs to 3500 RPM to ensure the timing was correct. I know this is not to preferred method to check plugs as they should be done driving regularly and then shut off the engine and not let it idle to get a true reading. I have a gas tester I can maybe hook up to check the CO2 at the tail pipe (yes, I should have an AFR to get better readings)

In the garage I was running at 350 head temp just at idle ambient temps 82. I know sitting has no air flow. I feel like when I rebuilt my last 2056, I could idle in the garage all day long at 300 or under.

Let's assume the carbs are rich enough in the mixture so as to not be lean, will the engine seals being tattered and 1 missing (most crucial side dry.gif ) be enough to make even back road driving push cyl 3 head temps to 400 and above?

Plugs - less than 50 miles - maybe not enough time
Cyl 1 and 2
IPB Image

Cyl 3 and 4
IPB Image
infraredcalvin
Eliminate simple variables:
Fix thermostat and get flaps in working order - make sure these are not operating backwards.
Fix any missing seals
All fins in tact on your fan?
Deflection flaps underneath body installed?

Don’t assume you’re not running lean, plugs are telling you otherwise if there looking a bit white, what does your tailpipe look like, white or black?

Back off the timing a bit - different engines need to be set individually to where they want to run best

Check your oil, proper weight range for your region? Run 1/2 qt over full.

Why are you cruising at 4K in 4th gear, do you not have a 5th? 4K seems a little high for cruising.

Lastly, an afr setup will eliminate the rich/lean assumptions.

Bleyseng
What oil are you running? What oil pressure do you have hot?
nditiz1
Oil pressure hot looks good. I was at 40 PSI running in 4th @4k

Deflection flaps on the bottom are in place
The fan has one broken fin
Tail pipe looks black, smells rich, but not a good determination of correct mixture

Oil is in between marks, I am going to be changing to 20W-50 VR1 so I know what it is running, this is a good spec for Maryland climates

I was cruising in 4th because I knew 5th, even on flat ground was going to net 425*+

I had tested once, before running through these checks/tweaks, and it was headed there if I didn't gear down and ease up on the highway. The short sprint I did just yesterday in 4th was only about 2 miles, some hills, but nothing to extreme. It also doesn't change the fact that I could easily hit 400 on the slower roads 50 mph while running in 4th.
Ansbacher
Even though you are reporting 28 degrees, it sure sounds like a timing issue, especially when you say it is doing 4,000 RPM in 4th. Do you have a spare (non-vac type) distributor to substitute? If so, install it, set timing, and see what temps and RPMs do. I have a 2.0 with dual-dells and I went through this same thing when I tried a vacuum dizzy. Went back to my 009 and all is well.

Ansbacher
nditiz1
QUOTE(Ansbacher @ Jul 5 2020, 10:06 AM) *

Even though you are reporting 28 degrees, it sure sounds like a timing issue, especially when you say it is doing 4,000 RPM in 4th. Do you have a spare (non-vac type) distributor to substitute? If so, install it, set timing, and see what temps and RPMs do. I have a 2.0 with dual-dells and I went through this same thing when I tried a vacuum dizzy. Went back to my 009 and all is well.

Ansbacher


@Ansbacher - were you running a pertronix in your 009 or points? I had a 009 with pertronix in the car and just swapped it to SVDA pertronix to help with the 009 flat spot and carbs. The SVDA is supposed to help with the transition smoothing out as it advances the timing with light throttle due to the highest vac pull. I could plug the pod and it should act the same as the 009 with a pertronix in it. I also have another 009 with points I could try.
Ansbacher
Nditiz1: Yes I am running a Pertronix in my 009.

Ansbacher
ndfrigi
Hello,

In addition to above suggestions/comments:
1. Try to install the passenger side seal missing you mentioned. My experienced before with missing seal or small engine tin piece on passenger made my engine hot around 240F and even to 250F on mountain drive. After installing the missing engine tin piece, temp improved.

2. Missing blade with your fan may cause lesser air flow.

3. I believed the fuel mixer adjustment of 3 or 4 full turns is too
much. check below suggested tuning on carbs. Hope this is same tuning you need for your carb.

https://www.carburetion.com/weber/adjust.htm

nditiz1
QUOTE(ndfrigi @ Jul 5 2020, 12:32 PM) *

Hello,

In addition to above suggestions/comments:
1. Try to install the passenger side seal missing you mentioned. My experienced before with missing seal or small engine tin piece on passenger made my engine hot around 240F and even to 250F on mountain drive. After installing the missing engine tin piece, temp improved.

2. Missing blade with your fan may cause lesser air flow.

3. I believed the fuel mixer adjustment of 3 or 4 full turns is too
much. check below suggested tuning on carbs. Hope this is same tuning you need for your carb.

https://www.carburetion.com/weber/adjust.htm


I will definitely try to squeeze it in, as well as try to tape up the remaining ones. Just trying to see if the engine temps can be managed or the engine needs to be dropped (looking like it will need to to at least replace the fan)
* This leads back to the main question * Do the rubber seals make then engine run that much cooler? I'd understand if I was running at 380 - 400 while pushing up a hill, but I'm hitting above 400 on a flat.

I'm sure 3 or 4 is a little much, but not overly much. I wanted to go on the rich side as a test to bring the temps down. I did have them set to the best lean approach, but came up with these high temps.

One thing to note is I'm currently running the engine lid off - is that throwing my numbers high? Debunked
JamesM
Pretty much everything you mentioned is most likely contributing. I would start with getting a non-broken cooling fan as that is an obvious one but after that (what what i suspect is the primary issue) I would look at the tuning (error on the rich side). Also, im curious with carbs where are you pulling the vacuum for your vac advance and/or retard?

Also one thing you didnt mention, how clean are the heads/cylinders under the tin? You mentioned you didnt know the state of the oil which makes me think there may be other unknowns as well (like the heads possibly clogged up with debris, grease, oil etc)



nditiz1
QUOTE(JamesM @ Jul 5 2020, 01:36 PM) *

Pretty much everything you mentioned is most likely contributing. I would start with getting a non-broken cooling fan as that is an obvious one but after that (what what i suspect is the primary issue) I would look at the tuning (error on the rich side). Also, im curious with carbs where are you pulling the vacuum for your vac advance and/or retard?

Also one thing you didnt mention, how clean are the heads/cylinders under the tin? You mentioned you didnt know the state of the oil which makes me think there may be other unknowns as well (like the heads possibly clogged up with debris, grease, oil etc)


James,

I am pulling vac adv from cyl #4. I set the carbs to being rich as I was first told that timing and carbs being lean were resulting in my overly hot temps.

The bottom of the engine is an oily filthy mess. Pushrod tubes leaking (already ordered new tubes and seals). I'll reset the carbs and try to clean up the cooling fins before the next test hit late tonight.
barefoot
I'd try to check if your cylinder head temp gauge is reading properly. i tested mine with censor immersed in boiling water to verify calibration.
BTW my similar setup runs MUCH cooler.

barefoot
Superhawk996
I'm going to stir the pot a little here. stirthepot.gif 240F to 250F is not too hot for oil. I know there is this mythology that 180F is the sweet spot for oil. Not so. 240F oil is OK but it should just be changed every 3000 miles or so.

Your head temps are hot (assuming gauge is correct). Check calibration as suggested by Barefoot.

Your head temps are hot because you're missing an engine seal. These engine seals are not optional.

Without that seal you're pulling hot air from under the engine right back up into the fan and recirculating that already heated air across the engine and heads. Recall that VW sealed the front fan tin between the two pieces of tin with caulk. This sealing of the tin was done to prevent that crack/gap between the tin from sucking in hot air under the engine. You're missing way more sealing that that! You mention that you may have other "tattered" seals. Fix those too.

The other items mentioned (timing, carb tuning, etc.) are all fine but you've got to replace that seal before you make any further conclusions about your temps.

The other issue you'll have is the A/C. I have yet to see an A/C install that doesn't completely butcher the passenger side engine tin and the associated sealing. It sort of "works" assuming the A/C compressor is there and largely filling the hole opened up by the butchery but even at it's best, the A/C conversion creates a lack of CRITICAL sealing between the bottom of the engine (where the hot air is) and the top side where the cooling fan is supposed to be bringing in COOL air.

FYI - don't sweat the loss of one blade from a cooling fan. It isn't going to affect your temperature in any meaninful way.

To address your quote "In the garage I was running at 350 head temp just at idle ambient temps 82. I know sitting has no air flow. I feel like when I rebuilt my last 2056, I could idle in the garage all day long at 300 or under."

You are right -- 350 is too hot for just idling.

You are incorrect in stating that there is no air flow. There is plenty of airflow coming from the cooling fan at idle to keep the engine cool at idle but again that assumes a proper state of tune and most importantly that the engine seals are in place and that the hot air under the engine isn't able to rise up from convection and re-enter the engine compartment.

With respect to cylinder 3&4 those plugs look too lean. That surely isn't helping. Make sure that you don't have air leaks. Sometimes you need to double up on gaskets between the cylinder head and the carb manifolds to get a good seal.

Did you use head gaskets with the rebuild? Hopefully no. Even if you didn't use gaskets - are you sure your heads are seated properly and not leaking? A leak at the head can cause a lean condition.

Make sure the carb jets are clean on cylinder 3&4 side. Measure the idle jets with a wire size #drill bit if necessary to ensure size is the same on 1/2 side and 3/4 side. Both Dell's and Webers run on the idle jet and progression circuit way more than you might think they do before tranistioning to the main jet circuit.
nditiz1
Thanks barefoot. I will test it. Are you also running a stock 2.0? I do have an additional Dakota Digital CHT gauge and sensor.

I did another test run last night.
Numbers were better, but ambient temps were 75 so 15 degrees less. There was still an issue running on flat ground in 5th. If I was on a slight downward slope I could feather in 5th to keep it around 398. My speed would also go down since I could definitely not maintain 70 mph in 5th and keep the heads cool. I temporarily used some duct tape to close up any gaps just as a test run. Not sure it helped much. I also reset the mixture screws to 1/2 to 3/4 turns out from just dropping idle RPM. Dellorto book specifies 1/2 turn. I could try to time it down 1 degree to 27 from 28. Oil pressure at 2700 RPM was right around 30psi. At Idle when fully warmed 1k RPM - 10PSI. Even when head temps were hitting the 400 - 410 the pressure stayed good.

Looking more like I need to drop the engine to completely seal up and replace the fan. I might do the pushrod tubes and seals since I'll have it out.
rhodyguy
Fuel mixture adjuster. I'll presume you're referring to the IDLE AIR MIXTURE SCREWS. There is no absolute "correct setting". Initial common baseline setting for installing the carbs and adjusted accordingly later. So no '3 or 4 turns and good'. They control the a/f ratio at IDLE. You are off the idle circuitry when cruising around at 4K. So, using the IAMS expecting to control the head temps while driving is futile.

No mention of the last or ever cleaning of the oil cooler, of the exterior of the cylinders or engine in general. Fix the cooling vane thermostat. All systems should be in place and functional.
Superhawk996
If you sealed completely with duct tape and are still running hot. Drop the engine and figure out why its running hot and why Cyl 3/4 are running so lean.

As stated above, make sure oil cooler is clean and doesn't have a mouse house on it.

If you are starting with an engine of unknown origin don't assume there aren't blockages of the cooling fins or oil cooler.

Here is the oil cooler from one of my engines as I initially received it.

Click to view attachment
rhodyguy
Also, how have you set the air bypass screws?
VaccaRabite
This sounds really familiar! In fact I had almost the exact same issues while I was running carbs. Had to cruise on the highway in 4th, never touch 5th or it goes right over 400*.

Pull off the tins and make sure you don't ave mouse nests blocking your cooling vanes. You can do this with the engine in your car (BTDT) but its a pain. Since your car had carbs its pretty easy to just drop the engine.

My issue I figured out after I pulled the carbs and sold them out of frustration. The top gaskets I had bought were defective out of the box. There had been a bad manufacturing run where the top gaskets did not have holes punched for the jets and the engine was always running lean at speed no matter what jetting I put in the mains. It is probably worth rebuilding the carbs and making sure everything is up to snuff.

One more thing I will add, the "Factory" AC really ruins the pass side tins. If you have working AC, its probably worth it now that its hot and humid here in the MidA. BUT if yo don't have working AC, pull that crap out and sell it. Get a set of tins that have not been mangled and it will help considerably.

Zach
rhodyguy
And usually the huge piece removed from the pass side engine shelve to accomidate the comp.
Superhawk996
QUOTE(VaccaRabite @ Jul 6 2020, 10:09 AM) *



One more thing I will add, the "Factory" AC really ruins the pass side tins. If you have working AC, its probably worth it now that its hot and humid here in the MidA. BUT if yo don't have working AC, pull that crap out and sell it. Get a set of tins that have not been mangled and it will help considerably.

Zach


If you decide to pull the A/C and cant find 2.0L passenger side tin at a reasonable cost, I can fix your butchered existing 2.0L tin. Did this a few months back for another member.

Starting condition
Click to view attachment

Finished repair
Click to view attachment
nditiz1
Awesome info all!

Ok so I did mean idle mixture screws and you are partially correct about being off them at 4k. If the road was flat enough I could still be on light throttle. Butterfly throttle and vacuum I believe dictate which circuit you are on. I do have a set of webers I could replace these Dells with. Dells are new to me, but the whole dual carb setup is pretty similar. Let me look in the Dell book about the AIR-BYPASS. I didn't set that. I only synced the carbs with the idle adjuster and the sync gage and the idle mixtures. EDIT *air-bypass - The barrels on the carb are pretty close on each side so I don't think I need to mess with that.

@Superhawk996 - Thanks for the offer and I think I will take you up on it. I have another set of pass side tin, but I'm not sure the condition. I feel like the oil pressure switch hole might be mangled. I will pull it out of the shed to inspect. Regardless, I wouldn't mind having an additional clean set.

I will be dropping the engine. Just put in another order to 914rubber for some more engine seals. Finishing up one with AA for the other seals that 914rubber doesn't have and ordered a new clutch pkg. Oh and a fresh thermostat from Awesome Powerder Coating.

So after all of this I should have a clean looking, less oil leaking engine.

I should be able to get this squared away without a rebuild right especially with compression numbers warm at 135 and consistent across all 4?
rhodyguy
I was unsure whether you were running Dels or Webers.
VaccaRabite
I would not tear down an engine making 135PSI in all 4 unless it was knocking or giving me some other indication of very bad things to come. While 135 isn't brand fresh, its a solid number for an engine in mid life, especially with 400* head temps!

Swap the Webers on and test. Can't hurt and will give you a second baseline. but if the webers have sat for a while they may need rebuilding too. That said, if the webers are anywhere near correct I bet you see a big drop in head temps.

Zach

rhodyguy
Which flavor of Webers? 40s or 44s? Used, unknown carbs are just that. Same thing goes for a used and worn linkage.
rhodyguy
Which flavor of Webers? 40s or 44s? Used, unknown carbs are just that. Same thing goes for a used and worn linkage.
nditiz1
QUOTE(rhodyguy @ Jul 6 2020, 08:31 AM) *

Which flavor of Webers? 40s or 44s? Used, unknown carbs are just that. Same thing goes for a used and worn linkage.

Known Weber 40s I pulled off my last teener. They are known good working condition. I drained them and ran brakeclen through them before putting them away. Was going to throw them on a 1600. They were jetted for 2056, but I have plenty of Weber jets to be able to swap in if needed.

Linkage is new, just put on CSP Bellcrank.
rhodyguy
Go for it. The Tomlinson Weber manual from Cb is much better than the Del book.
nditiz1
QUOTE(rhodyguy @ Jul 6 2020, 08:46 AM) *

Go for it. The Tomlinson Weber manual from Cb is much better than the Del book.

Wait what?! I have both Tomilinson's books. I thought they were both the same with the cover changing to a picture of a Dell instead of a Weber lol-2.gif
Ansbacher
Nditz1: Did you ever try running it with the vacuum detached and plugged off, as previously discussed?

Ansbacher
nditiz1
QUOTE(Ansbacher @ Jul 6 2020, 09:12 AM) *

Nditz1: Did you ever try running it with the vacuum detached and plugged off, as previously discussed?

Ansbacher


I did in last night's test run. Didn't seem to change much. Is 28 too much timing?
rhodyguy
28* at what RPM?
nditiz1
QUOTE(rhodyguy @ Jul 6 2020, 09:39 AM) *

28* at what RPM?

3500+
JamesM
QUOTE(nditiz1 @ Jul 5 2020, 12:54 PM) *

James,

I am pulling vac adv from cyl #4. I set the carbs to being rich as I was first told that timing and carbs being lean were resulting in my overly hot temps.

The bottom of the engine is an oily filthy mess. Pushrod tubes leaking (already ordered new tubes and seals). I'll reset the carbs and try to clean up the cooling fins before the next test hit late tonight.


Pulling a vac signal from a single cab barrel is most likely causing a pulsing signal wihich could result in erratic timing. If you are getting 28 degrees full advance with just mechanical advance I would try just eliminating the vav advance. If the bottom of the engine is a mess though guessing the cooling fins are at least partially clogged up as well. Drop the engine, take care of "all the things"
nditiz1
James - I went with the preferred method of pulling vaccuum for any Distro Vac pod. That is pull from cyl #4 OR #1, but most of the time carb pairs only have one vac port unblocked and that carb usually sits on the 3/4 side. Also, I am using an anti-pulse valve so as to not get any pulsing.
nditiz1
Update*

Went out for another test run last night. Ambient temps 73 and dropped to 70. Car did a little better, but it may have been because the temps were slightly lower than the 75 my previous test run was at.

Sitting for a few years, the Webers still performed well. My putting them away dry really helped. It is good to have another data point to help throw light on this heating issue. I will start the engine drop now.

Side question for Dellorto owners - I noticed some Red RTV in the bottom of each of the barrels filling in a side pocket. Is this some Dellorto trick to help with some issue? I'm never a fan of "not well known" carb fixing methods especially if RTV is involved.
hcdmueller
If I remember correctly, certain cars factory equipped with Dells had some sort of locating lug that fit that pocket. If the pocket is unfilled you would get whistling sound.

Just found gaskets

https://vwparts.aircooled.net/Dellorto-DRLA...stle-gasket.htm
nditiz1
@hcdmueller that is probably what was done to help stop the whistle

**Update** In order to not have the car down in hopes of limping it to the East Coast meetup next Friday I removed the 3/4 side tin engine in situ. I knew if I did a complete drop that would rule me out to make it up there in the teener.

This is what I found. Nothing completely blocking the cooling. I see some smoodge build up on the cylinders. Some leaves, electrical tape, a colored pencil (Crayola magenta) resting on the cooler. Must have sucked up a colored pencil through the fan.

Would these minor items be enough to prevent well enough cooling?

IPB Image

IPB Image

IPB Image
douglastic
QUOTE(nditiz1 @ Jul 11 2020, 07:33 AM) *

Would these minor items be enough to prevent well enough cooling?


I'd say it definitely isn't helping your cooling . . .

Looks like quite a bit of blockage. Clean it out and see what happens!
rhodyguy
how junked up is the bottom side of the cooler? Why would you not clean it when your this far into the project? Hit the top of the cooler with a can of brake cleaner. Expect the cyl build up to be likewise on the driver's side.
Superhawk996
Point of note:

Look at the oily residue between the head and the cylinder. Typically, this indicates a poor seal between the head and the cylinder.

A leak at the cylinder to head interface not only leaks oil. It becomes a 4 leaks for the price of 1.

Leaks air IN on the intake stroke, leaning out the fuel charge. Don't under estimate the potential of this leak to cause a lean condition.

Leaks on the compression stroke

Leaks on the power stroke

Leaks on the exhaust stroke.

Each is a matter of degree dependent on how major or minor the leak is. By the time you can see the oily / dirt build up, the leak is larger than you might think. Usually this oily film is worse on the bottom side due to gravity.

The oil film and crud on any of the cooling fins impairs cooling. With respect to the oil cooler, you don't have a major blockage but that debris on the top will hurt cooling but probably isn't the source of your problems. When you look at any piece of screen, or an oil cooler, you would be amazed at how little "free area" there really is for the air to flow though.

I'm also very curious about why the first photo shows the flap closed over the oil cooler. Unless the engine is hot, this flap should be raised when the engine is cool. In the 2nd photo it looks to me like you're having to use your finger to raise and hold the flap open to see the cooler. When the engine is cold the flap is raised (blocking flow to the cooler) for quick warm up. When the engine is hot, the flap closes across the top of the oil cooler and directs air flow though the cooler.

Are your flaps hooked up correctly? If that engine is cold, it appears that they are operating backwards unless you have the thermostat disconnected and are in the fail-safe hot position all the time.

http://www.914world.com/bbs2/index.php?

http://www.914world.com/bbs2/index.php?sho...112369&st=0[/url]
nditiz1
@Superhawk996 - Excellent points. To address the flaps, the thermostat is expanded and dead. The wire is no longer connected. I have a new one ordered, just waiting for delivery.

I will clean up the oil residue best I can. My fear is one of your other points - LEAKS - While I did do a compression and they seemed good the leak down was not so favorable even warm and worse when cool (20 - 30%) The leaks between the block and the jugs and the jugs and the heads are probably all attributing to the lean cyl 3.

Maybe I will rebuild this into a 2056.

I will clean everything up and add seals where missing and button it back up. Hopefully temps stay down and I can drive a long distance to make the east coast meetup. Otherwise engine rebuild is in order.
Superhawk996
QUOTE(nditiz1 @ Jul 11 2020, 04:23 PM) *

@Superhawk996 - Excellent points. To address the flaps, the thermostat is expanded and dead. The wire is no longer connected. I have a new one ordered, just waiting for delivery.

I will clean up the oil residue best I can. My fear is one of your other points - LEAKS - While I did do a compression and they seemed good the leak down was not so favorable even warm and worse when cool (20 - 30%) The leaks between the block and the jugs and the jugs and the heads are probably all attributing to the lean cyl 3.

Maybe I will rebuild this into a 2056.

I will clean everything up and add seals where missing and button it back up. Hopefully temps stay down and I can drive a long distance to make the east coast meetup. Otherwise engine rebuild is in order.


30% leakdown is quite a lot. For relative comparison my Miata engine at 220K miles had a leakdown rate of 15%.

While you have the tin off you may want to take the opportunity to retorque the cylinder head bolts while you have access to the upper fasteners. That might help seal up cylinder 3/4 leaks a little bit.

If you're going to do attempt that - soak with penetrating oil for a day or two. Then loosen them 1st and then retorque up to spec. Obviously there is some risk to trying this - stud may loosen in case 1st or you could break a stud.

barefoot
One thing I noticed when I was first cleaning up the 2L heads I'd acquired with a complete 2L motor is that there was a LOT of casting flash mostly blocking cooling fin passages near where the exhaust ports pass by. With accumulated junk, these passages were completely blocked. So after cleaning I had to go into these passages with drills to clean out the aluminum flash.

Click to view attachment
type2man
Buy some 62 idles, and then get all your gauges, throw them in the trash and just drive it.
VaccaRabite
What were your head temps with the Webers bolted on?

Pulling the tin was smart, you have a lot of crap built up in there.

Superhawk is right about the leaks. Before you pull it apart, just check the torque on your head bolts. And maybe put a tad more torque on the bolts that are on the leaking jug and check leak again.

Its very possible that you have slightly warped heads, and its very possible that you have collapsed registers on the case (which was the problem with my engine ages ago when I had good pressure but bad leak down numbers).

Zach
nditiz1
Zach the head temps were about the same with the Webers.

Just got done cleaning a bunch of the muck out. I'll try to bolt it back together in the next day or so and retest. This is make or break for the east coast meetup on Friday.

I think this fall an engine top-end rebuild is in order. The new garage will be built so it will be plenty of clean space to get it done.
nditiz1
*Will need a drop and rebuild

Not sure what else I can do.
-I have cleaned out most if not all the gunk on the 3/4 side
-sealed up every hole and crack
-jetted the idles up to 55 from 50 on a set of webers
-set timing to 27 degrees

Tonight I performed another test run and things seemed like they were doing better than last time. Ambient temps 70. Engine temps stayed under 400 in 5th on the highway. After a 20 minute drive I got on it a little from rest back onto the highway. Temps started creeping up as they did on the way to the city. I could no longer keep the temps under 400 while going up a long slow incline. Dropped it to 4th helped a little, but never brought them back under 400 until I was at the crest of the hill. Mashing the pedal in 4th and winding it out for a few seconds actually helped in bringing the temp down. I can only assume this was due to the large burst of air and the accelerator pump on the carb dropping some much needed fuel into a leaning out cylinder. I'm already running 135 mains. I feel like this engine should be running 120 mains with 50 idles, but i was trying to throw more fuel just to see if that would keep the temps under control (I have several jets for tuning so it wasn't any additional cost to test) At one point when I was really stressing the engine 415 degrees or so the oil pressure light kicked on. I let off the gas and it went out after a few seconds. I checked the oil pressure gauge and it still looked good around 30psi so I'm not sure what that was about.

So I feel like only an engine tear down can tell me where I am failing to keep the cylinder rich.
Superhawk996
Arghh . . . .

Only last suggestion - sorry if I've missed it earlier in thread. Did you check temp sensor calibration against boiling water or maybe IR temp gauge just to be sure the error isn't in the gauge?

Given that the oil light flashed on when hot I'm concerned for you. Definately don't want to drop a valve if it really is running that hot.

Out of curiosity . . . not meant to imply anything . . . are you sure you're not lugging it? Especially on grades. No harm at all running 3000-4000 rpms even if that means 4th gear. scratch that. see you were running 4K rpm in OP.

Sorry about this situation. It really does suck. Going to have to figure out why 3/4 is running lean.
nditiz1
I did not check the accuracy of the CHT. I can do that today.

No lugging was happening. On the highway in 5th I was at or a little above 3000 RPM. When I saw the oil light flick on briefly I was in 4th I think at 4000 RPM.

I think its like you said the leaking of the cylinders is too great and leaning out the cylinder. I think this shows why compression tests do not always mean a healthy engine. The leakdown from the start was suspect.
Superhawk996
QUOTE(nditiz1 @ Jul 15 2020, 07:47 AM) *

I did not check the accuracy of the CHT. I can do that today.

No lugging was happening. On the highway in 5th I was at or a little above 3000 RPM. When I saw the oil light flick on briefly I was in 4th I think at 4000 RPM.

I think its like you said the leaking of the cylinders is too great and leaning out the cylinder. I think this shows why compression tests do not always mean a healthy engine. The leakdown from the start was suspect.


Out of curiosity . . . were you able to retorque the cylinder heads a bit? And, after all these test runs are the plugs on 3/4 still that white?
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