Heat shed, what am I missing to cool her down?, *Update - 1st Test Run after cleanup - still HOT Options

[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]

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]

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 (IMG:style_emoticons/default/lol-2.gif)

[Ansbacher]

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

Ansbacher

[nditiz1]

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]

28* at what RPM?

3500+

[JamesM]

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?

(IMG:http://www.914world.com/bbs2/uploads_offsite/live.staticflickr.com-18763-1594481587.1.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/live.staticflickr.com-18763-1594481589.2.jpg)

(IMG:http://www.914world.com/bbs2/uploads_offsite/live.staticflickr.com-18763-1594481589.3.jpg)

[douglastic]

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.

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