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Wed Jan 19, 2005 6:56 pm

Any advice would be great.

The situation:

58 bug
1776cc
stock heads
dual Dells (36mm/32 venturi's w/60 mains... the usual)
aftermarket porche fan kit from Bernie Bergman
electronic ignition (no points)

The car runs great until it starts to warm up, then I get a little bit of a power loss.
I park the car, get out, and check the temperature (with my hands) at the base of the intake manifolds... the left side is so hot I can't keep my fingers there for more than a second the right hand manifold is just warm.
I'm guessing my power loss is due to a pre-ignition condition on the left.
Okay, so I know about how cyclinder #3 over heats because of the oil cooler getting in the way but of couse, I don't have that (I have a full-flow system).

things I have tried:
1) synced my carbs with a unisync
2) adjusted the valves
3) sprayed carb cleaner on the intakes to check for leaks
4) properly timed (I don't trust the guns... I get it on the road and test)
5) checked exhaust headers... they were tight

Anything else I'm missing here?

Thanks,

-Mark

Wed Jan 19, 2005 7:01 pm

BugBear wrote: Any advice would be great.

4) properly timed (I don't trust the guns... I get it on the road and test)
,

-Mark

Mark, no offense but you need to use a timing light...i used to time by ear and "testdrive" years ago...i had one particular engine i built that ran HOT...real hot.....turned out, even though it *seemed* to run great, that at full advance i was getting close to 50degrees advance...not good...car ran great, and i never heard detonation(most of the time you don't), but it was way over advanced and that cause it to run hot and lose a bit of power...

Wed Jan 19, 2005 7:17 pm

bugninva wrote: BugBear wrote: Any advice would be great.

4) properly timed (I don't trust the guns... I get it on the road and test)
,

-Mark

Mark, no offense but you need to use a timing light...i used to time by ear and "testdrive" years ago...i had one particular engine i built that ran HOT...real hot.....turned out, even though it *seemed* to run great, that at full advance i was getting close to 50degrees advance...not good...car ran great, and i never heard detonation(most of the time you don't), but it was way over advanced and that cause it to run hot and lose a bit of power...

No offense taken!
Thanks for the reply.
I will try your advice and post the results.

Thanks,
Mark

Wed Jan 19, 2005 10:58 pm

If the timing thing does not solve your overheating problem try this next step.

Do you have ALL of your sheet metal in place?

There is a small piece of sheet matal that goes under the cylinders to keep the air moving around the cylinders.

3 and 4 are always hotter than 1 and 2. Just the way it is.

If you had an oil leak from the oil cooler it will collect on cylinder 3 and 4 and dust/dirt will collect onto the oil and will not allow the air to flow freely around the cylinder fins causing them to get real 'HOT'. If thats is the case, pull the motor and remove all the tin. De gunk the fins, you might need a pressure washer and hack saw blade, dry out and reinstall tin and motor.

Happy driving.

Roger

Wed Jan 19, 2005 11:38 pm

Although a rare occurance, mislabeled jets do happen. You should pull out your idle jets and check their size. If you can't do that, try swapping them from the left to the right.
Its not very likely to be your problem, but doing this check will cost you nothing.

Wed Jan 19, 2005 11:43 pm

Good point Bruce I didn't catch the dual carbs.

The left side could be runnung real lean causing that side to get hotter than normal.

Roger

Thu Jan 20, 2005 11:46 am

Yeah, I hooked up the gun last night and guess what?
It was dead on. :wink: (7 degrees advance at idle)

I'll dig into it more on the weekend.
That's a good point about the jets.
My bro rebuilt the carbs (and you know you can't always trust the bro)
I have blown out all the jets and cleaned them up.
I have a bigger set of jets I may throw in there just to test.
I'm running the 32mm venturi's which are small and so 60 main jets should be fine.
I'm going to disassemble the linkage and re-tighten the intake manifold for good measure.

Thanks for the posts... TheSamba is great.

-Mark

Thu Jan 20, 2005 12:08 pm

It's fairly important that the distributor and its' drive gear be installed properly. When the rotor is aligned with the notch, it should be on TDC at number one. The lobe on the distributor cam is retarded by a few degrees for number three, so if it's not correctly installed, you have the retarded spark at the wrong cylinder. It was done to help to cool number three.
Every little bit helps...

Thu Jan 20, 2005 2:00 pm

Interesting, joemac, was this retarded #3 lobe done on all stock distributors even after the oil cooler was moved?

Fri Jan 21, 2005 5:01 am

BugBear wrote: Yeah, I hooked up the gun last night and guess what?
It was dead on. :wink: (7 degrees advance at idle)

If you have a 009 dist, there's your problem. Your timing is too retarded. 7º at idle will give you 27º total. Give it 5º more.

Mon Jan 24, 2005 11:54 am

Before you get too into this, playing with carb jets and the like, check your spark plug wires.

A bad or shorted wire will cause this problem, I know because I did all the things that are being suggested to you once, and it was one bad wire.

Good Luck

Mon Jan 24, 2005 4:05 pm

Bruce wrote: BugBear wrote: Yeah, I hooked up the gun last night and guess what?
It was dead on. :wink: (7 degrees advance at idle)

If you have a 009 dist, there's your problem. Your timing is too retarded. 7º at idle will give you 27º total. Give it 5º more.

Yeah Bruce, I'll give it a try.
But if it's too retarded why would it heat up just one side?

Mon Jan 24, 2005 4:07 pm

VWDad wrote: Before you get too into this, playing with carb jets and the like, check your spark plug wires.

A bad or shorted wire will cause this problem, I know because I did all the things that are being suggested to you once, and it was one bad wire.

Good Luck

Thanks for chiming in VWDad.
The wires are brand new (and clean).
That does remind me that I should pull the plugs to see what they look like.

Sat May 16, 2015 1:52 pm

I JUST BUILT MY 1915 WITH DUAL WEBERS AND I KEPT HAVING THE LEFT SIDE HEAD RUNNING HOT ABOUT 200 DEGREES HOTTER THAN THE RIGHT SIDE,I TO THOUGHT IT WAS JETTING OR TIMING ETC AFTER ABOUT 3 WEEKS OF TRIAL AND ERROR I REALIZED THAT THE PROBLOM WAS MY NEW SCAT SHROUD WITH HEATER DUCTS.APPERENTLY THE DUCTS ARE SO LONG THAT THEY WERE BLOKING THE AIRFLOW TO 3AND 4 CYLINDERS AND THE ONE ON THE RIGHT SIDE WAS INSTALLED UPSIDE DOWN AND WAS COMPLETLY BYPASSING THE DUCT AND WAS OVER COOLING THE RIGHT SIDE.SO LOOK INSUDE AND THE HEATER DUCTS SHOULDNT BE STICKING MORE THAN HALF AN INCH AND EVEN THAT IS ALOT. I SPOKE TO SCAT AND THERE STANCE WAS OH WELL NO COMMENT.SO I LEARENED 2 LESSONS,1 ALWAYS CHECK THE HEATER DUCTS AND 2 NEVER BUY SCAT PRODUCTS SINCE THEY DONT CARE ABOUT QUALITY OR CUSTOMERS.

Sat May 16, 2015 6:17 pm

boy this sounds familiar. I have a 1776 except with the Kadron system and mine is doing the same thing. I wish I had an answer, but have you checked for a vacuum leak? spray some carb cleaner around the intake where it bolts on to the head and see if your engine speeds up. If it does, you might wanna replace your gaskets.