Engine troubles

geauxtigers · Post by **geauxtigers** » Fri Jan 13, 2006 3:43 pm

Hello all! I have been having trouble with my 318. WHen it's cold it runs fine, however, when its hot, the engine runs rough until i get the engine speed up over 1000 rpm. Someone before mentioned a vaccuum leak, but i checked all of my connections and manifold bolts and they are fine. Is there something i'm missing?

Thanks in advance,
-Josh

Shaun · Post by **Shaun** » Fri Jan 13, 2006 7:23 pm

Does it ping also? If so,it sounds like your timing is retarded just a little.
Do any of your fuel lines run near the headers(could they be getting too much heat)? Your fuel may be boiling.
How hot? Ideally,your engine will run best between 150 and 180* of water temp. Have you tried putting in a cooler thermostat?
It is possible that you have a burnt exhaust valve.Put a piece of paper over your exhaust pipe while it's running and if it tries to suck it in-you have one,or more burnt valves.
It may be a vacuum leak-but if it is idling fine,I wouldn't think so. The best way to check that is to take off your air cleaner and put a shop rag(clean one) over the carb while it's running. If the rpm's increase-you have one. Find it by spraying WD-40,or better yet a solvent-tranny fluid mix,around the carb,manifold(all areas)until you pinpoint it.
Hope that helps some.

Post by **cowboy** » Fri Jan 13, 2006 9:06 pm

josh

back , have you double checked your choke to make sure it's opening up all the way after your truck warm's up , it just might be sticking a little

Post by **oneowner71** » Fri Jan 13, 2006 10:50 pm

just spitballing here... exhaust heat riser stuck?? Just a random thought...

geauxtigers · Post by **geauxtigers** » Sat Jan 14, 2006 12:50 am

Hey cowboy, yeah, it's been too long and too busy with college and all...but its good to be back in the saddle...Shaun, i will have to try some of your suggestions tomorrow...i have a manual choke (edelbrock 600cfm with ld4b intake) so i dont think its the choke...and i've recently done the valve reseat and rering on the engine so i dont THINK it is a bad valve...i wonder about the overheating thing though, that's a possibility...but what gets me though is it runs fine after i speed the engine up. i would think (there i go thinking again

) that something like a vaccuum leak or burnt valve or somesuch would affect the engine throughout the rpm range...

Thanks everybody
-Josh

Shaun · Post by **Shaun** » Sat Jan 14, 2006 1:04 am

A vacuum leak and bad exhaust valve will show up at certain rpms's-the vacuum though usually will be real noticeable at idle.
It may be that your problem is in your carburetor. What make is it and what model? I know I've had troubles with Holleys sometimes getting a little piece of something in the idle circuit and doing about the same thing-and sometimes if you get a little water in the carb it'll do just that.
Shaun

geauxtigers · Post by **geauxtigers** » Sat Jan 14, 2006 9:21 am

Hmmm...well the problems i have seem to be at idle, suggesting a vaccuum leak then...its a new edelbrock 1405 carb, i gave it the once over, so i don't think the carb itself is faulty. I'm about to go out and check the paper thing or the bad exh valve...

Thanks
-Josh

scoutski · Post by **scoutski** » Mon Jan 16, 2006 7:24 am

Josh Hi, I have 2 trucks with the Edelbrock carbs on them. It sounds like the transient control system is not functioning properly in the carburetor. What leads me to believe this is the fact that when it is cold you most likley have the choke closed a little. One of the ways to alleviate this is to change links position on the pump plunger. There should be 3 holes in the link attachment you can move this to increase the stroke of the pump plunger.
You can find the entire tuning and calibration procedures at, http://edelbrock.com/automotive/eps_sect2.html
Bill

geauxtigers · Post by **geauxtigers** » Mon Jan 16, 2006 3:29 pm

Thanks for the tips Bill! I'll have to check those out. It's been running a little better now that i've checked for vacuum leaks and just run it a little. It's still idling rough, so i'll take a shot at that pump plunger.

Thanks,
-Josh

mudbug · Post by **mudbug** » Mon Jan 16, 2006 7:49 pm

i had the same thing on mine, and after it driveing me up a wall for a month it was the carb.to manifold gasket. the s.o.b. will work just fine untill it warms up then it turns to s@@t.
tightening it wont do a thing for it, replace it and you will be running like a big dawg again.
good luck, john.

geauxtigers · Post by **geauxtigers** » Thu Jan 19, 2006 3:57 pm

mudbug wrote:i had the same thing on mine, and after it driveing me up a wall for a month it was the carb.to manifold gasket. the s.o.b. will work just fine untill it warms up then it turns to s@@t.
tightening it wont do a thing for it, replace it and you will be running like a big dawg again.
good luck, john.

Carb to manifold gasket? That's interesting...what kind was the bad one? More importantly what kind is the good one? (generic/felpro type?)... Thanks for the info mudbug...

As an update/follow-up: I recently changed my alt/voltage regulator, and although i have an average 14+ volts charging, the needles on both my amp and volt gauge are really really erratic, have i fried another regulator or ?????

Thanks for all of your help,
-Josh

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