1978 Firebird Idle Issues

FirebirdLogan

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ANY ADVICE APPRECIATED

Hello my name is Logan and I am new to the forum.

I recently bought a 1978 Pontiac Firebird, smokey and the bandit.

www.facebook.com/photo.php?fbid=102...681696575509.125212.1667916492&type=1&theater

This is my first restore, i plan on finishing it within 6 months when i turn 21.
So the head gaskets blew shortly after i purchased it and i foolhardedly decided to try and change it myself, while painting the engine while i was at it.

The paint job turned out great and the car started again after i was done, but she does NOT idle right and the exhaust smells like gas. If i were to explain how it runs i would say it sounds like its running on 4 or 5 cylinders, the link here is my car and after i let off the gas is goes chuga chuga chuga chuga and it shakes like hell. Sorry you have to copy the link, i couldnt make it clickable

https://www.youtube.com/watch?v=Yc7LGmFfpeg&feature=youtu.be[/URL]

I have some leads on the issue...

1.)When i painted the harmonic balencer it made it very hard to see where absolute 0 is for getting it to TDC. there are 2 small triangles on the left and 2 big triangles on the right, only about an inch wide if ANYONE know what the triangles mean, timing wise.

2.)VIN: 2T87L8LI56740
ENGINE MODEL NUMBER: VO317CHI/28LI56740

3.) I tried to put the distributor in correctly, here is how i did it...
After going to TDC, I used a long screwdriver to turn the little knob in the engine pointing towards the 1st cylinder and then slipped the distributor in so that it pointed towards the 1st also, which also lined up perfectly with the 1st spark plug like it should.

4.)I was a moron and didnt pay attention or take pictures of my vacuum lines and such and i have a few open right now and access to all the tubing i could need.

5.)The carburator may have been played with especially when i was cleaning it with the bottled cleaner and i had it off for about 2 week while i was playing with it, I do not know how to adjust the screws but ive heard its easy after some getting used to.

6.)Is it a myth that Firebird pushrods are different lengths with different cylinders? Like for example the number 8 cylinder needs a Minuscule amount longer rod? Because i did take care of them and oil them, and i did pay attention to where each lifter was, but i didnt keep track of which pushrod went to which..


I know thats a lot of mess-ups, i have only done straight 4's and Geo Metros before so i was in over my head a little and way to excited about this V8.
 
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Based on the serial number you have a Firebird Esprit model with a 350 engine that appears to be a Chevrolet engine from the picture.
The harmonic balancer should have a groove in it that you can paint white.
Doesnt the timing cover have a timing tab with numbers on it?
Read this on how to install the distributor http://www.nastyz28.com/~ericf/tech/distinstall.pdf
If you have any vacuum leaks because of disconnected hoses you have to close them to get the engine to run
To adjust the carburetor with the engine off turn both mixture screws clockwise and gently seat them. The turn both screws counter clockwise about 4 turns. Start the engine and slowly turn in one screw at a time a 1/4 turn watching either a tachometer or a vacuum gauge till you get the highest idle speed or vacuum reading. If the vehicle has an automatic it has to be done in gear, parking brake on and wheels chocked.
Pushrods on a stock engine are all the same length. How did you adjust the valves when you reassembled the engine?
 
First off thank you so much for your reply! Today i am working on it and trying to figure this out.

When i was putting the engine back together i was tightening the lock nut on the lifter while i was twisting the pushrods, once the pushrods started to have a little resistance to the twisting i tightened them a full half turn(while turning the engine to get the other valves you cant get on regular TDC)
Later in the week i heard that quarter turns are better so i took off the valve covers and let off a quarter turn on all of them.

My problem with the little tab on the timing cover, is i painted it and cant see the numbers, it is very clear where the numbers should indicate on the harmonic balancer.

If i put the distributor in wrong would the car even run at all?

Thanks again for replying.
 
you tigthened #1 cylinder TDC on the compression stroke originally 1/2 turn, next cylinder would be #8 and you would have had to turn the engine 90 degrees, is that what you did and continued 90 degrees through the firing order, 1,8,4,3,6,5,7,2 ?
clean the paint off the tab
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what i did was set the valve lash like i explained with the twisting and tightening on...
exhaust valves 1, 3, 4, 8 &
Intake Valves 1, 2, 5, 7

then turned it over to "Bottom dead center" read about, and tuned

Exhaust valves 2, 5, 6 ,7 &
Intake valves 3, 4, 6, 8
~~~~~~~~~~~~~~~
But when i loosened all of them a quarter turn i DID NOT do any cranking of the crankshaft.

Today i found out it has no "Dwell" because of a module sensor in the distributor, my distributor and rotor where put in Correctly, and my spark plugs are put in correctly also so that's not the timing issue.
All of the spark plugs are foiled up and the exhaust is very rich smelling so im thinking i either have an air problem, or more likely a fuel problem.

I want to rebuild my carb but the cheapest i can find in town is like 150+ the kit. I feel like i might as well buy a new one.
 
REVELATION!!!


Someone from craigslist came over today and as i was showing him the car i opened up the front 2 small barels of the carburater and it slowly stared running smoother and smoother until it sounded as if it was TOO ADVANCED...

So im thinking im gonna sink $150ish into restoring my carb and see where that takes me.

Honestly i havent heard my baby run that good since i took her apart...
Today was exciting.
 
When you say you turned it to bottom dead center, you mean you turned it 360 degrees which would bring it to TDC compression stroke #6? Do have an HEI distirbutor, because the concept of dwell deals with points type distributors. A carb rebuild wont hurt but you may just have dirt on the needle and seat. Glad to hear it's running now.
 
My boss finally caved and we rolled my car into the shop and his carb/engine guy is gonna work on it tomorrow. I'm sure she will run just fine afterwords..
But it's blowing quite a bit of white smoke. Especially when I touch on the gas, although it smells like gas to me.
When I say quite a bit it's kinda like running seafoam but only only a slightly dirty engine. I had to replace a freeze plug because it was left for years with water in the cooling system.
When I flushed it I thought it would
Never stop pushing out orange rusty water. I'm thinking its possibly the head is cracked or rusted out internally.
I did not have the cash for a head check and resurfacing.. Definentally a noob mistake.

Anyways I took the engine apart cause it started blowing some white smoke like a week after I bought it so I changed out the head gaskets. Now it's blowing more than before it seems. Then again it's not even running right so be ready for an update by Thursday.
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And yes I did mean the TDC for #6.
When I get it running better I am going to buy a pair of valve covers, cut some holes and tune the valve lash the good old fashion Chevy way.
 
It sounds like you still have a head related problem, you should have had the heads checked at a machine shop.
 
So the mechanic who was gonna check out my car popped a blood vessel in his eye last Saturday, but hes finally coming out tomorrow to check her out, so i will FINALLY have a real professional diagnosis of what the hell is going on.

I think you are right Mel, my boss says that i probably never even had a head gasket problem and the guy who sold me the car probably knew the engine was cracked or rusted out and used a quick fix. Hes been restoring muscle cars for 30 years and he told me BUY A NEW ENGINE END OF STORY. I guess that's my plan... I personally just wanna buy new heads, but he says i will throw money at the engine till the cows come home and it still might not work.

(BTW my boss is Mark Young in Portland hes know all around if you possibly have heard of him)

So I am looking for an old but running Chevy 350 on craigslist.
 
I am looking for a whole new engine because my boss insisted i do so.

He has been restoring Pony cars for 30 years so i figure its safe to just take his advice.

http://portland.craigslist.org/wsc/pts/4863542066.html

Thats the engine i plan on buying, the mechanic who was supposed to work on my car popped a blood vessel in his eye so today is the soonest he could come check it out, he will diagnose it and then i will know whether or not im picking up the engine or not.
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Check the numbers on the used engine before you buy.... could be a 262, 267, 305 or 350 Chevy V8 . ( all painted GM blue )

The casting number is on the rear of the block on the top by the distributer.

Doug in P.R.:cool:
 
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