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Discussion Starter #1
Ok so I verified that there is indeed some kinda problem. My engine does not idle properly at the specified timing according to the mark on the ballencer. I was told these old ballencer's were rivited together and couldn't slip. They only go on one way.. What is going on here? I will verify TDC with a chopstick or piece of copper wire or something I can fit in the #1 spark plug hole.

The mark is probably 20 degrees off of where it should be if I have it timed right by ear and vacuum.

I AM using "regular" gasoline if that makes that much of a difference.

The engine is a rebuilt 283 stock harmonic ballencer and cover.. It should line up.

-Tom
 

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Discussion Starter #2 (Edited)
I checked the mark with a piece of wire and by when the air stops coming out.. It IS correct. Could they have put the cam in wrong?

Am I trying to time it with the wrong idle? I had it at 700rpm. 4 degrees seems waaaay too low and the engine runs awful there. It runs nice way off the scale. I have a pertronix ignitor II which is kinda like an HEI. I gapped the spark plugs a little wider than stock could this be why?

-Tom
 

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You sure you have the #1 plug wired to the correct spot on the disti? You're not off by 1 position all the way around, and compensating for it by turning the timing back the other way?

When at TDC, pop the disti cover off. Is the rotor pointed at what you think is the #1 plug wire?
 

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Discussion Starter #5 (Edited)
I have verified the engine is at TDC I took the distributor cap off and :



The blue tape is where spark plug #1 is.

This is where it seemed to idle the best and have the most vacuum I didn't play with it nothing.

Does this look right or is something way wrong like cam in the wrong spot?

I'd take the valve cover off but its like they welded it on so I'm a bit reluctant too.

-Tom
 

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Discussion Starter #7 (Edited)
It had occured to me. The indent for the cap's hold down clamp can be seen in the picture.. just to the left of the rotor. It (the indent) is exactly in the middle of #1 and the next plug in the firing order.

Could my timing chain be off a tooth or is this purely a distributor issue? If I time it to 4 degrees btdc per chevy's spec its loud and sounds like compression is coming out of the carburetor. Almost sounds like a deisel and I get like 12 vacuum and a drop in rpm.
I don' know if is normal for a v8 engine to sound like that if the timing is too retarded I've only dealt with my 6er.

-Tom
 

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To determine true TDC a piston stop is needed. To set timing properly an accurate timing light is needed. Dampeners were never riveted together, they need to allow the outer ring to absorb and dampen the vibrations of the cylinders firing which is done by the it moving slightly against the elastomer strip between the hub and the ring. If your timing chain is off a tooth the engine will have no power but most times it will idle smooth.
 

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If the piston is TDC and the distributor is there seems to be off a tooth or two. When you built it did you degree the cam? As others have said use a piston stop. I have used a cheap led flash light with a flexible neck to look in the plug hole as someone turned the crank. Just a caution don't use the harmonic balance bolt.
 

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Is the rotor pointing to the firewall? If so restab it 180 degrees and have the rotor point to number 1 cylinder. It looks like you are off on your timing and stabbed opposite of where you should be. Not 180 out just stabbed backwards. If you have the engine at TDC #1 and rotor pointing to number 1 it will be much easier to get timing set. Just my 2 cents.
 

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Discussion Starter #12 (Edited)
If the piston is TDC and the distributor is there seems to be off a tooth or two. When you built it did you degree the cam? As others have said use a piston stop. I have used a cheap led flash light with a flexible neck to look in the plug hole as someone turned the crank. Just a caution don't use the harmonic balance bolt.
I did not build the engine it was built by a reputable shop.. I assumed they did. But I think they messed it up. Its not 180 out cause the car runs and drives. I don't know how much power its supposed to have but it seems to have alot more power than the 6 cyl did but ONLY if I ignore the timing light completely otherwise it sounds like a deisel engine.

I ordered a piston stop from summit but it'll be awhile before it gets here.. It seems to me if the balencer had slipped it'd be wayyyyyy off cause I was around 20 degrees advance with thee light and it seems to be either dead on or very close just based on m observations. 3 or 4 degrees off isn't going to make the timing jump by 20.

I'm leaning toward a tooth or two off.. The shop is 8 miles away at 25-35mph. I ran out of money for towing.. It seems to run and drive smooth. Should I just drive it to the shop and have them figure it out? I just don't want to break something if there is pre-detonation.

How can I check cam timing?
-Tom
 

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I did not build the engine it was built by a reputable shop.. I assumed they did. But I think they messed it up. Its not 180 out cause the car runs and drives. I don't know how much power its supposed to have but it seems to have alot more power than the 6 cyl did but ONLY if I ignore the timing light completely otherwise it sounds like a deisel engine.

I ordered a piston stop from summit but it'll be awhile before it gets here.. It seems to me if the balencer had slipped it'd be wayyyyyy off cause I was around 20 degrees advance with thee light and it seems to be either dead on or very close just based on m observations. 3 or 4 degrees off isn't going to make the timing jump by 20.

I'm leaning toward a tooth or two off.. The shop is 8 miles away at 25-35mph. I ran out of money for towing.. It seems to run and drive smooth. Should I just drive it to the shop and have them figure it out? I just don't want to break something if there is pre-detonation.

How can I check cam timing?
-Tom
Rotate the engine to #1 both rockers on 1 should be closed
Have you tried a different timing light ? Last vehicle I did said it was 76 degrees BTDC got a new light and it was at 10
 

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Discussion Starter #14
Rotate the engine to #1 both rockers on 1 should be closed
Have you tried a different timing light ? Last vehicle I did said it was 76 degrees BTDC got a new light and it was at 10
I have not tried a different light.. I only have the one but it is only a few years old. A friend has a dialback light I will see if he can help me out.

-Tom
 

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Discussion Starter #15
I'm 80% sure its off a tooth or two. Talked to an old timer and he told me the same thing. Its just not right.. I am having the car towed to the shop that built the car Monday. Its just not supposed to sound like a deisel at 12 degrees and if the balencer was off 30 degreess it'd be more obvious.

This was why it was so hard to set the timing to start it to break the cam in!!!

Guess I will know for sure on monday!

-Tom
 

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Tom, most of the time a small pen light and a mirror and you could probably see the piston in the cylinder... TDC both valves on #1 are up (valves closed, springs up) as you spin it over by hand you can watch the valves and pause and look into the cylinder... or with a short thin wire you can feel the piston rising. gentle gentle, don't be man handlin' it and lock it up with something in the cylinder... take your time. is the dampner new or is it your original unit? how old is it? new timing cover or old one? is timing tab the same old unit or is it new?

get a timing light, even a $25.00 light could last you forever...
 

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I'm 80% sure its off a tooth or two. Talked to an old timer and he told me the same thing. Its just not right.. I am having the car towed to the shop that built the car Monday. Its just not supposed to sound like a deisel at 12 degrees and if the balencer was off 30 degreess it'd be more obvious.

This was why it was so hard to set the timing to start it to break the cam in!!!

Guess I will know for sure on monday!

-Tom
What is the distributor ? If so you can set TDC like others said then once you are sure piston and valves are TDC pull the distributor and move it one tooth towards we're 1 is on the cap
 

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Keep in mind it is a 4 stroke engine and the piston is at top on two of the strokes. Make sure it is on the compression stroke and not the exhaust stroke to get TDC.
 

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Discussion Starter #19 (Edited)
Tom, most of the time a small pen light and a mirror and you could probably see the piston in the cylinder... TDC both valves on #1 are up (valves closed, springs up) as you spin it over by hand you can watch the valves and pause and look into the cylinder... or with a short thin wire you can feel the piston rising. gentle gentle, don't be man handlin' it and lock it up with something in the cylinder... take your time. is the dampner new or is it your original unit? how old is it? new timing cover or old one? is timing tab the same old unit or is it new?

get a timing light, even a $25.00 light could last you forever...
My timing light is new and seems to be working it is not flashin iradically. I used a small piece of welding rod I had put a little rubber bumper on that I had laying around in the cylinder to determine TDC. The dampener is correct to within 4 or 5 degrees. If I retard the dist towards #1 and try to start it she shoots fire balls out of the carb. If its running and I do this it sounds like a diesel engine and pops out of the carb. I have to bring the car back anyway to have them fix a broken carburetor stud they forgot to replace when they rebuilt the engine. Already found a local tow truck that will bring it there for really cheap and the shop said they'd take a look and help me dial it in for free. Its still under warranty.. I would just take the valve cover off and watch the valves but I'm tellin you they just about welded the covers to the block. I already bent it up a bit tryin to get it off. This way if something is wrong he'll tell me and they will have to fix it since its under a 6000 mile warranty if nothing is mechanically wrong he can just show me what the deal is and I'll have the piece of mind but be out only the towing charges which isn't bad... I think this is the safest route. I always seem to break stuff like this when I don't understand it.

-Tom
 

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sounds like the dist is stabbed incorrectly... the oil pump rod will possibly need to be rotated in order for dist to drop in at the right spot.

you took it into the shop you said? they should have it back to ya shortly i'd suppose. ;)

don't worry. ;)
 
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