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Distributor help needed urgently PLEASE

Joined
Apr 2, 2004
Messages
4,611
Location
Newark, Delaware
Corvette
1965 Coupe L76 / 1978 L82
Hi

I have the 327/365 in my car.
i'm not very knowlegable on distributors and engine repairs so please excuse me if this post seems a bit disjointed or confusing but it's the best I can explain it.

When I bought the car a few months ago I was told the distributor needed to be recurved. I took it to my mechanic - he is the only one who touches my car so far and came highly recommended from a friend who also has a '65.
After replacing the points and trying to recurve and redo the timing my mechanic said he couldn't get the timing set properly because the bushings were worn. As I understand it that means as the timing was changing constantly because of the movement of the shaft because of the worn bushings?
Anyway, since I had the cataloges from the Vette suppliers we went through the Long Island Corvette cat and bought the following:
new shaft (the hi-perf one for the 365hp motor)
springs and weights
baseplate and wire
vacume advance
tach driven gear
lower gear and lower gear pin
upper shaft bushing and lower shaft bushing

Two days ago he rebuilt the distributor with the new parts. Again he said he can't get the timing set correctly. On the first try after setting the dwell (with some meter) and than setting the timing with the timing light we drove the car and it wouldn't get out of it's own way and it sounded really bad. He immediatelly said it seemed as though something on the front of the engine "slipped" (maybe a harmonic balancer - I'm not really sure or can't remember what he said exactly) but that he could probably get the timing set by ear and by driving the car.
After almost another 2 hours of playing with it it's SLIGHTLY better than before we started with all the new parts but barely. Previously, the car would rev to 6000rpm than the engine just wouldn't go any further. Now it will go to about 6300rpm but still no further. Also, low end torgue is not what I think it really should be.
I really don't rev the engine up very hight when i'm driving it but I DO want everything to be right and everything set correctly regardless.
Now he tells me we need to get a new "vibration dampener" and that will allow him to properly get the timing set correctly.
Does this sound correct???

The first time I took the car to him was for the distributor recurve (and a few other things). That was $300 and I still left without proper timing. Than I got the parts which cost me over $200 from LICS and than the labor charge again the other day of $270. I've already spent almost $800 and it's still not right and calling around locally this "vibration dampener" runs about $70 and it will be about 1.5 hours labor to install for another approx $112.50.
Am I wasting my time (and more importantly my money!)? What's going on here?
Please Help!

Barry
 
the balancer or vibration dampners do slip which causes the timing mark to be in the wrong place your engine being an early has a high compression ratio by todays standards and the timing needs to be set correctly or it will detonate if too far advanced. the way I like to set timing is to first determine TDC to see if your mark is correct then with a timing tape mark the balancer for the total advance and set the timing that way.
someone with more experiance in using these older high compression engines on todays gas can fill you in on the proper setting.
I had one (dampner) slip 8 degrees and it gave me fits untill I figured it out.
 
bossvette said:
the balancer or vibration dampners do slip which causes the timing mark to be in the wrong place your engine being an early has a high compression ratio by todays standards and the timing needs to be set correctly or it will detonate if too far advanced. the way I like to set timing is to first determine TDC to see if your mark is correct then with a timing tape mark the balancer for the total advance and set the timing that way.
someone with more experiance in using these older high compression engines on todays gas can fill you in on the proper setting.
I had one (dampner) slip 8 degrees and it gave me fits untill I figured it out.

thanks Boss, at least this tells me that what he says about this balancer slipping is legit. Guess I'll have to get this part and have him try it once more

Barry
 
warren s said:
Its time for a new mechanic.


Warren

He did come highly recommended by someone I do trust and whose car he also worked on. Also, I really don't know anyone else in the area I'd trust to touch my car. It's not like I'm going to take it to the local Chevy dealer!
I guess I'll get the balancer and see what happenes after he installs it. If it's still not right after than than I'll have to search around for somebody else.

Barry
 
Lets see, its been a long time, and being a computer mechanic let me see if i remeber how i would do this.

If the balancer doesnt have the correct timing mark lined up with the pointer because its slipping, or slipped - I would line up the ignition rotor with the number one piston at top dead center (pull the plug, insert pencil after tapping the ingition key to see where the piston is.) You could also pull of the valve cover but thats a job to itself. I would put a chalk mark on the balancer to indicate where 0 degrees is about.

5 bucks in most speed shops for "timing tape" if they still make it, and 59 bucks for a Sears Advance timing light with the dial on it.

assuming the balancer is slipping and the distributer may have issues, i would not be revving the motor out to 6000 anyway until both were rebuilt or replaced. Actually I would go with a breakerless MSD unit.

Anyone??? Am I on the right track??
 
warren s said:
Actually I would go with a breakerless MSD unit.

Actually, I had considered doing the Lectric Limited electronic conversion kit initially but than decided I wanted to keep things stock - at least for now. I'd rather get the distributor and timing all set properly first with it in stock condition and that way I know everything is proper and correct.
Afterwards I could always have the electronic conversion done for better reliability.
My mechanic did say previously if we did the electronic conversion I wouldn't have had to had the entire distributor rebuilt with the new bushings, etc because the slight shaft play wouldn't have affected the electronic ignition like it does with the points. I choose this route simply because in my mind I felt that doing it the other way was just masking the other symptoms even if it would work - fact is I would still have had worn out parts in the distributor. Maybe it was a mistake and maybe I'm just too anal about things but i'd rather get the car working correctly using correct & proper parts for it before going to a "modern" upgrade to fix it. It ran fine when it was new without electronics so it should be able to run fine now the same way.
Or maybe I'm just an idiot.
:confused
 
Barry -

Talking about taking an origional condition mid-years and making modifcations is like talking about religion and politics, could be very risky!

Just remeber that what ever you do, just dont throw out the old parts. Going to electronic ignition would have many benefits. Cost and performance being the main ones.

I am just surprised your mechanic didnt mention then to you, unless you made it clear you wanted to stay completly stock and origonal.
You would be surprised how much "finer" it would run.
 
I basically agree with bossvette. I would find TDC on #1 as he described remark the balancer as needed reset the timing and verify that this is the problem BEFORE replacing any more parts. And no you're not an idiot... it's just that hind sight is 20-20
 
warren s said:
Barry -

Talking about taking an origional condition mid-years and making modifcations is like talking about religion and politics, could be very risky!

Just remeber that what ever you do, just dont throw out the old parts. Going to electronic ignition would have many benefits. Cost and performance being the main ones.

I am just surprised your mechanic didnt mention then to you, unless you made it clear you wanted to stay completly stock and origonal.
You would be surprised how much "finer" it would run.


Warren

reread my post, we DID discuss going electronic and he actually recommended it. i'm the one who decided (for now at least) to keep things stock. I'd rather get it running properly using correct parts BEFORE changing to electronic. that way I'm not just masking what is still an underlying problem.
And yes, when he rebuilt the distributor I did keep all the old parts even though they are worn out. i'm sure old, worn distibutor bushings and gears are worthless to anyone but I have them in a box anyway.
 
studiog said:
I basically agree with bossvette. I would find TDC on #1 as he described remark the balancer as needed reset the timing and verify that this is the problem BEFORE replacing any more parts. And no you're not an idiot... it's just that hind sight is 20-20

ok, remember please that I really don't know anything about this...
are you saying that he should be able to correctly time the car by marking the balancer without actually replacing it??
If that's true I'd be surprised if he wouldn't know this but I can mention it to him.
 
One more thing... Is your mechanic sure he didn't reinstall the distributor off a tooth from where it is suppose to be?
 
BarryK said:
ok, remember please that I really don't know anything about this...
are you saying that he should be able to correctly time the car by marking the balancer without actually replacing it??
If that's true I'd be surprised if he wouldn't know this but I can mention it to him.
Yes that is what I am sayimg. When the #1 cylinder is at TDC on compression stroke the timing mark should be at 0 degrees on the scale if it is not make a new fresh white mark at the 0 degree mark on the balancer. Then retime the car.
 
studiog said:
One more thing... Is your mechanic sure he didn't reinstall the distributor off a tooth from where it is suppose to be?

good point, I forgot to mention this...
he suspected from the first time he looked at it that it might have been one tooth off. he found after he pulled it the other day that it was already installed one tooth off. He thinks the previous owner did that on purpose to compensate somehow because everything else was so far off that when installed correctly it was actually worst.
After he rebuilt it and reinstalled the distributor he made sure it was proper and not a tooth off but it was still SO bad he again had to go back to put it a tooth off just to get it to run as it is now. With it installed without being a tooth off it runs like crap.
He said his plan was for me to get the new vibration dampener, install that, than reinstall the distributor correct again to see if everything works itself out.
 
He could also make sure the distributor is right by turning on the ignition to on (not start) & removing the plug wire from the #1 plug holdng it close to ground then rotate the distributor till the coil fires (a spark jumps to ground.) This will give you a starting point to make your adjustments and to be sure the distributor is in the right spot.
 
studiog said:
He could also make sure the distributor is right by turning on the ignition to on (not start) & removing the plug wire from the #1 plug holdng it close to ground then rotate the distributor till the coil fires (a spark jumps to ground.) This will give you a starting point to make your adjustments and to be sure the distributor is in the right spot.

As much as I want to trust this mechanic since he was recommended to me by someone I trust, I'm starting to agree with Warrens first response.
it may be time to find someone new.
As I've stated I don't know anything about this stuff but what you and Warren mention seems to be fairly basic things that he should have done (if he didn't which I really don't know). If he DID do them I imagine the car should be running correctly. If he DIDN'T do them than he may not be as good as I was led to believe.
Sigh! :(

Actually, there IS a corvette specialist about 25 minutes from me called County Corvette. They have a very good reputation but their shop labor charges are pretty high but after all the money i feel i've wasted at this point no sense throwing more away. It may be time to try this other place even with their higher prices to see if they can at least get it right!

I wish i had the knowledge and tools to do the job myself and save all this money but I'm mechanically challanged when it comes to cars. LOL
It would be great to be able to do the work on the car myself as many of you do and save all the money I have to spend each time something goes wrong.
 
Please let me offer some food for thought.

The outer ring of the harmonic balancer won't simply "slip" around the balancer centerline. That's an old wives' tale. Some bad things CAN happen to a balancer. A pressed-on harmonic balancer hub can come off the end of the crank. The outer ring can shatter and spread shrapnel all around the engine compartment. However, the outer ring won't ever "slip" around the center hub of the balancer. If the elastomer between the hub and outer ring starts to fail (usually after some idiot has soaked a balancer in a solvent tank), the outer ring may walk a little towards the rear of the car. But it still won't rotate around the center hub.

People who think they've encountered a "slipped" balancer ring have actually just discovered a balancer that is mis-matched to the engine timing tab. Chevrolet has put the timing tab on small blocks in at least 4 different locations since 1955. The balancer TDC mark is located differently for each of these timing tab locations. If you take a 1970 balancer and install it on an engine with a 1964 timing cover, you've got a 10 degree mis-match, not a "slipped" balancer ring.

As far as the distributor being installed "one tooth off", you can stop worrying about that. Your only concern is that the vacuum canister has enough room for rotation to properly time the engine. With a mechanical tach drive, you should also make sure the the tach drive cable doesn't have any sharp bends in it too. Other than these two concerns, there isn't a wrong tooth if your timing light says everything is fine.

You've gotten some good advice here. Step 1: Check the location of the balancer TDC mark USING A PISTON STOP TOOL to make sure it's coordinated with the timing tab on your engine. Step 2: install a timing tape on the balancer (or mark it with chalk) so you can make sure the distributor advance mechanisms are working properly. Step 3: Set the initial timing at a low idle speed with the vacuum advance disconnected. Make sure the mechanical advance hasn't begun to affect the timing at this idle speed. Also make sure the dwell of the points is set at 30 degrees BEFORE you set the timing. Step 4: watch the timing change as you rev the engine to make sure the advance mechanisms are working.

To find true Top Dead Center you must use a piston stop installed in the #1 plug hole. You can't place the balancer mark accurately by guessing "about" when the the piston is at the top of its travel. If your mechanic doesn't know how to do this with a piston stop, then find a new mechanic.

As far as electronic ignition is concerned, you should put off making any more changes until you've gotten the basic timing correct. Why give yourself another unknown to deal with right now?

One other thing. Please stop revving your engine to 6,300 rpm to see what will happen. If your engine isn't running right at low rpm, it's not likely to run right over 6,000 rpm, is it?
 
BarryK said:
As much as I want to trust this mechanic since he was recommended to me by someone I trust, I'm starting to agree with Warrens first response.
it may be time to find someone new.
As I've stated I don't know anything about this stuff but what you and Warren mention seems to be fairly basic things that he should have done (if he didn't which I really don't know). If he DID do them I imagine the car should be running correctly. If he DIDN'T do them than he may not be as good as I was led to believe.
Sigh! :(

Actually, there IS a corvette specialist about 25 minutes from me called County Corvette. They have a very good reputation but their shop labor charges are pretty high but after all the money i feel i've wasted at this point no sense throwing more away. It may be time to try this other place even with their higher prices to see if they can at least get it right!

I wish i had the knowledge and tools to do the job myself and save all this money but I'm mechanically challanged when it comes to cars. LOL
It would be great to be able to do the work on the car myself as many of you do and save all the money I have to spend each time something goes wrong.

I hate to pass judgment on anyone without knowing all the facts but I think it is a good policy to do your best to throughly diagnose the problem starting with all the basics before you start replacing parts. I'm sure you will get it resolved. A second opinion sounds like a good decision right now. Good luck.
 
Sounds like it's time to move on to a new Mechanic...No disrespect intended.

Were talking about 60's tech..Points & basic timing set up. Any good mechanic should be able to figure out this problem with this simple 60's tech ignition if he is familiar with a points type system.

The motor must be diagnosed in the proper order to eliminate other items that could be causing the problem. There is a valve trane to consider also as well as other items. I think your on the right track with county corvette..

Good luck and keep us posted on your progress. I'm sure we would all like to know what the final problem was for our own future troubles.:beer
 
Jerry

thanks for the great info!
that's going to be handy to know.
I'm going to take the car to this other place instead of the guy I've been using

Barry
 

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