(I think) Timing chain issue... might explain dyno/starting/timing issues..

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finished reassembling her yesterday and... same thing. timing still indicating initial timing at around 45-50 degrees (and will not run below 25... couldn't find an upper limit because the distributor doesn't rotate that far).

could the timing issue simply be that my sparkplug wires are too far around the distributor 1 plug one way or another? It seems strange that the car seems to start and run well enough, but the timing has consistently been off by about 45 degrees or so (ie 1/8th of 360 degress) and that I have to move the distributor as far as it'll go to the left (clockwise rotation) to get it to run right (ie best sound and vacuum).

if so, which way are the plugs probably off?


and... uh.. any other ideas? :-(
 
what is your vacuum doing from the time it starts until it acts up

Well, it immediately 'acts up'. As soon as the engine starts and settles into a normal idle speed (800 rpm or so), vacuum settles to a range of 10-13 psi. When we timed it last night, it made peak vacuum (~16 psi) while indicating roughly 50 degrees initial timing (vacuum advance disconnected). However, at this time it was idling somewhat fast (1200 rpm) and that vacuum figure dropped when we started having it idle slower.

I wouldn't doubt there's a vacuum leak somewhere. My intake and heads are all yellow from something. Like I said, i plan to take the intake off and but a new gasket in and black permatex the hell out of it to make sure any vacuum leaks go away. However, I don't think its THAT huge a vacuum leak, as I can't hear anything audibly amiss. Haven't tried D Hearne's method of hunting for it with choke cleaner (how exactly do you do that? just spray and look for indications? what would you be looking for?).

Really though, I want to get this timing thing settled before I do anything else. Until I know what the timing is doing, I don't think any carb adjustments or vacuum leak fixes are going to help me much.

So yeah... if my spark plug wires were wrong, 1 spot off either way... would that cause my strange initial advance reading and/or be why I have to rotate my distributor as far as it would go in order to get it to run decently?
 
Want to borrow my spare MSD distributor ? =P

I think its time for some beers and wrenches (or wenches).

Always time for beers and wrenches. I've got a shiny new MSD distributor too, remember :D (and i wasted my money on it and the 6AL, my old stocker distributor w/ pertronix and 6A were both fine.. someone's going to get a good deal on that 6A on ebay I guess).

Also... trying to get my buddy's 70 Skylard GS on the road.. if you're down for a real project at some point, let me know. That thing has some serious electrical gremlins :rlaugh:
 
My intake and heads are all yellow from something.
That is leaking gas. Someone else and myself had previously suggested stuck floats. Please check them to eliminate this.

My issue was virtually identical to what you have experienced.

A stuck float will allow the fuel pump to continue to fill the fuel bowl. The extra fuel has to exit somewhere. Usually that is around the baseplate of the carb. Causing a yellow discoloration.

If you hear running water after the engine shuts down that is fuel draining into your intake. That will cause hard starts after the has shutdown. Sometime later the car will start up and run fine until the float gets overpowered again and you repeat the cycle.

It runs better at higher rpm because the engine wants to burn all the extra fuel that you are dumping into it.
 
That is leaking gas. Someone else and myself had previously suggested stuck floats. Please check them to eliminate this.

My issue was virtually identical to what you have experienced.

A stuck float will allow the fuel pump to continue to fill the fuel bowl. The extra fuel has to exit somewhere. Usually that is around the baseplate of the carb. Causing a yellow discoloration.

If you hear running water after the engine shuts down that is fuel draining into your intake. That will cause hard starts after the has shutdown. Sometime later the car will start up and run fine until the float gets overpowered again and you repeat the cycle.

It runs better at higher rpm because the engine wants to burn all the extra fuel that you are dumping into it.

The floats are coming, i swear. There are definitely carb adjustments that need to be made.

Like I said previously, I want to eliminate the timing issue first though. In my mind, if I cannot set the timing for the motor where its supposed to be, all the carb adjustments in the world aren't going to get it to run right. And I'm also hesitant about pushing a high-performance motor when I don't know where its initial or total timing is.

I'll keep my ears open for that 'running water' sound.
 
All the timing adjustments in the world won't make a bit of difference if it won't keep running because it's flooding itself. You can tweek the timing to cover up the flooding. But you will keep chasing timing issues when that isn't the true problem. It's merely a symptom.

My point is that checking the floats will take you 10 seconds to verify. Heck you don't even have to pull the float. Just remove the sight plug. If gas starts pouring out of the hole when running then they are too high. Based on the yellow intake I know they are too high.

If it is the issue I wouldn't be surprised if all your other issues went away. That's what happened in my case.

As for your initial timing being so far off......... I bet your cover and pointer are mismatched.

How much money have you thrown at this to repair?

Fix the simple stuff first and then move on.
 
your timing marks might not line up, which reads artificially high. mine wanted to read 45 deg at idle until i realized it was bogus. check your carb too

Well... I asked about the timing pointers over summer and don't think anyone was able to point me towards somewhere I could find them. I'd think they would be pretty cheap... I'd just buy every pointer type they had and hope one works.

While I'm not 100% sure going back, I was pretty sure that the balancer w/ the current pointer was at 0, when the timing chain was dot-to-dot at TDC. Now that I think about it I may have just checked the dot-to-dot while 'near' TDC without actually putting the balancer on to check. D'oh.

I just combed NPD's catalog and saw no timing pointer. Where can I find them?
 
Is your timing gear cover original? It should be built in, depending on the year.

Is your balancer marked for multiple positions?

Its original to something, not my 66 though (obviuosly, since its a 351w). The engine was an autozone rebuild and had stuff from every year 69-74 on it (70 heads, 72/73 pistons, 69 rods, etc etc) so it'd be tough to tell the exact year.

And yeah, the balancer has 3 sets of timing marks. The one that I've referred to in all of my posts on this subject is the one that matches up closest (and like i said... i 'think' it was pointing near 0 when i was staring at the timing chain at top dead center).

Don't worry guys, the carb will get attention soon. I swear.