Timing/Ignition Issues

rcassidy · #1 (**permalink**) 01-07-2007, 04:24 PM

A few weeks back I had to replace my intake manifold gasket as there was a small leak at the front of the block. To do this I marked and pulled the dizzy and then reinstalled. I then proceeded to replace the front cover seal (I nicked it a few weeks prior) and then the water pump since that needs to come off to get to the seal. Let it sit for 24hr, filled with fluids and I go to fire her back up and voila timing issues I think. Good news is, no leaks ƒº

The car won't keep timing. I start her up, get her to warm up and idle, set the timing to 18 advance at idle and she runs fine. There is some popping out the sidepipes while the engine warms up, but nothing drastic. Rev her a few times to engage the advance, let off the gas and goes back down to 18 at idle. Then once I shut the car off and start it back up, it goes to 8-10 advance at idle and doesn't idle well, dies most of the time. If I advance it back to 18 then shut off and restart I end up with very high timing (20's) at idle. So then I back her down to 18, shut her off and she¡¦ll start at 8-10 again. This goes back and forth and back and forth again and again. I'm completely stumped.

This is a 427w, Vic Jr Heads, Demon 750 Carb, MSD 6AL, MSD Pro Billet Dizzy, Blaster 2 coil. Let me know if you need more info on the motor.

I have so far done the following:

Checked ohms on all the spark plug wires - In MSD Spec
Checked ohms on the magnetic pickup - In MSD Spec
Re Dielectric grease the plugs/wires
Checked ohms on the Blaster Coil - In MSD Spec
Moved the MSD ground directly to the Block
Pulled the Dizzy to check for play and gear wear. 1/32 of an inch up and down play in the dizzy shaft - No gear wear
Changed Timing Lights
Changed Timing light 12v Source
Checked for crud on the dizzy contacts - None
Opened the rotor to check for burs or something on the advance springs/arms - All Ok
Added 5 gallons (to an already low 6-7 gallons) of fresh 93 octane fuel incase there was some bad fuel
Rerouted a couple wires per MSD's AWESOME (yeah right) tech support to help with possible RFI
Double checked TDC

The only item I haven¡¦t checked is to make sure my balancer is on there (Fluidamper balancer) with the key in the crank. I know it is, but triple checking never hurts.

So this is a VERY long post by now. Sorry, I'm just stumped and short of buying an entire new ignition system I thought I'd put this out to the CC group and see if there are any other ideas to try. There are less that 50hrs on All these components.

BTW the car is in the final assembly process so it's not registered, no seats, and the body isn't on so driving it around isn't really a good option if I could keep from doing that. I'd like to get this resolved prior to putting the body on if possible.

Thanks in advance for any help!!

Cheers,

MaSnaka · #2 (**permalink**) 01-07-2007, 04:58 PM

This may be a STUPID question but is the first thing that came to mind... did you tighten down the dist. after you set your timing?

rcassidy · #3 (**permalink**) 01-07-2007, 06:17 PM

lol.. I knew I was forgetting to mention something. Yes. All tightened down. Dizzy doesn't turn at all. And not a stupid question. :-)

Keep throwing them my way. I'm missing something obviously, hopefully CC can help me identify it.

Cheers,

Rick Parker · #4 (**permalink**) 01-07-2007, 06:41 PM

You may have the distributor off by 1 tooth. It will usually run but will run worse as engine gets temprature and RPM's rise as the rotor moves further out of sync with the distributor towers, this is caused by the centrifical advance mechanism. The other thing may be that you accidently reversed the wires to the distributor from the MSD box. Causing the distributor to be out of phase.

rcassidy · #5 (**permalink**) 01-07-2007, 07:07 PM

Hrrmmm.. Well I checked the wires to the Dizzy from the MSD. The connector is keyed so I'm pretty sure it's on there correct. I'll double check just to be 100% positive again though.

What do you mean by 1 tooth off? If I was 1 tooth off would I not be timed correctly at idle? In this case I can set the timing, it just doesn't stay that way and changes almost predicibly. Hopefully this makes sense. I'm fairly new to this whole carb engine thing. Give me my laptop and I'll have my VW running like a champ :-)

Thanks again for your help!!

Cheers,

HSSS427 · #6 (**permalink**) 01-07-2007, 07:29 PM

Sounds like a good mystery. Just a WAG at someting - is the distributor cap on correctly ie the tab on the cap is engaged with the distributor body?

Also, sound like you had the isssue, pulled the distributor out and then reinstalled it and got the same result, but might not hurt to pull it out and re-install from scratch.

What I do is get the crank turned so that #1 is at 20 deg before TDC. Install the distributor so that I've got the rotor pointing about to where I want #1 connection to be, and then eyeball it so that the rotor and #1 tower are aligned. So now it's set to basically 20 deg advance. Then start it and adjust from there.

It is interesting that something appears to be changing while the engine is off like the advance springs and weights are staying in the advanced position at idle and then when it cools off are pulling the weights back to a less advanced position. You might try it with the heavy springs installed vs a lighter set and see what that does for you.

Other than that, you might see if you could round up another distributor to test it with - might be someone around the area with one laying around you could borrow.

Good luck - believe me I know these "mystery" issues can be frustrating!
Scott

Rick Parker · #7 (**permalink**) 01-07-2007, 08:04 PM

Set the #1 to TDC and remove the distributor cap. The rotor should be pointing DIRECTLY where the #1 plug wire attaches. What you are experiencing is caused by the spark from the rotor being redirected to another cylinder instead of the one your timing light is attached to. That may also explain some of the poping you said you are hearing. Just reset the distributor. You may have to turn the oil pump drive to allow it (the distributor) to drop ito the correct spot.

byron w · #8 (**permalink**) 01-08-2007, 10:30 AM

Hi Ryan,
I think it may one of two things. First, I think it may be in your mechanical advance of the distributor. Second, I think it probably is the fluidampner. They are just not meant for a street motor from what I have been able to learn. I might be wrong. Either way, good luck,
Byron