Dizzy install and timing

B

bmcgc1960

Well-known member
Supporter 2020
I pulled the LOM dizzy and installed a 68 dizzy to match my Holley 1940.

When I pulled the old dizzy I had the engine at TDC on #1 compression stroke.

With the timing marks lined up on TDC the rotor pointed exactly at the #1 terminal on the cap (3 o'clock), the vacuum advance pointed straight back (12 o'clock).

I installed the new dizzy exactly the same way.

The car cranked but would not start.

I ended up installing the dizzy with the rotor pointing roughly at 5 o'clock and the #1 plug terminal on the cap pointing at 3 o'clock. The engine turns over slow and starts, I moved the dizzy until I got a smooth idle.

Tonight I put a timing light on it and the flywheel mark is so far off counterclockwise I cant see it.

I have always had trouble with this task and this time is no different.

Suggestions?
 
Gremlins came when you weren't looking and rotated the engine while you had the distributor out :eek:

If it's idling smooth, runs, drives good, restarts it must be right. When I was 17 and knew nothing I had a hell of a time my first attempt at timing the engine in my car. I didn't mark it when I pulled it. I actually got it to run and somewhat idle, for a while till it backfired out the carb, with it 180 out. But it wasn't "smooth" :LOL:

You could set the timing by vacuum http://classicinlines.com/vacuum.asp
 
I put #1 on TDC and lined the rotor up with #1 plug wire and put in in close to where I took it out. I sat the timing on 12 BTDC.

The 68+ vacuum advance has a nipple vs a threaded fitting for the vacuum line so I had to run a rubber line between the dizzy and carb.

When I run the car without the vacuum line attached to the dizzy, there is no change in idle with or without the line plugged.

Im running dizzy vacuum off the carb, not the manifold, do I need to change that? The pcv valve is running off the spacer under the manifold.

I have a 3-way fitting on the log of my spare engine. I could run the brake booster and dizzy off that and leave the pcv valve on the carb base. Good or bad?

I have the carb off waiting for gaskets, valve stem seals, and an exhaust manifold gasket to come in, should be here anytime.

Im going to try and get the exhaust manifold off without breaking anything. The exhaust leak is so loud that I cant hear anything else under there.
 
bmcgc1960":1ynu192u said:
I put #1 on TDC and lined the rotor up with #1 plug wire and put in in close to where I took it out. I sat the timing on 12 BTDC.

The 68+ vacuum advance has a nipple vs a threaded fitting for the vacuum line so I had to run a rubber line between the dizzy and carb.

When I run the car without the vacuum line attached to the dizzy, there is no change in idle with or without the line plugged.

Im running dizzy vacuum off the carb, not the manifold, do I need to change that? The pcv valve is running off the spacer under the manifold.

I have a 3-way fitting on the log of my spare engine. I could run the brake booster and dizzy off that and leave the pcv valve on the carb base. Good or bad?
Click to expand...

leave your set up as is, the vacuum advance should not come on at idle, but rather off idle, meaning that as you open the throttle to speed up, then the vacuum advance would come on to advance the timing.
 
bmcgc1960":2m813q8c said:
When using vacuum to adjust the carb should I have my gauge hooked to manifold vacuum?
Click to expand...

yes, other wise you get nothing at the gauge.
 
You must log in or register to reply here.
Back
Top