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Timing issues, part duex

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tdskip

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Some good news and bad news.

It turns out the drive dog (#83) is not seating properly, so the car will run for a bit and then the dog will come unseated with obvious bad implications for the timing (as-in zero timing since the rotor stops turning).

I pulled the clamping plate assembly (#86) and made sure that it is sitting properly on the dizzy body, but sure enough the drive dog popped out again.

Any ideas for me?

TRS-060.gif
 
Hello Tdskip,

the first thing to check is that the distributor clamp is sitting correctly on the base of the distributor and not keeping it too high. The next is the position of the distributor pedestal. Has it got an extra thick gasket? The third is the position of the drive shaft. I don't have my manual to hand but there is a specific method of setting up the shaft end float. Lastly what condition is the dog and drive shaft? If badly worn it could be lifting the distributor shaft upwards?

Alec
 
If the driven dog (on the distributor shaft) is not seating properly, could it be that you are 180 degrees out of position on the dog in relation to where the the drive dog is on the oil pump? I thought that these had a ramp up on one side being higher than the other, ever so slightly, which would cause a misalignment.

I have several distributor assemblies that I can check as soon as I get home, but that won't be for another couple of hours.

BUT, I am curious if there is anything down in that shaft area of the block that could be interfering at all? Have you looked down there to see that nothing dropped down?

This is not a normal issue with these cars.

Please post back as to what you've found....
 
Hi guys - I can't see any foreign object down there that is preventing the drive from seating.

It is possible I have it 180-degrees out - I'll have to double check when I get home.

Paul - can you let me know what you find when you get a chance to look?
 
This is a completely disassembled unit, but I haven't got the correct picture here to show you.

I will post back as soon as I get home.
 
Hi tdskip, Most of the lucas distributors have a driving dog that is off set from center. If the main drive slot in the engine and the tang on the dizzy do not line up the dizzy will not drop down correctly.--Fwiw-Keoke
 
Part #86 has an up and down to it. Make sure it is oriented the correct way.
 
As Alec and others have said, the drive dog is off set, plus look in your Bentley and make sure you have the proper offset using different thickness gaskets. Is the cast iron pedestal completely seated?
 
Bill that answer makes me wonder something. I just changed to a Mallory unit and drilled a new drive dog on the shaft. Will I have to redo the gasket thickness on the pedestal?
 
To All:

Some interesting views below. If there is a difference in this 22D driven dog, I can't see it. There are however, different clamps as indicated below.

Basing the proper mounting of the clamp onto the distributor, the outer clamp in the picture has lowered portion, so that it would sit up on top of a raised section of the block, as apposed to the clamp on the inside, which shows that is made to sit down into a groove in the block.

I don't know what else to say on this one, other than it is not seating properly in the first place.

bcf-distributor 001 (Custom).jpg


bcf-distributor 002 (Custom).jpg


bcf-distributor 004 (Custom).jpg


bcf-distributor 011 (Custom).jpg
 
One last thing to check. Can you put a long straight slot screwdriver down in the center of the drive cog, on the pump where the round center of the distributor shaft has to fit into and make sure that it is perfectly clean and clear of any obstruction?
 
I had a similar problem after I reversed the clamping plate so that I could loosen the bolt easier, once that was done the distributor would pop up out of the clamp and the drive would disengage. What had happened was when the clamp was bolted down with the bolt in the position furthest away from the block it would not let the distributor seat down far enough because the tach drive housing hit the bolt head. In this instance the drive dog is only partially engaged as well as the clamp. I put the clamp back as I found it and have not had any trouble since.
 
You guys are fantastic - I really really really appreciate everyone's help.

So she is running again. Starts right up - phew. Idle is still a bit lumpy, but I think that is carbs.

Thanks to your help I figured out what was wrong. I had two problems.

1) The dizzy wasn't seating properly into the clamp #86. I had to pull the clamp, clean it, and make sure it was all the way flush on the seat before reinstalling everything. Now there isn't any play in the rotor and the drive dog is tight since the mounting is properly assembled.

2) The big hash mark actually indicates 10-degrees BTC. I had her at closer to probably 12 or 15-degrees BTC, which was just too much for her. Now is is dead-on 10-degrees BTC and she seems to be OK with it.

I still need to do a road test, but I'm cautiously optimistic that I'm good now.

Thanks again!
 
DNK said:
Bill that answer makes me wonder something. I just changed to a Mallory unit and drilled a new drive dog on the shaft. Will I have to redo the gasket thickness on the pedestal?
Click to expand...

I would think if the drive dog is the same exact type as the one on the Lucas, yes. The lash settings have to do with engagement. Too much = wear. Too little = wear.
 
Hi Paul, if you look very closely at the last picture of your dizzy or of your driving dog, you will see that the Tangs are closer to one side than the other. They are not on dead center.---Keoke
 
Ke,

I've got to pull that thing out of it's sealed bag and look at it again. I was tired last night and couldn't see any difference.

TD,

Glad that the pics helped. I purposely put the clamp on the dizzy in the proper position so you could see that it has to fit against the housing.

Now it's time to go out and try to get the wiring fixed for the A/R valve, while it's still warm out. These 12 hour days stink!
 
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