timing jumping = impossible to set (type 4)

Post by **Tony Z** » Thu Jul 13, 2017 7:51 pm

disconnect vacuum hoses and plug them before setting the timing with a light.
Do this and check your timing again, maybe you are only seeing the effects of the vacuum advance?

marcw · Post by **marcw** » Fri Jul 14, 2017 2:33 pm

Ok did the check play procedure on the distributor drive and there is very little difference through the cycle. There is however some 1mm play on the drive. There are times when I can make the ding, ding, noise quite specific and others where it is not so noticeable. This may just be oil on a particular place on the gear.

The interesting thing is that the play is about 1mm, is this high?

How much play is too much on the timing gear and distributor drive?

Last the ding I hear by moving the distributor drive back and forward is very similar to the ding I hear when the engine is running.

I think my ding noise comes from the distributor drive. How do I check this thing?

marcw · Post by **marcw** » Fri Jul 14, 2017 2:34 pm

Oh, and have done all timing with two different lights and always with the vaccume hose disconnected and plugged.

marcw · Post by **marcw** » Sat Jul 15, 2017 7:29 am

My last question on the matter before I bite the bullet and tow Bella to Pierre.

What should the play be on the distributor drive to the drive gear on the crank? How much is too much?

Dawie · Post by **Dawie** » Sun Jul 16, 2017 10:34 pm

There will be some play. Which should not affect timing if everything runs very smoothly as it should, because the slack is taken up while running.

Could the crank gear have some damage from being removed/ refitted? Or the Distributor drive turning slightly more difficult in certain spots?

Then it might be dancing up and down against the spring's pressure. The crank gear is turning clockwise, so it will try to lift the distr drive each time too much force is needed to turn it.

While turning engine, you mentined this:
" There are times when I can make the ding, ding, noise quite specific and others where it is not so noticeable. This may just be oil on a particular place on the gear. "

That little spring... are you 100% sure it is the correct type- (pressure and length?)

marcw · Post by **marcw** » Mon Jul 17, 2017 10:56 am

On the spring type - I have no idea at all - all I know is it fits

That's a good point actually.

The drive went in fairly difficult to start and then towards the end went in easy. Maybe the clearance between the drive and its casing hole is too close.

All this needs a drive puller to check. Hopefully will have one today.

Dawie · Post by **Dawie** » Mon Jul 17, 2017 11:57 am

First of all i would check the spring to see if it's the right one. If too weak or too short it will cause problems.

If you have to withdraw distributor gear there is a good chance that the washer/spacer will fall out. I would tilt the engine to have distributor and it's drive in a vertical position before removing the drive.Otherwise the washer, being oily and slippery, will just slide down.

Terry Phillips · Post by **Terry Phillips** » Mon Jul 17, 2017 2:29 pm

If my memory serves me right you need a adjustable timing.Rev it to 2500 rpm measure it back to zero TDC vacum pipe off will give you your timing.
The difference between centrifugal minus the reading with the pipe back on will give you your advance degree.if that helps. I have not read all the post but you might have done this procedure.

Terry Phillips · Post by **Terry Phillips** » Mon Jul 17, 2017 6:22 pm

Have you checked the crank pulley key way not worn or loose.

marcw · Post by **marcw** » Mon Jul 17, 2017 6:40 pm

Thanks Terry - yes I have been through the timing process to set to 7.5 BTC at idle and 28 at 3000 rpm. The problem is that the timing mark is hunting through about 10 degrees - 5 degrees each way. Hence I cant set the timing.

On the crank pulley key, I don't think that is the problem since the engine when running is missing. When the jump forward 5 degrees happens there is a noticeable missfire on the engine. The same when it dips back 5 degrees. So it is not a reading error because the engine is actually feeling the miss on the wandering timing.

I will be pulling the distributor drive tomorrow when I have the tool. Holding thumbs that the washer/shim at the bottom does not fall into the sump. That would just be the cherry on top of this issue.

Terry Phillips · Post by **Terry Phillips** » Tue Jul 18, 2017 12:17 am

Put the pulley on what ever degree you want it, turn the ignition on turn the dizzy until you hear the points spark and thats it timing should be close. again if you have not already tried this method.

marcw · Post by **marcw** » Tue Jul 18, 2017 1:42 pm

So thanks to Calooker I have a distributor drive puller. The thing worked perfectly. Very many thanks. The shim came out with the drive.

First remember that I have two of everything which means I am able to check parts from one engine with those from the other. The other engine was running well until a main bearing next to the fan seized up solid. (Number 4 I think it is. The one next to the timing gear and the cam gear.)

- The drive did not come out easy at all. In other words the hole it goes in is exactly the same size as the drive with ZERO play at the top end.
- The 2nd motor distributor drive goes in with a tight fit but much easier.

- The fins on the drive current being used have some places where there is no wear at all.
- The fins on the spare drive are all smooth from wear.

- The drive shim (the one between the drive and the case) is also wearing on very specific spots and not even all the way round as if both surfaces were flat.

- the 'dog' that goes into the drive is thinner on the one dizzy compared to the other which is a snug fit.
- I have tried both and there is no difference between them so I presume that the engine revolutions and the inertia on the dizzy keep them together and the loose fit makes little difference.

I have included pictures of all these below.

Dawie · Post by **Dawie** » Wed Jul 19, 2017 2:54 pm

Looks like the one on the left (middle picture), could have lived outside of it's engine at some time and grew some surface rust, making it bigger.
Or maybe there was water in the oil at some stage...

marcw · Post by **marcw** » Wed Jul 19, 2017 3:05 pm

Lived in my back room for many years. I put the wrong one back in the engine.

Post by **retrovan** » Thu Jul 20, 2017 10:50 am

Maybe you should look at earths 1st, make sure the engine is earthed as this sounds like and spick and an electrical issue as the mechanical can not react that fast.

This may even be a loose connection on your alternator, that spicks the voltage, maybe fit a multi tested and see.

Not sure if I read if you have tried a new dizzy cap. ??

Herman

Aircooled VW South Africa

timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)

Re: timing jumping = impossible to set (type 4)