16 replies to this topic

[scoop-face]

Hi guys.
I’m rebuilding my A+ 998 engine.
It has a new 266 cam all timed in and ready for the dizzy drive to be inserted.. Iv followed all the steps of cylinder #1 at TDC, insert the drive at 1 o’clock / 7 o’clock but the drive doesn’t mesh with the cam.

Does anyone have any advice or suggestions?

Any help would be appreciated! Iv spent hours trying to wiggle it in to place with no luck!

[Ethel]

Is it built up or still in bits on the bench? If the latter you could try without the cam installed

[cian]

Rock the flywheel back and forth slightly

[DeadSquare]

Remove the insert in the block, into which the dizzy is fitted and try it;  this gives you a bit of "wiggle room"

 

Presumably you have screwed a bolt into the outer end to hold on to when trying to insert it ?

 

BUT

 

Tie a length of string round the bolt in case it drops into the sump.

[Spider]

They can be a fiddle to fit between the con rods when the engine is at TDC, I usually wind them over a few degrees.

 

If it's the drive gears themselves you can mesh exactly at 1 / 7 O'Clock, be aware, initially, the need to be around the 3 / 9 O'Clock, then as the helix of the gears turn the drive as it slips in, it will end up at 1-7 O'Clock-ish, a bit either side of that is OK.

[scoop-face]

Thanks for the replies.
It’s more or less fully built on the bench.
Iv got a bolt threaded in to keep hold and give it a wiggle as I insert it.
I have been installing it at 3-9 and it does slot around a little bit to 2-7ish but doesn’t mesh properly at all, as I turn the engine over by hand it rotates a few degrees then locks or binds tight as the teeth don’t want to mesh.
It’s very frustrating..
I am considering removing the cam and installing them both together...
but everything Iv read suggested this shouldn’t be necessary..
It’s all A+ components.
Iv literally spent a good few hours turning the engine and wiggling away with the drive... with zero success!

[DeadSquare]

By "More or less fully built", do you mean, bolted to the gearbox ?

[scoop-face]

Yes the gearbox is installed. I only need to install the electrics. Dizzy drive, dizzy, leads and plugs. All the rest is built.

[Ethel]

I've never really had a problem, once I've managed to wiggle it past the crank.  Removing the timing chain, backing off all the tappet adjusters fully and/or removing the push rods could give you some useful wiggle factor.

 

Could it be bent or burred on an edge? Forgetting about the correct slot alignment and trying different rotations could reveal that sort of issue.

[DeadSquare]

Before you pull the cam, try taking the collar out of the block;  it gives you a bit of an angle to shine a light in and see if the might be something in the spigot hole that is stopping the dizzy drive from going in the full depth.

[gazza82]

Silly basic question, but it is an A+ drive shaft? Older A type is different

[MiniMadRacer]

Good call there gazza, like most here I have "tons" of old / used spares kicking about (I never throw anything away, unless clearly foo barred) and I could kick myself the amount of times I have picked up 998 parts for a 1275 or vice versa and A parts instead or A+ and vice versa. Soon becomes obvious when you try to "cross fit / mis match" but it is still frustrating  / annoying with oneself having done it 100s of times....

[scoop-face]

What do you mean by “collar”?
When I pull the drive out I can see straight through to the spigot hole - which looks fine.
There seems to be enough clearance for the drive when the crank rotates and the piston moves down the block.
Yes it’s the drive that came out of the block before I rebuilt it.
Iv got the old standard cam, the drive and old cam mesh perfectly.

[scoop-face]

I’m starting to doubt myself now..
I do have a 1275 block and parts laying around..
Would there be a difference between a A+ 1275 dizzy drive and a A+ 998 dizzy drive?

[Spider]

What do you mean by “collar”?

 

As yours is A+, it doesn't have one, but in any event, I'm not too sure how one could be fitted on an earlier engine with the Collar in place?

 

I’m starting to doubt myself now..
I do have a 1275 block and parts laying around..
Would there be a difference between a A+ 1275 dizzy drive and a A+ 998 dizzy drive?

 

These are the same between them.