Mk 1 Project Zippy. Looking Like a Car.

[MrBounce]

Everything on the project has ground to a halt until I can sort this out. I have a problem with the backplate/flywheel/clutch arrangement. All has gone on beautifully but when the engine is turned I get a "clunk" about 90 degrees round. It doesn't happen when the flywheel setup is not there (no engine/gearbox issues thankfully) but it's driving me crazy trying to sort it.

Here's a YouTube link to give you an idea of what it sounds like: https://www.youtube.com/watch?v=6a3yzkgb-Ic

[DavidL]

Could it be something unsecured inside the flywheel assembly moving about when you turn it and moving into contact with part of the engine/gearbox casing?
Bit difficult to tell, but you knew that...

[Geoff Butcher]

Can you feel the clunk? And does it happen when you turn it either way?

[wolfie]

I take it you haven't put the starter motor on yet?

[MrBounce]

Nope, no starter on it. Yes it does it both ways. I am thinking that the transfer gears aren't meshing properly. Will know more when I get the flywheel housing off tomorrow.

[MrBounce]

Well, I have found the cause of the clunk and the reasons behind it. The bearing on the nose of the first motion shaft did not mesh properly with the race in the clutch housing. As a result, when the housing was on, the bearing was out under unnecessary strain and parts of it have broken up. Old race + new bearing = unhappy marriage. My fault entirely. A new bearing has been ordered - now I will need to get my hands on a heavy duty blowtorch, a puller and a pair of circlip pliers. All things I don't have to hand.

As a result, I have mostly been preventing myself from burning the garage down this week...

[Rich]

That's a bummer, at least the problem is external to the engine.

[MrBounce]

It's been a while since I went into the Manroom to do anything as I figured the best thing to do was to walk away until I felt like not smashing the place up. I now have my mojo back so it's time to get back in there!

Armed with circlip pliers, a big blowtorch and a new bearing amongst other things, I tentatively opened the door. I'd already managed to remove the clip from the housing, so using an educational video from Guessworks, I heated the housing with the blowtorch for ten minutes then picked it up and smacked it down on a flat piece of wood. It worked first time. Mojo definitely returning. I followed this up with removing the circlip on the bearing and pulling it off the first motion shaft. It was pretty obvious what had happened. The rear of the bearing had broken up and the bits I had found when I'd taken the engine apart were from there. I'll replace the bearing and race next time but I want to clean everything properly first. I have also started work on spreader plates for the mounts for the rear of the front subframe.

Bearing race out - so chuffed that this worked first time!



Damaged bearing almost off...



...and showing the full extent of the damage. So glad I didn't try to start this engine!

[MrBounce]

I had an unexpected couple of hours off today, so jumped at the chance to get into the garage and finish off the engine (again). I had already drifted in the new bearing race into the clutch housing, so that left the new bearing on the first motion gear. This went on with a little gentle persuasion and a new circlip. Having given everything a good clean, I added a new clutch oil seal and once again wrapped up the primary gear. The housing was a bit tight on the dowels so I gave it a little adjustment courtesy of a file, then slid it on with no problem. Then it was simply a matter of once again chucking on the backplate, clutch, flywheel and pressure plate, finishing off with the wok. I have given the engine a good turn and it doesn't clonk anymore. Good!

I also managed to find time to knock up a couple of spreader plates for the front subframe rear mounts - these will need to be tidied up but I can do that on Tink's bench grinder later this week. I'll then give them a coat of paint.

My final job was disassembling the brake master cylinder prior to using a rebuild kit. After cutting through the roll pin with the Dremel I noticed that the reservoir was damaged - it looks like the pin was once pushed into the side of the reservoir. Gotta love eBay... Thanks to a wonderful Mini Forum member, a replacement is on its way. Thanks Phil!

New bearing fitted.



Clutch housing on after a short battle.



Clutch, flywheel & pressure plate back on.

[MrBounce]

Wok tidies everything up nicely.



The engine in all its glory. Again...



Spreader plates cut and drilled, awaiting tidying before paint.