a couple of issues
Turbo Mini Forums

I managed to get a few hours to myself this morning and stripped the box off the mini turbo engine and came up with a couple of issues;

1) the primary gear bush has 'discoloured' a fair bit and there is some colouration on the crank. On closer inspection, the gear has some play on the crank. without the lock washers fitted. I fitted up another primary gear I have ant it was a much tighter fit however the standard helical gear I intend to use had similar play to the one taken off. Now when I say similar, this was measured by the technical method of holding it and moving it about - no thing more technical!

The crank and gear were brand new so should have had no previous wear. Your thoughts? (and apologies for the crap photos, they were takwen on the phone)



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Also noticed the end of one of the oil jets has broken off (piston 1). No witness marks so will have to do a bit more research and find the missing bit

Is that a bimmer Jet? I had to space mine with a couple of copper washers.

jets are the ford ones

I had to notch the bottom the piston skirt for clearance when I fitted the Zetec jets as the piston skirt just poked out the bottom of the bore enough to hit them.

Is the crank a hardened item and were the primary gear journals polished like the mains and big end journals? Also, did you lubricate the primary gear bearings before fitting? I've had similar, but close on total bush failure, that was down to the coating left on the tail of the crank from the hardening process. It was left on there so I just ran with it, in the thinking that if it wasn't supposed to be there, they would have polished it like the other journals.

I use some wheel bearing grease on the primary gear bearings at assembly, and It's still been there when I've taken it apart suggesting the actual flow of oil to that part of the engine is negligible which is what you want really. Oil flow tends to increase when there is play in the bearings of the primary gear though. I'd thoroughly recommend the floating bush and have the rear top hat re bushed and sized to the crank tail., and lastly, make sure the primary gear is properly shimmed and use a good used original 'C' clip from an old engine. Some say that setting the end float clearances on straight cut transfer gears isn't important, well I beg to differ

Just another thought. were you using the sintered paddle friction plate? those dump more heat into the primary gear as the friction material is of metalic origin, and more conductive to heat than the organic plates

Edited by Sprocket on 2nd Feb, 2014.

Wheretic heck valve in the jet? Is it in the main body or will it now spray all the time no matter the pressure?

I suppose Its a strip down the make sure the others are ok /require spacers anyway?

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

the valve is in the body

cheers Colin; yes I was using the sintered plate and did have a fair bit of judder so just wondering if that was a contributing factor; In all honesty, I can't recall I applied lube on assembly or not - its been a while.

The crank was a brand new one supplied by minisport a few years back. I'm assuming it would have been one of the MPI batch kicking about

The drops are going into the metro so I'll trial fit them on the other engine before I decide what to do with them. As for this unit, I'm replacing the clutch plate with something a little more suitable for the car and road