How to check big/small ends?
Turbo Mini Forums

I'm splitting my box/block this weekend (thanks to Tom for the flywheel puller!) - is there a reliable way to check the big/small ends when they're apart, or do i have to strip the block down?

:)

take the crank out and then the rods and pistons and ask morespeed t check them mate

i know the small ends def need doing so the rods will need bushing at an engineers anyway

that sounds way over my head!
im just thinking that it might be worth getting another bottom end, and using the box / head from you, and a regular bottom end.. might work out cheaper.

Alex,

what is the history of the engine? - ie is it a non runner, is this strip a precautionary measure, is the engine a smoker, etc...

What are your plans for THIS engine? - this dictates what you need to do. for example - I get the feeling this is the 'first' turbo engine you're putting in a mini, and that it'll be a 'fun' car with a bit of speed, but needs to be kept reliable(ish)?

D

What engine is it ?? because i'm not sure why it needs the small ends doing and how you know this already with out stripping it.
You can check the big ends and the cap side of the mains very easy once you have the box off but getting to the block side of the mains isn't that easy without taking the cam gears off.

Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

I think you can do one at a time doody? Even so - lifting the mains and big-end caps will reveal if further work will be needed - I hope not!!!

We need more info Alex!

I'm never keen on trying to get the blockside mains out with the crank in place, i always find the cam ends a bitch to get back in unless the (Belt) in my case is removed. I do agree though one at a time is the way to go.. and yep it only shows what else needs doing.. I aways replace them if i've got it that far apart because it's not much more work to go the whole hog and rebuild it.

Two things are infinite: the universe and human stupidity; and I'm not sure about the the universe.

Plastigauge? assuming it looks allright when you whang the caps off.

Bugger off, I'm getting there.

(alex replying from nicky's account)
I got the engine from Wolfie, he says the small ends need doing. Apparently the engine has done only 29k.

It is the first turbo engine that im putting in a mini, and its on a budget!
hopefully we'll get this one in, and rebuild another out of the car for more power :) - we want 100-120bhp from this one.

what more info do you need?

what is wrong with the small ends ? The are interference fit so if there is something wrong it eventually leads to loose pin and scored cyliner walls.

apparently they need replacing - Wolfie?

i bought a 1 owner from new 29k 94 mini sprite with history from new, when i bought it it had a small knock consistant with a small end bearing sound, i had a 1293 motor so i dropped it in the car and sold it and gave the engine to alex thats all the history there is on it

Cheers for clearing that up, mate! :)
see the pics in my other thread for the results of pulling it apart :) i think the oil is gloopy because it's been mixed with water, as its been sat outside. - so that doesnt worry me, but the metal bits dont look too hot..

Like I said before there is an interference fit so there are no small end bearings to knock. Most likely the small ends are OK. Minis tend to run noisy, could be tappets, timing gear, big ends, whatever.

EEEEuuurrgghhh!!! That looks nasty!!!
FULL stripdown of the engine and box is needed there by the looks of it!

and the box?! :(

nah that'll be fine!

alex

AlexF

i dont get it.. you joking or being serious?
can i not just flush that crappy oil out with something? the box turns over by hand really nicely, doesnt feel dodgy or anything, but to be honest, i wouldnt know even if it did.. :(

Well I was being serious... I'd always pull the layshaft and mainshaft out if I had a gearbox off an engine anyway for inspection at the very least.
That mainshaft double roller bearing can be a weak point, and for ?17 i'd always swap it out. The layshaft and/or layshaft bearings are always worth inspecting and for the sake of ?20 for a shaft and the bearings, well worth changing if there are any doubts over its condition...

Remember, the weakness of the standard gearbox is well documented on stock 1275 engines, aswell as the standard (even with the modulated boost...) metro turbo.
For the sake of a full strip and inspect, it really doesn't take much time, but buys a real peace of mind. If i was still in the UK i'd say bring it up to me and we'll strip and build it together so you can see how easy it is. But as i'm not around, I'll say buy a haynes metro workshop manual of ebay for a quid, and follow the guide in there for stripping and building an A-series transmission. It's the best guide around by far, with lots of clear pictures, and it really is easy to follow.
I'm going to be re-building a transmission in a few months time, so I think a really good guide will be produced soon after!

Finally, if you have any doubts over the transmission strip/build, let me assure you it's idiot proof. it can't be assembled the wrong way. At all.

ps - I hope you'll be stripping down the diff aswell? the pins wear, the fibre thrust washers give up, etc. Again - just like the majority of the parts in the transmission, you may end up putting it back together exactly as it came out! (but i'd always replace the mainshaft double roller bearing)

Edited by turbodave16v on 7th Feb, 2005.

What special tools will i need? - the gearbox has only done 2000 miles, but i guess you know better than me about this stuff

28mm and 38mm sockets, circlip pliers.

I cant think of anything else other than a breaker bar...

cool :) i dont have a breaker bar, but they're only about ?15..

I think i'm going to wait a month or two, and spend some money on this, make a good job of it. No point doing it all twice!

Peterborough isnt too far away from me here in Coventry. I could pop round and go through it with you some time.

Altho I have never done a diff before....