cleaning pistons
Turbo Mini Forums

anyone got any do's and don'ts with regards to cleaning up my piston crowns as i've just pulled my engine out to split the box to have it rebuilt. trouble is i dont want to take em out of the bores as last time i tried to put pistons in i broke 2 rings, costly mistake!

i was thinking of using a soft brass brush in my drill but what about all the carbon, will it fook up me bores/rings if it goes down the sides?

its done about 3000 miles since it was built, had the head of after 500 miles to swap for my new one and there was only a small amount of build up which wiped off with a rag.





P.S. let me know if you spot anything dodgy as i havent had chance to have a proper look at it yet.

How about some of your mums Mr. Muscle from under the kitchen sink and a scotchbrite pad should work a treat if you spray it on and leave it for an hour or so.
And it won't harm a thing :)

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

cool, i'll get it cleaned up later on then, cheers dude.

I just use a rag with some thinners or petrol on to get the worst off, as with in a few miles it will be back all carboned up again!

Best 1/4 mile 13.2 seconds @116 mph
First 5 port miniturbo to make over 200 bhp on a carb?
First 5 port miniturbo to make over 200 bhp on Injection?

http://www.mattwoodsphotography.com

bud666 looking at the pics buddy it looks like to me that N0 4 is very oily!??

in the head and top of piston

it may be prudent to pull that piston for signes of ring damage, ring land damage etc

also on number 1 as well ?

yeah i think i may pull em out then, the bores are fine, no marks/scoring etc. ive been running it at 10psi so havent gone wild with it, plus it was RR'd before i booted it so hopefully it should all still be ok.

i would check the valve guides and seals first before you pull the pistons as it could just be oli drain from them sfter you have shut of the engine, if it was thats bad you would noticed it during normal running , if it was the rings.

just a thought as you proberly dont need excessive hassel and expense.

always looking for them bigger bunches of bannanas

well the head is only 6 months 2500 miles old. but come to think of it, i did get a puff of blue smoke everytime i started it when warm, didnt get any first thing though when it was cold to suggest stem seals.

You could get it converted to 11 stud

Metro turbo weekend driver,Mini turbo in the making again!

yep seams like a bit of oil drain down then, well that should save a bit of cash,

always looking for them bigger bunches of bannanas

well i'll do the stem seals anyway while its all apart, but would it be worn guides after so few miles?

AlexF

you tell me....lol

i have no idea but it would be just my luck for that to be on its way out though.

gonna take the head apart anyway and replace the stem seals just because ive got some knocking around and i may aswell while the heads off

well theirs more than one way to get oil in the exh on our engines!!

The turbo if leaking pours oil into the exh and burns... so if the heads new it could be an old turbo.

Don't take that to read you need a new turbo... they can smoke for ages!!!

Alex

AlexF

yeah its an unknown turbo, well it was on when i bought the turbo engine. i've got no intention of changing it until it goes pop or something drastic though or maybe when i win the lottery.

pour engine oil into bores aprox 10mm leave it for a wile ie 24-36hrs, if oil gone problem

Pete... won't the oil just run round the rings to the gap and then down to the next ring and out?!

alex

AlexF

I know i shouldn't but i'm LMAO at that one pete do you mind me asking how many engines you've build or deemed (problem) with your method of elimination ?

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

i have used petes method in the past - on rebuilt engines it takes a few days to all go through - if your engine is very worn or has knakered rings it will go through very quikly indeed

but you can just stick a feeler blade down the side instead...

or even measure the bore....

The oil method is not really going to tell you anything a compression test wouldn't have done with in the engine in one piece.

Alex

AlexF

well as it happens i did a comp test not long before we stripped it down. dunno if the gauage was playing silly buggers or what though as it went to 120psi, then to 150, then to about 160. it kept building up as it was cranking over. probably just me and davepugh not using the gauge properly though.

when we comp tested it at karls after it was run in, it was 118-120 across all 4.

Wasn't that with a STD head Budd ?
Did you do it wide open throttle like the last time ? and it was a different gauge so could read a little different.

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

you need the enigne to spin over untill the needle hits a maximum... about 5-6 times or 10-15 seconds..

As Karl say, remember to hole the throttle open!

Alex

AlexF

I regulally run redex through my spark plug holes and petrol, does that only keep em clean for a few miles too?

Previous Engine: 1040cc Morespeed engine, 1275 turbo head T2 Turbo Mirage Manifolds Megajolt
Previous engine: STD metro turbo, megajolt
Drives: 399bananahp (flywheel) Honda Civic Vtec b18c4 T28 Turbo 1968 Mini

Megajolt maps to download: http://www.jamesfawcett.co.uk/cms/index.ph...&gid=3&Itemid=3