14 replies to this topic

[cristiano1968]

Hi
Any idea how my engine bores
Liners look.
Do you think a honing is fine or a bore?
Thanks

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[absx2]

If there is any form of a step at the top of the bore it`s time for a rebore and new pistons.

Late A+ 998 motors are bullet proof so i`m wondering why it is in bits, was there an issue as they will generally go on forever and smoking issues are usually down to the valve guides and not the rings.

Even with a large step at the top of the bores they will not give any trouble as long as they are not pulled apart.

[cristiano1968]

Hi I took it apart because I had my engine out to respray the body.
So I decided to do a rebuild.
It was leaking and burning a lot of oil.
It's a 998cc a plus
So I'm going to put a new cam in
And a stage 3 head.
The pistons are worn
The crankshaft measures within limits.
So I'm thinking just to get it honed and fit new pistons.bearings
Camshaft bearings etc

[absx2]

OK, rebore + 0.020" new pistons, check crank for oval.

It`s in bits now so a full rebuild it is.

[cristiano1968]

Yes was thinking that as well to do a rebore +0.020"
Got to find a good machine shop here in Italy?
That's good with minis
Saving up to order some new pistons
Maybe from somerford mini uk

[timmy850]

But is it standard bore now, or has it been rebuilt in the past? Same goes for the crankshaft bearing size

Measure everything first, check with the machine shop what size they will clean up at, then order the parts

[cristiano1968]

It's standard
Had the car fo 30 years never had engine out.
Never been rebuilt .only changed the clutch 3 years ago and through the years new radiator starter motor.i did a carb rebuild.
I talked to a recommended machine shop
He told me over phone a rebore and new pistons
But he needs the new largerb pistons to
Do the rebore

[cristiano1968]

Keith calver seems to have some good pistons on his web site

[luismx123]

minispares has them too. I just did my 998 and rebored to +.20 with an AC dodd RS cam and so on.

[Cooperman]

Mini Spares P22463-20 is the piston which should work well for you. The gudgeon pin is  press-fit-type (check that you have the rods for this)..

After re-boring, do a trial build and measure how much needs to be skimmed from the block deck in order to bring the piston tops up to within 0.005" of block deck level at TDC.

[cristiano1968]

Hello cooper man.
Yes mine are press fit.
I will take a look at the mini spares ones?

[cristiano1968]

Out of curiosity
They have an arrow on them.
Is it right to assume they have to be fitted to conrods with arrow pointing to the water pump side of engine?

[cristiano1968]

Just looked they go towards the front of engine forward from inside car

[timmy850]

They normally point to the water pump end? The conrods come in 2 pairs, so they have to go in the right cylinder or it won’t work.

Have you measured the diameter of the bore or pistons?

[cristiano1968]

Getting 0.020+ pistons and a rebore
Going to take it to a machine shop here in italy .
So getting enough info as possible to give the machine shop