MB stripdown and rebuild

[Alan Geraghty]

[quote=Phil Payne]Mahle themselves have been out of the loop for over a decade. I wrote this in 2003 or so - I'd like to know what the curren status is:]

Phil,
2 different engine re manufacturers here in Ireland gave me prices (!) for .5mm oversize Mahle pistons ex Germany, possibly old stock but available nonetheless.
.25mm O/S were not available.

Alan.

[Alan Geraghty]

Not much progress lately but I did get the block and crank back from the machine shop this week.
The block has been bored out and the deck skimmed.




The crank has been reground and under size bearings supplied to match.



Oversize thrust bearings are not available, oddly, so the guys did not touch the thrust surfaces, so I can use standard size bearings and hopefully maintain the end float limits.

I have sent one of the pistons to the piston maker in the US, so I will be about 6 weeks before I see anything in the post from them.

The con rods will have to be re bushed to remove the play that is currently on the pins (not an issue as there is a bronze bushing in there anyway).

In the mean time I have to decide on a KV head or another MB head.
My head is repairable, but at a cost, and I would rather spend the money elsewhere, as lots more will be need berore this tiger growls again...

[Phil Payne]

Originally Posted by Alan Geraghty

2 different engine re manufacturers here in Ireland gave me prices (!) for .5mm oversize Mahle pistons ex Germany, possibly old stock but available nonetheless.
.25mm O/S were not available.

The first oversizes were the first to go in the spares consolidation exercise. It's a lowest common denominator issue - everyone who needs the first oversize can actually use the second, but then of course there's no more room for messing about.

Certainly RMES (and I would expect any responsible outfit) won't bore out a cylinder without the target piston in their hot little hands.

I've not heard of problems with pistons, but I do remember one case of a scored crank where the owner bought 1st undersize shells and was then told the crank had to go down to 2nd undersize. Fortunately the shells he'd bought weren't expensive and were rapidly used by someone else.

[Alan Geraghty]

Originally Posted by Phil Payne

Certainly RMES (and I would expect any responsible outfit) won't bore out a cylinder without the target piston in their hot little hands.

A fair point Phil, but I got the block machined, then measured it and give the dims to the piston maker, that way they have to take responsibility for sizing to my block, not the other way round