My engine is unfortunatley being removed from my car due to a potential piston problem, (exact fault yet to be known),
While its in pieces can anyone advise what bits are best to replace?? (engines only done 22k)
Thanks
Paul
Paul - who’s doing the work for you or are you doing it yourself?
Firstly no sh*t fights please, this is an honest posting based on a lot of VHPD rebuilds.
Guides, rings (or pistons as in your case), liners, polish crank, bearings (obviously) , reshim of cams and recut seats/lap valves. Retime cams with verniers. Inspect oil pump, replace if necessary, port pump backplate and block/ladder oilways, set liner heights, skim head minimally to ensure flat, hardness test head, replace collets. Replace cambelt and tensioner, consider having engine balanced properly at Vibration Free, check and replace water pump if necessary, replace rod bolts, replace flywheel bolts, replace all oil seals and gaskets as a matter of course. New head bolts. Consider sleeving front oilway in block to prevent oil seepage into coolant.
Consider bushing the rods when fitting new pistons to make them fully floating small ends. If you are retaining the existing pistons consider pressing them off the rods, bushing the rods and machining the pistons to accept cirlcips.
If you are looking for more power there aremmany more options to consider, but for a standard rebuild that list is about right.
Dave
dave - nice post, do you have a ballpark figure to do all the work suggested?
Depends if you factor in labour and whether the pistons need replacing, with existing pistons and no labour around �1100-1400 depending on exactly what you do, balancing, rod mods etc.
Dave
Paul - who’s doing the work for you or are you doing it yourself?
Hi Steve, unfortunatly I wouldnt know where to start on rebuilding an engine…
It is currently being taken out of the car at a lotus specialist in Honley and he is taking it for full stripdown and investigtation to a company based in Sheffield.
I’m hoping to know the full outcome tomorrow…
Hi Dave - thanks for the post,
the engine already has been fitted with piper verniers & emerald ecu.
It originally went in for the cams to be reshimmed so they will be redone when the engine is put back together.
Is there a rough price Vibration free charge for rebalancing an engine or is that dependant on how much material they need to remove.
I’m very confused at the moment after doing a lot a reading through historical posts on this forum + others to what way is best to go etc…
For one ‘if’ there is a problem with one of the pistons do I replace just one or do i replace the set ? If the set then do i go forged ???
Sorry if this post doesn’t make a great deal of sense
A full engine balance at VF is around �256, if the pistons are fubared then you have to replace them with forged pistons (the originals are forged).
Fitting them will require the rods to be bushed (as mentioned above) and you will need new liners. If only one of the pistons has a problem and the others are perfect then you could possibly just replace one if you had the pin machined out of the rod without disrupting the intererence fit. The replacement could then be fitted ‘interference’.
However it is unusual to have one rogered piston from a set unless you have had some sort of mechanical failure.
Dave
ok - the garage has phone me…
Thankfully the block and head are all fine I have been told that ALL the pistons are scored on the thrust face so will need replacing.
Just got to re-read through the above posts and work out what else to get done
I have some omega pistons here with an anti-scuff coating on the thrust face, thye might be worth considering.
Dave
I have some omega pistons here with an anti-scuff coating on the thrust face, thye might be worth considering.
Dave
How much are you wanting for them ?
Also, would you be able to do any of the porting/sleeving you mention ?
Hi Paul,
Sorry I didnt mean that as a sales pitch, I meant that you could now get them with an anti-scuff coating… I’m happy to supply them but you owe it to yourself to shop around first.
It might be better if you contacted me direct rather than discussing things here.
Dave
pm sent