Right i am going to be building a Zetec turbo engine from a very very low milage focus black top, the engine has no work at a and all of the shells are in excelent condition with no marks or scoring at all.

Can i reuse the shells as it seems silly to have to change them for the sake of it with it being in such good condition.

I know alot of people say change everything and it sounds a bit cheap but is it really worth it?

These show how little work the bottom end has done

 

yes you can reuse them BUT for what they cost as your changing/building everything else why not!

 

should have left them in... but now you have disturbed them you ma have to buy new ones... imo i would get the crank journals looked at and get some correct shells

if you marked up where every single one came from... then you may be lucky if you put them back in...

i did this once and it was fine however it could have been a very diferent story

 

thing is, is it worth the risk of another engine out strip down for the sake of less than Ł100 to replace some disposable components?

 

they are all back in situ, i have removed crank and put the caps back in with all of the shells in and the rods have got all of the shell back in with the caps on again and are stored in the correct order so i know exactly what came from where!

way i am seeing it is that they are genuine ford items that have not done any milage hardly so the engine wont need a great deal of work doing to it before it gets built up, and the millage that the engine has done compared to normal zetec millage is small and as they have got no wear marks or scores on them if its not needed then why change just for sake of it!

 

i have always put new shells in when the opportunity arose and consequently have a few sets of used yb shells which display expected wear patterns from a good engine.

recently measured them using accurate gear and can say that there is a greater variation in the crank pin diameters and ovality than measurable wear on the shells. in fact cosworths acceptable limits for main pin diameter vary by 0.5 thou from memory and non of the shells measure half thou of wear so without expert explanation on the benifits of why they should be replaced mine will be reused in future.

 

i gues alot of people want to avoid the expense as alot of people say its cheap to put new big ends and mains in but the reality is it aint if done porperly because crank needs regrinding-bottom end needs a rebalance in my opinion

 

It can be benificial to leave proven ones in, if they are unmarked, the tolerances are perfect and i would leave them.