Technical 1242 Bottom end rebuild

[DRSIK]

Hi Folks

I just got a 1242 bottom end from Fleabay and I am intending to recondition (so it is better than new ) it over the winter and swap it with the 1.1 bottom end in the mischief machine in the spring.

Can you advise me of the bits I need and any possible pitfalls I may encounter

 

[Ziggy122]

you most likely will want the exhaust completly out the way (manifold wise)
So get treating it now with oil if i were you

You need to ensure there isn't overside bearing caps already in there

Really you need to measure with a plasti-guage

But i've seen alot of people just slot new big ends on and torque them up
Without having the crank reground - ensure you lubricate the crank and shells BEFORE fitting, as thats the only lubrication it will get, untill the engines running and oil pressure comes up

Tbh, my last punto did 100K and didnt have any big end issues
and its not common tbh....

I wouldnt worry

Ziggy

 

[DRSIK]

Thanks Ziggy

The block is already separate from the car - the car is presently running on a 1.1 block - I am swapping for a 1.2 (more low end grunt) after I have "fetteled" it.

I was thinking of putting in new rings and honing the bores so that I , in effect, have a brand new engine.

(I already have a new head - decent gearbox - new stainless exhaust - new 40mm throttle body)

Do you think it is worth it ?

Also any ideas as to anything that would improve the bottom end further (crank grinding/ head gasket types / block skimming-if possible) - this is a no rush project - I want to do it right THEN fit it.

 

[Ziggy122]

ive never heard of a punto needing a bottom end rebuild tbh

But then again there cheap to just drop a new engine in

If time is no object, i'd whip sump off - clean the sump and strainer out
Check the bottom end for play

But you cant really check the crank without a plasti-guage kit
(bits of plastic you fit - the squish of the plastic indicates the gap availible)
Less crush = bigger gap
A large cruch = tight tollerance)

Ziggy