Bottom end advice wanted

[Chri5]

Following on from my knocking engine thread.....
I've now removed the head and found no damage to either valves, piston crowns, cams etc etc, but it would seem the bottom end is shot

Cyl 3 which showed a low compression (120psi) is a bit oily (although I did put a little oil down only this cylinder when doing the test) but its also oily on the valve area too.
Also, more worringly, that after a couple of revolutions of the crank, number 2 piston seems to be slightly behind number 3 when approaching TDC. Once its @ TDC I can actually push it down 1-2mm :dapprove::S Small end failure??

I have included a video of the piston being pushed down and one of it approaching TDC

http://smg.photobucket.com/albums/v625/Chris_Turbo/?action=view&current=100_1284.flv

 

[fuel_slut]

What is the condtion of the bores? can you see any blemishes on the bores?

 

[Chri5]

Not inspected them thoroughly but there was nothing obvious, could see faint and even honing marks on all 4, thats all.

 

[Mark One]

You've clearly got serious issues on clyinder 3, so you have 2 options:

A) Remove the sump, remove the cyl 3 bearing cap, check everything and replace parts as necessary.

B) Buy a new engine.

Given that it seems to be only 1 cylinder, I'd probably end up going with A. But it could be expensive. If the bottom end has gone due to oil starvation in the big ends, it'll be a mess and not worth saving.

 

[S&K]

Take the crank out and inspect, if it isn't too scored get it re-ground and fit new oversized bearings, re lap the valves in and re ring the pistons if the bores are OK. If it is a little end then replace that or get a good 2nd hand rod, should be fine after that.

 

[sideways danny]

that's pretty buggered. I'd suspect the big end bearing is heavily damaged, and it's going to have taken the crank with it

 

[MikeB]

Probally easier/cheaper to replace the engine

 

[Tom84]

looking at your head photos, looks like the inlet valves have been clipped by the piston so i would check them too

 

[Chri5]

Thanks for all the suggestions guys!
That was my thinking too regarding if 1 is heavily damaged, chances are the rest wont be far behind so they'd all need doing, and thats assuming the crank isnt goosed

Maybe another engine would be the best idea given the time and cost it would take to sort this one out.