After our eventful race last weekend I looked under the car which had bottomed out and realised we’d better check that engine!
Exposed flywheel with scuffs
The flywheel on these engines can hit the floor which can put a crack in the crankshaft around the rear main bearing. I’ve had two engines with crack here. One blew up in Anglesey and the other was condemned in an engine builder’s workshop as being close to the big bang.
We want this engine back in the other car by the end of the week so we tipped it on some tyres and got the crack out quickly. Armed with some Ambersil Leak and Flaw detector (http://uk.rs-online.com/web/p/leak-flaw-detector-sprays/4955027/) we sprayed the centre main bearing and the area of the crankshaft which is subject to cracking. I was keen on spraying the main bearing as the previous engine had a crack in it here. Since I first drove the car with this engine it had low oil pressure (35psi on the straights) so I suspected this engine had the same problem.
I hate being right sometimes… the centre main bearing shell gave it away (as did the oil pressure) before we even got the spray on. It was badly worn and yes there is a crack here. Luckily, well sort of, the crank is fine but is scuffed a bit.
NDT Spray showing crack in centre main bearing
That’s it for this block really. I need an engine in the car by the end of the week so I put it back together. The way the engine builder (believed to be Stevie Patton) sets the cam timing is to put an undersized dowel in the camshaft drive and use the bolts like a vernier. We tried to mark the position but I think we lost it so it’s also likely to be down on power now too! All round a bit of a rubbish day but it made it easy to decide on what to do next. Sell the 88 cheap and buy a brand new, crack free engine. I never liked that car anyway!