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[aaronjb]

  You're more than welcome as well, Kevin.

Funnily enough I was out inspecting the crank this morning (you can just see it in the picture of the Nissan, sitting on the racking - it weighs a ton!).. the engine must have been built by a half blind hamfisted idiot.. and I suspect the 'real' reason the guy took it out of his car is that it blew up, not because it was too big (physically) to fit easily.

The crank is almost certainly going to need a regrind, sadly, thanks to things like this:


(You can clearly see where a foreign object came out of the oilway and got trapped between the crank & bearing)


(Looks like someone attacked the crank .. or whacked it putting the rods & pistons in, more likely)


(I'm guessing it spun a bearing - that looks like the outline of the oiling groove in a full-groove bearing, to me)

[aaronjb]

Yikes! The pictures are a tad large..  I ought to resize those..

[Kevin Wood]

Mmm. Yep, that doesn't look too healthy.

Either been built by a Neanderthal or it's been spinning in a soup of bits of rod, IMHO. Still, it'll come good after a grind, I'm sure.

[aaronjb]

Fortunately you can get bearings for up to +0.050 undersize cranks.. which reminds me I meant to get the vernier callipers out and see if it's already been reground. Would be good if I could remember where I put the verniers..

[feeutfo]

Thanks aaron, sorry to see tue damage. 

Hope it gets sorted. 

[aaronjb]

Cheers Chris - I'm sure it will.. either a regrind or swap to a steel crank from Scat or Eagle (~£400).. the more I survey the more I find bits missing that I'll have to replace, anyway.. like the fact that the seller only gave me 13 lifters instead of 16

[Kevin Wood]

Cheers Chris - I'm sure it will.. either a regrind or swap to a steel crank from Scat or Eagle (~£400).. the more I survey the more I find bits missing that I'll have to replace, anyway.. like the fact that the seller only gave me 13 lifters instead of 16

That's the spirit! Enforced upgrades.

[aaronjb]

  I can see me ending up with just the block & heads in use from this engine and everything else new.. still, even if that's the case, it should build into a stonking engine

I already know I need new lifters, at which point I could swap to a roller cam & lifters.. that would necessitate new valve springs too, of course.. and I already need to rebuild the rocker arms as they're incorrectly shimmed and missing bits (hopefully PRW will sell spares for their kit)..

It's all downhill from here, isn't it 

[Marks DTM Calib]

I have seen worse cranks than that reused to be honest.

[aaronjb]

I posted pictures of the crank up on the Cobra forum where one of the few people with serious knowledge of the FE engines happens to post occasionally (Mike Huddart of Huddart Engines up in Crewe); his opinion (like yours) is that those marks are nothing to worry about, but..

The work that's been done to 'balance' the crank is worrying - the 428 crank is externally balanced and this one appears to have had an attempt at being internally balanced.. there's been a lot of weld added to the front & rear of the crank and then ground back, as well as having one of the rod journal areas (not the journal itself, obviously) lightened.. to him that looks very odd indeed. In fact, here's what he said:

The last pic and the balancing photos are the most worrying, look at the front counterweight, that looks like welding that has been ground down, as though a balancing hole has been filled in and welded. Not withstanding the implications of weld that has been ground off and the likelyhood of said plug dissapearing through the crankcase you have to wonder why somebody has had to ADD weight to the counterweight in the first place, I presume you havn't got Carrillo (heavier ) rods or somesutch.
Couple that with photo 5 from the first set where you can see grinding ( lightening ) arround the rod journal, the complete opposite to the front counterweight and you start wondering what the heck is going on.
You CANNOT neutral balance a 428 crank by simple drilling or grinding, you have to add a considerable amount of heavy metal to the rear counterweight, if this is not obviously present then all you have told about balance is nonsense.
Forget about dinges and rust, potentially the most destructive problem you have is balance............. or lack of it !

And the accompanying pictures:


(flywheel end)


(nose end)


(journal work opposite the flywheel balance end)

[justjohn]

You would think it had been thrown out a top floor window