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burgundyben

Jedi Hopeful
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My biggest worry was pulling the engine apart and not being and to find what caused one of the big ends to disintergrate.

I got the engine and box out, (had to get a chain block and use a tractor as my engine hoise would not reach far enough).

Head seems in good order, water pump is knackered(knew that anyway), camshaft is good, rocker gear good, tappets good, pistons and bores good, timing chain new, number one big end shot, looks like the shell has been spinning, other shells not too clever. Think the conrod might be knackered.

The cause? Centre main bearing cap nuts were about 2 turns short of being done up!! Whoever it was that did the rebuild was a sloppy worker.

Need to very carefully inspect the studs and nuts and the cap itself, will ask the machine shop to very carefully check the crank for straightness and cracks and check the rods for straightness too.

There were some funny marks on the pistons at front of number one and rear of number 4 above the top ring, I guess this was caused by the crank flexing in the middle cos it was not bolted in place.

Well chuffed!! /ubbthreads/images/graemlins/thirsty.gif
 
it did cross my mind that the missing step might be the torque wrench.

The nuts are nyloc rather than have tab washers, not sure what's most common on these engines.

Certainly the front and rear bearing the nuts were well tight.
 
[ QUOTE ]
it did cross my mind that the missing step might be the torque wrench.

The nuts are nyloc rather than have tab washers, not sure what's most common on these engines

[/ QUOTE ]

PITA Lock tabs are the original fitment. Steel lock nuts should have been used not Nylocks. I would replace them all with new--Fwiw---Keoke- /ubbthreads/images/graemlins/hammer.gif
 
Yes, check the crank for defects. My Bugeye was plagued with three cracks and a .012 bend. Chewed up the rear oil sealing rings and leaked like the Exxon Valdez. Engine was out four times in an attempt to fix the problem. I got a good deal on the car and figured it out (after I had pulled the engine three of those times). I would suspect that with a loose center main cap you very likely have a bend. Sometimes a bend can be fixed. But be sure to get a magnaflux inspection done. A broken crank later on can "knacker" (as you say) the whole engine. I knackered (I love that word) a Triumph motor I built on account of neglecting to magnaflux the crank. Things get interesting when a crankshaft breaks. Usually because it happens at speed under high acceleration load. And in traffic on a freeway onramp. Kablewie! (I like that word too.)
 
The Knackers Yard was the end of the road for working horses when no longer fit for service. So if a horse was knackered it had been turned into glue and dog food. Modern useage seems to take two turns a/ Tired or b/ Totally beyond use (ie the original meaning)
 
Knackers.

Knackered is such a common word here in the UK it never crossed my mind, its also slang for some body parts ie 'I've been kicked in the knackers', cockney slang is 'Jacobs' as in 'Jacobs Cream Crackers' = knackers = nuts!

Jacobs crackers being a well know brand of savoury biscuit!

Got a bit off thread there....

Have been to the engineering shop, seems that big ends were -020 but with -010 shells fitted...

Chap thinks that the number one might not clear at -060 so I may need to buy a new crankshaft (ÂŁouch). He'll check for straightness and cracks before the regrind.

He thinks they can rescue the conrod, machine a bit of the mating face of the cap and then re-bore a new hole, he says the rod will end up marginally shorter but on this type of old iron for normal road use it will make no significant impact, he's been doing it 40 years and made a spendid job of my jaguar engine so I trust him well.

Making progress.
 
Re: Knackers.

You do know that oversize main and journals can be welded and then reground to factory specs if all else is ok.

Is another option from a new crank. Supose they might do just one bearing in your case.
 
Re: Knackers.

Indeed I mentioned that to the chap, he was not keen to do it, I guess if the big end does not cleaer at -060 we'll revisit that idea.

Thanks

Ben
 
Re: Knackers.

It is amazing what "old iron" can put with and still run. My 49 Plymouth flathead ran with a hole in one piston (though the compression was a low 25 psi), cracks in three piston skirts, broken rings on two pistons, and disintegrated bronze wrist pin bushings.

So a little off here or there in the end is likely not a big problem. Just don't race it around!
 
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