I got given some camshafts and crankshafts years ago... D*lly is sick so i thought i would build a new engine for her from bits i have and only buy what i really need to save costs.

what can i check? How do i know if they are any good?



should this bearing have the odd slot hole in it?



has this gone beyond clean up?



one must be ok? I hope!



how much wear is acceptable and how can i check?



does this lobe corrosion damage = scrap?



can the bearings be removed and re-fitted? (if its damaged) if so how?





many thanks

Tim

Crank shaft
Check the lateral play using feeler gauges, see photo. Max is 0.14 mm. Clean, oil and feel both ‘’bearings’’ if they turn without biting.
Also check both bearings for horizontal and vertical play.
Grab the con rods and feel for vertical play (big ends), preferable no play. Small amount of side play is acceptable but not to much.
Same for small ends (bronze bush for gudgeon pins) needs to be tight fit. If not you hear the famous knocking from the engine.
The front bearing I’m concerned about. It may be a matter of time before the bearing likes to move sideways. Someone didn’t place the bearing the correct place when the engine was put together at some stage. Others may not worry about it but I would.

Cam shaft
Check the teeth on the gear for wear marks (crank shaft too). Clean, oil and feel the bearings, no biting or sideway movement. If cam lobs are pitted or badly worn, it’s a reject.
Have a look where the oil pump is located to see the wear marks.

main crank bearings are not replaceable AFAIA. The photo of the one with pitted lobes might make a nice paper weight
Would you really be happy spending all that time and effort rebuilding an engine with ' doubtfull parts ' for it to possibly fail en route to a big meeting.

Good luck

Going to ask the racers on the weekend about getting a standard cam re-profiled. I dont want a rumpy race camshaft just the ones I have repaired to as good as new finish.

I think to be honest the crankshafts are dead. I spoke to that someone and he remembers fitting them wrong hence the damage to the crankshaft bearing... If i cant change them I am going to be looking for a replacement crankshaft (2nd hand!)

cheers for the pics and input.

Tim

I have 2 crank shafts with the big ends gone now (both damaged due to lack of oil!) are they repairable at all or are they now scrap metal?

Where's the best place to go and what sort of cost is involed if they can be repaired?

or

Where can i find/buy new cranks from?

Thanks

harry,
if the big ends are gone, that's probably game over, unless that fellow who advertises on Ebay about his 2CV crankshaft balancing service can do a 'mix and match' with the remains.

He's certainly done work for the 2CV racers, separating cranks and pressing them back together, only thing I'm not too sure about is the possible reduction in interference fit which can occur during that process.

If Tim hasn't binned that crankshaft of which he posted some pictures, maybe grab that?
Didn't 'spanners' have one with a similar fault, which went into the race engine he built, following my advice...

ken

Indeed I did.

I built the engine which ran as sweet as a nut if perhaps a bit smoky.

That said though, it's not been used in anger yet...................

Tim
heed the advice that crank will be fine as long as the dowel damage is the only thing wrong, if the big ends go then its scrap time

as for the cam, Paul Robertson was the one to contact in the race club to have a bank of spares for the race re profile

however giving the cam to Kent just speeds up the process by which they end up in the scrap bin its a lottery one of mine ( which was fished out a dumpster at 2nd Snet) has done numerous 24hrs in Coghills, Harper and Hollis cars, however some dont even last beyond the run in period

the general rule for cam wear is that if you see a change in the surface and the colour its pretty much on its last legs, the death knell is when the wear area at the peak of the lobe looks pitted which is usually the end of the hardening and wear goes down hill rapidly

dont send your cam to Kent they will just waste it better of going to PP (see the oil cooler thread- but i think he does new grind from new blanks), STP or even "Piper" in the uk if they are still going

altho re profiling and case hardening wont be cheap. and id not even bother going down the race club route as its dire

@ Spanners-not going to be the crank thats causing the smoke though is it

Sean

Absolutely mot, it was merely an irrelevant "aside". Not terribly sure why I even mentioned it to be honest but I did and I can't be arsed to edit it now!

Actually, as a further aside, I say it was a bit smoky-it smoked no more really than the engine we ran throughout the entire 24 hour weekend and I think that probably used about a litre of oil throughout including testing and qualifying etc!

Just thought I'd join in the random posting on threads.