Case repair fitness evaluation

Bottom End (crankcases and crankshaft)
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Excalibur
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Case repair fitness evaluation

#1

Post by Excalibur »

As luck would have it, I found a piece of circlip missing from a piston on my '61 Pan. It's one of those spiral lock type with about 180° of clip broken off, gone. I decided it would be better to do a strip down and check rather than risk it.

Brief summary of condition:
The big end is feeling really good.
Light corrosion here and there on various parts.
Cam looks good, hardening fine.
Timing gears have some marks, should tidy up OK..
Oil pump return gears show few impressions to teeth.
Breather tunnel has a couple minor scores, nothing serious.
Crankcase has a weld repair behind the tappet blocks...
DSCF4778_zpsnbfsd4kq.jpg
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Oil feed hole is not nicely finish after weld repair

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Tappet block bolt blow out repair..

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I'm considering how to test the case for leakage potential. I'm suspicious because there was a leak somewhere in the area.
The repair looks somewhat porous. The front tappet block has a bolt blow out and weld repair. The tappet block screws next to barrels are taper seat type that appear original. The ones adjacent the timing cover are all cap screws.
The rear tappet block has been the target of weld up including oil feed gallery which is now dangerously close to the tappet block edge.
Puzzling, is the weld along the outer part of the crankcase mouth. This goes across oil galleries.
Should I pressure test at perhaps 20 PSI and apply soap bubbles??

I've read a number of K-base threads with some good ideas there, especially the tappet block thread plug repair of a clumsy earlier repair, drill and retap.

Any thoughts or tips please? Thanks.
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58flh
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Re: Case repair fitness evaluation

#2

Post by 58flh »

EX----Im sure you will get alot of feedback!.I can tell you /Im not a good welder of pourous Alum.But I have seen Great Tiggers apply thier craft & just by looking at the finishes/--It seems like the case was not PRE-Heated & kept at a steady warm temp to end-up like that.I would send them out & have them looked over by someone who knows about these motors.When mating it to the other case & putting a few bolts-thru just snug.How is the fit of CASE to CASE!--Use a feeler guage if you have them thin enuff & see what kind of gap your dealing with.However this is the least of your problem,you can always lap the mating surfaces if not badly warped!.Its the bolts that will have steady tourque on them that concerns me.That & the not finishing of the job/unless it was deemed finish are horrible.Def. let a PRO look at it is my best advice to you.-----Respectfully----Richie
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