Welding up a crankshaft journal?

[chevy2]

Got a call yesterday from a mate as to whether i could weld up a big end or main journal on a quite old Cadillac engine,
Not seen it yet but apparently its had some minor damage around a journal area,
it needs building up with some weld so that it can be machined back to original size,

couple of things to add, it cant be machined down any more as i think its about as small as bearings are a available and its not for a race motor so wont be getting any abuse,

the question is although i think its cetainly do-able what would be the best filler rod to use?????
i was initially thinking a standard A15 rod?.

 

[711jrp]

The normal way to approach this is to have it chromed.....

 

[Stueeee]

Is the damage too bad to consider metal spraying? any weld distortion could be a problem if there isn't enough metal on the other crank journals to "grind it straight"

 

[bill_gj]

Might be an idea to try Googling for US sites with information about 'stroking'. Sorry if you already know about all this, but building up cranks so that they could be re-machined to a longer stroke was common in the 50s and 60s I think. All done by welding and regrinding.
Distortion has t be a problem, though.

 

[Robotstar5]

I would get it sprayed and reground

 

[Bill Edwards]

I'd be looking to get it sprayed instead, the distortion could be a serious issue leaving you with a bent crankshaft!

 

[chevy2]

Thanks guys, i know about the stroking thing as a mate has a crank thats been offset ground and uses a conrod with a smaller bearing creating a larger stroke,

forgot all about the metal spraying thing,
i sold a used cut-out chevy engine quite a while back and the guy mentioned he needed the crank metal spraying and then regrinding,

think i'll call him and recommend metal spraying as its certainly the best option

 

[dannyp]

defanatly the right way forward,

cranckshafts dont allways weld, depending how it was made it may form a weackness in the cranck itself. if he has it sprayed it'll lso be abel to go straight in the grinding machene as it won't trash the wheels same way lumps of weld would

 

[normspanners]

I did a lister once that had a well worn journal I searched the books ( no internet then ) and found a set of shells that measured up or should i say down, to the journal size when cleaned i thing they where perkins marine that went to -60lister only went to-20 ground the one journal remachined the rod down to the correct id and bingo still running now 28yrs later

 

[chevy2]

A mate of mine once bought an 80s Cadillac real cheap that had a misfire,

Long story short, the crank was badly damaged on one bigend journal and someone had removed one rod and piston,
then fitted a jubillee clip to hold both the bearings in place so it held oil pressure and still ran

 

[normspanners]

that was a usual fix for essex v6 in tranny rally barges back in the day, I came all the way back from bulgaria through yugoslavia ( bosnia now) and over the alps towing a works chevette with a v5 tranny + also helping a brit in a renault 4 that had blown ahead gasket and ended up with him tied to the trailer for about 50 mls!!
That old van had stickers on the front wing like the old air aces had swastikas for blown up stukas, we had black pistons and rods-----

 

[cr500dom]

A place I used to work (Engine reconditioners) had a crank welding set up for reclaiming journals before re grinding, that were too worn for Metal spraying.
It was like an automated mig welder, but with an additional powder flux feed down to the torch as well.
It would rotate the crank and manipulate the torch to just reface the journal.
It made a colossal noise though, lots of smoke and there was quite a bit of clean up needed afterwards.
We never had one back that had been through the process and reground either, and that included some Stroked Essex V6`s that the owner and his son raced in capris with some success (Re welded journals and then offset ground)
Sadly they are no longer going, but I know the Kit and the process exists to do what you need Chevy2

 

[Rig Pig]

That sounds like the old engine shop (I forget the name)in Rashs Green Dereham?

 

[cr500dom]

That sounds like the old engine shop (I forget the name)in Rashs Green Dereham?

It was indeed !!!
AES in Rashes green
Wonder what happened to all the kit ?

 

[Rig Pig]

All auctioned off when they shut, a real shame they went they were real tradesmen and nice blokes too, I was project engineer at a little plastics company round the corner, if I needed anything making they would let me use there machines.

 

[cr500dom]

Dave (The owner) was a cracking bloke, and like you say the other guys were great too

 

[normspanners]

I have had several things hyd cyl rods worn gear shafts etc chromed back up above standard size then reground back to std, in fact I had one that I could not get imperial seals for and chromed it up massively, them machined it to suit a new metric seal, machined out the old worn end bush to the metric size ---- perfect.

 

[chinnybeer]

I have done it before on mains and other rotating parts that were worn using mig. We used straighten the crank (if required) after welding, machine the bulk off on the lathe then grind the journal. Never had any issues.

I would imagine cr500dom and Rig Pig will know the place I used to work many years ago, Knights & Son in Norwich.

 

[dannyp]

how did you about straightening a cranck ?

 

[jinjahbiscuit]

Hydraulic press, vee blocks, dial guage and a shed load of patience.