[shop hermit]

I have a spare 451 engine (bought a complete engine and tranny, salvage, to get the tranny) the engine apparently had overheated and blew the gasket and-or warped the head. I plan to rebuild the engine in order to have a running spare. My question is.....does anybody know what effect a warped head has on the camshafts??? Resurfacing the head should not be a problem, if there was no other damage, but it seems to me that if the head is warped, the bearings for the camshafts would now be out of alignment. Is this misalignment going to be enough to cause a problem? Have seen several people post about refurbishing heads, but don't know if it was just for a valve job or if resurfacing a warped head was involved. If anyone has any information on this situation, I would really appreciate hearing about it.

 

[Smart Bob]

I would talk to an automotive machine shop & see what they have to say. If the head is warped, it will probably have to be straightened and then lightly resurface. Then the alignment of the camshaft bearings can be checked. Once the head is straightened, everything should be back in alignment. If you go this far, you may as well do a valve job and replace all the valves with a better quality aftermarket valve.

 

[SLIVERS]

As small and as easy it would be to ups a smart head I'm surprised that there's no one out there that specializes in rebuilding them or an exchange program.

 

[shop hermit]

I was assuming that "straightening" of the head would be accomplished be milling or resurfacing it, however as it is made of aluminum I suppose it could be straightened in a press. Maybe that is the usual procedure with a modern aluminum head, I don't know. If so, I suppose you are right, the bearings should be back in alignment. I agree with SILVERS, looks like some small enterprizing automotive machine shop should be able to set up a rebuild and exchange program that would be profitable. Yes, I agree ,SMART BOB, re-seating and new valves would be in order. You mentioned better quality after-market valves. I have seen offers of better quality guides, but not valves. Any information as to where they are available?

 

[DreamCarOwner]

When I rebuilt the head on my 2011 Smart a couple of years ago I bought new valves and guides from a parts vendor in the UK called Mollies Classics. Then I just took all the new parts to my local machine shop and they installed the new guides, valves, seals and setup all the shim buckets for proper valve clearance. Mollies is on Ebay, facebook and can be found at : https://smartatmollies.com . Not sure if they have all the extensive parts they used to carry.
Head warpage and camshaft bearing problems are complicated on a Smart head because the camshaft bearing surface IS the head surface itself. There is no typical line boring of the journals and using an undersize bearing. You should be able to detect cam warpage by looking at the wear pattern on the cam bearing surface and if in doubt, lay the cam in some V blocks and spin it while taking a reading on a dial indicator to surmise how much runout you have. DCO