Datsun Roadster Forum-311s.org

I had spent so much time building a clone 67 2000, that when I bought a real one I wanted to rebuild the motor to the best I could. I sent a non-smog head to Rebello and spent a fortune to get that set up, ordered all new gears and heavy duty chains from JT (they are incredible), new Solex pan baffle and carb shield (also from JT), hell the complete Solex air filter is one of his. I got oversized pistons from Stan and had them coated, full gaskets and studs from Dean, rebuilt harmonic balancer from Dean, a JT aluminum flywheel, and on and on…today the Machine shop called (I needed my block tanked, bored, and my crank and rods balanced) and told me that block 589 is cracked and can’t be saved (machinist says it can’t be welded in the location that the crack exist). Tom from Engine Supply Machine Shop said he noticed the caps seemed sloppy in the middle so he magnifluxed around the saddle supports on two and three and there is a crack on number two running from the base of the bore down to the oil pan base. I’m completely bummed right now as I’ve spent so much to finally have a numbers matching 67 and now that is dashed. If you’ve ever seen my restoration site, I already have a complete U20 that is very nice, but it’s nowhere near a correct number and I painted it red since it was a clone car (and wouldn’t disassemble that just to use more new parts). I have 5 other U20 long blocks but the lowest number I found was 10782…The hard part is the block has been gone for so long and I asked if everything looked good when I dropped it off so I wouldn’t waste money…really just venting to friends as my wife doesn’t understand why I’m so livid right now. I know there is so much debate on the correct block number vs. not correct, but I was so close…signing off to lick my wounds…

Ah life... so go the best laid plans of mice and men...
I have heard of some unstamped blocks... would this be a possibility?

I have one. I didn't know what I was buying when I got my 2000. So, I didn't know where the engine number was. Now, I do and it is blank.

Blank engine number would be the way to go.
My understanding is if your original engine is un-repairable and you bought a replacement engine, it would have no number,so being a factory replacement part, the car is still considered original. Bag up the bad motor, copy the machine shop receipt saying it's cracked, and put it in the shed.

Why is it that we can replace everything inside and out side of the engine and still call it original, but if we replace the block, all of a sudden it's not! For some reason an unstamped block seems more accepted than a block from another car, but in reality neither is original. If it were me and I had another stamped block I would use it unless the cost of buying an unstamped block was of no concern. Either way it's no longer considered an original motor. What I absolutely would not do is stamp or restamp a different block and pass it off as original, that would be fraud! Mike

Are you sure the block can't be repaired? I would be thorough in investigating that with top machinists.
Good luck. Sorry about the roadblock with the block.

Linda

Linda wrote:Are you sure the block can't be repaired? I would be thorough in investigating that with top machinists.
Good luck. Sorry about the roadblock with the block.

Linda

+1

It might cost a small fortune, but I bet there is someone out there.

Can't remember which episode of Jays garage but one of his old blocks was stitched together by some Co. The video was about his current restorations. Notcheap I'm sure but if it's that important to have a specific number it can be done.

Boy, nowadays there isn't much that can't be repaired....block sleeving, nickle welding rod, etc.
If you're convinced, so be it but I wouldn't give up easily.
http://www.locknstitch.com/engines-cast ... ustry.html
http://www.enginebuildermag.com/2015/04 ... ad-repair/
http://www.aa1car.com/library/ar497c.htm

Dan

Yea, all those methods have been around quite a while. The plug repairs are not great and take a very long time except for small cracks.

Welding/brazing is a major challenge since the iron often recracks when cooling even with preheating.

Depends a lot on where the crack is. And since its a used block, oil/antifreeze will seep from the pores of the casting to contaminate the repair. (Been here...done that)

Buddy, if you can get the block to me, i know a guy who may be able to repair it--but even if a repair can be done properly, there is about a 50/50 shot at re-fracture under stress and temp cycles. - kinda sucks from that perspective. - that is why almost every machinist/builder will tell you to find another block and not put more money into the broken one..

Sorry about the mis-fortune . J

The Datsun gods are a fickly bunch. Sorry about your bad luck.
PS. Your website is amazing! I love it! It has really helped me get my car back on the road.