6 replies to this topic

[mbican]

The current engine in my Spec Miata needs a rebuild, excessive blow by has now turned to badly smoking, fouling plug #1. Current engine in car is a big nose, have a spare engine that came with car that is a short nose, probably the original. Is it worth rebuilding the short nose? Put a big nose crankshaft in ?  Scrap the short nose and just rebuild engine in car?  Would be nice to have a spare engine though,  Thanks

[chris haldeman]

Done properly the short nose is fine

[mbican]

Loctite on bolt threads? Blue? Red?

[B(Kuch)Kucera45]

I rebuilt my short nose in 2008 and I'm rebuilding it again right now. My motor (short nose) had over 23,000 race miles on it with less than 4% leak down on it. The only reason I'm rebuilding it now is because I was low on oil pressure (worn bearings) but that would be expected with that many race miles on it.

I say go for it and rebuild it !

[dc2696]

Red lotite. And don't put the key in upside down and you'll be fine.

[davew]

Inspect the key slots in both crank and pulley. Any damage throw away. New key from mazda. Remember the key can go in 8 ways. 7 ways are wrong, only one is right.

 

Red loctite requires heat to remove. Blue can be done without.

 

New hardware, I have better than factory bolts made by ARP

 

dave

[mbican]

Crank slot looks good, plan on new key and bolt. Thanks every one, gonna start tearing it down this weekend.