how to adjust thrust

[herbiehind]

pre-build going well , all mains perfect. rods in spec . but thrust on crank is .0005" . or half a thousandth . what to do guys? this is one tight motor . while i got ya, i'm at .038 on deck clearance . is it worth it to go ahead and zero this thing ? i imagine i'll have to get push rods plus the machine work. but is it worth it? will i get a good h.p. boost? or good mileage or 87 octane ? what say you strokers?

[IH 392]

Take a BMFH and a wood block and WHACK the crank from both ends three or four times and then measure your thrust, on the quench I'd deck the block, I wouldn't exceed .050", I'd have them take at least .030" off and maybe even .035"

[herbiehind]

thanks IH 392 . seems easy enough . yeah, guess i'll get it decked . dont want that regret. thanks again .

[SilverXJ]

There is a bit more than that. You don't want the caps tightened all the way.

[dwg86]

pre-build going well , all mains perfect. rods in spec . but thrust on crank is .0005" . or half a thousandth . what to do guys? this is one tight motor . while i got ya, i'm at .038 on deck clearance . is it worth it to go ahead and zero this thing ? i imagine i'll have to get push rods plus the machine work. but is it worth it? will i get a good h.p. boost? or good mileage or 87 octane ? what say you strokers?

Do you have the thrust bearing on the correct journal? Some on have tried to install it on the rear bearing cap. It goes on #3.

[herbiehind]

pre-build going well , all mains perfect. rods in spec . but thrust on crank is .0005" . or half a thousandth . what to do guys? this is one tight motor . while i got ya, i'm at .038 on deck clearance . is it worth it to go ahead and zero this thing ? i imagine i'll have to get push rods plus the machine work. but is it worth it? will i get a good h.p. boost? or good mileage or 87 octane ? what say you strokers?

Do you have the thrust bearing on the correct journal? Some on have tried to install it on the rear bearing cap. It goes on #3.

yeah lol it's on #3 .

[herbiehind]

There is a bit more than that. You don't want the caps tightened all the way.

silver; can you elaborate? i need to do this right. thanks

[SilverXJ]

http://www.enginebuildermag.com/Article ... ilure.aspx About halfway down is a good description.

[gonridnu]

Your last "whack" needs to be from rear to front before tightening the cap. The thrust bearing primarily sees loads towards the front of the engine from pump pressure on an auto and clutch pressure from a standard. It is perfectly acceptable to lightly sand the thrust bearing on a flat surface to gain thrust clearance.