Oil Pump Drive Clearance?

[PRO_32]

Just after the standard pump gear to crank drive clearance if anyone knows. Just checking mine as I'm getting ready to assemble soon and seems excessive to me.

Cheer's

[Shoota_77]

I was going to fit a locally sourced crank collar for my 30 build and it was something crazy like 9 thou clearance to the pump ring from memory. The JUN collar I got to replace it was only about 4 thou I believe.

What is yours measuring at?

[GTRPSI]

My Nitto collar was so tight i struggled to get the tomie oil pump on, i had to take the crank back to the machine shop to get the oil pump collar machined down.

Dont blame the collar, blame the person fitting it for not machining the crank down enough....

Too tight can be as bad as too loose, the crank needs room to flex and walk.

Edited December 17, 2014 by GTRPSI

[PRO_32]

Well my plan was to run some new gears be it reimax or some other local options most around the mid $400 mark in my standard pump and a collar but I'm just as worried about to tight as too loose and everyone seems to agree that Nissan may have left a large amount of clearance there cause of the flex from the i6 crank moving so much and pushing the gears into the pump housing. Ideally I would have liked to go a splined collar and gear set(2j style), but I have such limited info on the long term success of this solution for similar reasons.

Fwiw when I pulled of the standard pump on short drive nose clearance was .43mm so about .017 in old money. With hammering witnessed on both crank and gear.

[PRO_32]

So I guess the question I have is still what's factory clearance and is this what to aim for with new collar and gears or is this too loose? Limiter bashing is not really gonna be a problem as this motor is not really gonna be built for or treated like that.

[GTRPSI]

I think that what you are looking for is in the link below....

http://www.skylife4ever.com/2011/01/real-problem-with-rb26-oil-pump.html

[KiwiRS4T]

In defence of my NZ made crank collars I don't buy the argument about excessive clearances. As someone in the link above said do what we do - Loctite the screws in the pump. If you are going for the big revs make sure everything is balanced and get a new harmonic balancer.