Tomei Oil Pump Won't Fit With Crank Collar ?

[cobrAA]

What a bummer !!! Machinist assembled my whole bottom without realising the tomei oil pump won't fit with a crank collar... So what are my best option now ? Nismo oil pump, Nitto, N1 + reimax gear ?

i really wanted to run the tomei pump, like i never heard no where that i couldn't use a crank collar.. even Jun collar state it will work with tomei pump. I don't know what to think.

They tried with a std crank and the tomei pump fitted.

[cobrAA]

so basicly my choice are to decide between a NISMO or a REIMAX pump.. trying to see if both of them can accept the jun collar and then it's a question of flow.. one seems to flow 20 Liter more of oil and way bigger rotor ( reimax).

[Stixbnr32]

Pull it apart and install the Tomei.

If its a track car or you drive it hard with the N1 etc you will need to do it anyway. Any half decent RB engine builder would have known.

Nitto could be a go though - I have heard good things.

Do it once do it right.

Edited June 17, 2015 by Stixbnr32

[cobrAA]

Nitto and reimax/Nismo are my option. I will go for the lower volume. not sure i need 65l/6000rpm pumping. Yeah.. i wish my builder would've checked sooner. ANyways.

[jangles]

Nitto

[GTRPSI]

Funny enough exactly the same happened to my current build, Nitto collar and Tomie pump.

We had a nitto collar fitted, my machinist has fitted many collars in the past for others and we found out just like you after the bottom end was assembled that the collar was too big once we went to slide the pump on.

Dont muck around, its NOT a big job to get the bottom end dissembled and crank back out and get it machined back to size, it wont throw out your balancing.

I blamed it on the machinist not taking enough off the crank so the collar sat too high once it cooled down, however i could be wrong as i didn't mic up the outside of the Nitto collar before fitment to prove to myself for sure that it was not already too big.

Stay with the Tomie pump, its the only one made with external pressure adjustment, all the others cannot provide you with that, for that i rank it as the best internal pump you can run.

Also make sure you provide enough clearance for the oil pump collar to oil pump, the crank nose will flex and walk when pushing HP so make sure there is room to move, also if you have had the block mains tunnel honed the crank will sit a whisker deeper into the block.

Remember that the oil pump is positioned and centered on pins on the block.......

Edited June 18, 2015 by GTRPSI

[Stixbnr32]

My thoughts exactly.

def use the Tomei.

[cobrAA]

Once a collar is installed it can be removed ?

how much extra hours would you estimate to de-assemble and re-balance everything ?

I should've checked my stuff, but at the same time, theres a reason why i paid a mechanic and a machinist to do it for me, its because i don't know how to do it... so i can always make him pay for the extra hours as i can't see myself being blame for this mistake.

Edited June 18, 2015 by cobrAA

[GTSBoy]

Collar is like any other shrink-fit collar on a shaft. Removal is via grinder/cutting disc and careful avoidance of drinking too much metho.

[GTRPSI]

You dont remove the collar to fix it, leave it on the crank as is, get them to linish it down to the correct size, its the same procedure as linishing a crank.

Make sure they also mic up the flat sections and take care of them too while its out.

Dont forget to tape up all the oil feed holes before doing anything to stop dirt getting in, will save you having to remove the grub screws and going back through the oil channels with a rifle cleaner.

Make sure you clean the crank thoroughly before putting it back in.

[KiwiRS4T]

Once a collar is installed it can be removed ?

how much extra hours would you estimate to de-assemble and re-balance everything ?

I should've checked my stuff, but at the same time, theres a reason why i paid a mechanic and a machinist to do it for me, its because i don't know how to do it... so i can always make him pay for the extra hours as i can't see myself being blame for this mistake.

IFF the diameter of the collar is the only issue then there is no need to remove it - it can just be turned down to size and if everything is put back together in the same place then there should be little if any need for balancing. As a matter of interest do you have the diameter of the June collar? I haven't come across this problem as yet but would anyway expect the machinist to try the pump over the collar before fitting.

[cobrAA]

it was actually a crank collar bought on ebay ( I believe or was it on sau) 4 years ago from australia.. it was a ''jun spec'' and worked with my N1 pump.

[Shoota_77]

I had the same problem, JUN collar, Tomei pump and didn't fit. Same deal, my machinist had the oil pump as well as the crank/collar but he didn't pick it up.

I bought 2 collars, one local and the JUN. The local collar had heaps of clearance to the oil pump drive (prior to fitting to crank) whereas the JUN had perfect clearance. I can only presume the same as was mentioned above, the collar was heated to fit, was pressed on but then it didn't shrink back enough to give the right clearance.

Wish the machinist picked it up before i got to the point of fitting the oil pump...

[KiwiRS4T]

I had the same problem, JUN collar, Tomei pump and didn't fit. Same deal, my machinist had the oil pump as well as the crank/collar but he didn't pick it up.

I bought 2 collars, one local and the JUN. The local collar had heaps of clearance to the oil pump drive (prior to fitting to crank) whereas the JUN had perfect clearance. I can only presume the same as was mentioned above, the collar was heated to fit, was pressed on but then it didn't shrink back enough to give the right clearance.

Wish the machinist picked it up before i got to the point of fitting the oil pump...

If this is what's happening then its the machinist's fault. He hasn't removed enough material from the crank to allow the collar to return to its proper dimensions when cool. If he had double checked when the collar was on and found it didn't fit it would have been simple at this point to machine it down to suit.

[Shoota_77]

If this is what's happening then its the machinist's fault. He hasn't removed enough material from the crank to allow the collar to return to its proper dimensions when cool. If he had double checked when the collar was on and found it didn't fit it would have been simple at this point to machine it down to suit.

Yes, no (I agree), yes......

[cobrAA]

kinda sad to hear all these story... knowing that in fact it could've of worked but its not...

Anyways... i would've liked the idea of running a tomei pump because they seems to act a bit as a damper .. for the same reason i bought the coppermix clutch and their dampening effect, but oh well gotta move on. reimax gear ordered. I don't want to start a fight with the machinist either. what is done is done..

[Stixbnr32]

You will regret the reimax gear!

Heard many stories of them failing.

Good luck!

[Piggaz]

Explain the damper effect of the Tomei pump?

[Stixbnr32]

I had the same thought - please explain the coppermix clutch effect as well?

[cobrAA]

http://www.nismo.co.jp/en/products/competition/clutch/sctwin.html

This lowers the overall pressure on individual splines. It reduces wear to the input shaft and prevents disengagement problems. Having a center hub also makes installation easier than for single clutches by eliminating the risk of damaging the splines or misaligning the 2 discs during clutch assembly

just a better design overall than the os giken with a Damper vs their non damper clutch.

As for the pump, i didn't use the right word, but the 3 piece rotor design should help with vibration and gear breaking, i was told.