Oil pump?

[jdmser]

I just noticed when I reach full boost and start to pull really hard my oil pressure starts to fall off. The needle on the gauge starts to jerk as pressure drops. I was hoping that it was oil blowing by the turbo seals at high pressure(excuse for a new turbo), but I think it's probley the oil pump. Anybody else have any ideas? I did find some oil in the compressor outlet, but it was barely enough to coat two fingers. I don't seem to be loosing alot of oil.

[Carl H]

what engine and at what revs?oil pump backing plate might be comming loose......it has been known to happen.

[jdmser]

RB20 at about 4k

[Sil240]

is it the original oil pump or did you change it when you put the motor in?

[Carl H]

is this a 's1' rb20 with "rb20" embossed on the upper timing cover?if so the oil pump might be freewheeling and actualy loosing contact with the crank.some of the very early rb20's had this problem.

[integra7]

I think this is the problem Carl H is talking about....(I think it occurs on alot of early model RB motors)

Below you have a picture of a bad crank (this crank is actually from my RB25DET) and you can see the collar that drives the oil pump.

Below you have a picture of a good crank. As you can see, the collar that drives the oil pump is about 12mm WIDER than the bad crank above.

As you get into the higher RPM range, the collar that drives the oil pump will slip and you will basically lose all oil pressure.

Hopefully this IS NOT the problem you are having because, that would mean you need to teardown the whole motor and repair the crank.

Hope this helps.

[jdmser]

Its the original pump. I did take it apart and check the clearances before I put the motor in and it looked in good shape then. I guess its time to pull it apart. That sucks, I really wanted a new turbo.
Modified by jmdser at 2:37 AM 11/10/2005

[Carl H]

Its the original pump. I did take it apart and check the clearances before I put the motor in and it looked in good shape then. I guess its time to pull it apart. That sucks, I really wanted a new turbo.

Modified by jmdser at 2:37 AM 11/10/2005

did you locktite the oil pump screws? they are notorious for backing out on pumps.......and yah that crank bit is exactly what i was talking about, the crank drive is too short on some cranks and the oil pump starts to freewheel.

[jdmser]

Nope, totally didn't think about it. So worse case I need a pump and a crank. I don't trust the machine shops around here enough to let them weld on my crank. Does the RB25 have the same problem. Could be a good excuse to do a RB2.2 3 4 ? Best case I pull it apart locktite the screws and we're good to go.

[RBTALLY]

yes the rb25's the same problem in some years.. I michened a collar for my crank and had it pressed on and pined also . It did work but I was still worried about it so I have now switched to a external oil pump

[Kansei240sx]

where did you get or can get an external oil pump like that? and is it as efficient?

( in response to RBTALLY's post)

[integra7]

I've seen this happen on an RB26, and now on my RB25....and maybe on your RB20 now.....I think it's a problem on all earlier model RB's. No one knows for sure...

[SillyRB]

yes the rb25's the same problem in some years.. I michened a collar for my crank and had it pressed on and pined also . It did work but I was still worried about it so I have now switched to a external oil pump

Nice Is your car running with the new external oil pump set up ?I am intrested in following in your footsteps !

[johnzm]

can anyone tell me if there is an easy way to quickly determine if my motor is going to have this issue?

if i pull the timing belt stuf off the motor will i be able to see some of the pump drive on the crank, or will the pump have to come off before i can see it?

[gawdzilla]

the minimum you need to do is remove the oil pump. just by looking at the oil pump collar you can tell, if you know what you're looking for. you'll also be able to see the drive collar on the crank as pictured above once the pump is off. in order to pull the oil pump, you need to remove the pan. it may come out if you take out the bolts to the pan, but the front-most bolts of the pan are part of the oil pump.

[74260zt]

The front of the pan will have to be dropped at least 1" due to the oil pump presure spring assembly being that much down into the pan.....

The pump will not just slide strait off unless the pan is lowered enough to clear that spring assembly... (that blue hex bolt at bottom)



My Jun oil pump I set up for a external pick up.

[Phats]

BTW Just to let you guys knowm this is very informative, i didn't even know that this was a issue, and now i's got alot of info. Thanx

[Kansei240sx]

OK, last night i took off my dented oil pan, ( now undented ) and got down to my oil pump and looked at the crank collar.



The engine is out of a 1996 R33 and its a series two. Now, from what i've read the only engines that have the crank collar problem badly ( coming from skylinesdownunder and skylinesaustralia, say that its the R32's with the 26 and 20, and that they havent heard much of a problem coming from the RB25DET unless you have 500+ hp.

Now my question is, from you guy's perspective, does my crank collar look damaged much? i mean, the motor has around 40km on it and everything i've torn down on the motor so far has been in excellent shape, The bottom end is also rock solid.

If i am only really working for about 350-400 rwhp as my goal way later on down the road, should i be fine with the current oil pump and collar? and if not, WHO and how can i set up an external oil pump.

My mods list will be for the beggining, 3 inch exhuast from turbo back, Megan large fmic, MBC on 12 pounds, greddy intake manifold, adj fpr, intake bov and a few small other misc things.

[Carl H]

the real problem with the short crank drives is not the power output of the engine but the high revs the engine might endure.if you plan on spinning the motor out to redline on a daily basis you might want to consider modifying the crank snout.

[Kansei240sx]

So if i only max out at say 6900-7000 is that pushing it?

I still would like to know how to hook up and external oil pump and or where i can get one.

[eh?]

So if i only max out at say 6900-7000 is that pushing it?

I still would like to know how to hook up and external oil pump and or where i can get one.

Stock redline is around 7100 rpm (gauge reads 6800), so you should be ok

[Kansei240sx]

I was talking to a guy i know thats done this to similar cars that have a crank driven pump and he just put a not super thin layer, but moderate layer of JB weld on the inside of the oil pump where the collar meets it and it kept it snug and didnt ever want to freewheel. So ill give that a shot and that is suppose to help ensure the life of the oilpump and crank, and it also ensure that there arent any vibrations on that area which would cause wear in the first place.

[Carl H]

jb weld? are you fking kidding me?!you are gonna put jbweld on a part which can spin in excess of 8k rpm and is subject to insanely high pressure and other forces.dont be ghetto, fix it right or dont touch it at all.

[integra7]

If that was my motor, I would fix it. Why risk the chance of running it like that and losing the whole motor over it. It's a cheap fix.

I have the same problem with my motor (series 1 rb25det)...look at my previous post on this thread...

I should have my crank back in a few days.

[74260zt]

OK, last night i took off my dented oil pan, ( now undented ) and got down to my oil pump and looked at the crank collar.



The engine is out of a 1996 R33 and its a series two. Now, from what i've read the only engines that have the crank collar problem badly ( coming from skylinesdownunder and skylinesaustralia, say that its the R32's with the 26 and 20, and that they havent heard much of a problem coming from the RB25DET unless you have 500+ hp.

Now my question is, from you guy's perspective, does my crank collar look damaged much? i mean, the motor has around 40km on it and everything i've torn down on the motor so far has been in excellent shape, The bottom end is also rock solid.

If i am only really working for about 350-400 rwhp as my goal way later on down the road, should i be fine with the current oil pump and collar? and if not, WHO and how can i set up an external oil pump.

My mods list will be for the beggining, 3 inch exhuast from turbo back, Megan large fmic, MBC on 12 pounds, greddy intake manifold, adj fpr, intake bov and a few small other misc things.

That crank has the short drive on it. Look at the area that engages the oil pump drive, its very narrow, and from looking at the discoloration on it, it is only engaging halfway onto the oil pump drive gear.

Thats why they screw up... not much contact area.

[Phat_Optimo]

I was talking to a guy i know thats done this to similar cars that have a crank driven pump and he just put a not super thin layer, but moderate layer of JB weld on the inside of the oil pump where the collar meets it and it kept it snug and didnt ever want to freewheel.

That guy seriously needs a good . I would not take anymore advise from him.

The best way to deal with the crank with out going to an external pump is to have the flats extended. you can either buy the collar or have it welded and machined. I like the latter of the two but definately no jb weld.

[Kansei240sx]

alright alright, it sounded kinda fishy anyways, so ill stay away from the JB route, So it i do end up taking out my crank, what should i go to the machine shop to ask for? I dont really want to take it out, but, if i have to i dont have a choice,

i would actually really like to find out how to setup an external oil pump, no one has answered me on that, on what you need and how to do it.

[RBTALLY]

the external oil pump will run you about 1600.00 to 2000.00 buy the time you get the pump 650.00 drive kit 320.00 belt 50.00 ss lines and fittings 150.00 new balencer with a small block chevy blot pattern on th e front of it so the drive will bolt up 750.00 then just build the custom bracket to make it all fit... I will post up pics of mine in a few weeks as soon as I get my new ballencer from ATI

[Kansei240sx]

Dang, sounds like a lot of work, still interested though.

[JonPowell]

The best way to deal with the crank with out going to an external pump is to have the flats extended. you can either buy the collar or have it welded and machined. I like the latter of the two but definately no jb weld.

I don't like the idea of welding the snout on the crankshaft. To weld to a piece of forged steel like that with any success you will need ALOT of heat. Heat distorts metal. I am not cool with the idea of possibly warping the snout and rendering my crank useless & unbalanceable. JUN's collar is around $150 and isnt terribly hard to install. To em welding extra material onto the snout is akin to the JB Weld route.