rb26 jun oil pump broke! WHAT THE F!!!!!!!

[SullivanRacing06]

so driving home from a friends place last night and i notice my oil pressure jumping, then my oil pressure light comes on and so i shut it off. i crank it and theres a ticking comming from the lower t belt area (oil pump drive broke) and this all happened on a brand new r33 n1 crank.


any clue if they stand behind their products?????

i know tomei guarantees there pumps to never break..... dose jun do the same?

[Sil240]

Did you have a collar on your crank?

[julio]

Did you have a collar on your crank?

and this all happened on a brand new r33 n1 crank.

Wow, what kind of driving were you doing to it when it broke?

[SullivanRacing06]

my low pressure oil light (goes on when oil pressure drops below 20-25psi) came on after i did a 3k 2-3 shift, nothing crazy!

im still takin it easy on my motor bc i just built it.... this pump came off my last 26, maybe it had issues from the last motor?

[74260zt]

and this all happened on a brand new r33 n1 crank.

Did you have a collar on your crank?

That crank has a wide flat already on it...

Thats the same pump and crank I'm running. No issues so far...

[julio]

my low pressure oil light (goes on when oil pressure drops below 20-25psi) came on after i did a 3k 2-3 shift, nothing crazy!

im still takin it easy on my motor bc i just built it.... this pump came off my last 26, maybe it had issues from the last motor?

Yea, that's pretty weird. The only reason I hear of them breaking (any oil pump gear) is either from fatigue or smacking into the rev limiter. You'll have to post up some pics of the pump when you take it apart so we can assess what the mode of failure was.

[SullivanRacing06]

i was driving normally when i saw the low oil pressure light come on. no were near the red line


towed the car home at 945 last night had motor n transmission out around 1130(our friend captain had us sailing thru the pull quick) planning on puting the engine on the stand and start tearing it down to install the new bearings and tomei pump

while the head is off im having a three way valve job done, installing supertech springs and retainers, new valve seals and 264 hks cams so my head will flow better..

[Carl H]

perhaps the backing plate bolts on the pump came loose...i always tear apart the pump and loctite the screws back into place.

[disrupt]

did you have the bottom end balanced? what are you running as a dampener?

[toadx8u]

shoulda had your motor balanced...

[FAST-DATSUN]

Once you get it apart you will find you should have put on a crank collar. it all looks good until you est everthing and find out only about 1/16 to 1/8 is actuall hitting the rotor of the pump....

Post pic of the broken rotor and we can see the engagment of the collar. also need to check the pick-up and pan for problems.. Many parts are being sold here under wrong info and people sell lack proper knowledge of what there selling.

[julio]

Once you get it apart you will find you should have put on a crank collar. it all looks good until you est everthing and find out only about 1/16 to 1/8 is actuall hitting the rotor of the pump....

Post pic of the broken rotor and we can see the engagment of the collar. also need to check the pick-up and pan for problems.. Many parts are being sold here under wrong info and people sell lack proper knowledge of what there selling.

Come on people, read the post...

and this all happened on a brand new r33 n1 crank.

[SullivanRacing06]

i pulled the pistons n rods apart, weighed and balanced them

compared the r33 crank collar to a jun collar and mine was the same size

cross reffd the part number and it came up as a r33

im currently in a argument with jun about the pump



been in orlando / tampa/ miami so i havent had time to pull apart yet

hopefully ill be able to pull it out and apart on monday night.. my girl wants to help so i guess well see how far we get haha, get distracted easily..

[SullivanRacing06]

im ordering a tomei as soon as glenn gets back to me about the price....... checkin to see if the bearings wer effected, i caught it rite as pressure dropped under 20, if they look ok then ill install another set of std acl race bearings and just be waiting on the tomei to arrive then ill have it back together

also my trannys input shaft bearing has been makin a hell of a noise im thinking that could of caused this entire mess....

vibrations goin thru the crank from the transmission

[Sil240]

If I were you I would just switch to a OEM pump or get an external pump with a Crank pulley with a Gear drive.

How much does a Tomei pump cost?

[Carl H]

is the pump actually damaged?
having oil pressure less than 20 psi isnt too far fetched...when the oil in my car is hot it will drop down to as low as 1.2 bar when it normally sits at 1.5 bar.

[SullivanRacing06]

yea i restarted the car for a second and the pump was making noise.

tomei's retail between 1500-1750 he said he can get me one between 900-1100

[SullivanRacing06]

is the pump actually damaged?
having oil pressure less than 20 psi isnt too far fetched...when the oil in my car is hot it will drop down to as low as 1.2 bar when it normally sits at 1.5 bar.

the oil pressure in my 26 has always been 110-120 start up and will drop to around 50 at warm idle (700-750)rpm @ 155deg and with the a/c on 195deg it will drop to 45psi

my oil temps never go above 140while driving and will stay around 160 on auto x tracks

[toadx8u]

that pressure sounds really high to me...just saying...its one thing to have a high volume oil pump(good thing) but a high pressure oil pump can mess things up inside the engine if its not designed for it...it sounds like maybe jun coulda sent you the wrong kinda pump...idk just what it sounds like to me....my rb never had over 50 psi for oil pressure like carl said it usually hangs around 20 at idle...

[SullivanRacing06]

the jun pump relief spring is 120psi so i dont think any thing is wrong there

the pick up and pan had nothing in it


has acl race bearings and a tomei 1.5mm reducer to the head and rotella 15-40, i dont see anything wrong with to much oil pressure............

[toadx8u]

why are u running diesel oil in your car with much tighter tolerances?

[gawdzilla]

too much oil pressure is bad. it stresses bearings and the pump. running oil that is too cold is also bad. 140-160 is cold for oil. that's basically like driving on a motor that has not been warmed up yet.

[WhatsADSM]

Throw in another vote for pressure around 20psi at idle on a rb26. 55 at idle sounds CRAZY high.

[gawdzilla]

yep. 20-25 psi range for warm idle

[Darius]

+1 for 20 psi @ idle and normal operating temp.

[ItzGenX]

And exactly what pumps are all these people claiming their psi in the 20's using? Can't really compare a stock/n1 to a 1000 dollar pump that outflows them by leaps and bounds.

His oil pressure may be way higher with a combination of more flow and that thick diesel oil being used. The oil temps seem a bit low while driving though. Is there an oil cooler without a thermostat installed or something?

[R32ONP]

the thicker diesel oil would make more pressure and also depending how old the oil is will make more pressure wen the oils old and thick and has crap in it....imho 55 is too high on idle lol..but could be wrong...i get around 1-2 bar hot on idle and 4-5 bar max........pressure isnt everything tho..alota pressure can be bad as it could airate the oil....the oil volume is alot more important than the pressure....

just my 2 cents

[julio]

yep. 20-25 psi range for warm idle

+1 with an N1 pump.

[toadx8u]

And exactly what pumps are all these people claiming their psi in the 20's using? Can't really compare a stock/n1 to a 1000 dollar pump that outflows them by leaps and bounds.

His oil pressure may be way higher with a combination of more flow and that thick diesel oil being used. The oil temps seem a bit low while driving though. Is there an oil cooler without a thermostat installed or something?

flow is one thing...pressure is another...thats why a 5-9psi fuel pump can FLOW just as much as a 40-60 psi pump...often times more cause it doesnt have to achieve the pressure that the high pressure pump does

there are 2 kinds of oil pumps that most companys make...HIGH VOLUME and HIGH PRESSURE....high pressure is designed for a motor thats built LOOSE not tight like the factory specs are...it could be such a thing that jun sent him the wrong kind of pump or he may have ordered the wrong part number not realizing it was high pressure...

im also guessing he built this motor to factory specs therefor it cant handle the pressure that the pump was putting out...the pump was being backed up and over worked and eventually failed...if you tell jun you were running 15-40 they are gonna laugh in your face and tell u to eat it and buy a new pump...the pump is not designed to move oil of that viscosity...

the brand of pump and how much you pay for it has nothing to do with how much pressure it puts out...all the companies know what the factory specs are and they may up the pressure some but what they are going for is more flow...more oil flow means less wear on parts...which leads to longer engine life...now go adding a s*** ton of pressure and it adds stress to places it doesnt need to like the journal bearings and the cam bearings...

so swinging your 1000$ oil pump stick dont amount to a hill of beans...cept that your paid oh about 800$ more for your oil pump than i did and mine hasnt failed yet...

i still attribute most oil pump failures to a lack of engine building know-how...if you are going into the motor to replace parts on the rotating assembly (IE: rods & pistons) then guess what you just f*%ked up the balance the motor had from the factory...no harmonic dampener in to world is gonna help that not even the ross racing products...you need to send the whole rotating assembly (balancer to clutch) to a balance shop where they will weigh each piece and spin balance it with everything else...determine where it needs weight added and weight taken out and then send it back to you after balance has been achieved...it only costs about 300$ and its a great piece of mind...i have been building motors for about 15 yrs now and i have never had a motor fail due to a rotating assembly issue...

sulli good luck with your repair

RANT OVER!!!

[R32ONP]

dayyymmm +1 for the knowledge in that post ^^^^^^^^^^^^^