Ok. I spun my crank bearings 500 miles after completion. The shortblock was done by a machine shop. A 2nd machine shop just got done looking at the assembly and its oil starvation (which I already knew). They dont know how though. I prelubed the engine with oil before install. I changed the oil twice with regular Dino oil before the 500 mile changed to Synthetic Mobile 1. It ran fine up until i started getting on it hard and rev through the gears. Thats when it spun. So Im guessing something happened at High Rpms. Everything was brand new in the shortblock and partly in the long block. Oil pump was new with steal pick up (still attached to the pump) with a HIGh pressure spring.

HEre are some comments on another board.. What do u think? What could have happened at high Rpms to starve the oil.. thoughts on packing the pump with grease.. ?

"Momentary oil starvation is most likely cause by windage of the oil, and then air bubbles being picked up by the pump and transferred to that particular bearing. If I remember correctly, this happened after a high rpm bash right???"

"Did you pack the oil pump when you installed it. If you didnt pack it with grease then this would have happened. My friend went through 2 motors this way... each was about 200 miles on them. Reason being is this creates pressure and slings oil up immediatley"

 

Sounds like installer error if the bearings just spun and didn't break anything else. The oil starvation could ahve been caused by improperly installed cam bearings, RTV in the oil galleys, not cleaning the block properly or at all, and number of things. But, they generally drive back to installer error.

And i've never heard of packing a oil pump with grease ! That seems like a dumb idea. Oil goes in an engine, not grease. If you prime it, the oil pump is already flowing oil. Grease seems pointless and retarded. I've built numerous engine and have never packed an oil pump.

-Shannon

 

lol? why would you pack greese in the oil pump
How was your oil pressure at high rpms?

 

Yeah i never heard of the grease thing but Hey the bearing spun so something wrong happened so im taking all comments seriously.

The Oil pressure was high when it spun. It has a high pressure spring in the pump (could that cause it somehow?).
THe windage tray in the oil pan had to be moved almost 1/2 inch lower (closer to the bottom of the pan) so that the Rod bolts would not hit the windage tray. Could the lowering of the windage tray cause it? Some people dont even use a windage tray.
Oil pump is new. All parts / bearings were new except for the cam itself.
Oil was fine first 500 miles, car ran normal. The Block was hot tanked and I checked it myself. Ran a magnet through it. THe galleys looked fine too and i think it would have spun the bearing before 500. Cam bearings not properly installed or clearanced i dont know..

 

I have never done it, but the practice of packing the oil pump with lube is shown in the popular Mike Mavrigian book of rebuilding the LT1/LT4 engine. I really don't see this being necessary if you use a pre-oiler tool.

 

Are you by chance running a high volume pump in a stock pan?

 

ya, whats the part number of the pump u are using?

 

what kind of forged rotating assembly are you using? How high are you spinning it and what were your bearing clearances?

 

Very good point. If you are using a HV pump it could be your cause. I ordered the summit rebuild kit and it normally comes with the HV pump, but I just asked for the normal melling pump and the steel part instead of the plastic piece. I didnt know the name of it, but the customer service agent knew exactly what I meant. Any other info about the pump that I should know of so I dont do something stupid? Also, whats that steel piece called?

Thanks, didnt mean to jack your thread.

 

The Pump is a stock LT1 pump. I didnt want a HV for that reason.

Bearing clearances were done by the machine shop... no way to tell the clearance after the bearings spun.
Rotating assembly is a Eagle Crank (Cast), SIR Eagle Forged rods, Speedpro lightweight forged pistons, plasmamoly rings.

The Steel piece ur talking about is the oil pump pick up. Yes i bought a steel 1 and welded it to the pump. I took the spring out before welding to so as not to melt it.
My Car spins to 6400rpms..

 

I was running a HV pump in a stock pan. NOT A GOOD IDEA. It was fine when I only had 378rwhp but last summer I stepped up with an LE2 H/C package and it was probably putting out 420rwhp. I was only able to make 2 passes at the track before it starved the motor of oil.

Maybe even with the high pressure spring u sucked your pan dry?

 

Unless it spun every bearing you can tell what your clearances were set at by checking the ones that didn't spin and making sure all the bearings were the same size.


You could also ask the shop if they did a build sheet. I had my machine work done and checked by another shop and neither shop realized my clearances were to close. My machine work was done for stock clearances which thanks to this board was caught.

The other thing I just heard is that some of the eagle and Scat cranks do not have their oiling holes in the proper location and can cause oil starvation at higher rpms especially if you don't have the right pump for your system.
I had never heard this before and I'm having mine checked out. I'm not sure if it's true or not but from what I was told the holes drilled thru the crank are not in the proper location to line up with the ones in the rod bearings.