Advice needed on spun bearing.

[kyhunting]

I have found the source of my 0 psi oil pressure. I have a spun #5 rod bearing. The engine has about 10 hours on it. It is in my race car. I was at Sebring in Feb. and lost oil pressure on the third day. No other damage. The car has a sump tank in the front with a 12AN hose on the oil filter side and a 20AN (I think it is a 20AN, its alot bigger than the 12AN) on the return side. A 6" canton oil filter that had a collapsed filter element inside. I took the oil pump apart and it looked fine (I have not checked the specs). I am assuming this is an oil starvation issue. I had good oil pressure right up until it went to zero. No other indications. I have been thinking of what could be the culprit. Oil return hose collapsing, oil filter failure, oil pump failure. I am replacing the oil pump with a new carrera pump, replacing the canton filter assembly with something else (I haven't settled on the replacement yet). I really would like to know that I have corrected the problem before I go out on the track again. Any advise would be appreciated.

[Steve@Rennsport]

Hi,

Indeed, losing a #5 (or #2) rod bearing is due to oil starvation.

With a front mounted tank, I would be using AN16 hose on the filter side and AN20 on the return. Further, I'd be using a larger oil pump with more capacity such as a 930 or GT-3R one.

Look for hose collapse or filter failure, pump failures are rare unless it was starved.

[Flieger]

Need to have an internal spring in the suction lines...

[kyhunting]

Internal spring. How does that work? Please explain this to me. Is it for the entire lenght of hose, how do you install it, where do you purchase it? Thanks

[Steve@Rennsport]

Aeroquip sells them.

These are needed inside a suction line to prevent collapse. These get inserted into the whole length of the line feeding the oil pump.

[kyhunting]

From my internet search... It looks like -16 is as large as the internal springs go. All seem to come in 20' length. Anyone suggest a vendor. I have found that summit and jegs have them.

[TimT]

We sometimes run aluminum pipe from the front oil tank to the rear bulkhead, just short pieces of -16 or -20 one from the tank to the beginning of the pipe (short less than a foot) then a piece from the rear bulkhead to the engine oil fitting.

The pipe won't collapse, and the short pieces of an wont collapse since they have slight bends..

FWIW it is less expensive to run get a piece of aluminum pipe, and weld on some an ends, than is to run the braided hose + internal spring, and this is counting the two extra fittings you need...