GoCiggie31

Engines 502 mag 1991 in heavy deep V, Cig Bullet.

Had port engine long block rebuilt (by a very reputable shop). Ever since rebuild, the remote filter (stock) and hoses really never got hot to the touch, not like the strd engine that was not rebuilt.
1st couple of hrs during break in never really wound it out.
change engine oil and filters after <2 hrs of very carefull running varing rpms, no sustainted hot-runs. cut open filter and look clean.
replaced all the guages and senders and still big difference in oil temps- rebuilt engine oil temp still luke warm to touch.
rebuilt engine never got past 140 oil temp, while the non-rebuilt engine would peg 260 on most recent sustained hard run-5 min. now oil pressure is below 15lbs .

I am now running 15-50 mobil 1 engine oil ever . -change 2X in <7 hrs.

-could this be a problem with an internal bypass valve during assy by shop?
-faulty oil filters?
-could any of this be related or different issues?

btw...water temp never gets past 160 and water pressure <25 lbs.
oil temp sensors located on remote oil filter housing

any help would be very much appreciated.
Thanks

mrhorsepower1

give me a call when you get a chance. I will be happy to give some advice. (216) 398-8500

Best Regards,

Dean Gellner
Gellner Engineering Marine Power

blue thunder

I would guess bypass valve problem. Oil was being redirected past oil filter and probably cooler too. When you did run it hard the oil temps probably went way past acceptable and the main bearings got wiped out. Just a guess though, I am not certain of the oil routing on your block. I personally block the bypass valves so 100% of the oil gets cooled and filtered. I just make sure to run a good filter like a baldwin 1441 that has a built in bypass valve.

The other thing to consider would be oil lines hooked up wrong.

GoCiggie31

Dean,
It was very nice talking with you and thanks for the info-I will follow up with U.

GoCiggie31

BT,
sure sounds like what happened regarding the bypass-I am wondering if a little was leaking past as the hoses warmed up a bit and the oil filter was getting some oil through when I opened it up.
I will double check on my oil lines and match with stbrd engine as I don't think I could switch them-all oem and I think they all have specific fittings...but I guess if it can be done, leave it to me

I will be yanking the engine out tomorrow and double checking my routing as I don't want this to happen again. Boy, talking about a learning experience...yawow-cha-ching!

Thank you both for your response-very much appreciate.

gc31

blue thunder

I've had too many learning experiences in this regard Gocig! The bypass valves are actually designed to leak, they are pressure differential valves. When the engine is cold, the differential thru the filter and lines is high relative to pump pressure, and the bypass dumps oil past the filter to keep good flow thru the bearings. As things heat up and the differential drops due to viscocity reduction in the oil and clearances opening, less leakage past the valve (less differential). If the valve was missing or spring out of position, the leak past the bypass valve would consume all oil and none would go thru the filter and/or cooler. That is why I plug my bypass valves. If you run nice at cold engine temps you do not need the bypass valves. I use a filter with bypass in case of something severe like filter collapse.

I would look hard at the oil line routing as well.

BT

mrhorsepower1

Very nice speaking with you also!

1BIGJIM

iTrader: (1)

I would also agree to check the oil lines. I put mine on wrong one time, and the out come was not good.