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Topic Review (Newest First)
01-31-2013 08:59 AM
lg1969 Before you start taking it apart try to fine another distributor and replace it.
01-31-2013 08:54 AM
ap72
Quote:
Originally Posted by Richiehd View Post
Why are you mixing oil weights? You live in Florida, you have a motor that probably has a little extra clearance in the bearings. Use a 20-50W Brad Penn RACE oil if you need the ZDDP. or Valvoline VR1.
I agree, no need to mix a magical concoction, but I'd go with 5W40 Mobil 1 unless you have an aggressive flat tappet cam. Also, think about changing your pump if you didn't when you rebuilt the engine, the pumps can wear a lot depending on the oil/filter you used in the engines prior service life.
01-31-2013 08:40 AM
Richiehd
Quote:
Originally Posted by bigdog7373 View Post
Im pretty sure 5qts of 20w50 is going to be wayyy to thick. That's what we use for hydraulic fliud in our commercial mowers and the stuff is very thick.
Whatever.....read my last post!
01-31-2013 06:17 AM
bigdog7373 Im pretty sure 5qts of 20w50 is going to be wayyy to thick. That's what we use for hydraulic fliud in our commercial mowers and the stuff is very thick.
01-31-2013 05:10 AM
Richiehd Why are you mixing oil weights? You live in Florida, you have a motor that probably has a little extra clearance in the bearings. Use a 20-50W Brad Penn RACE oil if you need the ZDDP. or Valvoline VR1.
01-30-2013 01:31 PM
bigdog7373 Alright so I put 4qts 10w40 and 1qt 20w50, then my zinc additive which was surprizingly thick.
Cold idle neutral: 50psi, in gear 45psi
Hot idle neutral 10psi, in gear 6psi
Crusing at 50mph 23-26psi.
Not too bad. Obviously there is something wrong but at least I can drive it without worry now.
I'm thinking in the near future I will pull the engine and trans and sell them. Ive wanted to do an ls swap for a while plus I have a 4speed muncie that I'm dying to put in.
01-30-2013 12:35 PM
bigdog7373 Going out now to change the oil. I'll post results in a few.
01-30-2013 10:33 AM
vinniekq2
pan gasket in car replacement

Quote:
Originally Posted by bigdog7373 View Post
Vinnie, is that a 2nd gen fbody in your pic? If so have you even changed the pan with the engine in the car? Like I said before I can't pull the engine cause of my pita hoa people.
Its a C-3 with a 434 stroker,7 qt pan. The center link is quite close,other than that I could probably change the pan in the car. I would not do that. I would take the engine out and put it on the stand.If I have to do something else like a crank seal or timing chain,its easy with the engine on a stand.
I use a roller cam so I would inspect the gear and back of the manifold. Maybe do a quick wash and detail before it goes back in. Thats just me though,,
01-30-2013 09:35 AM
bigdog7373
Quote:
Originally Posted by vinniekq2 View Post
If you bother to change the oil pump,then add a bigger pan.
Vinnie, is that a 2nd gen fbody in your pic? If so have you even changed the pan with the engine in the car? Like I said before I can't pull the engine cause of my pita hoa people.
01-30-2013 09:32 AM
bigdog7373
Quote:
Originally Posted by ap72 View Post
20psi at 1500 RPM is NOT that low. its below average for a new crate engine but many people have built engines with this pressure or less. I'm tempted to think he reused the oil pump and a worn oil pump will have such a poor seal that it will have little pressure at low speeds- the other option is that he is just running larger clearances, and at one time that was a VERY common thing to do.

I wouldn't go too much thicker and I'd give serious thought to buying a better pump (m155hv from melling is about $40 without the pickup, which is about another $10). You may have other issues (leaky pick up, clogged pick up, leaking oil main, etc.) but it is possible for everything to be fine and just have low oil pressure if you have large rod, and main, or lifter, or cam clearances.
I'll see how it does with the new filter and oil but I may end up changin the pump. I have a change the pan gasket anyway cause its leaking a little. I can't remeber what pump I used or if I even changed it. Its was a while ago. I had a thought that maybe I left out the gasket that seals the pump to the block? Seems like it could cause this problem. I don't know how I could get the pan off with it in the car though.. For the pump I would think I could pull the old one out and let the drive shaft drop out with it, then just put the shaft on the new pump and slide it up in. This way I wont have to do anything from above.

Quote:
Originally Posted by snakebit68 View Post
Just my opinion...but I think adding thicker oil to boost pressure would only be masking a more serious issue. Low oil pressure is an indication of an underlying issue. First, make sure your sending unit is functioning properly and then verify your gauge is reading correctly. If so, its time to open it up and check oil returns, pump pickup, oil pump...and then on to clearances. But don't ignore it. My buddy tried the thicker oil trick to boost pressure...it worked...until he made a pass at the track and it seems the thicker oil was unable to return to the pan fast enough at 7000 RPMs and "BANG". There are alot of details and steps involved to diagnosing your issue...but don't put a bandaid on it, please.
Just my opinion...no better then anyone else's
I'm not looking to mask the problem. But if going from 30 to 40 weight oil will fix it I don't think that's really considered masking it.

Quote:
Originally Posted by snakebit68 View Post
I was a little struck by the fact that you stated your engine was bored .080 over. I was under the impression that a 383 is a 350 block that is .030 over with a 400 crank and flywheel...bringing the cubic inches to 383. If your block is .080 over you may never get good oil pressure. I believe the limitations on boring a 350 block border around .060 and that is pushing the cylinder wall dangerously close to being to thin. Those cylinder walls are surrounded by water jackets, ports in the block that allow coolant to dissapate the heat of the cylinders. Are you certain of the bore?
Wrong thread lol
01-30-2013 09:09 AM
snakebit68
Low oil pressure

I was a little struck by the fact that you stated your engine was bored .080 over. I was under the impression that a 383 is a 350 block that is .030 over with a 400 crank and flywheel...bringing the cubic inches to 383. If your block is .080 over you may never get good oil pressure. I believe the limitations on boring a 350 block border around .060 and that is pushing the cylinder wall dangerously close to being to thin. Those cylinder walls are surrounded by water jackets, ports in the block that allow coolant to dissapate the heat of the cylinders. Are you certain of the bore?
01-30-2013 08:53 AM
vinniekq2 If you bother to change the oil pump,then add a bigger pan.
01-30-2013 08:46 AM
snakebit68
low oil pressure

I agree with ap72. Dead on with his thoughts, as I was thinking the same. Besides, I've had alot of small block Chevys and they have always seemed to run a bit low on pressure at idle. As long as the pressure comes up upon acceleration to a reasonable level he should have no problems. But if the problem persists, dont ignore it
01-30-2013 08:30 AM
ap72 20psi at 1500 RPM is NOT that low. its below average for a new crate engine but many people have built engines with this pressure or less. I'm tempted to think he reused the oil pump and a worn oil pump will have such a poor seal that it will have little pressure at low speeds- the other option is that he is just running larger clearances, and at one time that was a VERY common thing to do.

I wouldn't go too much thicker and I'd give serious thought to buying a better pump (m155hv from melling is about $40 without the pickup, which is about another $10). You may have other issues (leaky pick up, clogged pick up, leaking oil main, etc.) but it is possible for everything to be fine and just have low oil pressure if you have large rod, and main, or lifter, or cam clearances.
01-30-2013 08:23 AM
snakebit68
low oil pressure

Just my opinion...but I think adding thicker oil to boost pressure would only be masking a more serious issue. Low oil pressure is an indication of an underlying issue. First, make sure your sending unit is functioning properly and then verify your gauge is reading correctly. If so, its time to open it up and check oil returns, pump pickup, oil pump...and then on to clearances. But don't ignore it. My buddy tried the thicker oil trick to boost pressure...it worked...until he made a pass at the track and it seems the thicker oil was unable to return to the pan fast enough at 7000 RPMs and "BANG". There are alot of details and steps involved to diagnosing your issue...but don't put a bandaid on it, please.
Just my opinion...no better then anyone else's
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