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Topic Review (Newest First)
05-30-2013 05:00 PM
oldbogie
Quote:
Originally Posted by TylerS10 View Post
Its a 355 1970's block 4 bolt main studded solid roller setup "new build" probably only about 1000 miles on it.
Machine shop said the pickup is welded and ensures me the pickup height is correct.
Pan: Hamburger's 1099
Pump: Milodon HV 18760
New mechanical gauge and copper hose
"Machine shop said the pickup is welded and ensures me the pickup height is correct."

Not really, it is a means of being sure the pickup doesn't leak air at the join to the pump and that it doesn't loosen in the pomp bore and move around. The height from the bottom of the pan is established by measurement of the assembly, hopefully done before any welding and then welded properly. Then there is the issue of weld heat to the pump housing, if left in during welding often the relief valve spring is damaged by the heat. The heat can also distort the casting.

Welding on the pump is not all that simple of a thing to do, it's easy to perform more damage than good.

Bogie
05-30-2013 02:24 PM
68NovaSS Please don't run two threads about the same issue, they have been merged here.
05-30-2013 01:49 PM
TylerS10
355 Oil problems update

Well I find this kinda confusing I got of the phone with Hamburgers and they said my problem is you can't use a HV pump in there 7qt pan s10 pan. But jugs sels it in a kit with a HV pump. link below to kit

Hamburger's 1099K Hamburger's Oil Pans

Anyways the motor is coming out and back to the Machine shop
05-29-2013 04:12 PM
Richiehd Whatever......
05-29-2013 01:42 PM
TylerS10
Quote:
Originally Posted by oldbogie View Post
Except for the hot fluctuations this sounds perfectly normal. Brings some more thoughts:

- Is the gauge electric or mechanical? If electric have you checked the sender?

- Was the pickup tube brazed or welded to the pump? If so was the relief valve spring removed before heating?

- Again the distance between the pickup and the bottom of the pan, this should be 1/4 to 3/8ths inch.

- Possibility that the pickup tube is cracked or doesn't fit into the pump tightly? 7000 RPM is a high vibration environment; it is not unusual for the pickup tube to fatigue out especially if it isn't buttressed with extra support back to a solid mounting point like the pump cover bolts or the pump mounting bolt.

- Insufficient drain back at high RPM is starving the pump? What, if anything, was done to the block to change the factory drain back holes?

- Does this engine have a windage tray and stripper? What about trap doors and other gadgets in the pan to collect and hold oil by the pick up?

- What is the pump's capacity i.e. stock SBC, stock BBC, high volume, high pressure, high volume and high pressure?


Bogie
I'm going to try a standard volume oil pump and the Hamburgers pickup before I actually pull the entire motor out complacently.
05-29-2013 12:57 PM
lg1969 Hey TylerS10, Good luck on the project you are working on. Glad to know the oil pressure is back.

louis
05-29-2013 12:55 PM
oldbogie
Quote:
Originally Posted by TylerS10 View Post
Its a 355 1970's block 4 bolt main studded solid roller setup "new build" probably only about 1000 miles on it.
Machine shop said the pickup is welded and ensures me the pickup height is correct.
Pan: Hamburger's 1099
Pump: Milodon HV 18760
New mechanical gauge and copper hose
Where I'm heading is:

1) The oil in circualtion at high RPM is not draining back fast enough. A high volume pump and wide clearances without opening up the drain back passages and/or a lack of windage tray and crank scraper could all contribute to oil becoming entrapped by the top end or the spinning crank.

2) A high vibration mode at high RPM is causing the intake pipe to the oil pump to open a crack admitting air with the oil.

3) The pump goes into cavitation which is what anti-cavitation grooves in the pump cover are supposed to eliminate.

4) The pickup is too high above the pan bottom to where at high RPM a vortex forms in the oil being sucked into the inlet bringing air along with it. This is a common problem with deep pans. Often people forget to match the pan with a deep pick up or actaully done correctly the oil pump itself is extended into the pan with a normal length pick up.

5) A lack of suitable or inoperative oil control gates in the pan are allowing oil to escape the pickup area leading to the injstion of air.

6) At high RPM the relief valve spring becomes unstable resulting in surging that then allows the relief valve to cycle.

Something is obviously going wrong at high RPMs and this would certainly get my attention as it has yours. It looks like a tear down will be needed to pin point what's going on.

Bogie
05-29-2013 12:10 PM
TylerS10
Quote:
Originally Posted by Richiehd View Post
Find something else to worry about, you've got a non issue. Or put a light in instead of a gauge, then you will stop looking at it. 10 psi per CI.
LOL ok will do. Just to be safe I'm having a local Race Shop who respects the machine shops builder to check everything. He recommend I go to a thicker oil because my clearances were set a little loose for N2o.
05-29-2013 11:57 AM
Richiehd Find something else to worry about, you've got a non issue. Or put a light in instead of a gauge, then you will stop looking at it. 10 psi per CI.
05-29-2013 10:48 AM
TylerS10
Quote:
Originally Posted by oldbogie View Post
Except for the hot fluctuations this sounds perfectly normal. Brings some more thoughts:

- Is the gauge electric or mechanical? If electric have you checked the sender?

- Was the pickup tube brazed or welded to the pump? If so was the relief valve spring removed before heating?

- Again the distance between the pickup and the bottom of the pan, this should be 1/4 to 3/8ths inch.

- Possibility that the pickup tube is cracked or doesn't fit into the pump tightly? 7000 RPM is a high vibration environment; it is not unusual for the pickup tube to fatigue out especially if it isn't buttressed with extra support back to a solid mounting point like the pump cover bolts or the pump mounting bolt.

- Insufficient drain back at high RPM is starving the pump? What, if anything, was done to the block to change the factory drain back holes?

- Does this engine have a windage tray and stripper? What about trap doors and other gadgets in the pan to collect and hold oil by the pick up?

- What is the pump's capacity i.e. stock SBC, stock BBC, high volume, high pressure, high volume and high pressure?


Bogie
Its a 355 1970's block 4 bolt main studded solid roller setup "new build" probably only about 1000 miles on it.
Machine shop said the pickup is welded and ensures me the pickup height is correct.
Pan: Hamburger's 1099
Pump: Milodon HV 18760
New mechanical gauge and copper hose
05-29-2013 10:04 AM
lg1969 When It reach from idle to about 1500 RPM the oil pressure will swing that much when it's at operating temp from 35 psi - 65 psi.
05-29-2013 09:14 AM
oldbogie
Quote:
Originally Posted by TylerS10 View Post
Cold start 60psi, on the highway cold 70psi @ 3500 rpm. Once the oil gets good and hot it will drop to 55-60psi @ 3500 rpm. Exit the highway come to a light when hot 25psi in gear, neutral about 38psi. 2nd gear pull to 7000 rpm while hot it ill spike around 70psi then drop to 25-35 and fluctuate to 60 at times then back down kinda all over the place.
Except for the hot fluctuations this sounds perfectly normal. Brings some more thoughts:

- Is the gauge electric or mechanical? If electric have you checked the sender?

- Was the pickup tube brazed or welded to the pump? If so was the relief valve spring removed before heating?

- Again the distance between the pickup and the bottom of the pan, this should be 1/4 to 3/8ths inch.

- Possibility that the pickup tube is cracked or doesn't fit into the pump tightly? 7000 RPM is a high vibration environment; it is not unusual for the pickup tube to fatigue out especially if it isn't buttressed with extra support back to a solid mounting point like the pump cover bolts or the pump mounting bolt.

- Insufficient drain back at high RPM is starving the pump? What, if anything, was done to the block to change the factory drain back holes?

- Does this engine have a windage tray and stripper? What about trap doors and other gadgets in the pan to collect and hold oil by the pick up?

- What is the pump's capacity i.e. stock SBC, stock BBC, high volume, high pressure, high volume and high pressure?


Bogie
05-29-2013 09:06 AM
lg1969 What you describe is normal. When cold it would go up to 80 psi. At operating temperature it should be 55-65 psi. At idle around 25-35 psi. You have fix the problem
05-29-2013 08:34 AM
TylerS10
Quote:
Originally Posted by Richiehd View Post
I think I would try a new distributer or at least mic the housing and compare to a new one, before I pulled the motor. You said thats where your problems started. How much is "low oil pressure"?
Cold start 60psi, on the highway cold 70psi @ 3500 rpm. Once the oil gets good and hot it will drop to 55-60psi @ 3500 rpm. Exit the highway come to a light when hot 25psi in gear, neutral about 38psi. 2nd gear pull to 7000 rpm while hot it ill spike around 70psi then drop to 25-35 and fluctuate to 60 at times then back down kinda all over the place.
05-29-2013 08:19 AM
Richiehd I think I would try a new distributer or at least mic the housing and compare to a new one, before I pulled the motor. You said thats where your problems started. How much is "low oil pressure"?
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