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Old 05-29-2013, 08:09 AM
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I'm going to pull the distributor when the composite gear comes in and putting the O rings back in and see if she is happy. If not I guess the motor will need to come out and check the oil pump pickup to see if itís right.

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Old 05-29-2013, 08:19 AM
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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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Old 05-29-2013, 08:34 AM
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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.
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Old 05-29-2013, 09:06 AM
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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
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Old 05-29-2013, 09:14 AM
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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
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Old 05-29-2013, 10:04 AM
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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.
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Old 05-29-2013, 10:48 AM
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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
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Old 05-29-2013, 11:57 AM
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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.
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Old 05-29-2013, 12:10 PM
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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.
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Old 05-29-2013, 12:55 PM
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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
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Old 05-29-2013, 12:57 PM
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Hey TylerS10, Good luck on the project you are working on. Glad to know the oil pressure is back.

louis
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  #27 (permalink)  
Old 05-29-2013, 01:42 PM
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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.
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  #28 (permalink)  
Old 05-29-2013, 04:12 PM
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Whatever......
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Old 05-30-2013, 01:49 PM
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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
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Old 05-30-2013, 02:24 PM
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Please don't run two threads about the same issue, they have been merged here.
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