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Sun Feb 23, 2014 7:12 pm

Ok so I searched and I could find a bunch of info on oil lights at low rpm but this problem is different.

Background info:
2332, turbocharged, 2-1/2 quart deep sump, oil pickup tube extension installed with no screen, full flow with k&n filter, Gene Berg pump cover with pressure relief feature, 26mm oil pump, 10w30 oil, probably leaving something out so if I did ask. This problem didn't exist until recently when I switched from 20w-50 oil to the 10w-30 and at the same time I also installed the GB oil pump cover with relief valve. The reason for the changes was because I burst the stock doghouse oil cooler on a cold day startup. I also run (and always have with no problems) the oil 1qt low on the dipstick because of the added capacity of the deep sump. I'm also running about 10lbs boost and I drive on the street.

The problem:
When running the engine hard say between 4000-6000 rpm on boost particularly during a hard shift from 1st - 2nd or 2nd - 3rd and then letting off the throttle (also happens when I keep high throttle setting) the engine oil light will come on for 1-2 seconds. This problem occurs if I coast after letting off or if the car is in gear with engine braking. I do not see the light at idle, during hard cornering, during hard braking, etc. The only time I see the light is during hard shifts with the engine on boost. Simple high rpm running will not trigger the light but only when I am like full on boost and bang the gears does the light come on.

My thoughts for someone to critique:
Could this be a cavitation in the oil pump somehow with the lower viscosity oil?
Could the g-force of acceleration be slinging all the oil to the back of the sump away from the pickup tube?
Don't know what else it could be...

I hate to think of all those rotating parts whirling around at 6000 rpm with no bead of oil. I mean dang that sucks, talk about killing some bearings....

Thanks to all who take the time to respond!

Sun Feb 23, 2014 7:28 pm

If the light is on, you ARE starving the bearings of oil, plain and simple. What are you doing for crank case ventilation? If you are venting the valve covers try plugging the vent on the 3/4 cover. Also try running the oil right up to the full line. It definitely sounds like a lack of oil in the sump. On my race engiens I seriously trim back the hat on the oil pickup so that oil drains back into the sump faster

brad

Sun Feb 23, 2014 7:35 pm

slalombuggy wrote: If the light is on, you ARE starving the bearings of oil, plain and simple. What are you doing for crank case ventilation? If you are venting the valve covers try plugging the vent on the 3/4 cover. Also try running the oil right up to the full line. It definitely sounds like a lack of oil in the sump. On my race engiens I seriously trim back the hat on the oil pickup so that oil drains back into the sump faster

brad

I haven't trimmed the "hat" and honestly never really thought of that.
The valve covers are vented 1/2 inch fittings as well as the vent in the oil fill tube which is aftermarket 1/2 inch hose. May I ask why plugging the vent on the 3/4 cover would help? Greater crankcase pressure to help push oil into the pickup?

Sun Feb 23, 2014 7:53 pm

i had the same issue oil ligth on high rpms, both idiot light and gauge, i have a dual pole vdo pressure sender , and a cb performance "in out" 26mm oil pump

first i checked the oil pickup tube , it has a clamp on the extension, it maybe sucked air , fixed that, but issue still the same

then , since i have a T fitting on the pressure port and the oil pressure gauge gets very close to the breast tin, it maybe, under hard acceleration could touch the gauge terminal and get grounded, changed that, still the same issue

finally, changed the oil pump for a cb performance 30mm , and the issue went away..

Sun Feb 23, 2014 8:04 pm

itHaKa wrote: i had the same issue oil ligth on high rpms, both idiot light and gauge, i have a dual pole vdo pressure sender , and a cb performance "in out" 26mm oil pump

first i checked the oil pickup tube , it has a clamp on the extension, it maybe sucked air , fixed that, but issue still the same

then , since i have a T fitting on the pressure port and the oil pressure gauge gets very close to the breast tin, it maybe, under hard acceleration could touch the gauge terminal and get grounded, changed that, still the same issue

finally, changed the oil pump for a cb performance 30mm , and the issue went away..

Well I may try that although I'm hesitant after the major blow out I just had :lol:
But I'd still be curious as to why it only happens under heavy throttle.
I hate problems that are so mysterious like this yet they always seem to happen to my engine.
Glad to see I'm not the only one though...

Sun Feb 23, 2014 8:35 pm

Bobthepilotguy wrote:
Could the g-force of acceleration be slinging all the oil to the back of the sump away from the pickup tube?

Sounds like it.
Gets a gulp of air and takes one or two seconds to re-prime.

Sun Feb 23, 2014 8:56 pm

Have you checked for a loose wire???

You could have the wire touching ground under hard shifts.....I would check the wires or install a gauge to see if it is actually the engine.

Sun Feb 23, 2014 9:04 pm

IMO, our valve covers need no venting as long as our case ventilation is adequate. Fill your oil to the factory height and not one quart low, plug your valve cover vents, vent your case sufficiently, add a drain from the 3/4 side to the sump.

Sun Feb 23, 2014 9:14 pm

It may be that the oil pump is in cavitation. Probably too thick of oil for your set-up. Very serious though!

Sun Feb 23, 2014 9:25 pm

sounds like a little over-revving, that nothing can pick up on, which causes a little cavitation(like a 2-300rpm increase, that your tach isn't picking up, and it probably happens so fast you can't really notice it)

what is you oil pressure hot? maybe its too thin and you want to step up to a 10w40?

Sun Feb 23, 2014 9:46 pm

What happens or what may happen with that strong oil pump and that extra intake tube is it's pulling a vacuum in the intake tube which causes a gap a space where there is no oil. You need a larger pic-up tube or even lighter oil. Probably won't happen with the 10W40 when the oil temp is up to operating temperature of at least 180' f. It should be thin enough then to pick-up. If it does it hot then is likely getting air somewhere.

Mon Feb 24, 2014 1:26 am

How high have you set the pressure on the relief cover? It may be that the motion of the plunger under such a change is slow enough to cause a momentary low pressure, rather than starvation. (think of the valve being pushed towards open, then returning.) I'd still check the pressure switch, too. Can't see trimming the hat making much difference, and trying an ester type full synthetic can rule out foaming. The lower viscosity will actually flow back to the sump quicker.

Hopefully it is just the pressure pulse phenomenon, otherwise you need to go to a dry sump - sorry; stuff like that happens at the bleeding edge of turbocharging.

Mon Feb 24, 2014 1:33 am

Ditch the Berg pressure relief cover and you will most likely be allright. that would be my first move.

T

Mon Feb 24, 2014 1:54 am

I'll buy it off you if it's cheap - they are great in most engines if adjusted right (and a little cleanup done.) The CSP copy is just too danged expensive!

Mon Feb 24, 2014 6:27 am

Bobthepilotguy wrote: slalombuggy wrote: If the light is on, you ARE starving the bearings of oil, plain and simple. What are you doing for crank case ventilation? If you are venting the valve covers try plugging the vent on the 3/4 cover. Also try running the oil right up to the full line. It definitely sounds like a lack of oil in the sump. On my race engiens I seriously trim back the hat on the oil pickup so that oil drains back into the sump faster

brad

I haven't trimmed the "hat" and honestly never really thought of that.
The valve covers are vented 1/2 inch fittings as well as the vent in the oil fill tube which is aftermarket 1/2 inch hose. May I ask why plugging the vent on the 3/4 cover would help? Greater crankcase pressure to help push oil into the pickup?

The 3/4 side is suseptable to filling with oil from the whipping effect of the crank. This will actually pump the top of the head full of oil and start it going up the vent hoses in extreme cases. This means there is less oil in the bottom of the motor to pick up.

I've seen the insides of big time racer's engines that trim the sides of the hat off so there is more room for oil to go back into the sump. Does it work? I don't have any imperical evidence, but I don't see how it can hurt and if it helps get oil back to the pickup faster, that's good enough for me.

brad

Mon Feb 24, 2014 6:30 am

clonebug wrote: Have you checked for a loose wire???

You could have the wire touching ground under hard shifts.....I would check the wires or install a gauge to see if it is actually the engine.

No I haven't checked, given the way the light acts I think it's oil pressure and not a loose wire. The light comes on for 1-2 seconds regardless of g-force on the car. In other words I can be coasting after shifting hard and it will be on during the coast with clutch depressed and then it will go out. Or it will come on during hard acceleration. In any instance the engine has to see peak boost before it will come on. I didn't have this problem until I switched to the berg pump cover and the lighter weight 10w30 oil.

Mon Feb 24, 2014 6:30 am

clonebug wrote: Have you checked for a loose wire???

You could have the wire touching ground under hard shifts.....I would check the wires or install a gauge to see if it is actually the engine.

I might install a gauge but before I do that I could just run a separate temporary wire to a temporary light inside the car with me in the drivers seat. I think I might try that just to be sure.

Mon Feb 24, 2014 6:33 am

bugguy1967 wrote: IMO, our valve covers need no venting as long as our case ventilation is adequate. Fill your oil to the factory height and not one quart low, plug your valve cover vents, vent your case sufficiently, add a drain from the 3/4 side to the sump.

What do the crankcase vent(s) or lack thereof have to do with oil pickup and pressure? I will try the oil level higher. When you say add a drain from the 3/4 side to the sump do you mean from the valve cover via a hose back to the sump? Why, does the oil not drain fast enough through the push rod tubes?

Mon Feb 24, 2014 6:40 am

Quokka42 wrote: How high have you set the pressure on the relief cover? It may be that the motion of the plunger under such a change is slow enough to cause a momentary low pressure, rather than starvation. (think of the valve being pushed towards open, then returning.) I'd still check the pressure switch, too. Can't see trimming the hat making much difference, and trying an ester type full synthetic can rule out foaming. The lower viscosity will actually flow back to the sump quicker.

Hopefully it is just the pressure pulse phenomenon, otherwise you need to go to a dry sump - sorry; stuff like that happens at the bleeding edge of turbocharging.

What is pressure pulse phenomenon? Care to elaborate?
The pressure relief is set (according to berg) at 90-100 psi. I can't see the spring on the pump taking 1-2 seconds to close. I doubt if it even is opening in the first place once the engine is hot. Anyone with a nice gauge and similar setup know what the oil psi is at 6k rpm? I doubt it's reaching 100psi but I could be wrong.

Mon Feb 24, 2014 6:44 am

Try adding more oil first, since you said you're running it below the Full mark... easiest thing to test. Try 1/2 quart (pint) first, then slowly increase...

Simply sounds like temporary oil starvation to me... and you have the crankcase and valve covers vented. So, there's really no downside to running a bit more oil...