Belgian1979vette

I have a question about the canton 15-240T RR pan.

Did any of you ever fill up the pan with 6,7 quarts and see where the level ended up in respect to the baffle in the pan ?

I was advised to fill the pan with 7 quarts by the tech rep from Canton and then adjust the dipstick.

thanks

ggrassmid

PMARTINEZ92126

I think i have the same pan on my 86 automatic. I filled it with 7 quarts. I had the machine shop adjust the dipstick. All is well so far.

Aardwolf

Yes I have. When I got mine I filled it with water to study flow control and amount of fill needed. Six quarts filled it to the bottom of the baffle. I run extra when I track the car. I think total fill is around eight quarts for track use, less for street. When I did the water study the pan controlled fluid poorly to the front, such as under braking. Turn five at Road America proved this well when oil pressure would drop to four PSI. I need to fix the pan yet or get a better one.

Belgian1979vette

Strange, Canton in their mail to me said specifically it had a content of 7 qrts.

Was the pan on the correct inclination when filled ?

Belgian1979vette

I'm not. I'm seeing a drop off in oil pressure on high rpm.

1991Z07

I had the same issue...turns out there was a problem with the oil returning from the heads back to the pan at high RPM's.

To fix it, we smoothed the valley and inside the heads so the oil flowed easier. The machinist also opened up the return holes a bit to speed things up.

I run a Ron Davis radiator with integrated oil cooler (an automatic style radiator) and run my oil through it. My OEM oil/water cooler was not that great. With that, I run 8 quarts in my system. Never have had any issues with pressure drops since then...but my next addition will be an AccuSump system...probably a 2 quart version. It's cheap insurance if you run the car hard around corners.

Belgian1979vette

A couple of things. I did some testing before. As I took off the valve covers to check valve lash after a hard hot run, there never was too much oil under the covers. The block drains were matched to the heads, so this at least could be ruled out.

Yesterday I changed to a new filter and took power off from the accusump. This cured the problem. Running the power to the accusump, made it return but less pronounced.
What this leads me to believe is that both the filter and an overfilled pan have something to do with it.

The filling of the accusump is dependant on pressure which is dependant on oil temp. What happens is that when the oil is cold and at startup with cold pressures the accusump gets filled to it's maximum. If you correct the oil level to the full mark, you will get an overfilled pan because when warm the oil pressures are lower making the accusump dumps some of its oil in the pan.

1991Z07

Well, to be fair, by the time you got the covers off the oil had long drained back to the pan...

Did you adjust your dipstick full setting? I did it when I first filled the engine...filled the oil filter from one of the 7 quarts, installed it and then filled the pan with the rest.

That sets it pretty accurately.

Belgian1979vette

Not sure about that. When a filter is dry is sucks in more oil because it needs to get the paper element filled (you should try that), meaning that actual amount of oil contained in a wet filter is less...

project C4

http://forums.corvetteforum.com/c4-t...l-picture.html

Belgian1979vette

Well, after a lot of mails from and to Canton, they now say that 7qrts is system capacity with about 1 qrt ending up in the filter in stock position. This would leave about 6 qrts in the pan itself. So it seems I got overfilled with about a qrt which could explain the pressure drop experienced over 5000 rpm due to windage/aereation.

I'm going to refill and adjust the dipstick to 6 qrts.

1991Z07

Hmmm...I think I explained that above in my previous post.

Take 7 quarts of oil...fill the oil filter from 1 quart. Pour the remainder from that plus the other 6 quarts into the engine. Allow to "settle" for about 10 minutes, then insert dipstick. Full level should show on the stick...mark and scribe that line on the dipstick.

Belgian1979vette

unfortunatly 6qrts in the pan resolved nothing as to the dropping pressure at rpm.

1991Z07

The next question is how far off the pan is the pickup for the pump?

And...do you have an AccuSump? Because if not...I would. Good insurance...not fool proof, but better than nothing...short of a dry-sump system.

Belgian1979vette

Yes accusump is in the system. Pickup is between around 1/2" from the bottom as per instructions from Melling.

I did some further testing. It seems to be oil pump cavitation, although I have the special anti-cav feature in the pump. I'm going to try a different oil weight and synthetic. Just filled her up with 5W30 syn. I specifically measured 6qrts and put in the pan to see where it ended up. It was about half way between the full and add mark where I set it with 7qrts in the system. Kinda odd. Tomorrow I intend on warming her up at low rpm, then get the oil pressure up to the 60 psi I'm usually seeing before the drop off and then measure how much oil is still in the pan and add untill she's back at the level of 6qrts. That should keep the pickup more than covered. Then a run over 5000 to see it solved anything.

If it doesn't I think I'll have to pull the pan and look into the pump. A dry sump would be a great solution, but I run a C3 and there is virtually no room for the pump and the oiltank.

Belgian1979vette

Meantime I performed a test with a lighter weight synthetic oil (5W30) and although I'm still experiencing some pressure drop (5 lbs where it previously was 15-20 psi) it's a lot less and more importantly it doesn't drop further. Also, idle oil pressure was up 10 psi

1991Z07

That's interesting...50W is too thick for your clearances and is dropping the pressure?

I have no choice...if I want the oil pressures to stay where I'm comfortable, I HAVE to use 50W. I'm in Texas...and right now air temps are in the low 100's...which means they are in the 130's-140's coming off the pavement. When I ran 40W...it turned to water and my pressure tanked...even with a VERY good oil cooler.

Once I converted my OEM oil/water cooler over to a Ron Davis radiator (with cooler for an automatic)...my oil temps rarely get above 200 degrees. Only on extended runs did I see them climb to 210-215, and my pressures stayed stable at 65 PSI. As a bonus...when temperatures are cold, the oil temps get stabilized pretty quickly as the radiator brings them up to water temperature fast.

5 PSI is a lot better than 15-20 PSI...but it still shouldn't be dropping like that. Something is still affecting it...and at this stage I can only think it's the oil pump. My machinist opened my brand new Melling and completely reworked it...smoothing everything and making the clearances exactly what he wanted. I don't know what kind of black magic he worked in there...and he's died since then so I'd need a medium to contact him to ask.

All I know is it gives me 75 PSI cold, and 65 PSI hot...and it's solid as a rock.

I understand your dilemma on the dry-sump...I'm working on a '92 ZR1 body for a track car, and intending to put an LS7 in it. Packaging and routing the dry-sump will be an adventure. I can see it already...

In a C3 with the closer confines of the engine bay...and having to lean over fenders to work on it, my back is already hurting thinking about it.

Belgian1979vette

I think I've run into oil pump cavitation. 50W is a very heavy oil to run in your car. Shouldn't be like that especially with oil temps in the 200 range I would think.

I think the oil cavitation is brought on by the oil bypassin too much due to the HV pump. It heats up too much (I also saw oil pressure drop with the lighter weight) and causes cavitation. Maybe the engine also exhibits a windage problem.

Some suggest using a std pump, but when doing the oil change and completly emptying the accusump I noticed the oil pressure was low when it refilled even with the HV pump.

I'm going to try and stay away from the dry sump as much as I can ,but if it turns out to be a windage problem then I won't have much choice I presume.

1991Z07

I'm running the high volume pump as well...

Maybe increase the spring pressure on the bypass valve? If not...what type of filter (with built in bypass) are you using?

A Wix is set to bypass at 8-11 psi differential while an AC Delco is set at 11-17 psi.

I've used the Mobile 1 truck filter on mine since the engine build nearly 40k miles ago...double the filter media of the OEM size and 2x the dirt holding capacity of other brands. It uses a synthetic filter media...

Just another thing to look at...don't know if it will apply to you, but the filter can affect the pressure as well.