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Posted by: lmcchesney Apr 20 2004, 05:52 PM

I read some where regarding the loss of oil pressure in high G turns that the case can be over filled to accomidate additional oil volume. The tuna can adds about 1/2 qt below the sump. Is it possible to over fill the case to the point that you do not let the sump go dry with the turns? What is the down side? Is there a volume where you have high oil pressure problems?
Thanks,
L. MCChesney

Posted by: ! Apr 20 2004, 06:03 PM

The case doesn't go dry....the oil just sloshes over to the corner and evades the pickup. The tuna can provides enough for most turns. At least I have yet to hear of anyone over running one.

If you have concerns that YOU might...consider a deep sump that the offroaders use or an accusump pre oiler.

Posted by: lmcchesney Apr 20 2004, 06:58 PM

Mike,
It's toooo low for a deep sump. Tuna can is on. But thinking about this, when the G force is applied you must get a diagonal displacement. Therefore, the higher the oil level, the higher the portion remaining over the sump.
L. MCChesney

By the way, did I see that you had a 1.7L rebuilt longblock for sale. I was thinking about the new member, loveporsche, who is a high school guy wanting to rebuild/replace his engine with a $1500 budget. He's on the site.

Posted by: Dave_Darling Apr 20 2004, 06:59 PM

I have managed to get the oil light to come on even with the tuna can. I went "ramping" one day, doing all four ramps of a clover-leaf. I think it was on the fifth ramp in a row, the light came on toward the end. More than good enough for me!!

You cannot fill up the engine to the point where the pickup will never be exposed. Not without making the cam and possibly the crank sit down in oil, which will rob much of your power and heat the oil up like a mother.

You can, however, overfill the 914 engine slightly, and that is supposed to help a little bit without running into any real issues. Fill it about as far above the "fill" line on the dipstick as the "empty" line on the dipstick is below it. This should put you about a half-quart over, which is about all you want to try.

An Accusump will provide oil pressure for longer, but IMHO it isn't needed unless you get paranoid about scraping the Tuna Can. (E.g., if your engine is at the very back of the car like in a Bug or a 912.)

--DD

Posted by: lmcchesney Apr 20 2004, 07:03 PM

Thanks Dave,
Since my engine is going back together, I should mark the dip stick at the level of the pick up below the crank? That way I will have a real reading.
L. Mcchesney

Posted by: Dave_Darling Apr 21 2004, 02:16 PM

I'm not sure I understand your question...

If you are asking if you should put a mark on the dipstick below the two current ones.... Uhh, NO! That would result in you under-filling the engine with oil, which is a Bad Thing.

If you're asking if you should put a mark on the dipstick above the current ones... I'd say no. Just remember you want the thing over-full by a little bit, but don't lose the easy reference to where "full" is.

--DD

Posted by: lmcchesney Apr 22 2004, 09:40 AM

No Dave, I would not identify a site producing less oil volume.
Look at the attached 1/2 case. Where are the "oil pickups" and thus where is the maximim level. Instead of estimating the measurment by about as far above fill as empty, could you not identify the max line on the open case and place the dip stick and mark the max on the dip stick. Silly question?
L McChesney


Attached image(s)

Posted by: Dave_Darling Apr 22 2004, 11:18 AM

Heh... Toldja I didn't understand what you were saying.

There is one oil pickup. It isn't in the pic, but it is just above the half-circle cutout in the middle of the bottom, there.

If you look below the cam in that pic, you'll see a channel cast into the case. That's where the "windage tray" goes. The idea behind it is to keep the oil, which should almost all be in the sump below it, from getting whipped up into the rest of the case by the moving air coming off of the crank.

How far below the windage tray should the oil level be? I don't know. When the oil sloshes around, it could get over the tray and take some time to get back down again. Or it could get picked up by the air moving around in there. (Robs you of power, heats up the oil...)

If you're looking for some absolute "here is where the oil should be", I don't have it for you. I figure the VW engineers probably had some reasonable idea what they were doing when they figured out how much oil to put in the motor, so I use the stock dipstick. Though they didn't necessarily know that we were gonna put wide sticky tires on the car and take it around long sweeping corners at high rates of speed. So then I trust the experience of those who came before me, who say "put in a half-quart over full".

Between that and the tuna can, I have no problems in any reasonable situations.

As with some of your previous questions, I think you're really over-thinking this. Use the tuna can or an accusump, put in an extra half-quart, and be happy. Don't worry about any of it unless you see the oil light come on.

--DD

Posted by: lmcchesney Apr 22 2004, 11:24 AM

Yelp! That helps. Thanks again.
L. McChesney

Posted by: Tom Perso Apr 22 2004, 01:22 PM

Posted by: vsg914 Apr 22 2004, 01:31 PM

Not to hijack this thread(this is kinda related), but I gotta dipstick question. I've got three 2L motors, and a 1.7 that I was comparing the dipsticks. The 1.7 has a tube that sticks up about three inches above the oil filler. Two of the 2L's have a tube about the same height of the filler with equal length dipsticks. The third 2L has no tube and a short stick that goes all the way to the top of the case. What's up with that?

Posted by: lmcchesney Apr 22 2004, 03:32 PM

I'm sorry. I tried. I even passed the post by but came back.
(tounge in cheek) vsg914, that really is a dipstick question.

Yeah, the 1.7L extends about 3-4 inches out of the dip stick tube. I do not know where the deep end of the stick lies.