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Wed Jun 25, 2008 2:06 pm

Alright one more question on this. My oil pressure light/buzzer is fine starting, driving, even on the highway cruising at 65. But when I get off the highway at my exit, as I pull up to the stop sign, it starts blinking and buzzing. I shut it off, start it again, no problems the rest of the way home. Is the oil just sloshing to the front and not getting pumped or what??? It's filled to about 2/3's of the way to the top mark on the dipstick, 20W50 (with a little Marvel Mystery Oil to quiet a lifter).

Wed Jun 25, 2008 2:45 pm

When you get off of the highway, your oil is about as hot as it gets and, consequently, it is also as thin as it gets. Just shutting it off for a minute or so is long enough for the oil to cool a bit and gain enough viscosity to keep the warning system from, well, warning you again.

I'm guessing that the oil pressure is, in fact, marginal. Fortunately, wbx's don't need that much oil pressure to survive. The end may be getting close for yours, though. And it is worth more as a rebuildable core without the additional crancase ventilation.

I suggest you install a gauge, and watch it closely when your light and buzzer are going off. Then, go back to the first page of this thread and very carefully read tencent's excellent essay dated Aug 29, 2007 about oil pressure problems. It's all there.

You could install a new CB Performance oil pump, shim the relief valve spring, and install an oil cooler. All those things would help, and the engine may run another 50,000 miles. Or it may chuck a rod tomorrow. The sad fact is your oil pressure is low because your engine is worn.

How many miles does it have?

Wed Jun 25, 2008 7:18 pm

195k... Looks like the heads were replaced at least. They say AMC I think, I need to take the air cleaner off again to see. I saw an insignia while I was cleaning everything. Also, I realized that the exit has a pretty good right hand bend also, so tonight I took it a little slower and it didn't come on. I'm going to go ahead and get the gauge kit so I don't have to keep wondering.

Wed Jun 25, 2008 7:20 pm

FYI - this is my first real experience with the WBX, my other's were all 2 liters... Thanks again for the tips.

Thu Jun 26, 2008 12:17 am

riceye wrote:

I'm guessing that the oil pressure is, in fact, marginal. Fortunately, wbx's don't need that much oil pressure to survive. The end may be getting close for yours, though. And it is worth more as a rebuildable core without the additional crancase ventilation.

I suggest you install a gauge, and watch it closely when your light and buzzer are going off. Then, go back to the first page of this thread and very carefully read tencent's excellent essay dated Aug 29, 2007 about oil pressure problems. It's all there.

You could install a new CB Performance oil pump, shim the relief valve spring, and install an oil cooler. All those things would help, and the engine may run another 50,000 miles. Or it may chuck a rod tomorrow. The sad fact is your oil pressure is low because your engine is worn.

How many miles does it have?
I agree with everything you say EXCEPT about shimming the relief valve spring. That will do nothing to remedy low oil pressure. The relief valve only comes into play at the high end of the range. During the low pressure occurances the relief valve is completely closed. How tightly closed is irrelevant.
Al

Thu Jun 26, 2008 6:55 am

Quote: I agree with everything you say EXCEPT about shimming the relief valve spring. That will do nothing to remedy low oil pressure.

Theoretically, true. In practice, ehhhh, not so much. A 1.5mm thick shim under the relief valve will raise hot OP a few psi under load, as much or more than a high-volume oil pump does in the same motor and conditions. The boost varies with temp and rpm, and is very little at idle so it may not be enough to keep the oil warning at bay. I've done controlled tests of both remedies.

Thu Jun 26, 2008 11:32 am

Okay, good to know. I'll try it myself on a borderline one. Simple enough to do it. what do you use for a 1.5mm shim?
Al

Thu Jun 26, 2008 1:00 pm

A common 1/4" washer. It should fit over the small boss on top of the relief valve plug so it stays centered. Stamped steel washers like that are made from 1/16" stock, which is about 0.065" thick.

Tue Jul 01, 2008 11:49 am

simd0ggie wrote: ...now waiting to see if I have a head gasket leak, It does not seem as if I do... Thanks again!

Wait 'till the outside temperature drops below freezing. :(

Fri Jul 04, 2008 7:51 am

Okay, Tescent, can you tell me how to get the oil pressure relief valve off? A screwdriver isn't going to do it, and thought I better ask before I start hitting it with a hammer.

Fri Jul 04, 2008 8:33 am

Yeah, they're just about the stoopidest thing I've ever seen, those plugs. Why the F it's a flathead slot and not an in-hex or whatever is beyond me. I keep swearing I'm going to start welding hex-nuts onto those plugs. I'm starting another rebuild today and I might just make good on my word. There are alternative plugs available for T1's, but surprise surprise, in VW's infinite wisdom, the wbx case uses a much larger plug, so no alternatives exist that I know of.

Anyway, you're wise to not go hammering on it and ask for some advice first, because once you mess up that all-too-shallow slot you are completely screwed, pun not intended. There's no rim on the thing to speak of that you could put a vice-grip on, so once the slot is boogered up, it's weld or drill, take your pick. I've seen many that were chewed to unrecognizability by someone chiseling on the rim, and I doubt they ever got them out anyway.

I use one of those handheld impact drivers that come with a few screw tips, one of which is pretty fat and a decent fit for the slot. Then one or two sharp blows with a BMFSH on the impact driver usually knocks it loose.

Another method which has always worked, because the BMFSH works great if you can flip the car on its roof but not so great under the car where you have like a whole 8 inches of room to swing the hammer upward, is to get your biggest flat screw driver, raise the car an inch with a jack, and build up wood blocks under the screwdriver handle until it's wedged in place engaged with the screw. Then lower the car onto the screwdriver. It helps to drill a wide hole in he top woodblock so the butt of the handle has a place to rest. Or if you have a floor jack, use it to hold the driver handle in the slot. With the weight of the car pushing down on it, the driver tip will stay engaged in the slot, while you wrench the handle with a visegrip. Or if you have those fancy Snap-on drivers like I keep breaking that has a hex on the shank, a regular spanner will do. That's the King-Kong approach but it's always worked as a last resort.

Fri Jul 04, 2008 9:05 am

Got it off, drilled out the center of a washer to fit the boss, installed. Took a test drive, buzzer still comes on after it's good and hot (65 with AC for about 15 mi.) and I slow down to exit the highway. Right when I hit about 2200rpm, obviously because I'm at the low end of the high pressure switch range... I'll have to start saving for the 'better' wbx I guess.

Fri Jul 04, 2008 10:07 am

simd0ggie wrote: Got it off, drilled out the center of a washer to fit the boss, installed. Took a test drive, buzzer still comes on after it's good and hot (65 with AC for about 15 mi.) and I slow down to exit the highway. Right when I hit about 2200rpm, obviously because I'm at the low end of the high pressure switch range... I'll have to start saving for the 'better' wbx I guess.
Next time you go shopping, get 4 or 5 quarts of Shell or other quality brand 40 weight oil. not multi- viscosity anything. Multi-vis is not nearly as good as straight weight for maintaining oil pressure. (Well, maybe Mobil 1 15-50)
Never run the oil level over full. 1/2 quart low is what I aim for.
Sure, your bearings are getting a little worn. My 91 was that way at 110k miles. It now has 160kmiles and I've been in 22 states since then. It still seems to have about the oil pressure.
Also, I recently have been trying to drive a little slower, mostly to save gas, but I'm sure the oil is cooler, too. I usually do not exceed 65-70mph
Al

Fri Jul 04, 2008 10:13 am

Quote: Also, I recently have been trying to drive a little slower, mostly to save gas, but I'm sure the oil is cooler, too. I usually do not exceed 65-70mph
Al

This seems about right. I have an oil pressure gauge and my oil pressure drops a bit if I drive a while above 70mph. Under 70 it's stable. I seem to remember Dogpilot posting about this topic too. I think he monitored oil pressure and temperature and found that above 4K RPM's, which is approximately 70 mph, is where oil temp starts to spike and oil pressure drops. Not a big deal in a new fresh engine on a cool day, but with worn bearings in the heat of the summer it will set off the alarm.

Fri Jul 04, 2008 7:34 pm

Yeah, it really seems like it's the revs that heats up the oil more than any other factor. Keeping the revs lower on an older engine is a good strategery.

Sun Jul 06, 2008 8:14 pm

I was getting low oil pressure at sustained highway speeds (65mph) on a relatively warm day. With ~250k on the engine there were few band aids to throw at a warn main bearing.

So... I now have a new engine.

Tue Jul 08, 2008 4:55 am

markz2004 wrote: I was getting low oil pressure at sustained highway speeds (65mph) on a relatively warm day. With ~250k on the engine there were few band aids to throw at a warn main bearing.

So... I now have a new engine.
I find it truly amazing that it was not giving you trouble at 175K miles. Look s to me like you cheated death for 75K miles.
BTW, it is not necessary to shut off the engine to get the buzzer to quit. Just push in the clutch and gun the throttle to get the engine speed up a little to get the oil pressure up a little. this will shut off the buzzer and if the motor immediately drops to below 2000 rpm before the oil pressure drops, the buzzer will stay off. It will stay off until the rpm once gets over 2000rpm and it sees the oil pressure switch has not closed.
But if you are coming up to speed on a freeway, it is a moot point because the rpms will be much higher and so will the oil pressure. so if it buzzes at all, it will stop very soon.
And if that doesn't do it, better head back home and put in the straight weight 40w oil like I told you yesterday. Or just park it till the new engine comes.
Al

Tue Jul 15, 2008 12:46 pm

I have a rebuilt engine in my 86GL, just over 1500 miles on it and for the last 600 or so the oil buzzer comes on briefly when I am in 4th ger and slow down to about 2200 to 2500 RPM. Or if I shift early from 3rd to 4th without running 3rd all the way up to 4000 rpm. Pushing the clutch in and reving the motor a little usually shuts off the buzzer, but it will come back until the rpms rise or I shift to netrual and let the engine idle. Also if I keep the pedal down and get the RPMs up it goes away. This also happens very occasionly when slowing down in 3rd gear. This is always after the motor is warmed up, and yes I am using a Mahn filter and 20-50w oil.

I did have to replace the water pump at about 500 miles and the oil buzzer was going off all the time, but that was because the wire to the sensor had been tucked out of the way of the belts and not plugged in. My mechanic did check the oil pressure and he said it was good at 45psi.

Do I need a new sensor?

Thu Jul 17, 2008 10:20 am

Okay Tencent, I got my gauge and sender kit from Van-Cafe. It took a while but I got it in. I'm reading 45 psi at idle, going up over 70 as I rev it up. Isn't that high???

Thu Jul 17, 2008 11:51 am

Your oil pressure will be that high when the engine/oil is cold. The real test is to get your engine nice and hot and then look at the oil pressure. Search for common oil pressure levels. Others should chime in with specifics based on more experience then I have but, you should be getting at least 10lbs at a hot idle and 30lbs at a hot highway speed (65mph). These two measurements are at the low end of a healthy range.