'72 Bus - Oil Pressure Low

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Sluggo
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'72 Bus - Oil Pressure Low

Post by Sluggo » Sun Dec 03, 2006 12:25 pm

I've mentioned my oil pressure problems before but I'll summarize.

Had low oil pressure before the rebuild. Did a complete rebuild but still have low oil pressure once warm. I've used 2 different used Type 4 pumps and still have the same exact pressure. Two days ago I pulled the Relief Valve, Plug & Spring from a spare case. The Valve was a slightly different shape, the spring was shorter and the plug was deeper on the spare. My plug has a bevel on the lower ledge of the groove (the spare has no bevel. just a groove). The spare plug is just slightly deeper and has a VW logo (mine has a wierd design). The pare spring is about 1 inch shorter than mine. My spring is very difficult to compress and get screwed in (sticks out about 1 inch before compressed into the hole). It shoots out when you remove the plug. The spare fits perfectly.

With the new valve & plug (old longer spring) my oil pressure increased just slightly. But still barely comes on once warm and goes out with the slightest tap of the pedal.

Should I try the smaller spring form the spare? Or is there something else I can do.

Before anyone asks. Bearings are new and clearance is perfect. No leak at the sender. Slight oil leak between 3/4 head & cylinders.

I tried to put in 30mm Schadek but the lower shaft boss just barely hits the cam bolts. They were clearanced for the Type 4 Pump but apparently this is not enough for ther Schadek. Is there a way to clearance the pump and not the cam bolts? I'd hate to split the case just to grind down a couple of bolts. Especially if this might not even fix the problem.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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Amskeptic
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Re: '72 Bus - Oil Pressure Low

Post by Amskeptic » Sun Dec 03, 2006 6:48 pm

Sluggo wrote: Had low oil pressure before the rebuild.
With the new valve & plug (old longer spring) my oil pressure increased just slightly.
Should I try the smaller spring form the spare?
No leak at the sender.
Like a certain other poster has endured, I am going to bear down hard on getting answers to specific questions, so we can cleanly diagnose.

Do you have a factory sender or an aftermarket sender?
Aftermarket senders typically turn on the idiot light at 10 psi on down.
The factory sender turns on the light at between 6 and 2(!) psi.

Answer this and I will then help you understand that the pressure relief valve has nothing to do with low oil pressure at hot idle :colors:
Colin

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Sluggo
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Re: '72 Bus - Oil Pressure Low

Post by Sluggo » Sun Dec 03, 2006 6:50 pm

Amskeptic wrote:
Sluggo wrote: Had low oil pressure before the rebuild.
With the new valve & plug (old longer spring) my oil pressure increased just slightly.
Should I try the smaller spring form the spare?
No leak at the sender.
Like a certain other poster has endured, I am going to bear down hard on getting answers to specific questions, so we can cleanly diagnose.

Do you have a factory sender or an aftermarket sender?
Aftermarket senders typically turn on the idiot light at 10 psi on down.
The factory sender turns on the light at between 6 and 2(!) psi.

Answer this and I will then help you understand that the pressure relief valve has nothing to do with low oil pressure at hot idle :colors:
Colin
Stock idiot light sender and VDO Dual Post for the gauge.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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Sluggo
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Post by Sluggo » Sun Dec 03, 2006 7:00 pm

I just found a site that says if you have a Type 4 Bus case with the fuel pump boss drilled out, you shouldn't tap the gallery plug by the fuel pump. You'll eliminate the brass push rod guide and it will drop your pressure.

http://www.danallum.com/aircooled/case_prep.htm

I didn't do this, but someone did. Because I have that gallery tapped and plugged. So I guess I need the brass push rod sleeve. Now I need to figure out where to find one.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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Amskeptic
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Post by Amskeptic » Sun Dec 03, 2006 7:41 pm

Sluggo wrote: I have that gallery tapped and plugged.
So I guess I need the brass push rod sleeve.
We went through all of this with your engine on theSamba last year. Remember? Ratwell got all sniffy on me when I said a missing fuel pump pushrod would dump oil out the end of the gallery? He said, no way excuse me they have sleeves that meter the oil coming from the end of the gallery.

This discussion was, I thought, one of the main reasons you decided to tear the engine down in the first place, low oil pressure that you could not explain.

Now your engine is back up and you have been around the bush a thousand times and the oil pressure is low still and the fuel pump pushrod/gallery issue is still a mystery? :pale:

Danallum is dead wrong dead wrong dead wrong when it comes to the right lifter gallery plug. That's the one that fell out on my engine.
Would he say, "too bad for you"? I get so irritated. . . .
This is not rocket science. If you have a secure but shallow threaded plug, you do need to see if the brass sleeve is visible. If it is, then you can guess that it is metering the oil more slowly than a sleeveless, pushrodless hole. I would fill the hole with a pushrod cut down to avoid your block-off plate by about .040" at maximum lift of the cam eccentric and let the pushrod slow the oil still further. I am surprised this is an unresolved issue.

I was going to say, keep the pressure relief valve/spring/piston nice and stock, a stronger spring could rupture the oil cooler on a very cold morning. It is not your "adjustable oil pressure regulator." Read my section on lubrication, it is on your computer. Look for "oil control valve" Read it. It is your total pressure control. If the plunger is sticking down in the "dump" position, it mirrors the lack of a brass sleeve/pushrod and it happens to dump the oil pressure off the same gallery between the lifters for cylinder #1. Remove the splined cap and you will have the exact spring piston deal as the relief valve at the left rear end of the case. You sure don't want to be screwing up and crossing springs and pistons between the two. Did you and Bottomend clean both of these oil relief/control bores at overhaul time?
Colin

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Post by Sluggo » Sun Dec 03, 2006 7:59 pm

Amskeptic wrote:
Sluggo wrote: I have that gallery tapped and plugged.
So I guess I need the brass push rod sleeve.
We went through all of this with your engine on theSamba last year. Remember? Ratwell got all sniffy on me when I said a missing fuel pump pushrod would dump oil out the end of the gallery? He said, no way excuse me they have sleeves that meter the oil coming from the end of the gallery.

This discussion was, I thought, one of the main reasons you decided to tear the engine down in the first place, low oil pressure that you could not explain.

Now your engine is back up and you have been around the bush a thousand times and the oil pressure is low still and the fuel pump pushrod/gallery issue is still a mystery? :pale:
I knew you were going to say that. You did tell me to put the pushrod in place and make it a bit shorter. But I had an image of the cam lobe slapping the rod into the block off plate and causing trouble. Also, when I tried the pushrod out it was very sloppy in the bore. I looked inside and didn't see any type of sleeve. This is another part of why I didn't do it. Then I just kind of spaced it. So I have no sleeve.
Danallum is dead wrong dead wrong dead wrong when it comes to the right lifter gallery plug. That's the one that fell out on my engine.
Would he say, "too bad for you"? I get so irritated. . . .
This is not rocket science. If you have a secure but shallow threaded plug, you do need to see if the brass sleeve is visible. If it is, then you can guess that it is metering the oil more slowly than a sleeveless, pushrodless hole. I would fill the hole with a pushrod cut down to avoid your block-off plate by about .040" at maximum lift of the cam eccentric and let the pushrod slow the oil still further. I am surprised this is an unresolved issue.

I was going to say, keep the pressure relief valve/spring/piston nice and stock, a stronger spring could rupture the oil cooler on a very cold morning. It is not your "adjustable oil pressure regulator." Read my section on lubrication, it is on your computer. Look for "oil control valve" Read it. It is your total pressure control. If the plunger is sticking down in the "dump" position, it mirrors the lack of a brass sleeve/pushrod and it happens to dump the oil pressure off the same gallery between the lifters for cylinder #1. Remove the splined cap and you will have the exact spring piston deal as the relief valve at the left rear end of the case. You sure don't want to be screwing up and crossing springs and pistons between the two. Did you and Bottomend clean both of these oil relief/control bores at overhaul time?
Colin
I cleaned every last orifice of that case. I cleaned it incredibly well. Bottomend confirmed my job.

I look for the write up and read it. I've read a few of them. I've got to crack down on myself.

I'm looking around. Where can I get a sleeve?
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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chitwnvw
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Post by chitwnvw » Sun Dec 03, 2006 9:30 pm

I would think that the only danger of adding that galley plug would be taking out a cross section of that sleeve. Wouldn't the plug then block that passage and you wouldn't have any return. I thing it would be pretty easy to check this.

Here's a pic of my sleeve, from the other (cam) end, but the sleeve is pretty pronounced.
Image

My gut reaction is you're on the wrong track. There's just not that much oil traveling through there, isn't it just enough to lube that pushrod and the fuel pump. I'd get rid of that splitter and try a different sender. Scott as GS supposedly has a better crop. I'm going to order one, I'll order two if you want and send one your way.

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Post by Sluggo » Sun Dec 03, 2006 10:25 pm

chitwnvw wrote:I would think that the only danger of adding that galley plug would be taking out a cross section of that sleeve. Wouldn't the plug then block that passage and you wouldn't have any return. I thing it would be pretty easy to check this.

Here's a pic of my sleeve, from the other (cam) end, but the sleeve is pretty pronounced.
Image
I have no sleeve. It's just not there. The PO must have removed it (or GEX). I have had Colin, that website and Piledriver (who's opinion I also respect a lot) tell me this. Finding the site jogged my memory and when I mentioned it on STF Piledriver said that it really effect oil pressure. Colin also agrees here. Plus I have done 2 different oil pumps, 2 relief valves, and confirmed the integrity of the relief bore. Tried 2 stock senders, The VDO 2 Post and a mechanical gauge. All of them read very low (5 PSI or less) once warm.
My gut reaction is you're on the wrong track. There's just not that much oil traveling through there, isn't it just enough to lube that pushrod and the fuel pump.
It's gotta be it. Everything else has been covered. And Colin suggested this in the first place a year ago. Now I just keep getting it confirmed.
I'd get rid of that splitter and try a different sender. Scott as GS supposedly has a better crop. I'm going to order one, I'll order two if you want and send one your way.
Thanks but I'll pass on the sender. I have a few. Plus they can't all be wrong.

It can't hurt to try replacing the sleeve/pushrod. Then I'll know it's covered.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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Sluggo
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Post by Sluggo » Mon Dec 04, 2006 2:42 pm

Just pulled the Fuel Pump Block Off Plate from my engine. Slid a pushrod in there and confirmed that there is no bushing. Checked a spare case I have and there is a bushing. The bushing is a pretty tight fit around the pushrod. The bushing covers the end of the lifter gallery (I think). And without it, oil pours out of the gallery to the case. Basically an internal oil leak.

Placed a shortened Fuel Pump Pushrod in there and sealed it up. Pressure did increase slightly. But still not what it should be.

Hopefully I can find a fix for this that doesn't involve splitting the case.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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chitwnvw
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Post by chitwnvw » Mon Dec 04, 2006 3:25 pm

How long did you make your pushrod? I've got the rod, just want a safe length...

Is that sleeve the same size as the valve guides? I seem to recall, but memory fuzzy...

Why don't you get the inside diameter of that hole, and take that and the pushrod to a machine shop. You'll get a sleeve that you can press in...

Orrrrr, what about getting a bigger rod that fills up that hole better...

Orrr what about jb welding your hole and then leaving a pin hole for a little bit of drainage...

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Sluggo
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Post by Sluggo » Mon Dec 04, 2006 6:27 pm

chitwnvw wrote:How long did you make your pushrod? I've got the rod, just want a safe length...
Not sure. I just put it in and cut off 1/4 inch more than what stuck out. And verified that it wouldn't get jammed by turning the crank.
Is that sleeve the same size as the valve guides? I seem to recall, but memory fuzzy...
Could be. Not sure. Looks about the same.
Why don't you get the inside diameter of that hole, and take that and the pushrod to a machine shop. You'll get a sleeve that you can press in...

Orrrrr, what about getting a bigger rod that fills up that hole better...
Piledriver suggested this at the STF.
Piledriver wrote:Put a large, long setscrew THROUGH the plug (tap plug) and have it seal the hole, I can't remember if it's coaxial though, probably is. (red) locktite setscrew to seal.

Would require engine pull, flywheel come off, pull/drill/tap plug (and make sure things will line up) NO need to split case.
I kind of like your idea better. I'm gonna ask around and get some more opinions.
Orrr what about jb welding your hole and then leaving a pin hole for a little bit of drainage...
Taken out of context, that paints a disturbing picture.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

User avatar
Sluggo
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Location: Portland, Or.
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Post by Sluggo » Mon Dec 04, 2006 6:45 pm

Amskeptic wrote:Read my section on lubrication, it is on your computer. Look for "oil control valve" Read it. It is your total pressure control. If the plunger is sticking down in the "dump" position, it mirrors the lack of a brass sleeve/pushrod and it happens to dump the oil pressure off the same gallery between the lifters for cylinder #1.
Just read your write up. Good amount of info. Explains the whole lubrication system. You should do a similar write up for the Tech section.
:vwgauge420:

1977 Bus with Sunroof - "Lucky '77"
2000cc Type IV w/Dual Weber 36s,
Aircooled.net SVDA w/Compufire,
Redline Weber Fuel Pump,
Holley Regulator,
Half Ass Brush & Roller Rustoleum Paint Job,
Incomplete Custom Interior,
Dual Batteries,
Crunched Slider Door.
------------------------------------------------------

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chitwnvw
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Post by chitwnvw » Mon Dec 04, 2006 9:59 pm

Sluggo wrote:
Orrr what about jb welding your hole and then leaving a pin hole for a little bit of drainage...
Taken out of context, that paints a disturbing picture.
Yikes! I meant on your engine. Don't do it....

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Amskeptic
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Post by Amskeptic » Mon Dec 04, 2006 10:22 pm

Sluggo wrote:
Orrr what about jb welding your hole and then leaving a pin hole for a little bit of drainage...
Taken out of context, that paints a disturbing picture.
LOL Sluggo, if you kept your gallery plug in place and just found a rod with a slight interference fit in the pushrod hole and tapped it in almost to the camshaft, it will not go anywhere and it will seal up your gallery nicely. No muss, no fuss, nice and quick job. Just measure it to be shorter than the distance between the block-off flange and the camshaft eccentric tap it on down and put the block off plate back on.
Colin

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chitwnvw
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Post by chitwnvw » Mon Dec 04, 2006 10:35 pm

Is it ok to seal it off entirely? Or does there need to be some dribbling toward the camshaft....

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