ALH leaking vacuum pump

[mannytranny]

I've had an annoying oil leak from my vacuum pump for quite a while now. I bought a new seal for the part that mates the pump to the head but that didn't fix it. I yanked it and put some FIPG along with the seal, still no luck. But this time I saw that it was actually leaking at the next seal over which separates the two pieces of the vacuum pump itself.

So I removed the pump and took apart the three torx bits tat hold the two parts of the pump together. Voila, another oil seal. This is the one that is leaking. So, new Toyota FIPG and reseal. I see no reason why this wouldn't fix the problem.

So, just in case anyone else is wondering why their vacuum pump leaks oil (which also may appear to be a head gasket, rear main or valve cover gasket), there is a secondary seal that may very well be the issue.

Happy TDIing!

 

[runonbeer]

90% of ALH cars that I see have some degree of oil leak at this location.

What is "Toyota FIPG"?

I believe that LUK manufactures these pumps (as well as the tandem PD pumps). I just spent about 10minutes trying to find contact info for LUK to inquire about the possible availability of this seal and was not successful.
Anybody else wanna give it a shot? I'm not exactly a whiz at googling for corporate info on my iPhone. I think Jim from dieselgeek already made an inquiry about the internal PD tandem pump seals and they told him to take a hike.

 

[jcrews]

Vacuum pumps are safety-relevant components in the vehicle. For this reason, it is not possible to repair the vacuum pump. Before assembling the vacuum pump and drive (on the engine side), check for wear. Carefully clean the sealing flange on the engine and the vacuum pump. The seal should always be replaced.

Weak.

http://www.lukclutch.com/content.sc...iathek/library/library-details.jsp?id=3346449

The pumps are mfd by LUK, part of the Schaeffler group.

Toyota FIPG is just the form in place gasket (RTV) sealant.

 

[mannytranny]

Ya...the Form In Place Gasket works great...I just put in the original O ring and then add the FIPG around the gasket. I just can't see any reason to throw away the whole pump when it is leaking just because of an old o ring.

 

[runonbeer]

So they make great DMFlywheels and lousy, leaky vacuum pumps.

Guess I'll go down and fill up the inside of my vac pump with RTV today.

 

[runonbeer]

UPDATE: see posts 12 & 13 for correct part to use

Ok, I just had a F**K YEAH! moment. Hanging at my shop waiting for my GF's plane to land since my shop is close to the airport.

I am doing a motor swap on this golf so I pulled the vacuum pump apart since he's getting a new (used) one with the motor he just bought.

First of all, this one was not leaking appreciably



so I took it off and took it apart. There are 3 T-30s that have to come out to split the pump in half:



Using a screwdriver to pop it apart after the bolts are out (I know, these pics are overkill):



Turns out, this seal is a simple o-ring, formed to the shape of the vac pump body. Here is a pic of me holding up an old ALH oil filter o-ring I keep in the box to hold the lower charge pipe to the sway bar end link while doing a timing belt change, next to the seal I removed from the pump:



as you can see, they are essentially the same total diameter seal and the next pic demonstrates that this used piece of trash o-ring fits quite perfectly into the boss in the vacuum pump body:



That one shows the "new" seal pressed into the boss in the pump body with the old seal sitting dejectedly aside.
The "new" seal is actually of a bit thicker cross-sectional diameter which should theoretically provide a better seal.
I should also assume that it will easily last 10,000 miles (the frequency at which these used seals are generated) before it leaks again.

I hope that everyone finds this information as useful as I do.

Now I can actually fix this leak instead of having to appologize for the car.

 

[mannytranny]

Ya...I thought about that oil seal but didn't have one handy and figured the fipg would take care of it.

Score!

FWIW, mine looks good, fipg holding.

 

[ymz]

I knew there was a reason why I kept a bunch of my used oil filter "O" rings...

Nice going,

Yuri

 

[runonbeer]

can't wait to get my hands on a PD tandem pump...

 

[runonbeer]

I knew there was a reason why I kept a bunch of my used oil filter "O" rings...

Nice going,

Yuri

There are now two reasons

 

[aNUT]

can't wait to get my hands on a PD tandem pump...

...just ask jim for the one I sent him. The seals are smaller, shaped, and not simple buna rubber...so best of luck. If you can find a solution, you'd keep a lot of fuel from drooling out of these pumps onto the ground as well as drastically improve starting perfromance after the car sits for a couple days. The only recourse at this point is to replace the complete pump, which lists for over $300 IIRC.

 

[runonbeer]

Bump.

It's actually some brands of ALH oil filter orings that are too thick. BRM filter O-rings are just the right thickness.

 

[runonbeer]

O-ring is 74mm x 3mm

 

[vankei]

While on the topic of vac pump leaks, has anyone had the nipple come loose creating a leak?
Thanks

 

[runonbeer]

Yes they have. I'm working on that. For now, just slather some JBweld on it.

 

[vankei]

Figured as much, but thanks for the heads up. Sounds like a job for the morning.

 

[josh8loop]

I did a big no-no today. Insead of using this great resource, I plowed ahead and did it my way. Shame on me!!!

I am having an annoying vacuum pump gasket leak that I thought was coming from the "P" shaped gasket. I have replaced two of these on this car, and have always had an oil seepage there. Frusterated about the leak the last time I used some Ultra Grey RTV on the vac pump to head gasket. I went sparingly on the RTV and ended up having the leak come back but seemingly worse this time. Long ago I had disassembled the vac pump and had seen that other gasket between the two halves, and not having a replacement gasket for it, I put some RTV on it too. Now that my leak is back, I once again removed the two vacuum pump sections, cleaned the area and applied some fresh RTV to it. I wish I would have seen this information in this thread before I applied the RTV again. I guess in the future I will use my old ALH oil filter O ring and replace that vac pump gasket with it instead. I may have to look at work to see if I have a spare large viton O ring to replace it with next time. Thanks for the valuable information on this fix guys!

 

[josh8loop]

I am positive that even if I use an old O ring from the oil filter housing that has 10K on it, that once it is installed into the vacuum pump and undisturbed that it should have a very long life correct? Any updates from anyone as to the longevity of this fix(although it looks like a perfect solution )?

 

[runonbeer]

The ALH ring is too thick. You'll have to get a BRM ring or equivalent 74x3mm

 

[josh8loop]

The ALH ring is too thick. You'll have to get a BRM ring or equivalent 74x3mm

Thanks for the clarification on the ALH oil filter O ring being too thick!

Question


Looks like I can get a viton O ring that is 75x3mm- will that most likely work?

They also have a Buna N "O" ring that is 74x3, but I would prefer the Viton if at all possible.

 

[runonbeer]

I don't know. never tried a 75.

 

[josh8loop]

Ok, thanks for the info. I went ahead and ordered the Buna N 74x3mm "O" rings like you suggested. The Buna N will be perfect for the temperatures involved and the engine oil. I think they come 25 per pack, but they are relatively inexpensive. Looks like I'll have plenty to give for gifts to my local TDI friends here After I'm through none of us will have vacuum pump oil leaks again!

 

[josh8loop]

Just replaced it last night, and took some DIY photos. So far so good, but it's too early to call it a success though. The last time I had it apart(a week ago) I took out that seal and coated it with Ultra Grey RTV since I didn't have a replacement at that time. I figured, what the heck, I may as well try something! Well, as it turns out, certain parts of the vacuum pump have a slight bit of oil pressure, and the RTV didn't stand a chance. It only took a few days for me to start notice it leaking again, so in a few more days I will be able to know whether or not it was a success or not.

Sure glad I found the info here on the replacement "O" ring. It fit perfectly with a slight bit of stretching before I formed it into place. So I can confirm, the 74x3mm was perfect as RunOnBeer suggested. I will post in a week or so as to the results. I fully expect that they will be positive

 

[josh8loop]

Well, It's been a while with the new McMaster Carr purchased 74x3mm O ring that I installed on the vacuum pump. It still leaks on me! I've been trying to get this issue fixed for the last year and a half or so. In fact, ever since I got the car at 105K miles it was leaking. I inspected the new O ring I put in there for any damamge that I could have done during the installation. No damage was found, but I did notice the O ring seemed a bit thin relative to the O ring land area and it definately molded into a square shape over the short amount of time it was installed. I measured the new O rings I purchased from McMaster, and they measure 2.85mm thick instead of the 3mm they are suposed to be. Must be 3mm nominal thickness I guess.

I'm not 100% sure where the oil is coming from, but from what I can tell it seems to be coming from between the two halves of the vac pump. I figured I would use some 1500 grit wet or dry sandpaper and clean up the vac pump body sealing surfaces between the two halves and look for any high spots that may be giving me trouble. I put the sandpaper on the granite kitchen countertop so I got a very flat end result. I probably removed .001-.002 of material. Doing this step should at least remove that from the leak equation. So far my list of possible leak points are:

Valve Cover(that is UltraGrey RTVed on)
Undersized(2.85mm thick) replacement vac pump body O ring
Slight step between the cam bearing cap and the aluminum head


We will have to wait and see if this latest effort was successful. I would definately recommend folks who replace the vac pump body O ring make sure they get a full 3mm thick O ring-It does make a difference!

 

[josh8loop]

I ended up finding a 75x3.4mm O ring from work that is Viton. If the work I did last night doesn't work, then ill try this one. It looks a little thick however.

 

[runonbeer]

Make sure the pump rotates by hand with the thicker seal installed before you put it on the engine.

 

[josh8loop]

Well, unfortunately the work I did the other night with the new O ring, and lightly sanding down the sealing surfaces didn't work-It's still seeping a bit of oil already. Eventually I will try the thicker Viton O ring and see what happens. Thanks RunOnBeer for the advice about making sure it turns by hand with the new thicker O ring installed-I will make sure I do that. I'll keep yall posted on progress!

 

[ymz]

Hope your work isn't in vane...

Does anyone have a VW part number for a BRM oil filter "O" ring?

Yuri

 

[JetPuf]

Hope your work isn't in vane...

Does anyone have a VW part number for a BRM oil filter "O" ring?

Yuri

OE Part number is 071115444

 

[_MattMan]

Great Thread !! Thanks everyone for the helpful tips and " RunOnBeer" for great pictures & instructions. After Growler & I replaced my engine earlier this year, we noticed a small leak. After several attempts to figure it out, including using another vac pump, Growler found this thread.

Well, last night I took my pump off, followed the helpful tips from this tread and installed a BRM filter O-ring in place of the " Flatten " O-ring.

Replacement O-ring fits like it belonged there and appeared to have enough to properly seal it up.

Too early to tell but I have my fingers crossed this works as we have been scratching our heads for some time now trying to pin this one down.

I took pictures and will add any that may help upon review, one thing I noticed on my pump which I didn't catch until I had did the rebuild and had installed it back on my car was the vac hose connection on the pump was very loose and turned. The loaner Growler provided me didn't so I decided to take it off, rebuild Growlers and installed it.

Time will tell, stay tuned and again thanks for all the tips everyone, great support, makes one feel proud to be part of a great club. Hope to meet some of you at TDI Fest.