ALH leaking vacuum pump

runonbeer

Maintenance EnthusiastVendor
Joined
Apr 15, 2002
Location
Austin, TX/Chapel Hill, NC
TDI
'00 Golf 02M, '10 Golf 02E, '02 UTE 02M
He replaced the o-ring because they get hard and crispy and start leaking. It's kinda the entire basis of this thread.
 

Rembrant

Veteran Member
Joined
Oct 31, 2014
Location
Canada's Ocean Playground
TDI
2013 Golf TDI DSG
He replaced the o-ring because they get hard and crispy and start leaking. It's kinda the entire basis of this thread.
Oh...my bad then for not paying full attention...lol. I thought the basis of the thread was the loose/leaking nipple on the vacuum pump.

I see now that the original discussion was on the case o-ring.

Carry on...don't mind me.
 

boertje

Veteran Member
Joined
May 24, 2002
Location
Coeur d'Alene, ID
TDI
'01, '01, '03, ‘06 NB - TDIs all.
Is that local to you? if it holds fine I'd love to order a few or try to find some locally.
Keep us posted.
No, it's a few hours drive to the south of me.
Just out of curiosity, why did you need to reseal the pump? Did it start leaking or did you take the pump apart for some other reason?
mrrhtuner...you should be able to buy them locally without any trouble. I may grab a couple myself for the VW spare parts bin...as soon as I find out why they're needed. If they fail at some point, then fine, I might as well have 'em.
Yup, leaking pretty bad. Nipple was loose too so I took care of that at the same time.
Nobody around me locally has that particular size. Even o-ring store had to order them as they were out of stock. What I liked is no minimum order.
He replaced the o-ring because they get hard and crispy and start leaking. It's kinda the entire basis of this thread.
Exactly.
 

mrrhtuner

Veteran Member
Joined
Mar 29, 2011
Location
London Ont Canada
TDI
2003 Jetta Wagon TDI, 2015 Passat TDI, 2015 Touareg TDI
Just out of curiosity, why did you need to reseal the pump? Did it start leaking or did you take the pump apart for some other reason?
mrrhtuner...you should be able to buy them locally without any trouble. I may grab a couple myself for the VW spare parts bin...as soon as I find out why they're needed. If they fail at some point, then fine, I might as well have 'em.

I'm asking as the vacuum pump that came on my 03 wagon, the previous owner(s) must have loved gasket maker. It was on the oil drain plug (stripped threads) and on the vacuum pump, which I suspect is leaking.

I'd want to give 'er a good clean and a new o-ring and beat the nipple a bit lol

:D
 

climbtheplanet

Well-known member
Joined
Aug 22, 2008
Location
Boulder, CO
TDI
2001 Golf
Has anyone purchased multiples of the 74 x 2.5 v75 vitron o-ring that would be willing to sell me a single? Or has anyone found a supplier of those single o-rings? I have found lots of 100 but would rather kick a few bucks for one or two from someone who has already bought a box of them.
 
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climbtheplanet

Well-known member
Joined
Aug 22, 2008
Location
Boulder, CO
TDI
2001 Golf
Runonbeer, would you be willing to drop one of the 74x2.5 o-rings in an envelope and send one to me? I will gladly pay for the stamp and a few bucks for the part. I did finally find singles at theoringstore.com of the Buna-N in 74x2.5 and V75 in 71x2.5 and 77x2.5, but if you have a source for the "just right" 74x2.5 vitron that would be awesome.

An After Though:

I just found the temp ratings of different o-ring materials here, http://www.theoringstore.com/index.php?main_page=page&id=6 , and discovered Viton -10 to 400F vs Buna-N -30 to 250F. Living in Colorado, I'm wondering if the Buna-N compound would actually be a better fit because I think it is unlikely that with it's placement the vacuum pump would reach 250F, but we definitely got colder than -10 here this last winter, and my car definitely sat without running in those temps for a couple days.

Thoughts?
 
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climbtheplanet

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Joined
Aug 22, 2008
Location
Boulder, CO
TDI
2001 Golf

boertje

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Joined
May 24, 2002
Location
Coeur d'Alene, ID
TDI
'01, '01, '03, ‘06 NB - TDIs all.
I had that question as well. Runonbeer recommended to me the v75 Viton one since it had higher temp capability.
 

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
Fortunately for me, the dealer in Reno had one in stock so it is waiting for me at the parts counter. I had him double check the VAG number 071115444.
I have a spare vac pump body to put the o-ring into to see if I can get more than 11" it is currently willing to pump. I will keep you all posted.
 

boertje

Veteran Member
Joined
May 24, 2002
Location
Coeur d'Alene, ID
TDI
'01, '01, '03, ‘06 NB - TDIs all.
Just had a car come in with 14" Hg. Swedged the nipple so it was tight again and replaced the o-ring. Results: no leaks and 25" Hg.
 

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
Seven weeks later the BRM o-ring is still working great, 25" of vacuum when tested yesterday. I also used the tap-tap method on the end of the nipple
 

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
As a heads up, my rebuilt vacuum pump is still pulling 25" of vacuum.
The way to test with your Mity-Vac is to take the vac line that goes to the top of the N75 valve past the check valve and parallel to the "vacuum bulb" and see what you get at idle. If you get 24-25" of vacuum you are in good shape; if you don't disconnect everything except the N75 valve and eliminate the problems one by one as you head towards the passenger side of the engine compartment. I had two bad solenoids that are now disconnected caused me a huge loss in vacuum.
 

boertje

Veteran Member
Joined
May 24, 2002
Location
Coeur d'Alene, ID
TDI
'01, '01, '03, ‘06 NB - TDIs all.
Anyone?
I'd like to pull my vacuum pump and replace the seals and clean up the oil leak.
OD will be fine. That's what I used. You might have to stretch it just a little bit though. Going on 15k miles and leak free.
I did buy an oil filter (wix) for the brm. Gasket lasted 100 miles and then started leaking.
 

03TDICommuter

Veteran Member
Joined
Dec 8, 2016
Location
So. Cal
TDI
01' NB, 5spd
OD will be fine. That's what I used. You might have to stretch it just a little bit though. Going on 15k miles and leak free.
I did buy an oil filter (wix) for the brm. Gasket lasted 100 miles and then started leaking.
So you started with the brm oil filter o-ring and later used a 74mm OD Viton?
 

03TDICommuter

Veteran Member
Joined
Dec 8, 2016
Location
So. Cal
TDI
01' NB, 5spd
Yup, the brm gasket that came with the wix filter swelled up almost immediately causing leak again. The Viton o-ring I used is this. http://www.theoringstore.com/index.php?main_page=product_info&cPath=368_65_67&products_id=41003
See this post. http://forums.tdiclub.com/showpost.php?p=5069065&postcount=97
So far it's working perfectly.
Thanks! I'm going to go ahead and get the McMaster Viton one. We order so much from them at work that I can tack on my o-ring for essentially 'free shipping'.
 

mrseadog

Active member
Joined
Mar 8, 2015
Location
St. Louis, MO
TDI
2002 Jetta
According to above posts in this thread the correct oring size is 74mm ID x 2.5mm CS. http://www.theoringstore.com/index.php?main_page=product_info&cPath=368_65_67&products_id=41003

A suitable alternative may also be AS568 Size 150. These are 2-7/8"ID X 3-1/16"OD X 3/32"CS (Metric: 72.69mm ID X 2.62mm CS) which is pretty close to the metric one http://www.theoringstore.com/index.php?main_page=product_info&cPath=367_79_83&products_id=3574

The cost for the AS568 Size 150 is $1.00 ea while the metric is over $7.00 ea.

I ordered several and will try them out when they come in.
 
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Solamia

Well-known member
Joined
May 26, 2010
Location
Kansas
TDI
2001 Blue Jetta TDI (380K mi)
The oring store is where I got my 2.5mm X 74mm just right size. The part number is V2.50X074. It is V75 Viton O-ring Black. If it's not listed on their web site, call them. That's what I did.
BTW, as per http://www.theoringstore.com/index.php?main_page=index&cPath=368_65, Operating temperature: -20° to +400F°

Did this o-ring continue to be leak free? I'm about to order from the O-ring store myself and wanted to know if you would change the dimensions any for a better seal IF the one you put in hasn't stayed leak free. Thanks for any update you can give!
 

Solamia

Well-known member
Joined
May 26, 2010
Location
Kansas
TDI
2001 Blue Jetta TDI (380K mi)
According to above posts in this thread the correct oring size is 74mm ID x 2.5mm CS. http://www.theoringstore.com/index.php?main_page=product_info&cPath=368_65_67&products_id=41003

A suitable alternative may also be AS568 Size 150. These are 2-7/8"ID X 3-1/16"OD X 3/32"CS (Metric: 72.69mm ID X 2.62mm CS) which is pretty close to the metric one http://www.theoringstore.com/index.php?main_page=product_info&cPath=367_79_83&products_id=3574

The cost for the AS568 Size 150 is $1.00 ea while the metric is over $7.00 ea.

I ordered several and will try them out when they come in.
How has the alternative size o-ring worked out? Staying leak free? I'm
about to order for my vacuum pump and am curious how the two sizes listed in this thread are working out. Thanks for any update you can give!
 

Nevada_TDI

Top Post Dawg
Joined
Aug 17, 2008
Location
Reno, sort of...
TDI
2001 Jetta TDI
I realize the one from the dealership is quite expensive compared to the "generic", but mine has been in for at least a year and there has been no problems with it.
 

Solamia

Well-known member
Joined
May 26, 2010
Location
Kansas
TDI
2001 Blue Jetta TDI (380K mi)
I realize the one from the dealership is quite expensive compared to the "generic", but mine has been in for at least a year and there has been no problems with it.

I see from above posts that you used the brm oil filter ring. Thanks for your feedback!
 

boertje

Veteran Member
Joined
May 24, 2002
Location
Coeur d'Alene, ID
TDI
'01, '01, '03, ‘06 NB - TDIs all.
Did this o-ring continue to be leak free? I'm about to order from the O-ring store myself and wanted to know if you would change the dimensions any for a better seal IF the one you put in hasn't stayed leak free. Thanks for any update you can give!
Yes, this o-ring is still doing the job. I have a spare and will use it with confidence.
 

BakoTDI

Veteran Member
Joined
May 5, 2005
Location
Bakersfield, CA
TDI
Jetta, MK7
So, after reading this entire thread, has anyone encountered loss of vacuum from having a leaky seal, or were you experiencing vacuum loss from the loose nipple? or both?
I checked my pump today and for sure, the nipple is loose. I attached my vacuum pump to the end of the EGR valve hose (will this still be accurate?) and got about 15" and after wiggling the loose nipple, I do see it fluctuate between 15 and 20". I also checked for any possible oil leaks from the head/pump seal and it seems like previous owner did some work on it because I can see some oily film on the back corner of the head cover. Couldn't tell you when that developed or if it's even from the vacuum/head seal, but will have to keep an eye on it after wiping it clean. After all the trouble everyone seems to be having with resealing the pump, I'm not sure I even want to take it off! haha

Anyway, today I came across this video on youtube (https://www.youtube.com/watch?v=7aRX4gfcpek) and was wondering if anyone had come across this before, and since nobody mentioned it, I thought I would share it. The website the kit can be bought is this (https://www.rkxtech.com/products/vw-alh-tdi-vacuum-pump-reseal-kit). Some of you seem to have purchased the 2.5mmx74mm V75 Viton from the O-ring Store and seem to have no problems with it. I am thinking that if this is the right o-ring size, I might not have to get the kit I mentioned above since there are no specifications on the size of the o-ring included in the kit.

Finally, did anyone experience any issues replacing the head/pump seal? Not the round one but the oddly shaped one.

Ok, one more thing: since we the vacuum is also related to the brake booster, could this be the reason why my brakes, from time to time will make this weird noise when you slow down at low speeds, and feel some strange vibration on the brake pedal? It makes a sound kinda like a small compressor running for a few seconds...If I let release the brake pedal and press again, it goes away and brakes work normally. It happens very quickly and not every time. On average once a week, but sometimes two or three times that day. Anyway, maybe the loose nipple issue fixes both my low vacuum and my weird brake issue.
 
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