Help! Hard coolant pipe won’t go back in

sixmenn

Veteran Member
Joined
Dec 2, 2014
Location
West Michigan
TDI
2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
This is my second time doing this job inside a week. My hard coolant pipe where it inserts into the block under the Injection pump was leaking, so I replaced it. But it leaked again after refilling it, so I removed it to find that the o ring had “rolled”, splitting it down the middle.

I bought a new one and am trying to replace it today, but the same thing looks like it’s going to happen.

The groove that accepts the o ring is approximately the same width as the o ring. But when I try to place the O ring in the groove, it “leans” to one side or the other. So when I try to push the hard pipe back into the block, it gets stuck because the o ring is sitting proud of the hole. Due to space restraints it is impossible to get my fingers in there to help it in. I’m afraid I’m going to end up splitting this one too.

Any advice??? I’ll try to upload pics so you can see what I’m dealing with.

Thanks in advance.

 

csstevej

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2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
To add to the above statement, get some red scotchbrite and clean the hole with it well and try again .
 

sixmenn

Veteran Member
Joined
Dec 2, 2014
Location
West Michigan
TDI
2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission

sixmenn

Veteran Member
Joined
Dec 2, 2014
Location
West Michigan
TDI
2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
To add to the above statement, get some red scotchbrite and clean the hole with it well and try again .
I did clean the hole pretty well the last time I did it (a week ago). It’s impossible to see how good of a job I did though
 

csstevej

Top Post Dawg
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north nj
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2001 golf tdi 4 door auto now a manual, mine, 2000 golf 2 door M/T son's,daughters 98 NB non-TDI 2.0, 2003 TDI NB for next daughter, head repaired and on road,gluten for punishment got another tdi 2001NB,another yellow tdi NB
If I remember correctly there are 2 different types of seals that can be used……I’m not sure if the old smaller one was superseded to the larger one…..
Have you contacted IDPARTS and asked them ? They’ve been very helpful to me when I’ve hard questions about items..
 

KrashDH

Top Post Dawg
Joined
Dec 22, 2013
Location
Washington
TDI
2002 Golf
Here is the new seal sitting beside the original seal. There is definitely a width difference. Do I have the wrong seal perhaps??
There's 2 different o-rings for the hard pipe, see the last reply in my thread:


Judging by what came out of your car, looks like you have the early version and not the latter.
 

P2B

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Toronto & Muskoka, Canada
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There's 2 different o-rings for the hard pipe, see the last reply in my thread:


Judging by what came out of your car, looks like you have the early version and not the latter.
The ID Parts listing says "The early style is a standard style o-ring, where the late style has a molded ridge on it."

The OP's original seal does not look like a standard o-ring to me.
 

KrashDH

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Location
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2002 Golf
The ID Parts listing says "The early style is a standard style o-ring, where the late style has a molded ridge on it."

The OP's original seal does not look like a standard o-ring to me.
Could be, but the new ridged o-ring shouldn't be hanging over the ridges of the groove...maybe someone swapped and forced the new style on previously because it looks pretty cut up? But every o ring groove I've ever seen or designed into tooling/pressure testing has a tolerance that allows the o ring to sit in the groove naturally. None are designed to be "persuaded" into a groove.
 

P2B

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Could be, but the new ridged o-ring shouldn't be hanging over the ridges of the groove...maybe someone swapped and forced the new style on previously because it looks pretty cut up? But every o ring groove I've ever seen or designed into tooling/pressure testing has a tolerance that allows the o ring to sit in the groove naturally. None are designed to be "persuaded" into a groove.
I agree, but the groove in the pipe does not look like it was designed to take a standard o-ring, too wide. It almost looks like the OP was supplied with the correct style but wrong size.
 

sixmenn

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West Michigan
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2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
If I remember correctly there are 2 different types of seals that can be used……I’m not sure if the old smaller one was superseded to the larger one…..
Have you contacted IDPARTS and asked them ? They’ve been very helpful to me when I’ve hard questions about items..
My first seal was from IDParts, and I gave my VIN, so it’s supposed to be the right one
 

sixmenn

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The ID Parts listing says "The early style is a standard style o-ring, where the late style has a molded ridge on it."

The OP's original seal does not look like a standard o-ring to me.
I too read about the two different styles of O ring, and I agree that the groove seems too wide for the “traditional” round type.

the original ring that I removed does have that “double ring groove “ that my new ones have, but it’s only on the inside, not the outside of the o ring.
 

sixmenn

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Have you contacted IDPARTS and asked them ? They’ve been very helpful to me when I’ve hard questions about items..
I just contacted IDParts and Josh got back to me right away. He didn’t have any solutions for me, other than to suggest I use petroleum jelly to insert it (which I dismissed due to the probability of degradation of the rubber).
Some questions for the forum:

1. Would two traditional seals side by side in the groove be a solution?
2. Is there a tool available that would compress the o ring while I insert the hard coolant pipe? Could this be accomplished with a hose clamp, perhaps??
3. Is it possible that a previous owner installed a different engine or hard coolant pipe that takes a different o ring?
 

KrashDH

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Dec 22, 2013
Location
Washington
TDI
2002 Golf
1. For this, you still need the right sized seal. O-rings seal based on the tolerances of the groove depth, ID and OD of the o-ring, and ID of the bore. Failure to meet any of these specified tolerances will result in an improper seal.
2. If the o ring is oversized, you run the risk of "pushing" material and causing a hump in the o ring...which may seal on the outside but if you move that material outwards there's potential of leaking on the inside of the o ring. Not to mention you run the risk of rolling or pinching it. The compression of the o ring is based on material, ID and OD and the tolerances.
3. Always a possibility.

Moral: you need to figure out the proper o ring to use. You can use red rubber grease, vaseline, silicone grease to lube the o ring. Heck, a bit of coolant also. If you look in my thread, the o ring that came out looks similar to the o ring that went in. Yours that came out doesn't look like the one you got. Something is off.

Did you send those images to ID parts?
 

BobnOH

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I'll be that guy what posts the stupid comment, but what holds that fitting in place?
 

P2B

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I'll be that guy what posts the stupid comment, but what holds that fitting in place?
The pipe is bolted to the block.

 

jmodge

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I believe there are two different hardpipes. The early one will not accept the double o-ring. If it isn't something you are doing wrong, try the other o-ring.
I just measured the groove for the double o-ring, .250 wide. How wide is yours.
 

sixmenn

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Dec 2, 2014
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West Michigan
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2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
IDParts got back to me and asked for my VIN to confirm I had received the correct o ring. I thought it was pointless because I had given them the VIN when I ordered the part.
Sure enough, he ran the VIN and my car shows it takes the other O Ring. I have it on order and it’ll be here Tuesday. Crazy thing is that both IDParts and my local dealership sold me the wrong O ring, supposedly based on the vin

Hopefully I have good news on Tuesday afternoon when i tackle this again.
 

gmenounos

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For future reference, here are some part numbers for the hard pipe and their corresponding O-rings. You could look at the part number of your pipe and figure out the proper O-ring from that if you don't have the ability to look up by VIN.

For manual transmission:
Original '98-99 pipe: 038-121-065-A that uses old-style O-ring (WHT-006-407)
Newer (but now discontinued pipe): 038-121-065-AM that uses new-style O-ring (06B-121-687)
Newest pipe: 038-121-065-Q that uses new-style O-ring (06B-121-687)

https://forums.tdiclub.com/index.ph...tdi-mkiv-a4-w-alh-engine.513522/#post-5646696
 

sixmenn

Veteran Member
Joined
Dec 2, 2014
Location
West Michigan
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2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
For future reference, here are some part numbers for the hard pipe and their corresponding O-rings. You could look at the part number of your pipe and figure out the proper O-ring from that if you don't have the ability to look up by VIN.

For manual transmission:
Original '98-99 pipe: 038-121-065-A that uses old-style O-ring (WHT-006-407)
Newer (but now discontinued pipe): 038-121-065-AM that uses new-style O-ring (06B-121-687)
Newest pipe: 038-121-065-Q that uses new-style O-ring (06B-121-687)

https://forums.tdiclub.com/index.ph...tdi-mkiv-a4-w-alh-engine.513522/#post-5646696
Is the part number stamped somewhere on the hard coolant pipe?
 

sixmenn

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Dec 2, 2014
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2001 VW Jetta TDI manual transmission , 2000 VW Jetta GLS TDI manual transmission
Just wanted to follow up: I received the other coolant hard pipe o ring and installed it. It was certainly narrower than the groove on the hard pipe, which made me concerned that it wasn’t going to be right either. But it installed way easier, and as far as I can tell I have no leaks.
Thanks again to all for the help!
 

KrashDH

Top Post Dawg
Joined
Dec 22, 2013
Location
Washington
TDI
2002 Golf
Just wanted to follow up: I received the other coolant hard pipe o ring and installed it. It was certainly narrower than the groove on the hard pipe, which made me concerned that it wasn’t going to be right either. But it installed way easier, and as far as I can tell I have no leaks.
Thanks again to all for the help!
That width isn't a huge deal. The minor diameter of the groove is more important as well as the bore the pipe goes into. The sealing is between the bore surface and o ring interference. So the width of the groove isn't really a concern. Under pressure the o ring will basically "roll" to the outer groove wall and wedge itself in there by design
 

PakProtector

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Mk.4's and the Cummins
If you examine the 'industry standards' on o-ring grooves, a longer slot specified; usually around 30% longer than its cross section.

Douglas
 

jimbote

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spiral arm, milky way (aka central NC)
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What I've found over the years is if the pipe also bolts to the coolant flange stud is uses the o-ring. If it only bolts to the block it uses the X ring. There may be exceptions but I haven't encountered them yet.
 
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