Water Leak On 1.6

[G727 0]

Hello all,

 

After replacing the head gasket on my 1990 1.6 I have now developed a coolant leak from the back of the engine. I have located where it is leaking - it's from the rear head bolt at the front (cyl. no. 1) of the engine.

 

It would appear that the head bolt goes into a waterway...is this correct or has somebody forgotten to put the spacer in place and have cut a thread through into a water way previous to me owning it?

 

Any advice is appreciated.

[Anthony 1,003]

There should be two spacers on the headbolt nearest the cambelt, exhaust side - one thick, one normal.

 

If you miss out the thick spacer as many people do, then you punch the headbolt straight into the waterpump housing causing the leak.

[Atari Boy 11]

One of the head bolts needs an extra large spacer, I can't recall exactly which one from memory.

I am sure someone else will confirm exactly which one it is however.

[G727 0]

Guys, many thanks for the quick reply!

 

It would appear that that is exactly what mine has had done to it, as there was a sealing residue around the bolt.

 

Probably a bit of a stupid question, but is there a fix for this? Or is it new block time?

[Tom Fenton 1,541]

New block is an ideal world fix, but otherwise people have success with epoxy metal type stuff.

[G727 0]

hmm, OK. I suppose the cooling system is not under that much pressure so a liquid metal type repair would do the trick.

 

Many thanks for your advice.

[G727 0]

Just a thought, as a temporary repair just so I don't keep leaving a little pool of coolant everywhere would a radiator sealant work?

 

Although saying that I am slightly concerned about reports that Radweld etc. cause heat spots

[Anthony 1,003]

I would think that the resultant hole would be too large to successfully fix with radweld or similar, not to mention the other potential issues with adding that stuff to the cooling system.

 

I've used chemical metal in the past to repair exactly this problem, and it held and worked fine for thousands of miles until the car was eventually scrapped (for unconnected reasons). Just drain the coolant, clean up the area around the hole, and apply the chemical metal to the area. Following day once it has dried, you should be able to fill it with coolant and have no further issues.

[G727 0]

Cheers Anthony, Your last post has at least given me some confidence that it will be a permanent fix.

 

I shall give it a go this weekend.

 

Kind Regards,

Sam.

[Tom Fenton 1,541]

The main thing to try and get a good result is getting the area nice and clean, use brake cleaner or similar to remove any oil etc.

[ken707 0]

Hi folks, I'm opening up this old topic for some more advice.

 

I've got one of the rare 1.9 GTI automatics which needed the valve stems replaced.

 

I've now got a water leak from the bottom of the rear head stud nearest the water pump. I fitted the large spacer onto this head stud but see that it still protrudes through the block, same as the others.....I didn't notice when refitting, should there be a short stud as well in this position?

 

I replaced the water pump at the same time so will pull it out tomorrow to have a look inside the housing.

 

I happen to have bought some JB Weld recently, would this be ok to use for a repair?

 

Any help would be appreciated.

 

Ken

[welshpug 1,657]

did you use a washer as well as the large spacer?

[Anthony 1,003]

As above, there should be both a small and large spacer on that rear cambelt-end headbolt above the waterpump, with just a small spacer on the other nine bolts. Miss either and the block gets damaged.

 

The headbolts themselves are all the same.

 

JB Weld should be fine for repair if you have holed the block, the important thing is ensuring that it's properly cleaned and degreased first prior to attempting repair.

[ken707 0]

did you use a washer as well as the large spacer?

Yes, the smaller washer is also in place on the head, all checked today. Access is awkward but I've taken a couple of pics, top and bottom. I've measured the spacers, seem about 30mm, but where the stud protrudes through the block it looks exactly like the other studs, no sign of damage to the block. I just can't understand what I've done wrong unless there should be another spacer which I've missed.

 

I've been told to unscrew the stud and use threadlock or similar. That might be the best solution but I'm a bit reluctant as the head studs were difficult enough to remove originally. Alternatively should I add another 10/15mm spacer and seal the block as discussed. Advices please?

 

If you want to pm email addresses to me I can send pics. Very many thanks so far.

[welshpug 1,657]

if the spacer and washer are present than its probably a rotten gasket.

[dcc 855]

There should be 2 spacers abovr the water pump, 1 large and 1 small, sound like you have missed one. People saying washer is a bit misleading, some headbolts come with washers which arent removable, but in addition to these you need 1 large and 1 small spacer above the waterpump. All other headbolts should have 1 small spacer

[ken707 0]

There should be 2 spacers abovr the water pump, 1 large and 1 small, sound like you have missed one. People saying washer is a bit misleading, some headbolts come with washers which arent removable, but in addition to these you need 1 large and 1 small spacer above the waterpump. All other headbolts should have 1 small spacer

 

That's what's confusing me, I work in a clean area and have no parts or washers left over. The spacers are approx 30mm, I'll need another 8/10mm to leave enough room to plug the hole at the bottom, I certainly should have noticed notice a spacer like that.....unless it's fallen down the front of the engine!

 

Anyway, thanks for the help.

[steve@cornwall 100]

It's always possible that the damage was done on a previous repair, the correct parts fitted and then some epoxy metal filler used with the bolt in place. Once you remove the bolt the repair is disturbed and the leak returns.Ive bought a couple of engines/cars repaired this way in the past.

[ken707 0]

It's always possible that the damage was done on a previous repair, the correct parts fitted and then some epoxy metal filler used with the bolt in place. Once you remove the bolt the repair is disturbed and the leak returns.Ive bought a couple of engines/cars repaired this way in the past.

 

This area is so difficult to see, I had thought the advice was that the head bolt shouldn't protrude at the bottom as the others do. I now see how the damage can occur and, yes, I am guilty. In fact the spacer had fallen down onto the chassis leg and initially I didn't know where it came from.

 

When I was cleaning the threads I ran up against resistance on that bolt and backed off. I then realised what the spacer was for. Luckily I hadn't gone too far and now that I'm looking in the right place, can see the damage is slight.

 

Good design should have make it impossible to remove the spacers for that one stud.

[dcc 855]

I believe the later 16v xu heads are machined to not need the additional spacer!