Just finished a front end rebuild (first 2 photos and third - all buttoned up) but I just noticed a small leak above the water pump (fourth photo). I've never seen one leak right there before. What's everyone's impressions?
Leaking coolant
- Thread starter Buddysuede
- Start date
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- Thread starter
- #2
Oops, sorry about the second photo...don't know how that beer got in there!
I remember seeing a thread where a guy had a leak in the same areas.. its probably a o-ring.. of course you'd have to get someone to chime in on part #'s etc.
Would have to track down if its dripping from above in that photo or from right where the photo shows it etc
Would have to track down if its dripping from above in that photo or from right where the photo shows it etc
- Thread starter
- #4
Thanks Timer00. Anybody else think it's just an o ring?
I don't, sorry. I had a leak in this exact area. I replaced the o-ring, really polished the aluminum elbow and tried a fatter o-ring and the leak persisted. The culprit turned out to be the gasket between the thermostat housing and the timing cover. Since I never removed the housing, I never replaced the gasket, but loosening the nuts on the pipe to install the thermostat caused my gasket to leak in the exact area you have in that picture. The only difference is that my leak was red and not green. I believe the gasket part number to be 16119-66020. It can be replaced with everything in place and only a gallon of coolant needs to be drained. Replacing it 5K miles ago kept the area bone dry.
Good luck.
Good luck.
- Thread starter
- #6
Thanks so much on the input. I'll let everyone know if that's the problem after replace the gasket. Thanks Aim
- Thread starter
- #7
I did just replace the radiator, all coolant hoses and fan and rebuilt the fan clutch. I guess something in that process screwed up that gasket.?!
I added a couple of arrows to your picture to point out the the gasket in question. In my case, removing the nuts that hold the thermostat in place loosened the housing and started the leak (what I call the housing is the part towards the USPS side of the gasket, left in your picture), since the only thing holding the housing in place at that point are the studs going through it and, I think, a single bolt.
If you did NOT replace the thermostat, the gasket is probably not the problem and the 3 o-rings* that go with the nipple and pipe arrangement (to the right in your picture) would be my next guess. I live in the North East and the road salt caused a fair amount of corrosion on the inside of the aluminum pipe. If you start messing with it, be careful, since the nipple that is inside the pipe seals against the timing cover.
* there is an o-ring at the top of the pipe where it joins the head, and two o-rings at the nipple that joins the bottom of the pipe to the timing cover/water pump housing. The o-rings, nipple and pipe aren't that expensive; if you decide you want to replace yours, I have a brand new set I bought in desperation before I replaced the gasket.
If you did NOT replace the thermostat, the gasket is probably not the problem and the 3 o-rings* that go with the nipple and pipe arrangement (to the right in your picture) would be my next guess. I live in the North East and the road salt caused a fair amount of corrosion on the inside of the aluminum pipe. If you start messing with it, be careful, since the nipple that is inside the pipe seals against the timing cover.
* there is an o-ring at the top of the pipe where it joins the head, and two o-rings at the nipple that joins the bottom of the pipe to the timing cover/water pump housing. The o-rings, nipple and pipe aren't that expensive; if you decide you want to replace yours, I have a brand new set I bought in desperation before I replaced the gasket.
- Thread starter
- #9
Aim, after watching the leak, it appears be coming from the area of the top shorter arrow you added to my pic. It looks like it's leaking from the backside of that pipe as it joins the water pump housing. The coolant then drips down and pools in the area where you see it in the photo. If you think your parts will fix my problem I'll gladly take them off your hands. Also, I did not change out the thermostat so I'm thinking you're on the right track.
From the top down, there is the (1) 16351-66010 Outlet Water By-Pass Pipe, a (2) 90301-29006 o-ring, a (3) 16268-66010 nipple with 2 more (4) 90301-29006 o-rings top and bottom. The reason I never replaced the parts because my nipple would not come out easily even when I had the timing cover on my bench.
The list and "smart shopper" should be close to
16351-66010 $37.61 / $28.00
16268-66010 $10.63 / $7.80
90301-29006 $4.63 / $3.45
I will PM you my contact details so that we do not derail this thread too much.
The list and "smart shopper" should be close to
16351-66010 $37.61 / $28.00
16268-66010 $10.63 / $7.80
90301-29006 $4.63 / $3.45
I will PM you my contact details so that we do not derail this thread too much.
The problem with this leak is that anything you try requires you to drain almost half of your coolant (unless some 'mud wizards have a better idea?). If the botom of the pipe is corroded on the inside like mine was, you will need oversize o-rings. The 16268 nipple was surprisingly clean in my case and would not come out.
Currently on my vehicle I have the original 16351 pipe with the bottom polished, a new o-ring at the top, an oversize o-ring at the bottom with ANOTHER even larger o-ring squashed at the top of the nipple and the original o-ring at the bottom of the original nipple. This joint (top of nipple/bottom of pipe) did leak (about 1/3 of the total leak in that area) despite new factory o-rings and does not leak now with oversize o-rings. If you buy the parts from a local dealer to have on hand so you don't have to keep draining coolant, you may be able to return them if you don't need them. That was my thinking, but I was embarrassed to return even more parts after my whole head gasket saga.
Best wishes!
P.S. I am still unclear about the wisdom of applying a thin coat of silicone to joints like this. I greased up a lot of stuff, but this particular joint on this particular go around is dry.
Currently on my vehicle I have the original 16351 pipe with the bottom polished, a new o-ring at the top, an oversize o-ring at the bottom with ANOTHER even larger o-ring squashed at the top of the nipple and the original o-ring at the bottom of the original nipple. This joint (top of nipple/bottom of pipe) did leak (about 1/3 of the total leak in that area) despite new factory o-rings and does not leak now with oversize o-rings. If you buy the parts from a local dealer to have on hand so you don't have to keep draining coolant, you may be able to return them if you don't need them. That was my thinking, but I was embarrassed to return even more parts after my whole head gasket saga.
Best wishes!
P.S. I am still unclear about the wisdom of applying a thin coat of silicone to joints like this. I greased up a lot of stuff, but this particular joint on this particular go around is dry.
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I have the same leak. I replaced just the o rings but that didn't fix it
- Thread starter
- #13
I've been watching this for a couple days. You can clearly see where it's leaking from in this photos. What is weird is that the coolant has gelled. I've never seen that before. What causes that?
