The good news is this is past you now.....and the bad news is the rest of us are going to start compulsively checking this area for leaks!
(I've already replaced the radiator and waterpump)....seems like this should be next on the list!
Kind of "Mystery" Coolant leak back of engine (heat exchanger valley leak) (6 Viewers)
- Thread starter cc93cruiser
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(I've already replaced the radiator and waterpump)....seems like this should be next on the list!
cc93cruiser
CRUZAHEAD
- Thread starter
- #22
As mentioned before, the job is not too technical just kind of hard to remove certain bolts/nuts. The main parts to remove when resealing the heat exchanger is the air intake filter box along with the plastic intake manifold... Then you have to remove the water pump bypass tube (4 bolts, posted pic) in order to remove the the 2 plastic air injection tubes that run from the front of engine all the way to the air injection valves in the back of the engine..Then it's just a matter of removing the plastic crankcase oil separator and then the dual air injection valves...Hardest was the 4 bolts on each side of the dual air injection valves at the very back of engine valley in between the cylinder heads.. The 2 bolts on the left hand side metal bypass was a bitch ( 1 bolt will not allow you to remove/put a wrench etc on because it's a super tight area where that certain bolt will not clear the wall of cylinder head)..... You have to remove the 3 bolts holding the air injection valves/ pumps to the block and then remove the 2 bolts on the right hand metal bypass tube.. This will allow you to grab the air injection valve and slightly bend the left metal bypass tube up and back so you can clear the cylinder head and then remove the 2 bolts from that left bypass tube... I posted a pic to show what bolts to remove in that order.. After that, it's just a matter of resealing and replacing the 2 orings in the union pipe that attaches the heat exchanger to the waterpump iirc... Here's a couple of pics... First pic is the 4 bolts you have to remove for the water inlet tube to remove the 2 plastic air injection tubes.. 2nd pic is the order in which you should remove the air injection valve bypass tubes in order to clear the left hand cylinder head..
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Thank you guys, this is very helpful. I am going to be jumping into this in the next week or two. I will post an update when I am finished or stuck.
I’d investigate removing the SAIS nonsense as long as the intake manifold was off. I believe the Hewitt kit has blankoff plates that allow full removal? Might require a backing plate to be fabbed if the pump side plumbing was removed. The pumps or valves will fail at some point. I tend to subscribe to the ‘while you’re in there’ mentally.
I fell victim to the dreaded 80’s head gasket failure and got stranded in Utah for 2 weeks a few years ago! Then in Colorado, I had an issue with a fusible link and couldn’t start. Also had the starter go but was able to get it started again by banging on it a couple times - thankfully I wasn’t far from home. water pump replacement, radiator...
My point of course is that 80’s have their issues too!
Does anyone happen to know the part numbers for the 2 orings in the union pipe that attaches the heat exchanger to the waterpump
If you get a chance, can you please explain what you are talking about here? I thought I was semi-literate about most things mechanical, but clearly I have a lot yet to learn!
Thanks,
DN
The Secondary Air Injection System (SAIS) injects air directly into the exhaust ports to help with cold start emissions. It consists of two large pumps in the passenger fender well, two control valves at the back if the engine under the manifold, and a system of connected tubing. Either the valves or the pump eventually will fail. Rather than repairing them, some people install a bypass kit from Hewitt to enable the removal without throwing codes. If I had the manifold off, I'd likely perform that delete and just get the valves and tubing out permanently. The kit is designed to allow the user to abandon the system in place rather than requiring its removal and the blank off plates included are designed to fit between two stronger flanges, so my guess is you would need to fab up two thicker backup plates to go on the valve side of the manifold.
Well put. Thanks.
Part number is 96761-
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Unfortunately, common. Had mine already weeping when the radiator was leaking at 95k miles or so. So I went ahead and paid dealer. $2k later.....no leaks with new water pump, radiator and valley leak fixed.
Shouldn't there be 2 exhaust manifold gaskets?
I am asking as I was ready to do this, this weekend but realized I didn't have the manifold and exhaust gaskets. Most have been saying you just need the O rings.
I just had this job done and within 3 weeks its leaking coolant again and now I also have a new exhaust noise after the truck warms up. I thought the exhaust manifold area leak was a coincidence but now understand probably not when I see all of what is involved with the heat exchanger plate removal. Is 11 hours labor correct for the heat exchanger reseal? I have seen numbers all over the place for the job.
bloc
SILVER Star
I have no idea what the book schedule says for this but from reading on here and poking around on my truck I believe the intake manifold is actually pretty easy/quick to remove. Which is the main thing in the way.
But, it LOOKS like a ton of work.. and the job can probably be sold to vehicle owners that way.. which might explain the big difference in quotes.
It doesn’t help you at all but my wild ass guess is I could get it done in a half day in my driveway assuming no issues come up.
This P/N is not correct, should be 96761-35035
My favorite online discount parts website has them for $3.18 each.
I was able to do it in less than 11 hours. It is a real pain in the ass though. Having small hands will make a huge difference. I spent several hours on 4 bolts in the back on the SAIS valve pipes. Little hands would have cut that time to under an hour.
You don't touch the exhaust manifold though, just the air intake manifold.
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I now have an exhaust leak I smell under the hood and I get some exhaust noise after the truck warms up, if the air injection system or lines were somehow messed up, could it allow exhaust noise?
I don't know that much about the SAIS system. I believe it may connect to the exhaust system but can't say for sure. I know the pipes are routed over the exhaust manifold as that is where I had to put in the blocking plates. I just don't know where those pipes end up at.
I am sure there are much smarter people on this board who will have that answer for you. Sorry.
Doesn’t the air injection system pull air from the intake manifold area and dump it into the exhaust manifold before the catalytic converters?
