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Discussion Starter · #1 · (Edited)
I have a cooling system problem. The thermostat housing had a slow drip and my temperature would shoot up to near maximum when the car was stationary and then instantly drop down to normal once the car moved. I thought I had a bad thermostat so I replaced it.

I think air got into my cooling system and an air pocket formed when stationary and then the air pocket moved when the car moved. I have a cracked head gasket and need to top up coolant once a month but couldn't get around to it soon enough and it ran empty, so I think air got in through the empty overflow tank.

The thermostat housing is still dripping and now the thermostat outlet hose leaks where it connects to the thermostat housing. Also, there is now coolant leaking from behind the engine.

I haven't been able to find out yet where the leak behind the engine is coming from because my car can't start as I have a blown battery fuse. A replacement fuse will arrive shortly so I'm hoping others can provide me with their thoughts to give me a head start in diagnosing the problem. :)

What do others think?

I really hope it's not the water pump.
 

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If it's behind the car it's not the water pump, I'd get one of those pressure test kits off ebay. It will pressurize the system without the car being on or hot. Then you can look underneath and see exactly where's it dripping. My guess it's the water pipe going from the thermostat housing to the water pump. The O rings go bad sometimes.
 

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Discussion Starter · #3 ·
I thought it might be the water pump because it has two rear directing bleed holes. There is no coolant around the timing belt covers so it's probably not the water pump.

Thanks for the info on the pressure tester kit. I was thinking of them today. My fuse should arrive in the post on Monday so I will be able to start the car then and find where the leak is coming from.

Hmmm. My understanding is that hoses don't use o-rings. Did you mean something else perhaps?
 

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I thought it might be the water pump because it has two rear directing bleed holes. There is no coolant around the timing belt covers so it's probably not the water pump.

Thanks for the info on the pressure tester kit. I was thinking of them today. My fuse should arrive in the post on Monday so I will be able to start the car then and find where the leak is coming from.

Hmmm. My understanding is that hoses don't use o-rings. Did you mean something else perhaps?
Welcome to 3rd gen hell hehe 😉 there is a coolant pipe that goes from the left side to the right side looking from drivers seat perspective. There is no aftermarket replacement for said pipe but there is an O ring that does dry out with time. Those however are still used in new accords so you can get one from a parts store. I believe the correct term for this part is water pump return pipe and in the US they can rust away and leave us with big leaks. Also, these can only be truly accessed with a lot of taking things apart. I’ve heard people take the motor out and I think people have taken the axles out. I personally took the intake plenum fuel rail and manifold to get to mine. However you do it it is no easy task.
 

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1989 Accord LXi Coupe; 1989 Prelude 2.0s; 1964 Dodge Dart GT: 1993 Kawasaki ZX-11; 1982 Honda CB900
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Behind the engine is most likely one of the many rubber hoses back there that are over 30 years old & is leaking. Even Japanese rubber doesnt last forever. Low water levels, (air pockets), can cause wrong temp info to be sent to the fan unit. Fan doesnt turn on, temp gauge climbs, blown head gasket.
 

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Discussion Starter · #6 ·
Eiselbee3

Oh, I thought that pipe was welded onto the engine. Thanks for the suggestion, I will check it if I can't find any bad hoses.

I really hope it's not the pipe! I will almost certainly get rid of the car if it is.


Blainethemono

I think you are right on it. Let's hope it something easy. I already have spare hose coming in the mail as I am expecting it to be one of the hoses.
 

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Hmmm. My understanding is that hoses don't use o-rings. Did you mean something else perhaps?
I'm talking about the water pipe, it's a metal tube going from the water pump to the thermostat housing, it uses 2 o rings.

I really hope it's not the pipe! I will almost certainly get rid of the car if it is.
Nooo! It's not that hard to replace. Take your intake off if you need to. Save the 3rd gen!
 

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Discussion Starter · #8 · (Edited)
There is no pipe going to the thermostat housing on my 91'. The only thing like a pipe on my thermostat housing is the upper radiator hose.

I can't remove the intake manifold because it requires a couple of new gaskets to put it back on. I don't have time to find/wait for new ones to arrive. Thanks for the suggestion anyway. :)
 

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Discussion Starter · #12 ·
haha thanks man! I don't even have time for that! Any bull shit next week and the car is gone! I've already been reviewing tow truck wreckers to come and take it away. My battery fuse should arrive tomorrow for another problem that I have fixed but have yet to test. If I start it tomorrow which is the test and the problem persists, that's it! The car will be gone by then end of the week!
 

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haha thanks man! I don't even have time for that! Any bull shit next week and the car is gone! I've already been reviewing tow truck wreckers to come and take it away. My battery fuse should arrive tomorrow for another problem that I have fixed but have yet to test. If I start it tomorrow which is the test and the problem persists, that's it! The car will be gone by then end of the week!
Just get rid of it then, go buy a 2021 that doesn't have any problems.
 

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Discussion Starter · #15 ·
So I had my car running for an hour today. Strangely, there wasn't a leak from the back of the engine. Now I'm wondering if there ever was a leak from the back of the engine and if perhaps the leak coming from where the alternator housing and upper radiator hose connects traveled across to the other side.

Here is a photo of the leak from today. My neighbours love me! \o/ lol

29325


29326


I have another problem to fix first but once I fix it I will get back to fixing this radioactive disaster.
 

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1989 Accord LXi Coupe; 1989 Prelude 2.0s; 1964 Dodge Dart GT: 1993 Kawasaki ZX-11; 1982 Honda CB900
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Ah yeah. If it's that then this car's off to the wreckers. I'm not fixing that bull shit. :)

If I could tear it all way down and make sure it wasnt the pipe, YOU CAN TOO!!!! My pipe was perfectly fine.

P.S. the 1/2" rip in the hose that dumped ALL my coolant within 5 blocks dumped it EXACTLY where you anti-freeze is sitting when I stopped. Had to stop and fill up a 1 gallon jug 5 times before I got home.. Didnt warp the head!!! The hose that blew was #22

P.S.S. Might as well tow it to the junk yard and tell us where its at, because to replace the hose that blew u can also R&R the pipe cuz its THAT deep under a bunch of shit.
 

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Discussion Starter · #17 · (Edited)
I can't see a hose leaking, only the leak at the joint where the upper radiator hose connects to the thermostat housing. Replaced the thermostat and gasket, problem persists.

Now that there is no leak from behind the engine things are very uncertain. Now I need to fix my other problem before resuming this one as I have a battery charge problem and can't run the car for diagnosing this leak.

The car is no longer overheating as well. It's so strange.

One thing about this car is it's cooling system behaves differently when the car is on an incline like it is in the photos. The cooling fan doesn't come on after switching off the engine when the car is on an incline so perhaps the incline has something to do with the inconsistent behaviour. Once I fix the other problem I am going to take off the air intake and have a very good look at the thermostat housing and upper radiator hose. I'll remove the upper radiator hose as well and inspect it.
 

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I can't see a hose leaking, only the leak at the joint where the upper radiator hose connects to the thermostat housing. Replaced the thermostat and gasket, problem persists.
Where exactly is it leaking from? Between the housing and the neck? Or between the cylinder head and the housing? Or from where the hose connects to the neck? All of these are easily repairable if you just use a little logic, a new gasket, and maybe a little ultra grey silicone. Your threads are absolutely infuriating to read because you don't really listen to anyone, and you have zero patience.
 
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