Lower radiator hose fitting leak
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From: Jasper GA
Lower radiator hose fitting leak
I've got a slight leak at the fitting for the lower radiator hose, coming from where it bolts to the water pump. It looks like there's no gasket in there, so I'm guessing it's a bad RTV job. Is there supposed to be a gasket in there, or do I just need to do a better job with the RTV?
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From: Jasper GA
Sorry this is my first LS-anything. I know the LT-5 very well, and ask me about Porsche, or a 308 engine. Still learning the layout of the LS1. Yep it's the thermostat housing and you're right, it is the o-ring seal. Mine is apparently leaking, yay. Draining the cooling system might be my least-favorite job working on cars.
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From: Jasper GA
Having a hard time figuring out if my car has the integrated thermostat/housing, or a separate setup. I think there was a change in 2004 but haven't been able to pin it down. I figure if I'm going in there, I might as well replace the thermostat too. Can someone point me in the right direction?
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From: North Georgia, USA
What year is yours? And how many miles?
Do you know what the service history is on yours? Have you gone to the local dealership and pulled a history on your VIN?
On most C5's, in the absence of actual receipts for service, I'd replace the thermostat and all the hoses if it were up to me. Those parts don't last forever, and they are getting old if they are factory originals.
PS. Check your private messages here.
Do you know what the service history is on yours? Have you gone to the local dealership and pulled a history on your VIN?
On most C5's, in the absence of actual receipts for service, I'd replace the thermostat and all the hoses if it were up to me. Those parts don't last forever, and they are getting old if they are factory originals.
PS. Check your private messages here.
Last edited by C6_Racer_X; Mar 25, 2018 at 07:17 PM.
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From: North Georgia, USA
GM VIS for your car is not going to tell you anything about which pump/thermostat the car has. It may have been changed by a previous owner and the GMVIS only shows what GM would have done to the car at their expense and even then PN's of repair/repacement components are not listed.
The very first picture in the link I provided above shows the T'stat cover of the newer style pump on the left. The one that uses the integrated T'stat is on the left and visually the two are very different as you can see from the picture. If you want to change the T'stat on the older style the T'stat is built into the cover and you replace the cover and T'stat as a unit. The older style uses an o'ring to seal. On the newer style the T'stat is a stand alone piece and reuses the T'stat cover. The seal is a rubber assembly on the body of the T'stat for the newer style.
The very first picture in the link I provided above shows the T'stat cover of the newer style pump on the left. The one that uses the integrated T'stat is on the left and visually the two are very different as you can see from the picture. If you want to change the T'stat on the older style the T'stat is built into the cover and you replace the cover and T'stat as a unit. The older style uses an o'ring to seal. On the newer style the T'stat is a stand alone piece and reuses the T'stat cover. The seal is a rubber assembly on the body of the T'stat for the newer style.
But @mark4cam lists his location as Jasper, Georgia, and there's only one Chevrolet dealership in Jasper. Many of the locals don't go very far with their cars. If he bought it from someone in Jasper or nearby, it's entirely possible that dealership has a more complete service history than GM VIS.
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From: Jasper GA
Thanks, appreciate the help. I updated my sig with my car info, but it's not showing up. It's a 2004 and comparing that link with mine it does look like I have the separate housing/thermostat and the hoses are likely original. It looks like my small leak repair will be a wholesale cooling system refresh, which is a good thing. Although I will say the temps are bang on perfect, zero issues there at all.
The car came out of Chattanooga, only has 38k miles on it, but sat outside for nearly 10 years without moving. History is nonexistent, carfax stops in 2008, and a dealer will certainly have nothing beyond that. I did a writeup of what I know in my thread Life with a Millenium Yellow C5, where I'm documenting my progress in bringing this car back to life. The guy I bought it from supposedly replaced the water pump, definitely put new coolant in, but apparently reused everything else.
The car came out of Chattanooga, only has 38k miles on it, but sat outside for nearly 10 years without moving. History is nonexistent, carfax stops in 2008, and a dealer will certainly have nothing beyond that. I did a writeup of what I know in my thread Life with a Millenium Yellow C5, where I'm documenting my progress in bringing this car back to life. The guy I bought it from supposedly replaced the water pump, definitely put new coolant in, but apparently reused everything else.
Last edited by mark4cam; Mar 26, 2018 at 06:19 AM.
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From: Jasper GA
There are a couple of items to consider here.
Given that the owner you purchased the car from replaced the WP while he owned it he may have installed a reman old style pump and tried to reuse the new style T'stat with the old style pump. This could easily result in a leak condition. Here is another link for you:
https://www.corvetteforum.com/forums...d-subject.html
Note that on the earlier style pump the opening for the T'stat is 2" while the opening on the new style is 1.86". This means that if the pump used was an old style reman unit (new copies of the old style have not been available for more that 10 years unless someone had a "new" old stock sitting on the shelf for a long time) then the new style T'stat (1.86") would fit inside the old style housing but the new style rubber sealing gasket most likely would NOT properly seal up. The old style pump was designed to be sealed up using an o'ring using the old style T'stat cover.
I have seen posts on this Forum where owners purchased reman old style pumps and tried to use them on a 2004 which requires the new style pump if you plan to reuse the new style T's stat and its cover. I can easily understand that there were plenty of old style pumps that could have been sent to a reman operation. The old style pumps were around from 1997 - 2003 so plenty of them.
I suggest that you will need to remove the T'stat cover and measure (inside micrometer or vernier caliper) the opening for the T'stat. If it is 2" you have a problem..
Given that the owner you purchased the car from replaced the WP while he owned it he may have installed a reman old style pump and tried to reuse the new style T'stat with the old style pump. This could easily result in a leak condition. Here is another link for you:
https://www.corvetteforum.com/forums...d-subject.html
Note that on the earlier style pump the opening for the T'stat is 2" while the opening on the new style is 1.86". This means that if the pump used was an old style reman unit (new copies of the old style have not been available for more that 10 years unless someone had a "new" old stock sitting on the shelf for a long time) then the new style T'stat (1.86") would fit inside the old style housing but the new style rubber sealing gasket most likely would NOT properly seal up. The old style pump was designed to be sealed up using an o'ring using the old style T'stat cover.
I have seen posts on this Forum where owners purchased reman old style pumps and tried to use them on a 2004 which requires the new style pump if you plan to reuse the new style T's stat and its cover. I can easily understand that there were plenty of old style pumps that could have been sent to a reman operation. The old style pumps were around from 1997 - 2003 so plenty of them.
I suggest that you will need to remove the T'stat cover and measure (inside micrometer or vernier caliper) the opening for the T'stat. If it is 2" you have a problem..
If this is the case, is it as simple as purchasing the old style thermostat/housing and using it? Or would I need to replace the water pump with the new style? Which I really don't want to do, no leaks and working perfectly.
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From: Jasper GA
Note that on the earlier style pump the opening for the T'stat is 2" while the opening on the new style is 1.86". This means that if the pump used was an old style reman unit (new copies of the old style have not been available for more that 10 years unless someone had a "new" old stock sitting on the shelf for a long time) then the new style T'stat (1.86") would fit inside the old style housing but the new style rubber sealing gasket most likely would NOT properly seal up. The old style pump was designed to be sealed up using an o'ring using the old style T'stat cover.
I would NEVER have figured this out without your input. THANK YOU!
Yes there are other things in this pic I need to replace as well, taking it one step at a time.
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From: Jasper GA
That is why it was leaking. Those two different design parts were NOT intended to go together.
Now you need to find an old style T'stat cover with the temp rated T'stat that you need. Or alternatively and likely much more expensive alternative of getting a newer style water pump and replacing the old style reman water pump that is now on the car.
Now you need to find an old style T'stat cover with the temp rated T'stat that you need. Or alternatively and likely much more expensive alternative of getting a newer style water pump and replacing the old style reman water pump that is now on the car.
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From: Jasper GA
Following up on this. I installed the old style thermostat, new radiator hoses and fresh dexcool. I filled according to the WSM procedure, then a nice drive watching the temps cycle exactly like they are supposed to. Back in the garage for a cool down, and no runs, no drips, no errors. Awesome.
I hope this thread benefits someone who has a persistent leak like I did. Tricky to diagnose without the experience on this forum. Love driving my car again!
I hope this thread benefits someone who has a persistent leak like I did. Tricky to diagnose without the experience on this forum. Love driving my car again!
