1989 3.8 Thermostat install
10-12-2017, 07:04 PM
#1
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1989 3.8 Thermostat install
Ok so I am trying to replace my thermostat on a 1989 Olds 3.8 and its not going well.
I have a new thermostat and thermostat seal and O ring for the water outlet. So, if understand this correctly
#1 Thermostat goes into manifold
#2 Thermostat seal goes on top of thermostat
#3 Thermostat housing goes on, and bolt is tightened down
These are the three steps I've been doing, problem is when I tighten the bolt the housing is not being drawn down evenly, once the bolt is tight I have a huge gap between the manifold and housing opposite the bolt. Any idea whats going on? I know I must be doing someting wrong.
As you can see in the pic the housing is pretty corroded...should I get a new one?
Thanks!
I have a new thermostat and thermostat seal and O ring for the water outlet. So, if understand this correctly
#1 Thermostat goes into manifold
#2 Thermostat seal goes on top of thermostat
#3 Thermostat housing goes on, and bolt is tightened down
These are the three steps I've been doing, problem is when I tighten the bolt the housing is not being drawn down evenly, once the bolt is tight I have a huge gap between the manifold and housing opposite the bolt. Any idea whats going on? I know I must be doing someting wrong.
As you can see in the pic the housing is pretty corroded...should I get a new one?
Thanks!
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JScatt (10-13-2017)
10-13-2017, 01:00 AM
#3
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Jeeze, I always did hate this setup...
If I remember right, the steps are as follows:
Seal goes on thermostat
Thermostat gets shoved in housing (sometimes a dab of rtv goop can help it stick if you need it)
Housing presses in to manifold
Cleanup with a wire brush goes a long way, and I believe there is also an o-ring on the housing that should be tended to as well. Also, a touch of lubricant (coolant prolly) on the o-ring works wonders. Don't use the bolt to drive the housing in to the manifold, it'* just there to lock it down once it'* in. I favor the circular rocking approach once you get it started.
Haven't had to do one for a long time, but it sounds familiar after looking up how rock auto replacement parts look.
If corrosion is causing a leak, or inhibiting progress, replacement may be the favorable alternative.
If I remember right, the steps are as follows:
Seal goes on thermostat
Thermostat gets shoved in housing (sometimes a dab of rtv goop can help it stick if you need it)
Housing presses in to manifold
Cleanup with a wire brush goes a long way, and I believe there is also an o-ring on the housing that should be tended to as well. Also, a touch of lubricant (coolant prolly) on the o-ring works wonders. Don't use the bolt to drive the housing in to the manifold, it'* just there to lock it down once it'* in. I favor the circular rocking approach once you get it started.
Haven't had to do one for a long time, but it sounds familiar after looking up how rock auto replacement parts look.
If corrosion is causing a leak, or inhibiting progress, replacement may be the favorable alternative.
10-13-2017, 05:54 AM
#4
Senior Member
True Car Nut
This is on a Delta 88 right?
You might be able to clean that up well enough, but looking at that pitting in some parts of it, if it were me I'd order a Dorman replacement from RockAuto, it is only 10.14 plus shipping.
DORMAN 9022025 is the part number.
You might be able to clean that up well enough, but looking at that pitting in some parts of it, if it were me I'd order a Dorman replacement from RockAuto, it is only 10.14 plus shipping.
DORMAN 9022025 is the part number.
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JScatt (10-13-2017)
10-13-2017, 10:09 AM
#5
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Nope, it came out in one mangled piece. I just think its overly corroded, gunna try a new housing.
I will give that a try! I think I will get a new housing because my old one is corroded(even after cleaning) that the groove for the T-stat seal is almost non existent.
Thanks!
Jeeze, I always did hate this setup...
If I remember right, the steps are as follows:
Seal goes on thermostat
Thermostat gets shoved in housing (sometimes a dab of rtv goop can help it stick if you need it)
Housing presses in to manifold
Cleanup with a wire brush goes a long way, and I believe there is also an o-ring on the housing that should be tended to as well. Also, a touch of lubricant (coolant prolly) on the o-ring works wonders. Don't use the bolt to drive the housing in to the manifold, it'* just there to lock it down once it'* in. I favor the circular rocking approach once you get it started.
Haven't had to do one for a long time, but it sounds familiar after looking up how rock auto replacement parts look.
If corrosion is causing a leak, or inhibiting progress, replacement may be the favorable alternative.
If I remember right, the steps are as follows:
Seal goes on thermostat
Thermostat gets shoved in housing (sometimes a dab of rtv goop can help it stick if you need it)
Housing presses in to manifold
Cleanup with a wire brush goes a long way, and I believe there is also an o-ring on the housing that should be tended to as well. Also, a touch of lubricant (coolant prolly) on the o-ring works wonders. Don't use the bolt to drive the housing in to the manifold, it'* just there to lock it down once it'* in. I favor the circular rocking approach once you get it started.
Haven't had to do one for a long time, but it sounds familiar after looking up how rock auto replacement parts look.
If corrosion is causing a leak, or inhibiting progress, replacement may be the favorable alternative.
Thanks!
10-13-2017, 03:07 PM
#6
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Thanks!
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WilliamE (10-13-2017)
10-13-2017, 03:19 PM
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Ok, what is the point of this stupid thermostat seal? If you already have an O ring on the housing why to you need another seal on the thermostat?
I went to the junkyard and got another housing which is in great shape, no pitting/corrosion. When I pulled the housing off of the junkyard car there was NOT a thermostat seal being used.
I tried to install again with t-stat seal and all the pushing and twisting I could muster couldn't get it to seat correctly, took out the thermostat seal and and the housing seats perfectly.
I think the Fel-Pro 35126 T-Stat seal is not designed correctly, its way to fat and looks different than the original.
Seems the only GM seals(12337901)available are sold in bags of 12 on Ebay
I went to the junkyard and got another housing which is in great shape, no pitting/corrosion. When I pulled the housing off of the junkyard car there was NOT a thermostat seal being used.
I tried to install again with t-stat seal and all the pushing and twisting I could muster couldn't get it to seat correctly, took out the thermostat seal and and the housing seats perfectly.
I think the Fel-Pro 35126 T-Stat seal is not designed correctly, its way to fat and looks different than the original.
Seems the only GM seals(12337901)available are sold in bags of 12 on Ebay
10-13-2017, 04:42 PM
#8
Senior Member
True Car Nut
It'* there to stop coolant from flowing past the thermostat when it'* closed. I also feel like the seal was easy to put on upside down.
I think the worst case scenario with no seal is that too much coolant flows past the thermostat when closed, and it prevents it from maintaining operating temperature (too cold while driving)
I think the worst case scenario with no seal is that too much coolant flows past the thermostat when closed, and it prevents it from maintaining operating temperature (too cold while driving)
10-13-2017, 06:02 PM
#9
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It'* there to stop coolant from flowing past the thermostat when it'* closed. I also feel like the seal was easy to put on upside down.
I think the worst case scenario with no seal is that too much coolant flows past the thermostat when closed, and it prevents it from maintaining operating temperature (too cold while driving)
I think the worst case scenario with no seal is that too much coolant flows past the thermostat when closed, and it prevents it from maintaining operating temperature (too cold while driving)