Changing the thermostat questions

[Tackettr]

This thread has been very helpful to me. I plan on changing my thermostat as soon as the weather allows. Thanks to everyone.

As for the hoses, are they common sizes that can be picked-up at NAPA also?

 

[randyscycle]

This thread has been very helpful to me. I plan on changing my thermostat as soon as the weather allows. Thanks to everyone.

As for the hoses, are they common sizes that can be picked-up at NAPA also?

All of the hoses were common sizes available as straight hose at NAPA, except for the lower radiator hose which is a formed hose. I was still able to find a hose that was close enough and cut a section out of it. The large hoses are 2" and the manifold hoses were 1-3/4". The heater hoses (if you have a heater) are 5/8".

 

[Michael]

NAPA sells it in approximately 2 foot sticks you can cut it yourself or they will cut it to length for you in the store.

 

[Beerslayer]

More Thermostat Seal Part Numbers

Thermostat Housing Seal:
Napa THM 4662
Carquest 30981
Cummins 188318
DSU Peterbuilt 5125235 5134269
Stant 25010
White 1601173 483183

Thanks for all the help everyone!

 

[LiqTenEXp]

I need the seal for the t-stat housing to block. Anyone know what that PN is from NAPA?

 

[Beerslayer]

I need the seal for the t-stat housing to block. Anyone know what that PN is from NAPA?

Permatex?

 

[Jake0147]

I hammered out a gasket for that one. Those rolls of gasket material are pretty handy for lots of little gaskets that are difficult to find late Sunday evening when you're trying to wrap something up...

 

[JCKnife]

I picked up a new thermostat and seal from NAPA the other day and have them laying here right now on my desk.

The thermostat is part number 358-180 and the seal part number 4622. THe seal does fit the thermostat and can be pushed on by hand. I just did it. It is snug, but can be done without any serious force. Seems that it would work just fine. I will install it next weekend, so if any problems, I'll be glad to post up.

I realize this is an old thread but I'm getting ready to tackle my thermostat. NAPA does not show anything for part # 4622 as stated above, but for the 358-180 thermostat they have the seal part # 4661 with these attributes:

Water Outlet Seal ID: 2.27"
Water Outlet Seal OD: 2.66"
Water Outlet Seal width: .25"

THink this'll work? I haven't read the TM yet on this, I'm at work.

Deuce is running hot and spitting coolant out the rad cap after I shut her off.

 

[Aurora]

the seal is 4662, there is a typo above. i just bought one at napa yesterday-going to install this weekend.

 

[JCKnife]

Yeah I see that now--4662. Thanks!

 

[Wildchild467]

I know this is an old thread, but Welldigger said to replace the seal because if you don't, it will run cold around town and hot down the highway. I'm not sure what condition the seal has to be in, but mine was intact when I (actually 74M35A2 changed it for me) changed it. I put in the Napa thermostat referenced in this thread. My issue is that the truck runs very cool. It is advertised as a 180 degree thermostat and when it is 50 degrees out, it will only run about 160 degrees. The cooling system is full, I am sure of that. I just don't know what it could be that makes it run so cool. I put the winter front cover on it and that helps out a lot. I just wish the engine temp could get to 180 degrees easier and stay there in not so cold temps. Any suggestions?

Also I think there is confusion in this thread saying the seal number is 4662 and in another spot is says it is 4622 (in post #17). I checked the same post that says the seal number is 4622 and his picture shows the seal as part number 4662. He just made a typing error. Maybe one of the moderators could correct this if possible? Thank you if you can.

 

[ralph3162]

I bought my truck in Colorado in the month of Feb. -24 degrees ran about 140 to 160 with front half open all the way to Texas. It had cold weather front on it. Never got very warm unless I closed the front flap all the way then would start to over heat. I took off the cold weather front when I got to Texas I have and drive it hear in Texas don't think I have ever gotten above 120 except when I have been driving highway and then as I drive around town temp will go up when I stop for lights, but as soon as I start moving again she cools back down and almost never registers on temp gauge. Temp gauge is good thermostat is good and plenty of coolant just seems to run cool but heater and defrost work good when used.

 

[rustystud]

Actually you do not need to replace this seal around the thermostat unless it is torn or otherwise damaged. Almost all industrial engines use this style of thermostat and seal. I have replaced countless thermostat's and have only replaced this seal maybe 10 times ( OK maybe 20 ). If you do decide to replace it, make sure you install it straight in. Any cocking in the bore will make installing the thermostat extremely difficult, and can tear the seal.

 

[rustystud]

I bought my truck in Colorado in the month of Feb. -24 degrees ran about 140 to 160 with front half open all the way to Texas. It had cold weather front on it. Never got very warm unless I closed the front flap all the way then would start to over heat. I took off the cold weather front when I got to Texas I have and drive it hear in Texas don't think I have ever gotten above 120 except when I have been driving highway and then as I drive around town temp will go up when I stop for lights, but as soon as I start moving again she cools back down and almost never registers on temp gauge. Temp gauge is good thermostat is good and plenty of coolant just seems to run cool but heater and defrost work good when used.

Around here in the West side of Washington I have to drive my truck with the winter cover on to get the temperature up to at least 170 degrees in the winter. Most times I just use a piece of heavy cardboard on the front of the radiator. For an engine with such high compression it sure runs really cold !

 

[Wildchild467]

When the thermostat opens and closes, does it slide on that seal? If so, could an older seal be harder and make it tougher to move and make the thermostat not work as good?

 

[LowTech]

No. Only the middle part should move.

 

[JasonS]

In my truck, that middle part rode against the seal and there was clear evidence of wear against the brass thermostat.

 

[welldigger]

I know this is an old thread, but Welldigger said to replace the seal because if you don't, it will run cold around town and hot down the highway. I'm not sure what condition the seal has to be in, but mine was intact when I (actually 74M35A2 changed it for me) changed it. I put in the Napa thermostat referenced in this thread. My issue is that the truck runs very cool. It is advertised as a 180 degree thermostat and when it is 50 degrees out, it will only run about 160 degrees. The cooling system is full, I am sure of that. I just don't know what it could be that makes it run so cool. I put the winter front cover on it and that helps out a lot. I just wish the engine temp could get to 180 degrees easier and stay there in not so cold temps. Any suggestions?

Also I think there is confusion in this thread saying the seal number is 4662 and in another spot is says it is 4622 (in post #17). I checked the same post that says the seal number is 4622 and his picture shows the seal as part number 4662. He just made a typing error. Maybe one of the moderators could correct this if possible? Thank you if you can.

I said what? Lol. I don't remember that but maybe I said it.

What I do normally tell people to never remove the thermostat and run the truck unless it's an emergency. Diesels need the thermostat to keep cylinder temperatures up. This ensures a more complete combustion and prevents wet stacking. Without a thermostat diesels will run cold.

As far as changing the seal around the thermostat I would only worry about it if the seal is noticeably damaged. Otherwise, change the thermostat itself and roll on. Even if a little coolant seeps past the seal when the thermostat is closed that's no big deal.

I would be sure to have a new thermostat housing gasket or some rtv just so the housing doesn't leak.

 

[rustystud]

I said what? Lol. I don't remember that but maybe I said it.

What I do normally tell people to never remove the thermostat and run the truck unless it's an emergency. Diesels need the thermostat to keep cylinder temperatures up. This ensures a more complete combustion and prevents wet stacking. Without a thermostat diesels will run cold.

As far as changing the seal around the thermostat I would only worry about it if the seal is noticeably damaged. Otherwise, change the thermostat itself and roll on. Even if a little coolant seeps past the seal when the thermostat is closed that's no big deal.

I would be sure to have a new thermostat housing gasket or some rtv just so the housing doesn't leak.

Welldigger, you never said that, it was from WillWagner. So your not loosing your mind, at least yet

 

[welldigger]

Welldigger, you never said that, it was from WillWagner. So your not loosing your mind, at least yet

Hey it wouldn't be the first time I said something and forgot.