Which brand thermostats?

[Summit_Rider]

I need new thermostats for my lb7. Rock auto has Motorad, stant, gates, and ac delco. I figured I’d go with ac delco just to be safe. Problem is they have two different styles of ac delco t-stats.

http://www.rockauto.com/en/catalog/...harged,1431804,cooling+system,thermostat,2200

Here’s a link what do you guys recommend?

 

[CarolinaHD]

You have 2 thermostats, front and rear, it says it right in the description. You need to order both and put them in the right location.

 

[Summit_Rider]

Ya I understand that. I’m fully aware I need a front and rear. Maybe re read my post. I never asked how many I have, I asked which brand to get and wondering the difference between the two styles of ac delco.

 

[CarolinaHD]

Ah i see, AC Delco original equipment is just that and AC Delco professional are non oem parts made under the same name, usually of lesser quality and from a different plant than the oem stuff. Im ASSuming they did this to compete with the parts store brands.

Get the more expensive OEM ones

 

[Summit_Rider]

Gotcha. I was leaning towards the more expensive ones. Thank you sir.

 

[Chevy1925]

Don’t buy the cheap ac delcos. Stick with the oem ones or gates.

 

[Summit_Rider]

The gates are considerably cheaper. I’ve run gates in a few different gas vehicles with success in the past. Ughh I hate decisions.

 

[PureHybrid]

FWIW the last gates thermostats I bought said made in China, and one said Motorad. Maybe it was a return that someone switched out? Either way I installed them and they worked.

 

[Summit_Rider]

FWIW the last gates thermostats I bought said made in China, and one said Motorad. Maybe it was a return that someone switched out? Either way I installed them and they worked.

Good to know. I’m not much of a made in China fan.

 

[Summit_Rider]

I bit the bullet and just ordered the more expensive oem ac delco t-stats. What’s $30 in the world of diesels.

 

[Robby Avery]

Make sure you vac n fill it so as to not have any air pockets not sure of the mileage on the op truck don't want hot spots can lead to other problems down the line fwiw :thumb: as mentioned in earlier posts there are two one is a 180 deg and the other is a 185 deg thermostat. when the housing is removed note the location of the old ones and swap new in the correct order also lightly clean mating surface with Emory cloth and brake clean to remove and potential leak particles just my way of doing it. The mentioned vac n fill method Uview makes a super nice kit/tool set check google as prices vary. Hope this helps

 

[Summit_Rider]

Make sure you vac n fill it so as to not have any air pockets not sure of the mileage on the op truck don't want hot spots can lead to other problems down the line fwiw :thumb: as mentioned in earlier posts there are two one is a 180 deg and the other is a 185 deg thermostat. when the housing is removed note the location of the old ones and swap new in the correct order also lightly clean mating surface with Emory cloth and brake clean to remove and potential leak particles just my way of doing it. The mentioned vac n fill method Uview makes a super nice kit/tool set check google as prices vary. Hope this helps

I just had the thermostat housing off a few months ago when I changed my injectors. In fact I drained the whole coolant system. I didn’t vac n fill after putting it back together. I just filled it, let it get to operating temp and topped it off. No issues. This is how I’ve done it on every diesel I’ve ever worked on. Is it really necessary? On some gas motors I’ve worked on the t-stat housing had a bleeder valve. If it was a big deal why wouldn’t gm put a bleeder valve on the t-stat housing?

 

[THEFERMANATOR]

Just an fyi to look out for, I put new AC DELCO OEM styles in my LB7 the 1st of the year. They came in the GM boxes and looked to be the real deal. Put them in and they don't open until 190 and 195. I haven't really worried about it as I don't mind it running a bit warmer since I don't tow much anymore. But it went from running 180 idling and 185 running down with my old stats(before the rubber seal failed on one), to idling at 188-190, and running 195 down the road.

 

[TheBac]

I just had the thermostat housing off a few months ago when I changed my injectors. In fact I drained the whole coolant system. I didn’t vac n fill after putting it back together. I just filled it, let it get to operating temp and topped it off. No issues. This is how I’ve done it on every diesel I’ve ever worked on. Is it really necessary? On some gas motors I’ve worked on the t-stat housing had a bleeder valve. If it was a big deal why wouldn’t gm put a bleeder valve on the t-stat housing?

There is one. The greenish bolt in the center of the housing.

 

[Robby Avery]

I just had the thermostat housing off a few months ago when I changed my injectors. In fact I drained the whole coolant system. I didn’t vac n fill after putting it back together. I just filled it, let it get to operating temp and topped it off. No issues. This is how I’ve done it on every diesel I’ve ever worked on. Is it really necessary? On some gas motors I’ve worked on the t-stat housing had a bleeder valve. If it was a big deal why wouldn’t gm put a bleeder valve on the t-stat housing?

That's is correct but you still have the chance of an enclosed air pocket in the reservoir and possibly the top of the radiator they are slightly higher than the bleeder screw in the t-stat housing. leading to a possibly trapped air pocket that could make its way into the block and or head and stay put causing a hot spot yes theory says the water pump moves fluid theory also says coolant expands and the air should self bleed in to the reservoir. me personally I vac and fill everything I turn a wrench on really don't like nor want come backs you know:thumb:

 

[Robby Avery]

Just an fyi to look out for, I put new AC DELCO OEM styles in my LB7 the 1st of the year. They came in the GM boxes and looked to be the real deal. Put them in and they don't open until 190 and 195. I haven't really worried about it as I don't mind it running a bit warmer since I don't tow much anymore. But it went from running 180 idling and 185 running down with my old stats(before the rubber seal failed on one), to idling at 188-190, and running 195 down the road.

I noticed the same thing when I did mine in Oct 2016 my 02 at the previous chevy dealership I worked at truck held 28 in of mercury when I vac and filled it though showing me I had no leaks :thumb: I just figured it was some of gm's redesign to address emission concerns with newer as well as older vehicles still on the road.

 

[Summit_Rider]

There is one. The greenish bolt in the center of the housing.

I just went and looked. You are correct. Don’t know how I missed that.

 

[Summit_Rider]

That's is correct but you still have the chance of an enclosed air pocket in the reservoir and possibly the top of the radiator they are slightly higher than the bleeder screw in the t-stat housing. leading to a possibly trapped air pocket that could make its way into the block and or head and stay put causing a hot spot yes theory says the water pump moves fluid theory also says coolant expands and the air should self bleed in to the reservoir. me personally I vac and fill everything I turn a wrench on really don't like nor want come backs you know:thumb:

Gotcha. I don’t doubt vac n fill is a better way of doing it.

 

[THEFERMANATOR]

I always take the small hose loose at the radiator above the trans cooler lines and clamp it off. That way I can burp out the top of the radiator. I will even put a floor jack or park it so that side of the radiator is higher. Fill it up, run it until the stats open a few times, let it cool down some, then take that hose loose and burp the air out of the top of the radiator. Has worked very well for me.

 

[Robby Avery]

I always take the small hose loose at the radiator above the trans cooler lines and clamp it off. That way I can burp out the top of the radiator. I will even put a floor jack or park it so that side of the radiator is higher. Fill it up, run it until the stats open a few times, let it cool down some, then take that hose loose and burp the air out of the top of the radiator. Has worked very well for me.

I like that idea you must be or have been a field service engineer/technician or have been in the past. Think on your feet and in a hurry:thumb: