Thermostat Housing

[Kerben]

Hello Everyone,
I'm having issues with my coolant temp. My temp gauge is reading hot, but it doesn't seem that it actually is hot. I was thinking that maybe I have a bad thermostat, so I go to change out the thermostat and the lower bolt on the thermostat housing has been stripped out to just about nothing by the previous owner. I've tried just about everything short of drilling it out. I guess I have two questions here... What do y'all suggest I do with this stripped out bolt and where can I find a replacement bolt? and... Is there another reason my gauge would be reading hot when it is not running hot?


Thanks,
Karl
93' D250 Cummins Dually extended cab - Flat Bed

 

[BSeyler]

I know it's after the fact, but I always verify questionable temperature readings with an infrared temperature gun. It's also a very handy tool to keep in the pickup when traveling to check tire and hub temps, etc.



If the threads are pulled, you are going to have to drill and tap to the next size. I don't know what that will be without pulling one - sorry. Good luck with your repairs!

 

[B.G. Smith]

Take the good bolt from the thermostat with you t a good auto supply store and buy a helicoil kit for the stripped bolt and get a matching bolt for the good one. The kit will come with a drill bit, a tap and a helicoil and helicoil inserter. Everything on the trucks is metric now but I don'tknow about 93. If the bolt should be 5/16" or 3/8" standard I probably have a helicoil for it. bg

 

[DVolk]

On the thermostat if its not a OEM cummins one its probally reading wrong , get a cummins one , there they will have a replacement bolt or stud for it . Is there a bolt or stud in it now ? if so if its a bolt and is broke off get a good EZ out , i like the low base ones from snap-on if its a stud craftsmen has some stud or rounded off bolt removers , if its out you can do a helicolil although there is plenty of material towere you cold just go up 1 size then bore out the thermostat housing and should be no reason to have to drill your block just use plenty of silicone on that bolt

 

[JMDancoe]

First of all is the head stripped off or are the bolt hole threads stripped out?

If it is the head stripped, make sure you use only a 6 point socket (only saying this, as I don't know your mechanical ability). If you are already using a 6 point, you can "try" changing from metric to the next size smaller standard (sae) size and drive it onto the head. I have removed a few this way. If that fails, its the easy-out route, or "very carefully grind (dremmel tool) the head off and remove the housing and then work at removing the remaining "stud". Be sure to soak it well in a good penetrating oil.

If it is a stripped bolt hole, helicoil or drilling and tapping oversize is the only way to go.

By all means get an infared gun for the future and "keep it in the truck" as they are very useful to answer "most" heat related problems. They are not expensive - check out Harbor Freight if you have one in your area or your local parts store.

Good luck with this.

 

[mwilson]

Hello Everyone,

I'm having issues with my coolant temp. My temp gauge is reading hot, but it doesn't seem that it actually is hot. I was thinking that maybe I have a bad thermostat, so I go to change out the thermostat and the lower bolt on the thermostat housing has been stripped out to just about nothing by the previous owner. I've tried just about everything short of drilling it out. I guess I have two questions here... What do y'all suggest I do with this stripped out bolt and where can I find a replacement bolt? and... Is there another reason my gauge would be reading hot when it is not running hot?





Thanks,

Karl

93' D250 Cummins Dually extended cab - Flat Bed

Karl,

Just did a quick study and it would appear that the bolt screws directly into the cylinder head. Is that the case????



If so is the damage only to the bolt or to the cylinder head itself??



If it is just the bolt maybe you can clean the threads up in the head and go with a new Cummins bolt.



Let us know what you are seeing.



Mike.

 

[DVolk]

On a anouther note a cheap socket cold be weled to the bolt and removed that way .



I think we need more info or some photos !!!!