Broken Thermostat Housing Bolt. Now What?

[emac]

Isnt it still hot!!! Only a master can do that and not get burned. Glad you got it out.

 

[orangefj45]

Worked perfect on all 3 broken bolts. Thermostat housing was then bead blasted, sensors re-installed and the whole assembly is back on the cylinder head. Let the sealant set up during lunch break. Then added coolant, pulled it out of the shop and let it come up to temp.
Then back in the shop later this afternoon since the knuckles and TREs need some attention ......
More pics to come.

Georg @ Valley Hybrids & Cruiser Brothers

 

[Racer65]

You da man !!

 

[fhawk5]

You know, I had the same thing happen, and I realized the coolant running through the metals was creating an issue. I will not be long winded , but , here is what is happening to the housing.. Remember, housing and enging are dissimilar metals.

 

[orangefj45]

Yup. Lots of electrolysis happening there.
Cast iron head
Steel bolt
Aluminum thermostat housing
Coolant

Recipe for corrosion!!!!

Georg @ Valley Hybrids & Cruiser Brothers

 

[Racer65]

Isnt it still hot!!! Only a master can do that and not get burned. Glad you got it out.

Not only that, notice the proximity of the valve cover gasket to where he applied heat.

 

[shipmag]

This process is common bolt failure due to corrosion all over these rigs. One has to learn if Kroll wont make it loose heat it with a torch just to red hot (this is the learning process) without melting the metal. If it wont unscrew with a short wrench I heat them.

 

[Pin_Head]

Welding gets them out because after you heat steel over 1400 F to weld it, it shrinks when it cools. The castings TIG weld real nice with 4043 filler in case you have one break off a tab.

 

[KingAir Driver]

hmm.. common you say.. As I was trying to get mine off tonight after soaking they wouldn't turn at all! The bolts into the head came out cleanly, but now I have a housing stuck together.

 

[Weber Sarge]

Just fyi - if you want sealant that requires no wait time - use The Right Stuff , black flavor . Basically , liquid rubber gasket in a pressurized can - works awesome . I've installed water pumps with no gasket and fired the engine right up when it's back together , never leaks . Works great on oil pans too , just use sparingly or whatever you glue with is no fun taking off later - seen guys break cast oil pans trying to crack it loose .
New engines are assembled with this stuff now from the factory , btw .

Sarge