How to remove Thermostat on 1987 4.3 OMC Cobra?

[EVoskani]

I am in the process of rebuilding my 1987 4.3 OMC Cobra engine and decided to replace the cooling thermostat on the engine. However, I can't remove it from the housing, is this pressed in? What's the right way of removing the thermostat? Please advise, thanks.

 

[boatermarquis]

should be the same as a 5.7 350,we had one that wa stuck also,we pulled a hard as we could to get it out,thats just a tip,i think we even pried i there,i may not be right,but thats how we got ours out.

 

[MRS]

I might be wrong but if I remember right it is only a o-ring that holds it in. Remove o-ring should be able to pull out clean up housing and replace.

 

[boatermarquis]

wonder if he put little grease around it,maybe it will come out easier next time,

 

[Bayou Dave]

Taker something sharp and go around the outer edge loosening any rust. Vacuum up any loose rust. Then pry it out or grab it with some pliers and yank it out.

 

[shades251]

Yep almost every single thermostat made just pulls out. They corrode in so it takes some force. And I don't think I would put grease to make next time easier. I would not want the grease in the cooling system.

 

[Scott Danforth]

vice grips, grab the t-stat and pull it out. you will mash up the t-stat.

then get a 1" wire cup brush and clean out the rust

then put in the new thermostat.

 

[MRS]

Pull it off and soak the heck out of it with liquid wrench I remember that is what I did....

 

[jbetzelb]

Mine is a 89 but there is an rubber ring that needs to come out then the thermostat comes out pretty easy. I had to soak mine with WD40 to remove enough rust to even see the rubber ring. I say rubber ring because it is round but it isn't a O, it is square.

 

[bruceb58]

Yes, rubber o-ring holds it in place. Don't yank it out like people are saying or you will ruin it.Get the o-ring off first.

 

[MRS]

bruce, is right when I said pull it off and soak with liquid wrench I mean't the housing then remove the o-ring then soak some more. If you mess up the housing you will have to find a used one and they are not cheap.

 

[Lou C]

I use a pick or a very small screwdriver to pry that rubber ring out. They get camouflaged by rust over time.