Thermostat 160 or 140 in salt

[pyrotek]

I have 454 carb engine serial number 0K035983. Parts list is showing oem thermostat 807252T 2 which is a 160 degree thermostat. I am exclusively in salt water (Long Island Sound, CT). I don't know what is in there now (recently purchased). Existing engine temp seems to run about 130-160.

Should I purchase 160 or 140? It seems most websites are pushing the 160 type for my engine model. However, I have seen some people say 140 is better for salt, and I'm thinking with engine temps of 130-160, it may have a 140 in there.

I'm trying to fix a problem where the engine temp drifts from 130-160 and back within too short of a time ~30 seconds. I'm thinking sticking thermostat. Will also replace impellor.

Is Sierra or GLM ok to use?

Thx

 

[Pete104]

Re: Thermostat 160 or 140 in salt

Is OEM that much more?

Carbed engines run cooler, so 140 degree stat. EFI likes it warmer. Neither engine knows what kind of water it's in!

 

[pyrotek]

Re: Thermostat 160 or 140 in salt

No, I just need to order it online, verse get Sierra at NAPA which is easier.

I have read carb runs cooler, but I don't understand why this engine would originally come with 160 then? I know the engine wants to run hotter for efficiency, but in salt water the higher the temp the more salt buildup. So in affect, the engine indirectly does care about fresh water/salt water. Just not sure which is more important.

 

[Pete104]

Re: Thermostat 160 or 140 in salt

You didn't indicate whether or not you running a closed cooling system. They run warmer also!

Yes, it does care but doesn't know! No matter what, you have to keep the cooling system clean with fresh water!

 

[achris]

Re: Thermostat 160 or 140 in salt

Spec for your engine is 143....A year later they changed it to 160..

2 sides to this argument.

1. Run a cooler thermostat and the engine is not at the best temperature and could contribute to premature wear...
2. Too hot and the salt disassociates into acid, and engine blocks don't like that...

Chris.......

 

[pyrotek]

Re: Thermostat 160 or 140 in salt

Where do you see the spec is 143? perfprotech is showing 160 degree part number: 807252T 2

Raw water cooling.

 

[achris]

Re: Thermostat 160 or 140 in salt

Where do you see the spec is 143? perfprotech is showing 160 degree part number: 807252T 2

Raw water cooling.

Service manual #16, page 1B-4.

 

[pyrotek]

Re: Thermostat 160 or 140 in salt

Now that's strange. Later on it lists 143 for stainless steel housing.

Is there some kind of marking on the thermostat to know which temp rating it is? I guess I'll just have to remove it first before ordering.

 

[rickryder]

Re: Thermostat 160 or 140 in salt

Bottom of the T-stat on the heat sink it's stamped what temp range

 

[Josh P]

Re: Thermostat 160 or 140 in salt

yes remove the stat and look at the bottom they are usually stamped with the temp rating.

 

[pyrotek]

Re: Thermostat 160 or 140 in salt

Can anyone help me with the part number for the 143 degree thermostat? Can't seem to find a clear answer since every site says to use 160. I'm pretty convinced its the 143 degree thermostat based on the engine temp I have been seeing.

 

[achris]

Re: Thermostat 160 or 140 in salt

-807252t1