84 stock corvette - 160* thermostat

[muskiemike]

Hello,

I have read several posts about putting in a 160* thermostat to reduce the temperature . .. .

If you greatly reduce the engine temp, what happens to the heat of the engine oil, does not the engine oil need to get to 212* in order to burn off the internal moisture/water inside the engine?

I have a stock 350, with 30K miles and the original 195* thermostat.
Live in TX, so it does get hot, and am concerned about it.

I have read that many are experiencing great results by installing a 160* thermostat.

Comments please . . .

In advance, thanks!.

 

[JonM]

Duke....Your best bet to keep your 84 cool is install a Low Temperature Electric Cooling Fan SwitchWith the 84 you only need the 609-106. The harness is not needed, plugs right in with the old wire.

INSTRUCTIONS FOR INSTALL

 

[muskiemike]

JonM.

Thanks for your suggestion, I will check it out.

I think my 84 vet came with a low and high fan switch, which both settings are still working. However I am not sure at what temp(s) are used to engage either the low or high radiator fan?

 

[JonM]

JonM.

Thanks for your suggestion, I will check it out.

I think my 84 vet came with a low and high fan switch, which both settings are still working. However I am not sure at what temp(s) are used to engage either the low or high radiator fan?

That switch must be aftermarket, I never heard of a stock switch on an 84. The fans of an 84 come on at approximately 238 and shut off at about 201. That is why I suggested the other switch. Kicks fan on at 200 and off at 185. Works like a charm for me..also check that the front of the radiator between it and the condenser is clean. (is a major problem...corvettes are bottom feeders)

 

[muskiemike]

JonM,

I believe you are correct in your assessment: "The fans of an 84 come on at approximately 238 and shut off at about 201".

Therefore your suggestion of the other switch to come on at 200 and off at 185.

Now that makes sense. VERY good suggestion.

But if I puchase the new "609-106" switch, once I install that new switch on my stock 84, do I have to do anything else to get the fan to go on at 200 and off at 185?

 

[JonM]

Nope...not a thing. Just buy and install the 609-106...NOT the harness as I mentioned. And you are on your way to being :cool

JonM,

I believe you are correct in your assessment: "The fans of an 84 come on at approximately 238 and shut off at about 201".

Therefore your suggestion of the other switch to come on at 200 and off at 185.

Now that makes sense. VERY good suggestion.

But if I puchase the new "609-106" switch, once I install that new switch on my stock 84, do I have to do anything else to get the fan to go on at 200 and off at 185?

 

[Low drag - High speed]

I was having overheating trouble with my '84 and did several things to correct the problem. The problem was caused by a fan motor relay switch failing ... that's the little black box just in front of and below the brake bellows. Since I was on the case, I also replaced the fan switch, which is screwed into the lower part of the right cylinder head towards the back (behind the dipstick). Then I inspected my coolant and saw that it had too much rust in it and needed a thorough flush and new anti-freeze. A bench test of the fan motor proved it to be fine, so I saved a buck and didn't replace it.

Everything was fine after that and still is. In going through the troubleshooting and repair process, using the Helm Inc. factory manual as my bible and backed up by Hanes and Chilton ... I learned that, as you folks already noted, the proper fan operating temperatures are turning on at 238 and shutting off at 201 ... and it works exactly that way. I also found that the emissions controls are closely associated with the temperature range, as are timing, power and economy settings used by the ECM to modulate engine function. I considered a lower temp thermostat early on, but realized that I'd skew the balance and didn't want associated problems. And the car runs quite nicely now ....
On the other hand, if the cooler thermostat is a bona-fide factory part that gives you an option, I know that Texas heat can be a bear. I'm in Washington State where it doesn't get near as hot.

 

[muskiemike]

Jon,

on a 84 vet, is the temp switch on the head/block on the passeger side or on the drivers side?

 

[JonM]

Jon,

on a 84 vet, is the temp switch on the head/block on the passeger side or on the drivers side?

Pass side between plug 6 and 8

Read the INSTRUCTIONS FOR INSTALL ...gives you all the info.

 

[muskiemike]

Hey Jon,

I previously read the PDF instructions, it said behind the oil dipstick (Passenger side), but when I looked at that side in the garage, I could not see it, so I looked on the driver side, it there was some type of an insulator plug in the block, so I thought I would ask you.

I'll pull the car out into sunlight and take a closer look on the passenger side.

From what I read including your "prefessional" help, I think I am going to replace the 195* thermostat with a 180, and replace the original 238* electric fan switch with the 200* from mid-america, this should help considerably.

I decided to go with the 180* versus the 160* as I have a 4+3 manual (overdrive) and a previous poster side he installed the 160* and it was mistake as it screwed up his overdrive on the 4+3, and this might make sense, as the overdrive on the 4+3 will only engage when the engine gets to a certain temp.

 

[MoeJr]

I put a brand new temp sensor for the fan in my 84 and it comes on at 228. I am pretty sure if you look thru the forums archives you'll find that 228 is the temp it is supposed to switch the fan on.

Moe

:bar

 

[JonM]

Yes...its right next to the dipstick between the two rear most sparkplugs. ANd thats a BIG 10-4 with the relationship with the temp and the transmission. As the overdrive unit gets information from the ECM. Too cool and it will slip in and out of overdrive.

Hey Jon,

I previously read the PDF instructions, it said behind the oil dipstick (Passenger side), but when I looked at that side in the garage, I could not see it, so I looked on the driver side, it there was some type of an insulator plug in the block, so I thought I would ask you.

I'll pull the car out into sunlight and take a closer look on the passenger side.

From what I read including your "prefessional" help, I think I am going to replace the 195* thermostat with a 180, and replace the original 238* electric fan switch with the 200* from mid-america, this should help considerably.

I decided to go with the 180* versus the 160* as I have a 4+3 manual (overdrive) and a previous poster side he installed the 160* and it was mistake as it screwed up his overdrive on the 4+3, and this might make sense, as the overdrive on the 4+3 will only engage when the engine gets to a certain temp.

 

[geekinavette]

Just FYI Mike...there IS indeed a sensor in the driver's side head as well...that one is for the cluster temperature gauge. The fan temp switch should be in the passenger's side head between cyl 6 and 8.

Bill

 

[lagasvd]

Just because you install a lower temp thermostat doesn't mean your engine will run cooler. If you are currently running temps above your present thermostat setting it will continue to run that hot. The lower temp thermostat will only open at a lower temperature and the only thing it will accomplish is taking a slightly longer time to reach the current temperature. I'd recommend sticking with the current thermostat, checking the fan situation out and replacing the fan switch with a lower range on and off, change coolant yearly, and make sure you clean out the junk accumulated on the radiator.

 

[tigmaned]

yeah the crap that gets between the RAD and condsenor is something!! our fronts our like kriby vacuums!! i checked between mine and i had a few inchs deep off S--T in there. but mine never runs hot, the last guy must have done the lower temp fan switch, mine runs at 185 almost all of the time, but i do have a RAD only 7 or 8 months old. feel around your rad and see if you have any cold spot when the engine is some what hot, could have bad areas in side from age and corrison.

 

[muskiemike]

Gents,

Thanks to you all for your comments and suggestions - looks like I am ready to get my hands dirty on a nice upcoming fall day here in Dallas.

Again, thanks Gentlemen . . . and Ladies too if applicable.