can anyone please tell me if the 195 degree thermostat is the correct o.e. thermostat for the 454 chevy? also, while we're at it, does anyone have any experience with water wetter[tm], and does it do anything at all to make an engine like this run cooler?... thank you. tred.
Define correct ... I believe a lot of 454 engine originally came with the 195 thermostat. I bought a new 454 - 450 LS-6 crate engine in 1970 but I forget which thermostat it came with. I ran a 180 in mine ... Opinions will vary greatly on this subject of thermostats ... Never used water wetter ... NEVER needed it
ahh... my apologies D.R. i live in the desert of lost wages, and i am having overheating/running hot issues. on a 95 - 100 degree day, the 454 is running at 220 plus degrees, and if i have to sit in traffic for very long, i'm done, car will overheat, not to mention those summer months where the air temperature here is 120 plus, i don't think i could cruise around the block without overheating. i realize i can have a three core radiator made from scratch by a guy here in town, but not having the cash it takes on hand, i thought i would try the inexpensive solutions first and see how it goes. i'm running a 180 degree thermostat now, i found sources online that say this thermostat is an "alternate temperature" unit, and lead me to believe that i should run a 195. i guess i should have asked for advice with overheating issues really. anyadvice on this topic will be heeded and APPRECIATED, i don't want to park the car until i can have a radiator made. help(?)...
Just messing with you ... Some purists will say you should not change anything ... I have found, in my experiences, here in the South where it gets pretty warm also ... that a 195 can actually help the engine run cooler. The 195, in certain situations, holds the coolant in the radiator longer and allows the radiator to cool the coolant down before it leaves the radiator to return to the engine. I had a 1970 LS - 6 Chevelle also, and it originally came with a LARGE 7 blade clutch fan. Mine also had a 4 core radiator ... from the factory. AND a shroud ... Try the 195 ... it is only a few dollars. I also drill two small 1/16th holes in the thermostat ... to allow all air and such to purge. BUT ... I believe you need to save up your nickels and dimes for a radiator ... and soon
Deuce Roadster's comment about the two 1/16" holes to allow air to bleed out of the cooling system is right on the money. I drill one 1/8" hole, but it's close to what DR does. I did try two 1/8" holes, but it's too much. Takes about 4 miles to get up to operating temp in my roadster in 16 degree F weather and only 1 mile with one hole drilled. Looking from here, if your overheating is happening in traffic it may be caused by the vacuum advance unit being sourced to ported vacuum. It should be sourced to manifold vacuum. Reason being, it takes time to burn the lean idle mixture and GM engines require quite a bit of additional advance at idle. If you don't have a vacuum advance distributor, get one. There's a good reason factories use them. Race-O (no vacuum can) distributors belong on the race track.
more good advice, thank you. what should i know about radiator caps? mine's a 16 lb. cap, is there another "problem" running this or is that pressure ok for my situation?... thanks again guys.
the higher the pressure of the cap, the higher the boiling point of the coolant. also with old radiators the higher the likelyhood you'll blow up the top tank. The thing about big blocks in the southwest is that you need a bigass radiator, and a bigass fan driven by the engine and well shrouded. the blown 454 in my 55 hasn't boiled over in vegas in the summer when I've been there, but it has the biggest radiator Chevy ever put in a car (early-mid 70s full size car big block radiator) and a big clutch fan and shroud. on the thermostat....180 should work fine, 195 should work fine, they generally came with 195 to keep emissions down and fuel economy up.
Squirrel's right about the high press cap. I ran a 16# in my 32 roadster and the fairly new Walker radiator split a seam at the top. Radiator shop guy recommended I run a 7# cap because the tall and narrow old style radiators tended to split a seam under high pressure. Makes sense, but the engine hadn't really gotten too hot up to that point so I'm thinking the radiator had a flawed solder joint. The radiator's been great ever since - had it since 1985, on the road since 1993. Fwiw, the 16# cap takes you to 257 degrees before boilover and the 7# cap takes you to about 234 degrees before boilover. Not a problem for me because I'm shutting the engine down when the temp gets to 220 degrees. Seems like thermal runaway - in older cars - takes place at that point. Anti Freeze will raise the boiling point, but an overly high ratio of anti-freeze to water won't cool as well as straight water. I've done well with straight water and a water pump lube (water soluble oil - Prestone makes a good one, small yellow plastic bottle in the anti freeze, radiator flush section of the store). What kind of car are you running?
Are you fully shrouded? Shrouds tend to be cheap and time consuming. And massively helpful for low speed overheating. Perhaps a good fit for the situation.
I've played a little bit with wierd coolants, but I always seem to go back to good old prestone type antifreeze mixed 50-50. How hot is too hot? boiling over is too hot, and over 240 is too hot, but the 220-240 range is iffy....if the temp takes off every time it gets to 220, then shutting it off at 220 is a good idea. But it seems to me that is just an indication that the cooling system is way undersized for the engine.
running a 180 with one small hole in mine, with a 16lb cap... runs for hundreds of miles at a time never getting over 205 degrees... and Kansas gets hot too. I do change the cap and thermo every year or so when I flush the radiator... but I'm anal about such shit. never hurts. Flushed lately? you might have crap in there you are unaware of. I had a weird instance one time with a peice of sealant stuck in my stat - holding it open... took me forever to figure that one out. (hi squirrel )
hey greg if you're talking about the Suburban, that thing has a radiator that's bigger than Jay's whole car
well, i've got a brand new aluminum radiator (but it's a two-core), a seven blade fan, and a big shroud. all of this is stuffed into a '51 chevy sport coupe;
Or . . . in my case, a flathead on a hot Santa Barbara day. I didn't know one head could dump that much water . . . sorta like Niagara Falls it was. Seen the thermal runaway bit on an SBC that was towing a load as well as on a Ford 400-M in a 77 3/4 ton 4x4. We made the summit on the long desert grade with the SBC powered pickup before it got too bad and cooled down headed downhill on the other side. The Ford had to be parked for an hour or so until it cooled down and the sun went down on a warm SoCal October day. Last move from SoCal to Central California in 1988. I left some stuff behind - good welding steel etc. - to make sure the double axle trailer wasn't overloaded. Unbeknownst to me, Sweetie was piling rocks into the back of the trailer when I wasn't looking. She couldn't bear to leave her garden rock collection behind. Probably only 300# or so, but it didn't help....
go get some purple ice in the mean time too...i've seen it lower the temp, with nothing changed mind you, as much as 30 degrees. i sell a TON of it at work. hell, with that and the thermostat tricks you've been given you might not even need to upgrade the cooling system.
that radiator looks kind of small! (seriously) also it might help some to seal up the outer edge of the radiator to the inner fenders and hood to make sure air doesn't go around it. what kind of fan does it have?
Sounds to me like an airflow problem. How tight is it around the engine to the firewall and inner fenders? The radiator needs a way to get the air out from behind it. Have you treid it without the hood, to release air from behind the radiator? jerry
Air Flow very important, Purple Ice didn't help me. I run a 180 thermostat and temp stays @ 190. 1970's 3row radiator with a puller fan in a 70's 454. Take Care
SB's here, but I ran 160 w/ two 3/16" holes in it's rim to help burp her! It and my stock clutch t/stat deal and I want to say 6 or 7 bladed rigid fan. I could throw a belt on my old junk301 and drive 15 miles home b/c the air coming through the rad would turn the fan and water pump! pdq67
Are you using an aftermarket "flexy-flyer" fan? They can be less efficient at lower speeds and a stock style blade could likely move more air. If the fan has a clutch on it, it might not be working properly. You might try removing the clutch, running the fan directly and maybe adding a spacer to move it closer to the radiator if it's more than a couple inches back.
I've been struggling with one of my 440's its running 210+ since it got hot above 90. It will sit and idle at 180-185 but gets hot when driving out. Its got a cheap chinese radiator that I hope tomorrow will be gone. I've been thinking about my clutch fan your BB and mine use the same one. It seems to get spastic on the highway up and then down. I can raise/race the idle up and the temp will drop some. I run a 19lb cap which gives me a few degrees to play with. I had an old time chrysler tech tell me the wisdom of getting the old EGR working again, at 20 degree engine temp drop for one. I just got a new 180 thermostat today to put in. One theory was to cut back on the 50/50 antifreeze mix as more water will allow the marginal radiator to cool a bit better. I ran a 6 hr ride back from the Chrysler Nats and was baking the whole way home. Imagine if my a/c was working. Good luck I aim to master my problem.
I've been researching this issue also. I found quite a bit of info searching "fan shroud", radiator shroud" and similar. It's hard to tell much about your shroud, but what I see is that it looks like the air can go around your radiator rather than through it and you also have to make sure that air can get out of the engine compartment. That's all I got. Brett
Im running an old 283 with a 4 row radiator, 180 stat with a mechanical fan that sits 6 inches from the rad (no shroud). It never gets above 210. Even in traffic on 100+ degree days. Im using Evans coolant and I swear by it. Expensive but worth it. Look em up...
I am sure that this thread is WAY over....but I want to throw my 2cents in.... Have a fresh 454 that runs at 190 on the open road with a 190 thermostat.....if I got into traffic or lights it would jump to 220-230 and have a hard time cooling down..... after a new aluminum radiator and checking the thermostat it did not solve the issue.... Am running a Holley 750...............stock jets (70's)............put in larger jets (86's) and immediately the engine did not climb above 190 in traffic even with A/C on....... basically I was leaning out the engine and causing it to get hot. Hope this helps somebody. -Dogger
Running one a little fat helps cooling but its a balancing act as I am sure you have found out. Another thing that helps cool one off is letting some of the hot air out. In a car with a closed engine bay ambient heat is also an enemy of cool running. Louvers help that a ton, they are for more then looks.
Remember the overheating rule of thumb. Runs hot at highway speed - not enough radiator. Runs hot at low speed - not enough fan. I'd save my money on Snake Oil like water wetter. A properly designed cooling system will cool just fine with 50/50 mixture of anti freeze and water. A thermostats temperature setting has nothing to do with your problem. With the temperature your running they all should be wide open. Gary
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