After two years in paint jail we went to get my buddies car out of the shop. The car has not been ran in well over one year. Engine is a 347ford with dual quad set up mated to a toploader Mechanical fan and griffen aluminum rad. He had installed a 160 thermostat prior to dropping it off for paint. The cap on the rad is 13psi. NYC was about 90 degrees yesterday and we got slammed in some bad traffic after beating on the car some. The temp gauge never rose past 180 but who knows if thats accurate. Coolants puked bad from the overflow tank and we barely made it to his house. I am wondering if we need to change his rad cap to a higher psi rating but whats the theory on finding the best one without overdoing the rating? Everything on the engine is brand new so no gaskets or waterpump issues at all. I think the heat really was a wake up call to get this sorted.
Puking does not automatically mean overheating. The first thing you need to determine is exactly how hot the coolant is getting in that motor either with a heat gun or a known good temperature gauge. You say the gauge never went beyond 180 but that you barely made it home. What was the car doing that caused you alarm ? Did it act way overheated when you finally shut it off ? Don
Yeah engine ran horrible, stumbled a bit and def acted like it overheated. We lost alot of coolant in the process the more we drove the more puked out as we saw the steam between hood and fender. I doubt the gauge is right but who knows. Fyi cars filled with 50/50 prestone and water. When we got to his garage and shut it down it puked well almost a gallon all over the floor
Pull out the thermostat as a test, refill the coolant, and try it again. The thermostat might have been stuck from sitting that long. Check the lower hose for collapsing too. Don
Actually it shouldn't over heat with a 180-190 thermostat in it, muchless a 160. 160 actually is colder than should be run. Cyl wall wear is 3 times higher with a 160 vs 180. Is your radiator big enough for the engine? fan adequate? fan shroud? sheet metal in place to direct air through the radiator instead of allowing it to go around it?
If everything in the motor is brand new , should you have been "beating on it"? It could easily be a blown head gasket if all is brand new and the thing hasn't been run in.... has the heads been retorqued since the motor was rebuilt? If the painter has been moving it around it may have been through numerous hot cold cycles.... Back to basics for me is always a compression test before anything else when there is an engine problem. If it has puked enough water out, that the temp sensor is not covered with water it will not be reading water temp at all , just air/steam temp in the block. Other things to think about, old ****py gas, air leaks, retarded timing.
After sitting for a year dormant, I would have replaced hoses, belts, thermostat, coolant and cap. Also, fuel filter, air cleaner, drain and replace gas.Those are all fairly cheap to do and they are prone to deteriorate over time. It amazes me that folks will just toss a battery in a car that's been sitting and expect everything to be fine.
Yep, back to basics. Can't stress that enough. Also a side note - a 50/50 mix protects from freezing down to -58* at a cost of 30% reduction in the coolants ability to shed heat when it's HOT outside. A 50/50 mix is mostly so the coolant retains the heat and doesn't freeze. When temps are in the 90s there little chance for a cold snap to -58 without warning. But if there were we'd have bigger troubles than frozen engines. Straight water is much more efficient at cooling but there's no corrosion protection or pump lubricants, a 25/75 mix provides enough of both and sheds heat at only a 10% reduction. Bottom line here is just changing your coolant mixture gets you 20% better cooling system.
Thermostat value (160°; 180°) does not control the temperature at which the engine will run. All the thermostat does is open at a designated temperature and allow the coolant to begin to circulate which allows the optimum warming of the engine, depending on ambient temperature. Once the coolant is flowing, the thermostat is out of the picture. It's a valve - opens & closes, nothing more.
There's a bit more to thermostats than that. Just like any equation there's 2 sides - the radiator and cooling system's ability and rate to shed heat against the engines ability and rate to generate heat. Ideally the cooling system will loose heat faster than the engine can make it, in this case the thermostat will maintain the engine temperature at a consistent and reliable level. If the situation is opposite and the engine makes more heat than can be shed by the cooling system - even by as little as 1% , the thermostat will remain open, temps continually climb and eventually the engine will over heat.
They usually end up at an equilibrium, since the higher the temperature difference between the radiator and the ambient air, the more heat it will shed. But if that equilibrium is higher than the boiling point of the coolant, then you have a problem. NO pictures? we can't see if that nice Griffin radiator is way undersized? or how the fan system is set up? we don't know if the coolant was the the correct level before the drive? Way too many questions to get a useful answer at this point
I would go for 180 tstat and 16lbs. my Bonneville had a 160 in it and once it reached 160 it never cooled off, it got hotter and hotter. it depends on what the motor is designed to run at. most engines that size use 180. the 13 lb cap is probably the reason for the puking. get yourself a good working temp gauge. to me its the most important gauge to have correct Posted using the Full Custom H.A.M.B. App!
i have a 331 stroked 302 with a 180 stat and mechanical fan. car never gets past 185 on the hottest days in traffic. I never liked running 160 stats, temp always fluctuated to much.
I had a bad overheating problem with a Griffin radiator in my '40 Ford convertible and after many sleepless nights and changing everything from the pulleys to radiator cap to flushing the system and nothing helped. I was fortunate that I lived close to Griffin Radiator when they were located in Townville,South Carolina when it was owned by Buddy Griffin. After 2 years fighting the overheating problem I got in touch with Buddy and he told me drive the car to their facility and let them take a look. Less than 5 minutes running the car at idle at their shop it started running hot. ,he decided I should pull the radiator and bring it back to the shop. 2 days later I walked in and met Buddy's shop foreman at the time and he and Buddy had decided to make me a new radiator but not until he cut the top and bottom tanks from the core,,so up on a huge band saw and he cut the radiator core slightly about the tanks. What we found was more than half of the cooling tubes were compromised with the sealer that bonds the aluminum..this is supposedly something they don't do any longer. After I got the new radiator I never had a problem again. As someone mentioned earlier,photos of how everything is set up would help. HRP
Another though,you said a mechanical fan,is it one of those cheap flex fans with aluminum blades? They are unsafe & basically effective in keeping a engine cool. HRP
Like many others, I think your problem is more than thermostat. Check ignition timing, head gaskets, fresh gas, Lean carbs etc. Good luck!
Ok we checked th thermostat it works fine and we filled up with more coolant and purged the system and drove the car for an hour. The temp gauge never went past 170 No more overflow this time around and he got his ir thermometer and the radiator when we got back to his place was 148f the hoses were 156 and the engine itself around 130-170 Yes the car also has a flex fan he does plan to install a dual electric fan but he just got the car back so he has alot of work to do still finishing it up He showed me the thermostat that came with the engine and it is rated ag 192 no idea why he installed a 160 instead. Engine also has the high flow edelbrock water pump
You really don't need a electric fan just get a quality steal blade fan. This is what I used on all 3 of my current cars. HRP
For me the first thing to do is find out exactly how hot the engine is running. Guessing is not diagnosing. An infrared thermometer or a different known to be good gauge... It sounds like you have an airflow problem when it heats up in traffic. This should occur in the garage too. You can get the cap tested easily. I'd go with a 180* stat You never said how old the installation is? Was it sorted out prior to sitting or is this essentially it's maiden voyage? After finally getting painted? Electric fans are band aids for poor/lazy mechanics. Pictures are nice because we can see how far the fan is from the core and if any shrouding would help. I looked again and I cant find what type of car we are concerned about. To me 347CI means it's over sized something. I wrote all this before your latest posting. It sounds to me like it is running too cool for long life. Still would be nice to know what kind of car and any pictures of the installation.
I just went through the same thing as HRP. The car had sat since last fall and when we put the new engine in it overheated like crazy. We just KNEW it couldn't be the nice Howe aluminum radiator so we replaced the pump,changed the timing, added a nice fan shroud,changed caps ect ect. For the heck of it we took the radiator to have it flow checked and it was plugged half-way up. New radiator fixed it.
One source is...that running a 160 in late model Mustangs was supposedly tricking the computer in giving it more gas, or something, that was supposed to improve times on the strip. Never played with them so don't know.
I completely agree, but my point was that once the thermostat is open, be it at 160°; 180° or whatever, the coolant flow will be the same. If the cooling system is unable to shed the heat produced by the engine, the thermostat rating will NOT make the engine any cooler or warmer. Once it's open, it's open, regardless of the opening temperature.
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