projectheaven

Hello all. My buddy has a 70 442 that he's starting to finally put money into.He has a problem. I think.When he drives the car the temp climbs as if it wants to get hot.When he parks it the upper radiator hose is as hard as a rock from pressure.He has to release the pressure by pushing up a handle on the metal raditor cap.
What do you think the problem is?

Olds64

Has the coolant system been serviced recently? You want to make sure everything is in good shape and that the protection level of your antifreeze is adequate. That is at least an easy starting point.

branchman88

Hey man, I been seeing you all over youtube and all that...lol. But look man got a question...why u got two different sets of wheels?

projectheaven

Because I got tired of the same set being on there.I was trying someting new and decided to keep it that way.Who knows...I may just go back to the rallies again.

shaks 442 clone

the upper radiator hose is supposed to be hard for awhile after driving thats a good sign that the cooling system is being pressurized.

you could take the thermostat out and stick it in some boiling water and see if it opens

projectheaven

He wasnt using a thermostat.I think he's going to install one this weekend though and a new water pump.

The_Jeremiah

your engine will get really hot if the timing or mixture is off. Might want to check those

goodkarmech

What's been said above re - pressurized hose, antifreeze, thermostats all good.
May have a clogged radiator. If all else is exhausted, remove it and have it flow tested. Suspect the radiator especially if the coolant is rusty and there are deposits inside. Also a bad fan clutch will cause overheating in traffic, but not out on the road. If you are gradually getting hotter and hotter out on the road, then a clogged radiator is the most likely suspect after a defective thermostat or slipping water pump belt(s). I've also seen cooling systems act up when no thermostat is installed, and I've seen new thermostats be no good out of the box.
I suggest you invest in an infrared temp gun for 50 -60 bucks. With most of these cars, there is just the hot light, and no temp gauge, so if you really want to know how hot the engine is you need one of those, or a thermometer stuck in the coolant somehow...Nice thing about the infrared is you can check the temp of different parts of the cooling system with it ie upper hose vs lower hose, different parts of the radiator, cylinder head temp, water outlet temp etc...
There is one other cause of coolant temp rising, and that is a leak from the combustion chamber into the cooling system. If the engine does not run smoothly, puts out a lot of condensation in the exhaust and has any kind of sweet exhaust small, suspect a problem in either a bad head gasket or a cracked cylinder head. To check that, there is a tester kit made with fluid that changes color.
Good luck!!

Pghstarsky

with that heater gun, while I'm pointing at my rad. what temp should it be?

don71

There is no published data that I know of. Maybe a student of thermal dynamics could do the math......The temp of the radiator will be different in places and should be cooler -slightly- than whats in the engine. But it depends where you record the temp. You should know the temp if you are using mounted guages in the car. But it only reads at the intake manifold though.

With that said, you can make a log and start recording data. Compared over different conditions and many months could be helpful . I have that tool, but don't go **** retentive with it. Too much info can be a bad thing but its fun pointing it at everything under the sun

Goodcarmech kinda summed it up.....maybe projectheavens friend will find his problem after a new pump thermostat. Its that.... or the rad is clogged.

goodkarmech

Using the infrared is not an exact science, but I'll try to share with everyone what I have learned while using one on various cars. In a car with the cooling system operating well, I find the coolant to be the hottest at the cylinder heads and front of the intake crossover where the thermostat is. Next the coolant flows out the upper radiator hose to the radiator, so the coolant is hottest in the radiator, near the upper hose inlet. By the time it is going back into the engine at the lower hose it is usually 30 -60 degrees cooler depending on ambient temps. Thus, the coolest temps will be at the lower hose and the water pump connection to the lower hose. If it is a really hot day, there may only be a 20 degree temp difference between radiator inlet and outlet temps.
If you are running a 195 degree thermostat, expect to see 195-210 degrees at the upper thermostat housing, possibly approaching 220. If the thermostat is operating right, then as the car warms up, the thermostat housing will approach the operating temp while the upper hose and radiator remain around ambient temp. Then when the opening happens, the radiator will get hot. If you find the radiator warming up as the engine does, suspect a partially stuck open thermostat. If the engine is getting really hot ie 230 -240 and the radiator is still around ambient temp or way cooler than engine temp, suspect a blockage in the flow ie stuck closed thermostat or clogged radiator. The car will probably not be driveable if this is the case. If you follow each row of tubes across the radiator using the infrared, you should see gradually reducing temps from the hot side to the colder side. If you find there is not much temp drop across the radiator ie 5-10 degrees then you may have a clogged radiator. In the same sense, if you follow the tubes across and suddenly the temp drops off in one area more than in another, that particular tube may be clogged around the point of temp drop off. Keep in mind the infrared is not always exact, and different surfaces and colors of material yield different readings on the tool. Usually each instrument will have instructions that tell the characteristics of the particular instrument.
Other things I have used an infrared for are:
Measuring exhaust header temps to find a cylinder misfire.
Checking catalytic converters, they should have a hotter outlet temp than inlet temp (20-40 degrees usually, or 10% - 20% increase)
Checking for a hot brake drum to identify a dragging brake.
Setting the on temperature, for an adjustable electric fan switch.
Checking A/C system temps.
As Don71 said, it is fun to point it at various things an check their temps.
Hope this helps some folks on the forum.

Oldsguy

good information, good thread guys.

projectheaven

Great info! I just got back into town so I'll pass this info on to my buddy.I'll definitely let you know what's going on!

palmers65

Check the thermostat and flush the system how does the coolant look? is it clean? Flushing the system will make sure it isn't plugged up somewhere. If this has been tried then let me know.

projectheaven

Hello guys! Something new I noticed when we took his car to Kragens auto store.When we got back in his car to start it up it cranked over real slow beofre it finally started.It also took about 5-10 seconds before it finally fired.Could that have something to do with the timing of the car?