hey i was hopeing u guys can give me some info. today was really hot about 36 deg and i was on the highway cruseing at around 3300RPM for about 30 min then on the road for another 25min. when i shut her down to get some water i hear a whistle from under hood, so i pop the hood and my coolent bottle is overflowing and boiling, i lost about half the bottle. so i wated for an hour to cool down and went home. i have all aftermarket gauges and the temp gauge broke on me so i dont no the temp (thank *** i stoped when i did! or oh no!)
anyway i have a TH350 3 speed tranny with 3.42 gears and need to know if this is a normal thing to happen or is there something wrong with my car?? what RPM is a safe speed on the highway to cruse?what is to much? can u guys please help on this???

 

Not normal. Unless you were really beating on it and then shut it down hot, you shouldn't get boil-over. Is it getting hot in your area lately? If you got a marginal cooling system you'll probably find out on the first hot day of the year.

3300 isn't too much for a small block Chevy on the highway. Your ears might get tired of the engine screaming at that RPM after a while but it shouldn't cause problems or overheat the engine.

 

Is the coolant/water mix right? Coolant expands alot more than water, so if there is too much, it might boil over like that.

Did your fan turn on? Hows your belts looking?

 

Also, is your air dam still there?

No hoses collapsing on you?

 

3300 sounds a little high to me, but then again , you are running a 3 speed tranny. Maybe you could post this in the tranny section and ask someone about what rpm you should be running on the highway. It sounds like you have a cooling problem. Check or change the thermo, hoses etc. I assume you have a mechanical fan? If not, your temp sensor could be shot. If electric fan then you could rig it to come on when you turn on the car. Check the fan fuse if you have one and all the connections etc.

 

That's about 70 mph or there abouts... I used to cruise at 65 mph taching 3,000 rpm with 3.42's. Anything above 65 for me, the engine would run a bit hotter but slowing down again it would cool off just fine.

 

I have a TH-350 with 3.73 gears. @ 60mph its @ 3000rpm, 80mph = 4000rpm 1000mph =5000rpm. My car does fine not overheating problems or even higher temps.

 

Did the coolant smell like *** when it was purging out?

 

That's quick!

Does your engine over heat when you normally drive around? I'd assume not but... Check to see if there is anything blocking the radiator. I know trash and leaves like to collect around the bottom of the radiator.

 

Is there a reason no one has said blown head gasket?

 

Probably because a blown hg is pretty obvious. If he had one.

 

Don't forget to check the radiator cap. With out pressure on the system, the water/coolant mix will boil at a lower temp.

 

no i was not beating on her i was moveing with traffic (i really miss the OD lol) and yes this is the first time this ever happend, everything was fine after i let it kool down and today was just as hot and i didnt have a problem driveing around town. no i didnt notice any smell, and yes i do have a mechanical fan, i dont have a blown head gasket and i still have the airdam, and from what i can tell there is no broken lines anywere but i will do a full check on that tomorrow to make sure theres no small leaks or something. i buy the pre mixed antifreeze so it should mixed perfect, but the coolent that was in there at the time was old and dirty so i drained that and filled it up with new pre mixed antifreeze today. the hose the runs from my intake to the rad is a bit weak but i dont see how that could be the problem. the rad on the other hand might be it came from a 305 and is smaller than what i should have, i have to use 2 of those rubber things at the top that fit in the shroud to hold is from moveing around otherwise the rad wont touch the shroud and moves all over<<<example of how small it is if u get it lol)), could the rad be to small?? so what do u think now?? oh and another thing i noticed was that the car was alot slower before it boiled over.

 

The 305 radiator isn't a problem. There are people who use those with 400" and bigger engines and don't have any problems.

Check the rad cap and make sure its tightened properly.

Oh, what kinda thermostat do you have? If its not the 'fail safe' kind, then it may have locked shut, and that could be the problem.

 

I had that happen to me before on the way up to school. It's a 2 hour drive on the freeway at about 3200 RPM. I had to sit in a traffic jam for about 45 minutes so that didn't help either.

Right before I left, I checked all my fluids and my coolant looked low so I topped it off with just straight antifree (no water). I think I must've filled it too much and it expanded out. It was completely fine after that. I would advise getting a new guage or fixing the old one. That is one of your most important guages.

Steve

 

k so the rad is scratched off the list. oh i 4 got to mention on the way home for about 15min it was moveing really slow if that makes any diffrence in the cause. i dont know what thermostat i have it came with the engine, i will get a new one tomorrow just to make sure. ya i am not going to go on the highway till i get the auto meter gauge i ordered it should be here any time now (i hope) anyother idea??

 

lol!

That when you flux capacitor charges up, i hit hyperboost and my tranny shifts into warpdrive.

 

1. Go to Pepboys and ask for a flux capacitor
2. Watch them scramble looking for it
3. They'll ask if you mean a catylitic converter
4.
5. Profit

 

Make sure the fan clutch is working/ not leaking...mix your own 60/40 distilled/anti ... you want to check the bottom hose...


4. While the parts dolts are diverted quickly take over their terminal and find the crap you need in half the time.

 

They really are idiots there. I went to Pepboys for pads for an '02 Lancer, no one else around had them. The guy in parts said $45. I said I have a wholesale account with them for the place I'm coming from and I'd like to know the wholesale price. He asked if I meant the price after taxes......

 

Water is a much better coolant then antifreeze. It is better to run a 20/80 mix antifreeze/ distilled H20. In fact people on this board are running straight water with a little "water wetter" for lubrication and corrosion resistance. This is the best method of cooling for cars that have heating issues and high performance engines that make lots of heat.

 

That was supposed to say distilled/anti. I gotta fix that. I usually say 60/40 b/c many people forget to change it out and it offers deceent cold weather protection as well. Personally I wouldn't go under 60/40, but I'd add something like water wetter to it.