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baadgoat65 07-09-2010 07:52 PM

389 overheating
i have 65 389 with a tripower engine gets hot after running a wile reset timeing , carbs, new fan , new high flow waterpump, 3rd thermastat , new shroud, new 4 core radeator , have antifreeze mixture at 50/50 and have added water wetter and was checked for blown headgasket it was ok i can drive the car about 1/2 hr to 45 min before it gets to aroung 205 and then it just takes off and starts to lose engine vacumn and the power brakes start to fail does anyone have any ideas anything thanks :(

WDCreech 07-09-2010 08:57 PM

I'm just grasping at straws, here, but do you happen to have a water pump with the stamped impeller? If so, that may be your problem. Other than that, I don't know.

baadgoat65 07-10-2010 08:37 AM

hot 389
hi thanks for replying to my post i do not have the stamped impeller i knew obout the problems with them before i got the new one could i have a head gascket leaking that would not show on the haed gascket test i do not loose any antifreeze what do you think of wrong head gasckets i had the moter rebuilt at a co called engine remanufactureing in illinoise if you have ever heard of them well anything you can think of will be helpfull and thank you guys for answering my post

ericnova72 07-10-2010 08:47 AM

What condition are the two rubber grommets and the seperator plate behind the water pump in?? Known problem area for aged Pontiacs.

baadgoat65 07-10-2010 08:51 AM

hot 389
hi it is a 65 the one that has the set of 2 divider plates that doesnt use the rubber seals i even put new plates in i just dont have anymore ideas thanks for your reply

sqzbox 07-10-2010 09:42 AM

Q #1 What's with the loss of vacuum? I've never heard of that with over heating.
Q#2 Was the re-manufacturer SRC in springfield?

Might want to check the condition of the lower rad. hose. If it even partially collapses after warm up especially with a high volume water pump cooling efficiency will be compromised. :eek:

baadgoat65 07-10-2010 10:42 AM

hot 389
hi i dont know why it loses vacumn to the power brakes when it gets hot the brake pedal is hard and the brakes are on alittle bit not enough to stop the car but enough to slow the car when in nutral coasting but when the car is cool it does not do that i have the spring in the bottom hose i have done everything i can think of i am almost ready to shoot her and put her out of misery thanks guys

sqzbox 07-10-2010 12:25 PM

The lower hose with the spring in it is the most notorious for collapsing. It rusts or deteriorates over time or if it is out of position (not stretched end to end) it will leave room in the hose for it to collapse.
I didn't even think they made the spring supported lower hoses anymore and went to ribbed style.
I'm not putting all my money on the hose as a problem, I just want to eliminate it as a potential problem. :D

baadgoat65 07-10-2010 12:54 PM

hot 389
hi guys yes you can still get a hose with the spring in it at ames that is whats so confusing about the whole thing everything is new every nut and bolt it is just crazy i was praying someone would think of somthing i was overlooking but thats my luck

lmsport 07-10-2010 01:41 PM

Could it be lean all the time, resulting in the constant increase in temp until it starts to vapor lock, resulting in loss of engine power and vacuum? What pressure radiator cap. I would have at least a 20 lb cap.

sqzbox 07-10-2010 01:53 PM

Not for the lack of trying, Patience is a virtue. Sooner or later we're going to figure this out.
Other questions are,

What temp thermostat are you running?
Horizontal core or vertical?
what year and kind of car is the engine in?
I could be wrong but I think there was a separator plate involved on the water pump on pontiac engines.
Was it left out?
Thermostatic clutch fan or flex?
Correct radiator cap pressure?
What type of temp gauge?
Not testing your mech. ability and you've probably asked yourself these questions already but maybe I've hit on something you might have missed.
From your first post I really don't see why you have this problem. :D

ericnova72 07-10-2010 02:06 PM

What is the initial and total timing #'s you're using?? Are you using vacuum advance, and is it ported or manifold vacuum sourced?

baadgoat65 07-10-2010 02:09 PM

hot 389
hi guys everything is stock it is a 65 gto 389 tripower everything is new it had a frame off resto i will see what the radeator cap pressure is it does start to vapor lock when it starts getting hot i have adjusted the mixture but it doesnt seem to help turning the screws in richens it or is the other way it is a strong odor in the garage but i dont get any black smoke

68NovaSS 07-10-2010 02:13 PM

Thermostat not installed upside down?

baadgoat65 07-10-2010 02:46 PM

hot 389
the timeing is set at 6 before tdc and i have to check to the total advance the vacumn advance is from the manifold i dont know if that is rite or if it should be ported i will check the timeing and post it in a little wile today i have a advance timeing light so i will let you know what the setting are thanks

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