I have the no heat problem. I had stop leak in it and I guess its plugged up the core.
I heard from an old mechanic that you can run the thing backward using those T fittings. So I am doing that. You guys think it would work ??? or make a different problem somewhere else ???


Now I have a nice gusher coming out of the in line when I cut it and ran it, but nothing coming out the out hose from the fire wall after I cut that.


But the other end of the hose has a sporadic foaming gushing thing flowing out of it. That's the hose that connects to the "out" hose from the firewall. How come it has water coming in - to the out line ???


Thanks.
Srinath.

 

You can either try back-flushing it and see what happens or you can replace it.

Good luck.

 

I've rigged it up backwards and drove it.
It seems to be heating up.
Of course how to tell if its got heat on a 75 degree day is anyone's guess. Under hood is 90, and I got 90 degree air, and putting it in cold gets me 75 degree air - however I suspect it will get warmer and warmer as the flushing get better and better and its cleaner and cleaner.
Thanks.
Srinath.

 

I may have a heater core issue as well, still testing it out.

Where exactly are you putting your thermometers?
And what is the engine temp when you take these measurements?

 

Just doing some wild suggestions maybe. If you can disconnect both hoses and fill the core with a vinegar mix for a while and then flush it, it might help clean out the calcium deposits from using tap water in the cooling system. A vinegar solution will clean a coffee maker.
Are you sure the blend door is working okay?

Way back in the 70's, I used hard tap water for the cooling system in my 70 Mustang and it plugged the heater core. I removed it and took it to a radiator shop and asked if they could clean it out. They said no. So, I replaced it with a new one. Since then I use distilled water in the cooling system and batteries.

 

If you DO end up having to go in and replace the heater core.....also REPLACE YOUR AC/HEAT "BLEND DOOR"!! Trust me.......if yours hasn't started to fail yet it will.

It's all in there under the dash & the entire dash has to come out to do all this so might as well knock 'em both out at once since the blend door (newer version by Doorman with metal hinge adapter thing) is only like $25.

Good luck!

 

Mine has been plugged ever since I got mine a while back, it has just not got cold enough to really need heat.

I have the replacement heater core, its said to be a 10-12hr job based on YouTube.

 

My heat problem got semi fixed last year and even since I have had it losing coolant. Suspect that I have a head gasket leak or something similar that only happens when stuck in traffic.
I'm looking into a engine replacement, its near 300K and known issue, 50 psi compression in 2 cyl. Time to put my thinking cap on and try a swap to a WAP block 4,6.
Thanks.
Srinath.

 

What? You have a blown engine, the OP has a clogged heater that he had 2 full years ago and surely has fixed by now.

You state that you lose coolant "only while stuck in traffic." This is not an indicator of a failed head gasket, but you also report 50 psi on a compression test, and this is enough of a problem that taking the head off is the least you can do. My 4.6 with the bad head gasket dumped it's oil all over the passenger side of my truck. I did not bother with the compression test, I just took the truck to the shop and had a head gasket installed. They wanted me to get a full rebuild, I talked them down by point to the fact that they (the engine builder) knows that there is an issue with the passenger side head gasket. I think the head gasket issue in manufacturing is closer to the #4 cylinder, not the #2. In my case, oil control became the issue, not coolant loss.

 

I was the original poster.
OK the problem has been morphing and driving me crazy for 2 yrs and there may be 2-3 problems @ hand.
Its got 300K on it approximately. Odo died @ 279 ~2yrs ago, and was iffy for the last 10k or so. So 300K is a good guess and likely the minimum.
It boils coolant over the top of the catch can in the vent of the catch can.
The gauge will read hot, oil light will come on and sometimes check engine comes on etc only in traffic. It doesn't slowly heat up, it will be running along normal temp, usually the temp will get lower for a few mins and the air will start to get cold inside the cabin and abruptly it will shoot to max while the air stays cold, then it will drop to normal all the while staying cold and usually in a few mins it starts blowing warm again.
I ran it out of coolant Jan 5th (coldest day of this winter @ 6 am no less, it was a nice 8-10 degrees) and subsequent flushes got a heater core full of rust flushed out.
Independent of this its got 50 psi in 2 cyl, and a few more that's not much better either. That's been its situation for 1.5+ yrs.
I am not so sure where the coolant is even going, something blocked in the engine block and that causes boiling off in 1 spot, and as the thing boils it sends coolant bubbling into the reservoir, and overflowing ??? No idea.

At this point I am not even sure if this motor can be saved, what if it has a crack in the head that open up only when it gets hotter than normal.

Anyway I am thinking of a teksid block and NPI heads ithat I can get a good look at before assembling and getting it to where I am near sure it will work. Its only slightly more $$ than an identical F150 motor swap.

Thanks.
Srinath.