Thanks a lot for all the check primem, I'll take a look at the rad etc and see if I notice any of the signs you listed. Will prob just buy a new rad cap anyway to eliminate that potential problem.

Will let you know what I find!

 

Will,
Don't know if your vehicle has an A I R pump on it. (AIR= Fords air injector reactor)
If it does have one and it is still connected and working , it is supposed to pump additional air into the exhaust manifolds when warming up to help clean up the exhaust and speed up oxygen sensor operation. Once the engine reaches operating temp a vacuum controlled valve is supposed to divert that addl air to the converter to help it do it's job. I am wondering if that addl air is "always"being directed to the manifolds instead of being directed to the converter which has a pipe connection for that very purpose,,,,,,,,if it is the correct converter. I know those converters ran about $600 bucks when they needed to be replaced and just maybe someone has changed the system to save a few bucks. That is why it is difficult to diagnose without actually being there to see what is what.

 

Hanky,
There's no doubt in my mind that the last person who got work done on this did it on the cheap, and the converter was indeed far too small. plus when they did the emission test for this the O2 sensor was in the wrong place, which seemed a little strange.
We've now replaced the muffler and converter, the converter cost $300 U.S. plus labour, but I can't imagine that the muffler shop attached something which wasn't meant for the vehicle type, as that's what they specialize in and they have an excellent reputation.
The AIR question is an interesting one, and I'll definitely look into it. I think at this point my main focus will be on trying to figure out why the coolant is misbehaving. It drove well today but again when I stopped on a SLIGHT angle the coolant tank started hissing and popping and some came out of the overflow. I'm inclined to agree with prim's suggestion that air is somehow getting into the coolant tank. First step will be to replace the cap I suppose.

 

the only reason coolant flows to the overflow is if the system overheats, system pressure gets to high and opens the rad cap. If this is occurring at low temps...212*F, the rad cap is nfg or the system is leaking. if its occurring at high temps 230*F the system can't get rid of xs heat.

 

Hey guys,
As an update, I replaced the rad cap and just yesterday we took a drive over a steep, long hill, and the engine started overheating like crazy, to the point where the temp guage was at max. I couldn't stop on the hill as every time I do the darn coolant overflows, so at the top I stopped on a level surface and the thing started gushing out coolant everywhere, steam like crazy, making all sorts of crazy sounds.
By this stage, I had been getting the feeling that the rad was plugged, and this confirmed it big time. All the coolant was gone by now so I could see the bottom of the reservoir, and there was so much gunk in there. So I filled it with more coolant and took it real slow, then today took it in and the mechanic took one look and said both the radiator and fan clutch needed replacing. Apparently not even a flush would be enoug, as the calcification and build-up were too great and the rad was in poor condition
So, $750 later, here we are. I just hope that this particular episode didn't damage other engine components!

 

That calcification has also been working on the water pump and it would have been a good time to replace that with the radiator. I realize it adds addl$$ to the bill, but better to replace it while everything was open especially if it has to your knowledge never been replaced. Let's hope you can enjoy your trip without any further problems.

 

Agreed on the water pump, but we only had a day to get everything fixed up before we had to head to Phoenix and fly out to Mexico, and they were working on the rad until late, so I didn't press the matter. Hopefully won't be an issue!

There IS one more issue haha, and that's an engine cutout problem at idle and in first gear at low/no accelerate. Doesn't seem to affect performance on the road, but could this be a fuel issue?

 

Does your vehicle have one or two gas tanks?
There are several possibles and further checks would need to be done before any suggestions could be offered. Among the items that could be involved are;
low charging voltage , questionable connections to fuel pump system, Throttle position sensor not making good connection at idle position, incorrect RPM info being fed to the computer, loss of RPM signal from dist, possible ECA problem. None of these could be the cause of the problem, but we need to start somewhere and without the necessary test equip shooting from the hip can get very expensive. Even something like a vacuum leak could contribute to the problem. Was it still cutting off after the overheating problem was corrected?

 

Hey Hanky,
I'm fairly sure it only has one fuel tank, however I could be mistaken on that one. Although I hear that some of these models have two fuel pumps - one in the tank and one outside.
The engine is still cutting out after they completely replaced the radiator and fan clutch. That was yesterday, and if anything it's gotten worse today, with the engine cutting out a lot when I was maneuvering the RV into a back in spot at the RV park. Seems to be directly related to acceleration, and only in first gear - if I keep my foot solidly on the accelerator, i.e. so that there's sufficient RPM, it doesn't seem to cut out.

 

If your vehicle has only one tank , it has a low pressure pump in the tank and a hi press pump mounted under the driver's seat on the left chassis rail.

If you have two tanks, it still has a low press pump in the tanks and hi press pump on the chassis tail.
In between either of the set-ups, is a reservoir for the one tank set-up and a switching valve for the two tank set-up. If you had two tanks there should be a switch on the dash to choose Ft or Rear tank.
Does it cut off in drive and reverse or only drive alone?
Could be someone backed out the low idle limit screw on the throttle body, the by-pass air solenoid is malfunctioning and depending on which trans gear you select could involve the manual lever position switch (neutral safety switch on the trans).
If I keep offering anymore suggestions you will shell out enough to get another vehicle !!