Community Forums

D Lindy · 07-30-2016, 06:02 AM

TONY; I've read most of the reply's/suggestions but didn't see anyone suggest replacing the radiator hoses. If these are old they become spongy and will partially collapse when at times when hot and then restrict the flow of water causing overheating especially when the engine is under load i.e. pulling a hill.

leadman · 07-30-2016, 11:27 PM

D Lindy is correct that a radiator hose can collapse on the inside, especially the one feeding the water pump. It normally has a metal spring on the inside to prevent this but when the hose is old the spring might be corroded and broken. I have also seen the inner layer of the hose separate from the outer layer.
A good practice on an old vehicle that the history is unknown is to replace all of the coolant hoses, flush radiator and block, replace the thermostat, cap, as well as inspecting for coolant leaks from the engine, heater core, etc.

stumpnc · 07-31-2016, 06:33 AM

Is the unit still losing coolant? Yes-Pressure test system. No move to next step
Have you looked at Fan Clutch? Is it engaging properly,Here's how to test
Diagnose Cooling Fan Clutch

TQ60 · 07-31-2016, 09:31 AM

Reading the link reminded me of something...

With engine cold and off grab on fan blade and try pushing toward front and rear of engine while carefully feeling for any movement.

There should be zero other than blade flex but if any is there the bearing is toast.

2 results is first fan does not work and if it is there for long enough time it will vibrate and take out the water pump.

Changed a few back in the day...

Pressure test will show if water pump seal gone but you may need a mirror to see.

Uhrlto · 08-23-2016, 04:49 PM

first of all, I wish to thank everyone who has been involved in this very long post and has stuck with it for the months that I have been trying to diagnose the problem. You have my thanks more than you know. So as the title suggests there has been some headway made in the overheating problem. And to help anyone new looking at this post I'll do a quick readers digest summation so everybody knows what were talking about.
This is an overheating problem concerning a 1992 Fleetwood pace arrow with a 454 V8 engine. We have owned this for almost 9 months now and have only been able to enjoy it twice due to the overheating situation initially it started out with the fluid disappearing and not being able to tell where it was going. There were lots of suggestions but I think as of today I found out where that fluid was mysteriously going.
So everyone suggested that I do a pressure test. So having some spare time I finally got a chance to get down to my local parts place and rent the tool. This is what I found.
With the engine cold, I went ahead and pumped the system slowly up to 18 pounds where I let it sit for a good 20 minutes and there was absolutely no loss of pressure. This made me feel pretty good because I was worried about a cracked block or a bad head gasket. But seeing as pressure was held this sort of eliminated this fear. So the next thing I did was start the engine and bring it up close to operating temperature, basically I ran it long enough to open the thermostat. At that point I shut it down and got another pressure test. I discovered two small leaks on the small hose that connects the filler To the radiator this is where I think I was losing so much fluid. I tightened up both hose clamps and that stop the leak. Once again pumped it up to 18 pounds let it sit no loss of pressure.
next, I checked the original radiator cap And it was bad it would not hold pressure past 8 pounds. So, I went back to the auto parts store purchased a new cap, checked it to make sure it held pressure and it did. Bought some additional Anti freeze went back to the motorhome topped off the radiator, installed the new cap and took it for a drive.

The temperature quickly came up on the gauge and sat at 210, now I have a 190° thermostat installed, so I went ahead and didn't really think too much about it being at 210°. I should probably tell you that the temperature outside was about 87° when I got on the freeway and brought the vehicle up to 65 mph, the wind was blowing right at me so I had a lot of additional windage and I was climbing a slight incline and the temperature stayed at 210, this is with the AC off. I drove it for about another 5 miles when I came to a pretty good incline which I went up at about 50 mph the temperature slowly climbed up to about 225. On the other side of the incline was a nice downhill run to a flat area and the temperature came back down to 210 fairly quickly. So I thought everything was pretty good. I flipped on the air conditioning while on the level ground and the temperature rose again to about 225° I got off the freeway after going about 10 miles and started back to where we store our motorhome most of it was downhill the temperature stayed up at about 225 with the air-conditioning on. Then all of a sudden I got a service engine light that popped on and the temperature rose up to almost 240. This was with the wind at my back and only a slight incline. I kept watching it and it passed 240° and stayed there. I got off the freeway about 4 miles from our storage area, drove the motorhome at about 40 mph the temperature very, very slowly came back down to 210, I went ahead parked it quickly opened up the hood did not see the reservoir overflowing, nor heard any bubbly sounds which is typical of the radiator that's overheating, in fact everything seemed quite normal.
So there you have it, all the facts that I know that happened today I am leaning towards a bad radiator. I have reason to believe it's the original 1992 radiator which would mean it should have been replaced a long time ago, but I'm looking for you gentlemen or ladies to let me know which your thoughts are on this with this new information.
We like the motorhome and are willing to invest more money into it but have to stop sooner or later. And an overheating engine has always been my nightmare with any used vehicle. Tomorrow I'm taking it to a radiator shop and let them look at it, but I would sure love to hear anybody's opinion between now and tomorrow morning Pacific time. Thank you again one and all for all the help you've offered on this very stubburn problem. I would like to bring this particular problem to a close so we can enjoy our motorhome. Thanks again one and all.
Most sincerely Tony and Kay

TQ60 · 08-23-2016, 06:52 PM

Was it really hot?

Get an ir thermometer and check actual temperatures.

Bad sender or wires can cause this.

A chunk of something clogging radiator can also cause this.

A 3 step acid flush can work miracles cleaning systems.

Collect the water as antifreeze not cheap.

Repeat your test run but before running long use thermometer to scan radiator in a grid pattern to confirm starting point.

Check hose temperature too.

Make photos and print them to use to write on maybe.

When it is warmed up scan again.

Go up that hill and scan again

If water pump is not pumping enough water the engine will be hot and radiator not so much.

If part is clogged the rows clogged will be cooler.

Shut off and w quickly try to spin fan by hand and it should be stiff.

If easy it is bad.

Radiator removal on your beast is an 8 hour job each way...A friend is having his done due to pinhole.

We suspect a blockage or lack of something causing the cooling system to ALMOST work.

Fan clutch too.

Uhrlto · 08-24-2016, 04:11 PM

Thank you for the reply Tony and the list of things to do, but I've had it with this dame thing and now its at the shop

I have spent to much time not enjoying our couch. And if I could find the PO that sold us this MH, lieing to me stright faced as I asked him if it over heated at all, I'd choke the crap out of him!

I have sold a lot of vehicles in my 60 years and always told the buyer what he was getting into, so he could make a educated desision.

Sorry for my rant, anyway its at the radiator shop and they do think its totally plugged up, as I do. I'm told its a bear to get the dame thing out so I'm exspecting a big bill, but I told the service manager to replace whatever needs replacing, as I dont want to worry about it overheating in the desert.
So as soon as I know what the actually cause is I'll post it here
Thanks everyone for the help.

Tony

TQ60 · 08-24-2016, 08:46 PM

Do get oem or known good quality parts and replace water pump and fan clutch as one needs to come off anyway and the other is not much more trouble.

All belts and hoses new and keep all old in the "crash box" for emergency roadside use.

Look at row count in the core and if 2 make it 3 as that may be a bit o bucks now it is good investment.

kennyrodgers · 08-25-2016, 12:38 PM

As leadman suggested earlier I've also replaced our fan clutch with a hayden severe duty item. The fan kicks in at 195 and coupled with a new 180 thetmostat she sits at 188 on the Motorway and gets up to 195 on a pull. She sat at 210 all day lonfg with the old Thermostat and fan clutch.
Took me a couple of hours to do but well worth thinking about the fan clutch.
Hope you get it sorted soon.

Uhrlto · 08-25-2016, 06:10 PM

Well I got the call from the shop today. I decided to use the oldest radiator shop in Reno, its been here since we moved here 22 years ago. Anyway Henry called me and reported that its the original radiator, it was 3/4 of the way plugged with sludge. Its a big 4 core brass radiator that he feels can be overhauled and put back in. I told him to do what he thinks best. So he said he would call me when he gets into rodding it to see if it will still work for me. If not he said he can get me a 3 core aluminum for about 245, but hopes the brass one can still be used. Also the fan clutch was leaking fluid, so that will be replaced, apperently the pump has been replaced at one time an is still good. All belts will be replaced and all new hoses, total price 1500.00.

I was exspecting a lot more...dont think I could beat that anywhere. So I'll have the MH back next week and were already planning out trip to Disneyland and Socal on the 9th of Sept.
So I guess this brings this thread almost to an end, there will be one more post after its on the road to report hoe it all works out. But I want all who have contributed to this disscussion to know how greatful Kay and I are for all the help, ideas, thoughts, well you name it, that was given. Be back soon.
Tony & Kay

cwk · 08-25-2016, 06:18 PM

Tony,

Sounds like good news. Very smart move to use a professional shop with a good history. Nice choice.

I am certain that you have learned a lot about your cooling system and will keep an eye on it going forward. You may want to keep an eye on the new hoses and belts to be sure that the clamps are tight and the belts adjusted well. Sometimes the hose clamps may need some tightening after some time as things settle in. Ask the radiator shop what to check for and when. He will have the best advice.

Now, get out there and enjoy!!!

TQ60 · 08-25-2016, 06:57 PM

1500 hundred!

We're you wearing your mask in case someone calls the cops?

great price?

Kenvb · 08-26-2016, 08:21 AM

invest in a code reader..dont be sticking pins in the plug. i am retired GM mechanic, have replaced many computors due to people watching those videos. scanners are not expensive anymore.

Uhrlto · 08-26-2016, 01:19 PM

Quote:

Originally Posted by cwk

Tony,

Sounds like good news. Very smart move to use a professional shop with a good history. Nice choice.

I am certain that you have learned a lot about your cooling system and will keep an eye on it going forward. You may want to keep an eye on the new hoses and belts to be sure that the clamps are tight and the belts adjusted well. Sometimes the hose clamps may need some tightening after some time as things settle in. Ask the radiator shop what to check for and when. He will have the best advice.

Now, get out there and enjoy!!!

Fully Intend to

Weve been wanting to get away since we bought the thing. Now I'm just hopeing that nothing else rears its ugly head (just for awhile) I will stay on thouse clamps as thats where I was losing the fluid that started this post. A tiny, but consistant spray on a part of the radiator mounting flang that was undetected unless under pressur. I will be very pro-active (as I usually am) on the rest of the system, just as I'm anal on changing oil and switching to full synthetics when I can.