8v92 Overheating

[HighVoltage]

Hi all,

I recently picked up a 94 WB40 that Randy had listed. I am very happy with the decision and have been trying to find the right Bird for us for a couple of years.

We picked it up on Friday at 3am from Florida trying to get it out before Irma got up that way...traffic was a bear for sure.

Checked all fluids, tires etc and headed toward Atlanta. We drove for approximately 6hrs to Tallahassee and got fuel, then headed toward Bainbridge. It was between Bainbridge and Columbus that I noticed the temp creeping up, nothing serious but it was slightly higher than before. Right before we made it to Columbus I got uncomfortable with the temps and pulled over. I had activated the fan override at 190 and the fan had been in this mode for an hour or so before we stopped. When we pulled over the oil was around 240-250 and the water was hovering at 200-215...too hot for me.

Hit the high idle and let it run for 10 min, temps came down, run another 20 and shut it down. Ate some gas station food and checked the coolant level. Sight glass looked empty so we added 2 gal of distilled water. When we saw it in the neck we realized we were overfilling it which was a good thing because we hadn't boiled any off. We then loosened the glass bulb up on the sight glass and drained 2 gal back off, it had been perfect.

So we head off again and trying everything to keep the temps down as near to 190 as possible, 4th gear, 1850rpm, pedaling the gas up and down hills to keep the heat down. Stopping every 25 miles. 8hrs from Bainbridge to Carrollton.

We made it to Heard County and I pulled into a truck mechanic shop. I asked to use his hose to spray out the radiator and he let me. I hosed everything off and walked back up to the cab. It went from 200 to 160 just that quick.

Started driving the last 40 miles of the trip and had to stop once more.

No heat problems at idle.

Here is the raw info:

No coolant loss.

Coolant flow does not seem to be an issue since hosing off the radiator exchanged the heat very rapidly.

House Batteries were at 1.5V when I looked at the coach the week before and the PO filled them with water and had them charging. (13.4V right before we pulled off-with the charger off)

We drove the first 150 Miles with no issues. (ambient temp 70)

Started having issues at (ambient 80 degrees)

Loss of cooling capabilities was linear over time.

Fan output seemed low even at high idle IMO, but my knowledge is limited.

The engine batteries have a battery disconnect on the negative side that does not have continuity in the on or off position (checked when I got home)

I changed 4 of the house batteries when I got home, started the coach up to move it out from under the trees with all of the wind headed our way and checked the fan output. Hit the switch for the override and HOLY SMOKES the fan came on hard, much harder than before.

SO...you may be thinking what the heck is all of this nonsense information.

I have two ideas about what might be the problem. First, the house batteries were junk and as we progressed in the trip the voltage dropped and it caused the electronics to malfunction and did not allow the fan to run at full output.
Second, as the trip progressed the hydraulic pump heated up and was not flowing at a high enough rate because there is an issue with the pump or fan motor.

With the engine batteries not properly grounded because of the faulty disconnect and the house batteries not holding a charge, I am leaning toward the electrical side but am not sure what effect that would have on the hydraulic system.

For now I think the fan is operating correctly and that I will not have any more trouble but I would like some input from some of you to see what your thoughts are.

[isp2952]

It sounds like you may be correct on the electrical issue. These coaches have to have a good source of 12v power or a lot of things don't work properly. I would take it for a test drive when convenient and see if your guess is correct. If you didn't hear or feel the power of the fan before, I'd say without a doubt it wasn't working properly. On mine, when that fan runs and you are near it you feel like you are in a hurricane, pardon the pun.

[atckip]

jacob, My 8v92 would cycle between 180 and 190. My oil temp always run higher but never that high, it could be the guage. Good 12v and a ground will fix lots of problems, but I think your cooling system needs a good check. I believe without 12v your fan should have been running on high. Check the oil level in the hydraulic tank. Running from Florida to Georgia shouldn't create any big heat issues. Good to see another bird in the Atlanta area. I'm close if you need anything

[HighVoltage]

Thank you both for the replies...I am pretty set on the fan being the issue and I need to look into it more. I did see that the oil reservoir for the hyd system was full and the fluid was clean and clear. I found the filter and I have thought about taking that apart to see what it look like. I would imagine it should default to wide open when it malfunctions but I need to dig into a diagram and get a better understanding of the system. The thing that caught my attention the most was after we checked the coolant and let the rig cool down I started it back up and cycled the switch off, waited 15seconds, back on and no noticeable change from the operator seat. I had my friend back at the fan and he said it was coming on....now after I got it home and changed the batteries I hit the switch and like I said, I knew it was on because it pulled the motor down for a split second and I could hear it and I even had the windows closed.

I will investigate further and take it out for a test run now that I'm near the house...On to the list of other issues to fix.

[Gregg]

Jacob,
You seem to be very knowledgeable on tracking things down and being aware of how the coach is operating, at least compared to me when I started. One addition I have found very helpful is Silverleaf. It gives you the DDEC electronic readings so you have a check on your gauges. If you come to pine mountain, I'd be happy to show you our Silverleaf set up.
Gregg

[bubblerboy64]

Just to confirm at least on my coach if you loose 12v the fan defaults to on. I had a cable break to the alternator and wondered why the engine was running about 15 degrees cooler. Fan was on all the time. Can't be of much more help but you do not want to let them over heat. Have you changed the coolant lines to the compressor? How about the water pump and thermostats? If the fan is working and no leaks not a lot else to check. Assuming that the radiator is not plugged up which it sounds like you have checked.

[HighVoltage]

Originally Posted by Gregg

Jacob,
You seem to be very knowledgeable on tracking things down and being aware of how the coach is operating, at least compared to me when I started. One addition I have found very helpful is Silverleaf. It gives you the DDEC electronic readings so you have a check on your gauges. If you come to pine mountain, I'd be happy to show you our Silverleaf set up.
Gregg

Greg,

If I get some time I'd love to swing by and check it out. Randy was telling me about Silverleaf and it sounds like a good investment. With DDEC II do you have access to a large variety of data or is it somewhat limited compared to newer engine management?

[Gregg]

Jacob,
Less than the newer coaches,but we got the last year for the 8V92 and I'm convinced it is a great year to own. See you at WOG. I'm just down the street from Randy.
Gregg

[HighVoltage]

Originally Posted by bubblerboy64

Just to confirm at least on my coach if you loose 12v the fan defaults to on. I had a cable break to the alternator and wondered why the engine was running about 15 degrees cooler. Fan was on all the time. Can't be of much more help but you do not want to let them over heat. Have you changed the coolant lines to the compressor? How about the water pump and thermostats? If the fan is working and no leaks not a lot else to check. Assuming that the radiator is not plugged up which it sounds like you have checked.

Haven't had a great deal of time with it since I picked it up Friday but I did look at the compressor lines when I got home and they have been recently replaced. That makes me think the coolant is relatively new but I plan on servicing it soon to be sure. Not sure on the thermostats but I read that they default to open. Still a few things to look at when I get back home from work Friday.

[bubblerboy64]

I guess the other thing not mentioned is the gauge itself. One of those optical heat measuring deals is a good thing to have. I have one and don't use it as much as I should . Of couse you did say the temperature went up after driving some distance. You also mentioned screwing out the glass on the over flow tank? Hard to do that I would think without breaking the glass . Let us know what you figure out . Over heating is something we all worry about.