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Topic: Latest problem - overheat/coolant leak/fan/pump failure (Read 1251 times) previous topic - next topic

Latest problem - overheat/coolant leak/fan/pump failure

Wednesday morning I drove the coach into town while Jo Ann got the mail, then met me to attach the Jeep to the coach. This time there was no air problem, as the previous day the two mobile mechanics replaced the air compressor and air dryer. We headed down the road towards Stillwater, OK. We stopped in Mount Vernon, MO for lunch, and just after leaving that town I noticed that the water temperature was rising quickly, so I pulled over. A fountain of coolant was coming out of the top of the overflow tank, so I called CoachNet. A large truck arrived in due course. Unfortunately he didn't have the large air tool to remove the wheel lug nuts, so a smaller truck with the correct tool arrived. The axle was removed and we were towed to the Joplin Freightliner shop. They didn't have hookups, so we spent the night in a hotel not very far away. The next morning they figured out that the problem was with the radiator fan setup and they were not able to get parts. The called around and found Cabin Diesel, in Big Cabin, OK would be able to do the work, so CoachNet sent the same man and large truck to take us there. Fortunately Big Cabin is on the way, so at least we weren't backtracking.

Cabin Diesel wasn't able to get us in until this morning, but they have a small bare-bones FHU campground (30/50A) so we're fine. It didn't take them long to decide that we needed all new fans, pump, and solenoid, and a phone call to Foretravel arranged for it all to be overnighted, so maybe tomorrow we'll finally get to Stillwater.

We left our house for Stillwater on 3 December but didn't even get out of town that day. With luck we may get there two weeks later - just in time to take off for Christmas break!

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #1 –
Sorry for your challenges. My hunting dog trainer Ronnie Smith) lives in Big Cabin OK, been past that shop and "campground" many times. Hope you get going

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #2 –
Thanks, Tim. As we were driving down I-44 I noticed the signs for Miami and remembered that that's where the Newell factory is. I mentioned to the tow truck driver that I wished I had remembered about them earlier, as maybe that would have saved CoachNet a few dollars. As it turned out, though, this is where Newell sends the engine/transmission service work, so I guess I lucked out.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #3 –
   Hi David,
    Sorry to hear of you coach engine troubles.
    Hope that you are up and running soon and the rest of your trip goes smoothly.
          Take Care ---Jim

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #4 –
Sorry for your troubles David... I feel your pain. :(

see ya
ken

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #5 –
David  ----  What engine do you have in your rig?  Is the cooling fan setup part of the steering hydraulics?  Thanks, may you be granted patience thru all of this.  Take care and God bless your days  ----  Fritz

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #6 –
Fritz, I have a Detroit 6V92TA. Steering doesn't seem to be affected. Is that the next problem I'll have?

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #7 –
David,

No, PS pump is on the end of the engine facing the front.

Would have been nice to have an tech savvy mechanic look at it first as super unlikely that all components would go down at the same time. This sounds much like many automotive shops that replace everything as that's sure to cure it. Probably does but also cleans out the wallet at the same time. They will probably say the pump failed and contaminated the fan motors. How many miles on your coach? You probably know by now that this one is going to be $$$$$$.

Next summer, I plan (good word, plan) to buy a couple of large aluminum radiators/fans and fit them behind the nose grills. Very easy to do but much more difficult to route the supply piping back to the engine. Have been looking at flexible hot water plastic that will stand up to high temps. Fairly expensive but cheaper than copper would be. Then I will remove all the junk associated with the hydraulic setup and just install several 12V fans on the outside of the rear radiator facing the grill. There is actually plenty of room on the opposite side from the rear radiator but I would like to take advantage of the ram air. Two front radiators will give about the same square footage as the OEM rear radiator for a small fraction of the price. Will save somewhere around 30HP with ram air doing most of the cooling at highway speeds.

I took a Mercedes 220D and just removed the fan replacing it with an electric one. Almost never had to switch it on. The advantage here was the noise the stock fan made. Hard to find an electric fan that would totally do the job in the rear on a RV.

VW Vanagons, Porsche 911/930 do it with great success. Even the old style VW buses made in Mexico installed the water cooled engine and added a front radiator.

Hydraulic pump/motor/belt failures have been responsible for much of the engine damage/failures to RV pusher diesels. It's a really bad idea in my opinion. Could have easily been designed around but that might have taken some engineering.

Pierce

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #8 –
Pierce,

Interesting concept.  How much larger capacity water pump would be needed to overcome the friction/resistance of all those yards of extra "radiator hose".

Am familiar with the VW Vanagon rear engine/front radiator, but the "run" from engine to nose is an order of magnitude less.

I DO see a front radiator, "T'ed" off the dash heater core (so no new hoses to run) as a supplement to the existing cooling.  And, if the rear radiator fan is thermostatically controlled, this would keep the fan on low/less HP draw more of the time.

As you know, you can never have zero air flow through the rear cooling package on any engine/chassis with a Charge Air Cooler, as that would allow intake air temperatures to rise dangerously. That is why the thermostatically controlled fans are low/high, not off/on.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #9 –
Another option would be to go up on the top of the rear roof,a large radiator in a fiberglass air duct scoop that had electric fans installed and the back of the duct open to discharge downward out the rear when driving. Something like that might be easier to fabricate than trying to run coolant lines 40' forward.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #10 –
You would still need a good air flow over CAC as Wolfe explained.
JohnH

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #11 –
Brett,

Don't think the friction loss would be that high sending coolant through 1 1/4" or 1 1/2" lines. VW has a fairly small water pump and even had to install a flat washer with a hole in it as a flow restrictor so the coolant would spend enough time in the radiator to cool before heading back.

Kent Spears did exactly that by installing a front radiator and "T"ing into the heater. Not sure if he installed one for each grill or a single radiator on one side. Kent, how about info on what you did and how well it worked. Our Foretraves have an extra pump to aid heater flow but even with that, I don't think the amount of returning coolant would allow the removal of the hydraulic fans. Possibly electric fans could be installed and would be enough to cool with help from the front radiators from the stock heater lines. Could install the front radiators/stock heater lines, install electric fans on the rear radiator, pull the hydraulic motor belt off and see how it does in summer on grades.

I did see a 40 foot tour bus in San Francisco with a flat air cooled diesel. It only had a single large electric fan above for all the cooling but even idling, it never came on while I was watching.

Detroits use an aftercooler so don't worry about airflow across the intercooler like Cummins. There are a lot of powerful electric fans available that could be switched on with a boost pressure switch. My Porsche 930 just uses air passing through it on the way to the engine fan. (mine is an air cooled model) An electric fan could be used on the face of an intercooler tied into a boost sensor. My 930 has a pressure sensor that activates a 7th fuel injector to keep the engine cool when petal to metal. Also puts out a little black smoke from the extra fuel.


Looking at a GV styled Foretravel, passing two coolant pipes through the generator and cargo compartments would be easy with the main difficulty getting them between the water tanks and the floor just in front of the engine. Copper would be good as it is thin wall and would use the least outside diameter for the amount of coolant flowing. Looking at the space above the tanks, there is enough space but just a matter of installing it there.

Household hot water plastic pipe would be marginal but there are several manufactures of plastic tubing that operate at much higher temperature and pressure than would be seen in a Foretravel.

Pierce

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #12 –
Part of the problem is that many, if not most or even all, of the parts are not available, even from Foretravel. I probably won't know until they actually start tearing into it tomorrow, but I suspect that the hoses are probably pretty well shot, too.

Yes, I know the price will be pretty high. I was pretty shocked when they gave me the estimate, as it was 10X what I was thinking it might be. Part of that was an estimate of $500 for overnighting the parts from Foretravel. Unfortunately someone at Foretravel was operating on autopilot and sent them 2nd-day air, so the parts won't get here until tomorrow morning. It sounds like they can get the work done fairly quickly, so we may make it to Stillwater tomorrow afternoon, two weeks from when we were supposed to arrive. Stillwater is about 6 hours from where we started, so we're making good time - about 100 miles per week. I think that's about what the pioneers figured on.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #13 –
David, I just saw this thread. Big Cabin is one of the best in this region but as you might guess they are used to dealing with Newel owners. As Pierce said it is very unlikely that all of the cooling components would be bad at the same time. Unless you had a visible leak of hydraulic fluid from a bad seal I'm betting it is something fairly simple.

I can understand that Cabin Diesel would like to replace all of the components to insure compatibility since some of the parts are obsolete but they don't have to do that. That's just what Newel would do. I know it may be a little late now but make sure the problem is not the fan speed solenoid or the hydraulic pump pulley or belts. 

The difference in cost can be thousands.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #14 –
The belt and tensioner were replaced last week. I had noticed that the old belt was letting the tensioner hit the pump and the belt was trying to escape. I had the mobile mechanics, who did the compressor and air dryer, get a new tensioner. They took the old one off before ordering so they would be sure they had the right part. I took the old belt off, went down to O'Reilly's to get a replacement, and put it on. One of the mechanics mentioned that I should have an 8-rib belt, and I bought a 6-rib (the one on the coach and the spare that came with the coach were both 6-rib). I guess I'll find out tomorrow what actually happens. I wonder if Cabin Diesel ordered everything they might need so that it is all here and they can get me going as quickly as possible (we've been here since Thursday), and if they don't need something they can either send it back to Foretravel or keep it on their shelf in case someone else needs it. They quoted everything in there just so I wouldn't be shocked at the bill. If they can do the work for less than the estimate then I'll be happier.

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #15 –
David  ----  Our 91 GV has the cooling fan hydraulics runoff of the steering gear hydraulics.  Depending on your cooling fan issues, if yours is as mine, you may want to replace your steering gear hydraulics to prevent any contamination from taking out your steering box.  You've probably already changed out the power steering fluid if they are in the same system.  Hope things go smoothly for you, take care and have a great day.  ----  Fritz

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #16 –
@Fritz on my 92' they separated the fan hydraulics from the power steering. I'm pretty sure it was that way on Kent Speer's 93' so bet that Davids fan and power steering are on separate systems too.

see ya
ken

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #17 –
Just raise the bed and look down at the driver's end. You can't miss the direct drive (no belt) pump and hoses.

Pierce

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #18 –
@David Hope this isn't too late but before they start tearing stuff apart have them check both fan rpms and insert a pressure gauge on the pressure side of the fans and get get a reading. You need these so you have a baseline to determine if they are making progress or not.

If you have slow fan speed (should be around 2000 rpm) at full throttle. Check with James @FOT for the correct fan speed for your coach. Actually I have a hand written fan speed sheet he sent me. (attached below)

I ended up replacing just about everything in my system. Pump, fan motor, hoses, pressure controller, and solenoid. :(

If you want to talk give me a call. I can offer some comic relief if nothing else. :) 303 810-0000

see ya
ken

Re: Latest problem - overheat/coolant leak/fan/pump failure

Reply #19 –
Yes, review my old posts on belt and alignment along with the correct belt number. It IS an 8 rib belt. Foretravel got the part number wrong. This along with poor factory set up has a ruined several engines from overheating and operator inattention to warning lights and gauges.

Pierce