Community Forums

Mule Skinner · 11-15-2009, 10:37 AM

How can I loose 4 gallons of coolant without seeing a drop any where? I fear the worst and hope for the best.
I know radiators have been the issues for most. Could be a head gasket? I purchased new in August of 2005. I think Cummins is a five year warrantee. Dose this include the cooling system?
I’m in the San Jose, CA area and plan on dropping this rig of at Leales. I have seen posts here about them doing the radiator repair.

#2 Electrical, I just had Cummins trouble shoot a loss of power, in Reno. Found a clogged fuel filter. After coming home, storing for a month, I picked the MH up to make a run to Disney Land and found the volt meter at 0. The step comes out about 1” and stops? I think the house batteries are near dead.
What could the Tec at Cummins have done to kill the charging system?

Several trouble free years, now, it’s my turn!

EngineerMike · 11-15-2009, 11:26 AM

Cooling system is WRV, not Cummins. Sounds like your leak may be only under pressure so you lose steam rather than liquid. Try running up to temp, then idling the rig for about 20 minutes (w/full coolant) to see if you find any drips before turning it in for service; you may find the leak that way. Check oil for a milky look indicating coolant in the oil; may have to run engine for a while to get it mixed if coach has been sitting for a while. Also, oil level might indicate overfull if you lost gallons into the crankcase, although Mike Young from Cummins said overfull won't stand long as the crankcase pressure will send excess out the blow-by and this amount of volume would make a grand mess.

SteveS · 11-15-2009, 05:34 PM

Dan - You didn't say over what period of time you lost the coolant. You could easily lose a half gallon or maybe more on a trip without even noticing. Driving long distances under heavy loads could cause you to lose it through one of the hoses, couplings, or radiator when the engine is hottest. Then before you stop, the engine may have cooled down enough so pressure wasn't as high and the leak stopped. You wouldn't notice this type of leak. Get the engine hot and let it run awhile while stopped and inspect for a leak. I really thing you would have noticed oil issues if you had a head gasket problem.

Barbaraok · 11-15-2009, 07:07 PM

For my own education here, wouldn't you see the temperature go up if you lost 4 gallons of coolant? We've seen a change of ~5 degrees when we have had the filter changed and they didn't put in about a pint to make up for what was lost. It took a pint, the temperature was right down where she belonged after that. Of course, ours is an older coach, so that might make a difference?

Did you have the TV booster on? There are a lot of small draws on the house system that if you didn't have it plugged in, could drain the battery over the course of a month unless you threw the battery disconnect switch.

Barb

takepride · 11-17-2009, 09:03 PM

Dan:

On the coolant, I just had the same issue. Turns out there were three loose clamps with the leak happening only under pressure and then blowing off as steam or evaporating on hot surfaces. Tightened them all, pressure tested system. All okay now. As per my earlier thread, this coolant loss had been occuring over the last two years.

The engine did eventually get too hot with enough fluid loss and I would refill with no problems for another few thousand miles. Last year I also replaced a 5"-6" elbow hose that was bulging. Hoping this problem is now put to bed.

On the electrical issue. I had the same problem just after some work from Cummins Cal Pacific. Turns out the 300 amp fuse was blown. They replaced it. I refused to pay it. They wrote it off. I somehow doubted I was able to blow the fuse while it was in their possession. Just the principle.

Mule Skinner · 11-18-2009, 10:55 PM

Thanks all for the responses,
I’ve been away for a few day’s.
I filled the coolant system before the 800 mile trip. It took 3 Gallons at that time.
After this last trip and letting the coach set for a month, then a 5 mile trip from the storage yard to my home. It did heat up enough to set off the alarm.
I plan to bring the MH to my house and take a look this weekend. I will check as suggested, leave running and look for any leaks. (I’ve done this, but will look again).
I have seen small amounts of coolant under the rear of the MH that looked like it came from the overflow tube. (?)
The seal on the cap looks dry. I’ll replace that. Any one know the p/n ?. It might show on the cap?
After cooling I’ll check all of the hose clamps as well.
I’ll look at the oil for contamination (water, milky looking) I checked before the 800 mile trip and level was safe and black as it should be. Oil change at Christmas is my gift every year. Less than 10,000 mi.

The main cut-off was switched off, so there should not be any drain on the batteries. After fiddling with the battery connections, I did see the volt meter come back to 14 volts. The step still not coming all the way out.
I am going to remove and clean the battery clamps as well.

Thanks again for the ideas and support!

Dan

EngineerMike · 11-19-2009, 10:20 AM

IIWM, I'd start w/the cap; take it to NAPA, Kragen, Autozone till you find one that matches for size & type. They'll have a rack and if that doesn't work the counter folks can fish one out that matches.

Then, while still cold, start putting a wrench on all radiator fittings you can find. You'll probably discover one or more that are not fully snug. I did. I'm thinking the hose material conforms some over time so that a hose that was once tight can loosen up. I found a drip under mine when it was cold and setting for several weeks. the hose connection above it showed a stain where it had leaked when hot, but it had progressed so it didn't need pressure to leak. Caught it around the 1/2 gallon mark. Now fluid stays above the sight glass after two long trips.

Old Scout · 11-20-2009, 08:11 AM

At the risk of asking the obvious--I assume you are checking the coolant level when the engine is hot/running. If you fill at/above the sight-glass when engine is cold, it will be over full and will simply push out the overflow as you go down the road.....

EngineerMike · 11-20-2009, 11:04 AM

Old- I get a teeny dribble out into my ex-Windex jug overflow, just enough to wet the bottom maybe 1/4". Now I'm always above the sight glass cold or running.

I think that is a function of the 08-09 radiator redesign where all the (4) heat exchangers get fresh air directly, instead of having one in front of the other so the front one heats air for the 2nd, 2nd heats it some more for the 3rd, and 3rd heats it some more still for the engine radiator which is last to receive the air flow. The latest model radiators have the intercooler at top, then engine radiator below, then hydraulic oil, then dash AC refrigerant. With this always fresh air cooling for the engine, mine tops out at about 203 degrees (on the Actia) under worst case driving, but only rarely sneaks above 195. Less coolant expansion, less coolant head space needed in the surge tank.

For 07 & earlier, I'd use your formula of filling with engine cold but running to see coolant in the sight glass, or
Add a coolant recovery tank then fill to the top. With the recovery tank (I did that on my 06), you should have coolant in the sight glass when dead cold. (well, maybe not cold-wind-blowing-off-Lake-Michigan-in-the-dead-of-winter cold; everything shrinks when its that kinda cold)