Mystery Coolant Leak

[Phil57]

Rich where did you take it? The FL in KZoo does a good job.

[gasman94]

I did go to Kzoo...freightliner Oasis dealer. They work on RV's there, so I am glad that they're so close.

[Phil57]

Don't go to GR FL same owners but huge diff in the service. Cummins Bridge way on Clay in GR is also outstanding. Sorry to hijack.

[gasman94]

Originally Posted by Phil57

Don't go to GR FL same owners but huge diff in the service. Cummins Bridge way on Clay in GR is also outstanding. Sorry to hijack.

No problem. I appreciate the info.

[jbrostek]

While this may not be 100% easy to do, the only way to find out where the coolant is will be to follow the water up the front corner of the block. You have one of 3 issues that could be the problem. A freeze plug that has blown out because the coolant was not the right mix for the temps it saw in the winter, a cracked radiator hose at the water pump, or a failed water pump. I would see no reason the the expansion tank to only drip down that side of the block if its mounted on the other side of the engine.

But if you cannot figure it out, best to take it to an authorized cummins repair shop.

[OldCoot]

Put some food coloring in the water and pour it in the overflow tank and without starting the engine, see where it goes. I suspect the overflow tank or the hose from the tank to the engine is the culprit.

[dontech]

Thanks for the food coloring idea. The problem is that it is not leaking from the overflow tank or any hoses coming from there or the radiator. The ONLY place I can find any water is as shown next to the oil pan.

jbrostek, thanks for your analysis. I will try to get a better look at the water pump, but again, there doesn't seem to be any water coming from that high up. I'll post later if I have more to report.

[jbrostek]

I am just basing it on the last picutres, you have one shot looking up the block and the "wet" area exends at least to the lower radiator hose outlet. But after some research on the Cummins ISB 6.7 for 2008 that was offered in the Berkshire you also have a cooled EGR, which happens to be the big red block on the right hand side looking at the top of the motor towards the radiator. If that is somehow leaking at coolant connection towards the front of the motor it would follow that path.

[dontech]

Yesterday, I got intimate with my engine and laid down on top of it so I could reach further down in front. I could see and feel some water coming from the area of the water pump, but not nearly the volume that is dripping off the bottom of the oil pan. I thoroughly explored around all of the hoses with my fingers and they were dry. So I'm about ready to concede to the water pump theory. I'm going to check in with a Freightliner dealer up the road tomorrow and see what they have to say. I don't have the tools or the desire to try to change the pump myself so I will report back when I learn more.

[dontech]

Here's a quick question I just thought of. If I do decide to drive the coach to the dealer about 40 miles away, I'm sure that the engine is going to go into shut down mode because of low coolant. If I disconnect the sensor from the back of the overflow tank will that bypass the shutdown? I'm thinking that there will still be enough coolant that it won't overheat. I would watch the temp gauge carefully, of course.

[tmmar]

Don,
Don't know if this affects your coach or water pump issue (if that is the cause of your leak) or if Freightliner will give you any assistance with this, but there was a problem with the fan hub that they used. It should have had 5 bolts and only had 4 bolts. Take a look at this thread and maybe Freighliner will help you. If not, at least you can get them to put the 5 bolt hub on. Harp on the fact that this is a safety issue that if the hub comes off while at highway speeds, it could sever hydraulic and other lines and causing accidents. Also, if it does come off it could throw shrapnel out the radiator hitting other vehicles causing accidents. I ended up writing to the DOT and other government agencies (New York State Dept of Consumer Protection) and they got Freightliner to change the hub on my '08 coach when I had it.
Good luck,
Tom

Here is a link to that thread.

http://www.forestriverforums.com/for...ble-37738.html

[NV245]

While not being sure how the low coolant sensor works, (if it is a switch, or a sensor designed to detect open or short) however trying to override the shutdown really increases the possibility of engine overheat damage. When in power reduced mode, the engine starts reducing the number of working cylinders and also alternates the operating cylinders to reduce the heat generated by pumping air through the non-power producing cylinders. Also, the temp sending unit requires liquid for a true reading. If you lack coolant, your gauge could show OK while you are warping the head. Once warped, it can go quite a while before problems show up. Just trying to help you save unnecessary repair and inconvenience. Good luck, and I am interested in the final report.

[rstnfmly]

We had a coolant leak on our 2014 390BH on our first trip last month with only 1,300 miles. We also learned how to get into the engine compartment. It turned out that a pipe that went into the the engine block next to the head where it split off to the turbo charger was loose! It must have come that way ftom the factory because there is no way it could have turned with the hoses on the top. We also had a bad solenoid on the DEF tank. Got a 2 for 1 repair.

Sent from my GT-N5110 using Forest River Forums mobile app

[SKnight]

Here's what I would do, while cold fill the tank slap to the top then drive it there. Carry some water with you that way if it goes into shutdown you can refill it. Leaking like it is the pressure will bleed off fairly quickly so you can remove the radiator cap fairly safely, though still wrap a towel around it and be ready to move just in case.

Pull the cap, fill it back up, finish driving. I wouldn't pull the auto shutdown as that will likely let you know you're running low on water before it gets a chance to heat up.

[Blackrock]

I would sure be looking at the water pump. It has a weep hole where coolant escapes when the shaft seal fails. On a Dodge pickup it's not much of a job but in your MH it could be a booger. Water pump only has two bolts on it and after you unwind the serpentine belt it's not that much of a job.

I work as a mechanic for the Az DOT fleet operations, been doing it for many years now.

[SKnight]

I forgot to mention, if you need to open the cap while the engine is hot, find any cooling system hose you can easily reach and squeeze it. If it squeezes easily, then the system pressure is gone, if it's hard and obviously under pressure, proceed with caution.

[dontech]

OK guys, sorry for keeping you waiting. Thanks to all of you for your encouragement and great information. I decided to change the water pump myself, and like most things moving it turned out to be a lot easier than I expected.

I have detailed, with pictures what is hopefully the beginning of the end of this saga here. If you have any final tips about installing the new pump, please post them here.

[silver]

Originally Posted by dontech

OK guys, sorry for keeping you waiting. Thanks to all of you for your encouragement and great information. I decided to change the water pump myself, and like most things moving it turned out to be a lot easier than I expected.

I have detailed, with pictures what is hopefully the beginning of the end of this saga here. If you have any final tips about installing the new pump, please post them here.

As you are charting new territory for me I have a question. Did you have to remove the fan shroud? It always worries me as there appears to be so little room to work at the front of the engine. I assume you are working from the inside of the coach and not underneath. Could you get a couple pictures of the larger work area?

Thanks and good luck.

[dontech]

Yes, I was working from the bedroom access, sitting on top of the engine. I did not have to remove anything except the belt. There is probably 8 or 10 inches of room to get a wrench with extension in place. I was surprised myself. There is plenty of room on the rocker cover to sit on and it is very substantial. You have to find a place for a foot and be careful not to dislodge any wiring or thin metal tubing that is all around.

If you scroll up in my post on RVPics, you will see a shot of the opening and engine from above.

[gasman94]

Fantastic job on the pics and description, Don. Makes me believe that I will be able to tackle some repairs and maintenance when I'm out of warranty.


Rich