Gundog wrote:
My slobber tube is only about 1' long sticking straight down and the end is cut at an angle. I will have to do mine a little differently but with the same concept.
Thanks Mike
Gundog,
The "angle" cut is done that way for a reason. Long, long ago, way before STAR WARS, engine crank case pressure in gas engines, was relieved much the same way in say, the '50s and early '60s. The "blow-by tube" was hung straight down, just like yours and many others, and cut at an angle, just like yours and others. The term they used waaaaaaaaay back then was "Road Draft Tube".
They (the then engineers) calculated the air velocity traveling under the vehicle, would "draft" those fumes/oil mist/crank case pressure, out of the engine, by cutting it at an angle. Well, way back then, it was the best they had.
But, today, in many of our diesel engine, like the CAT 3126 and C-7, that "road draft" system ain't gonna cut it due to potentially improper amount of oil and other reasons. So, just as you're planning, get it extended out towards the bumper/rear cap lower of the coach. And do make sure that, your dip stick is marked correctly for the proper amount of oil for your engine.
Scott
Gundog wrote:
Do you have any more pictures of the slobber tube Mod?
Here's the slobber tube as it came from the factory. You can see how much oil is on the end. The slip joint leads to the extension piping.
I went with 1-1/2 PVC, 1-1/4 would have worked as well. An 1-1/4 to 1-1/2 slip joint makes the connection.
Here's the far end. My temporary pipe hanger became permanent when the pipe hanger I bought for the job got used on the generator tailpipe.
jplante4 wrote:
That's true of all rear radiator diesel pushers. On a CAT, the "slobber tube" (crankcase vent) dumps out under the engine and gets sucked into the charge air cooler and radiator. The fix is to build a slobber extension.
Some coaches have tried to solve this issue by putting the radiator on the side. In order to do this, they set up a maintenance prone hydraulic drive for the fan. Also, all piping is longer increasing the chances of a rock getting kicked up and causing a leak.
If you have a rear rad, yearly degreasing and cleaning is a must.
Do you have any more pictures of the slobber tube Mod?
kmb1966 wrote:
Thank you for the responses so far. I asked this person for more details of this overheating claim. It goes like this:
The diesel engine is in the rear, the radiator is in the rear. His theory is that when or if there was ever an OIL LEAK, the oil leak while driving gets on the radiator, clogs the radiator not allowing it to cool. Even after the oil leak is repaired, the radiator remains clogged until it is removed and cleaned. Hmmmm............
Your coworkers theory has some merit but the overheating due to radiator oil fouling isn't a west Texas or even the time of the year problem. You could overheat anywhere and time with a fouled radiator stack. Outside air temp contributes some but is normally not the trigger for an event. The problem with the theory is specific multiple events must first occur to achieve the end result of an overheat all of which can be avoided with a proactive and effective preventative maintenance program.
And the problem isn't unique to rear engine diesels. The oil fill on a Ford F53 chassis is directly above the left corner of the radiator. Get sloppy during an oil change enough times and you'll easier foul the radiator. Transmission dipstick, and the only way to refill after a drain, is over the right corner.
kmb1966 wrote:
I am considering a 2003 Newmar Dutchstar with a Cat Diesel that has become available in my area. This unit has 33,000 miles on it, 2,000 hours on the Onan. This unit belongs to a neighbor friend of mine, and I have been around this unit for about 10 years now, camping together. I have spent the last several weeks going over this unit, checking it all out anyway, and then suddenly a co-worker tells me that I should be aware that "DIESELS LIKE TO OVERHEAT IN THE HOT SUMMER IF DRIVING IN WEST TEXAS HEAT 110 DEGREE WEATHER".
I have never heard of this at all. My gas unit has never overheated but the Onan gas generator did once.
My question is, IS THERE ANY TRUTH TO THIS ? I mostly drive in the summertime because my wife is a school teacher and we mostly get to go on vacation in the summer when it is very hot. We like to travel west (which puts us crossing Texas).
Ok,
You stated you've been around this RV and been camping together for a period of 10 years, correct? If so, did you actually travel together? If so, did you see or hear the owner EVER complain about ANY overheating conditions in that 10 year period? If you've never heard of seen him complain on any heating issues, then logically, it's not gonna heat when you purchase it. Now, of course things wear out, get stuck and all that so, the "Potential" for overheating is there. But, the probability should be way down.
I'm also assuming that you more than likely, being a somewhat close friend of this neighbor, know the service and maintenance history of this coach. And if that's the case, they you already know this coaches operating circumstances, correct?
You kinda need to sit down with this co-worker and do a bit of explaining on the fact that NOT ALL DIESELS are the same, operate the same, have the same issues and troubles, and more. There's a whole ton of CAT owners on here and other RV forums that are completely happy with their CAT engines. All you need to do is ask.
Scott
