Diesel pusher overheating

[NHRA225]

Mine>>

[akeyzoo]

I think a well made catch can is the best long term solution. Lots of posts and pictures. I used a plastic costco nut container, with many holes on the top and steel wool inside. Key is you do not want to restrict the vent tube, so keep that in mind. You can make one for free with things laying around the house. Very rarely will you need to empty it.

Chris

[greystroke]

Originally Posted by KDP246

Thanks for many good ideas. Now re. Slobber tube. Do you lengthin it to be below the radiator, direct it below and behind the rad or what?

I used flexible PVC from HD or Lowes.

Just slide it on and cut it so it is beyond the radiator or CAC. Then secure it and add a bottle if you want.

[ahicks]

I was concerned about restrictions and used a straight piece of 1" PVC. It's installed so there's a slight angle down towards the back, preventing the possibility of moisture collecting and freezing in a low spot.

Tried the vented container first, but it just seemed I was creating another mess after a trip or 2 with that. PVC is run back to just in front of the rear bumper. After 4 years now, no downside. Never notice anything on the front of the toad either, which I thought might be the case early on.

[csrrsr]

Originally Posted by ahicks

I was concerned about restrictions and used a straight piece of 1" PVC. It's installed so there's a slight angle down towards the back, preventing the possibility of moisture collecting and freezing in a low spot.

Tried the vented container first, but it just seemed I was creating another mess after a trip or 2 with that. PVC is run back to just in front of the rear bumper. After 4 years now, no downside. Never notice anything on the front of the toad either, which I thought might be the case early on.

I had a muffler man run a pipe to just under the rear bumper and have never noticed anything on the toad. But when I park for an extended period there's a good spot of oil on the ground.

[mel s]

Originally Posted by KDP246

Thanks for many good ideas.
Now re. Slobber tube.
Do you lengthen it to be below the radiator, direct it below and behind the rad or what?

KDP246
Extend the slobber tube to a point below and beyond the radiator at a downward slope ...without a low spot, (aka; droop), which might fill with condensation/moisture and plug the tube.
Mel
'96 Safari

[sevenmacs]

back to the overheating issue of rear radiators, a big difference between rear and side is that side mount have the rear part of engine compartment open allowing hot air to escape. Rear mounts trap all that heat in making the ambient temp around engine much higher. This has to increase engine temp. I thought about opening up the area above my radiator to allow air flow, its just a rubber closure strip. Just a thought to consider.

[mackwrench]

The rear radiator setup is designed to force all air to exit though the radiator. Removing the closure strip is going to allow that much air to bypass radiator and could affect cooling. A better solution is to find a way to introduce cooler air into engine compartment.

[Trackrig]

Part of what the OP's posting shows is that your dash gauges can be wrong, or at least off. It's cheap to get a Scangage D for about $160 to verify your dash gages. And the Scangage will pick up other readings that you don't have gages for such as the transmission temp and the intake air coming into the engine. If the intake air goes up and you're in hot weather in the hills, the engine temps will start rising shortly afterwards.

As for the length of the slobber tube, mine is out several inches past the radiator.

Another last resort type fix is plumb in a large transmission cooler with a fan someplace, only instead of to the transmission, connect it into the engine oil. Both the oil and water temps are directly related, if you cool off the oil some, you also cool off the water.

Bill

[sevenmacs]

I thought since fan forces air through it should still draw enough air. Opening side closure strips can be done easily , so I may experiment and try it. But your right about introducing cooler air into the engine compartment somehow. Possibly a louvre on drivers side battery compartment that adjoins engine compartment . I've seen some MH's with a louvred door on drivers side with a rear radiator. Just finished a trip through mountains and temp got to 221, outside temp was 85-90, grades weren't that bad just long, high teens were seen frequently. But I was cresting top at 60 to 70mph, slower may reduce temp. We usually travel in fall and spring so this is my first experience at summer high temps and mountain passes. So I assume it's just how rear radiators perform. I've cleaned radiator several time and changed stats, as well as flushed system all recently.

[Wroughtnharv]

We pulled out from Camp Verde on 260 heading up the mountain to Happy Jack AZ. 260 has some pretty good grades and on some of them we got down to low forty mph' so. The ambient was 100 degrees or better, late afternoon.

I had to stop once when it got up to 250. I idled it up to about 2000 and it cooled down quick enough to 190. I went on up the mountain and it stayed between 220 and 240.

Ten days later I came down the mountain. We were at 6,800' above Happy Jack, went down to about 6,000' then back up to 7,450, and then back down to Camp Verde, 3,300'. She overheated big time coming down. She pegged the temperature gauge and I saw a huge steam cloud in the rear view camera. I let it cool down but the rest of the way down she stayed at 240 to 250.

One of the hardest things I've had to do in my life was pull the dipstick in Camp Verde. I just knew there would be water in the oil. There wasn't. But what I did find was the radiator cap was loose. I blamed myself because I had topped off the oil and water before we headed down the mountain. It was obvious I had forgot to tighten the radiator cap on correctly, old age strikes again.

The trip up and down the mountain we had the Casita travel trailer in tow, Dad's off grid apartment.

Last Sunday morning we left Camp Verde for I 40 in Flagstaff via I 17. We got to 210, ambient was cool. We stopped in Moriarty NM and she had ran 180 to 190 all day. Yesterday morning we left Moriarty and arrived in Graham TX last night. All day long she kept getting hotter. First it was up to 190, then 200, then 210, and by the time we stopped last night it was 220. Slight grades if any, mostly down hill.

We're at the Eddleman Lake camp ground and I found the problem. The radiator cap had backed off again. I'll look at it closer at home east of Dallas to see if I can figure out what is happening. The cap is a new cap that I purchased before the trip at OReilly's. I took the old one down to the store and them gave me this one as the replacement.

93 Winnabego Vectra 35' RQ 5.9 Cummins 6 speed Allison approximately 130,000 miles

[Wroughtnharv]

We pulled out of the campground and within 3 miles it was hot, again. We probably got about seven miles with me pulling over and letting it cool off for awhile and then it get hot again, talking 240 to 250.

Finally I sat down and went over everything that had happened. The big thing was the overflow tank contents hadn't moved and were hot but not hot enough to burn. So I let it cool down and then removed the cap. We added about two and a half gallons of water to the radiator and then hit the road again. All kinds of traffic, speeds up to seventy, and she sat there at 180 like it was the right thing to do.

We made it to the infusion appointment just five minutes late. One of the good things is I have a line on a local that is a retired diesel mechanic that said he would work on the 5.9 for me if I cleared the bed etc for access. That will happen next week or so. Plans are a water injection system into the radiator shroud to cool off the air going into the radiator when overheating begins. There are some other things but we will see what time and the budget allows.

[Rich-n-Linda]

Direct from Cummins...220 is hot, but OK. Damage starts at 230. You should never get anywhere near 250!

I hope you have not damaged something deeper in the engine with your excursions into the 250 degree area.

[Trackrig]

Seriously, you need to change your oil also. I talked to a Mobil One synthetic oil engineer last year. He said Mobil One, a synthetic oil can handle 250 deg for 30 minutes and 270 deg for only 2 to 3 minutes before breaking down.

If your water pegged at 250 deg then your oil was hotter and I doubt you're running synthetic oil.

On the rig I called him about the temps on, I now also have an oil temp gauge and it runs hotter than the water temp.

Bill