-
Block Heater
I posted something about the block heater awhile back about the hissing, Today I removed the aux oil tank and in that same rear little door is the plug for block heater, after removing tank I made a bracket for block heaterplug. In doing so I pulled wiring for block heater out and found a bare spot in wiring, replaced wiring and now it pulls 10.5 amps before it pulled 8.8 amps, something changed.
-
9 Replies
-
Wow! I had to read it twice. First time I thought that the bus was repairable; second time apparently only the bus barn was repairable. Bus is gone.
Don’t have a bus … yet. But learn something everytime I read a post.
Does the block heater heat the oil or the water in the water jacket? On cars and light trucks the “block heater” typically installs in a freeze plug … aka freeze plug heater.
If you’re been around race cars you’ve probably noticed that they often preheat the oil … especially the more expensive faster cars with high HP motors. At the NASCAR events you’ll see them pushing the car down pit road all in a line waiting for their turn to qualify. The crew is normally pulling a small generator along that is plugged into the oil reservoir (they usually carry 4.5 gallons or so in a 7.5 gallon oil tank behind the driver. The 110v lines from the genny are plugged into either straps around the tank or probs sitting low in the tank to heat the oil. There is a mechnical oil temp gauge on the tank with its prob in the oil to monitor oil temp.
When I bought my Cup car from Junie Donlavey, his shop foreman Ken Bell cautioned me about letting the oil heat too long. They set my car up with two straps (one high and one low). Ken told me that on the tanks with probes that they’d pull the probes out and they all be “coked up” from the probe and the oil that got awfully hot.
About the third year I had the car I was going to start it one evening. Came home from work, plugged the oil in, and started to do some work on the car. I got distracted with a phone call and eventually realized that the oil must be HOT because I could really smell it. As I pulled the plugs on the oil tank the needle was WAY over the top number on the gauge (which I think is 280 degrees). I use Joe Gibbs Racing Oil so I called their field engineer, Lake Speed Jr (yes son of that “Lake Speed” and no relation to Scott Speed). We thought it got to 325 degrees. He said that the qualifying oil is heated to around 300 (probably more), but that isn’t the normal racing oil. He thought I “should be OK” running the oil going forward. I thought about it and decided to dump it and spend $250 on a an oil change as insurance against damaging a $20,000 engine.
Then we started to crew on an ARCA stock car team. I noticed that many of the teams had a box that that was sat between the generator and the oil tank with a probe in the tank. Knob or two, switch, and digital readout. Set the desired temp and when it was reached … the 110v point to the tank was cut off until the oil cooled down. Shouldn’t have to worry about over temping the oil.
Now … back to the Prevost.
How is the “block heater” wired and hooked up? Is there an over temp feature that cuts off the power when the engine gets hot enough? Is oil or water or both being heated?
Automatic on board fire extinguisher. I wonder if that would have saved this bus.
-
If the oil caught fire it must have been a pan heater block heaters on a 60 series will take a day for one to heat to 150 degrees mine had Woods timer to set 2 hrs was the max setting fwiw that is to bad you hate to see that happen to anyone
-
I’ve only had three coaches, but they all were in the cooling jacket. Now I only use the Webasto for a preheat and that is coolant.
Pan heaters are dangeous, and they have hot spots on the pan that damages the oil.
-
2004bus,
Any idea what type block heater he had? Like Jon, all of mine have been coolant jacketed and I’ve used every one of them. If you could get more info, that would be great.
-
I ran my coolant block heaters (1kW each) on the boat diesels (625hp 6v92TAs) 24/7 for 5 months of the year. No problems other than the electric bill. Those babies were so high-strung they needed all the help they could get.
Hard to believe you can hurt a bus diesel with a properly installed block heater (coolant-type).
Even a pan heater should be ok. The common electric oil-filled radiator heaters for home use contain much less oil and at the 1.5kW setting you cannot burn yourself on the fins.
-
I guess the block heater could short and then create a problem,but I would think that the breaker would trip.
-
I asked him if he had a pan heater and he didn’t know, he thinks it’s just a block heater. What I found scary was the inside explosion. I don’t remember the term he told me the inspector used but 3 slides were out and it blew them out of their channel and blew out the windshield. I’ve been around a lot of cold weather trucks and I never heard of a pan heater. We put charcoal under the pan and lit it. The good old days.
200 gal of fuel on board, didn’t burn.
Later
bv
-
It’s possible there was somethng else going on. Having had the unpleasant experience of a fire in the engine compartment I know for certain that there has to be a lot going on before a fire associated with anything in the engine area is ever going to pentrate into the house. Our fire was freon fed, burned 10 batteries to ash and despite it being directly beneath and behind the closets and bed, not even an odor pentrated the coach.
For something to have gotten into the house, and then exploded with such force to blow the slides out it sounds like the engine might have been the victim and not the cause.
-
no glass blown out and it was massive— his had another fuel source for explosion. Mine didn’t burn thru floor.. woulld have taken building down if it were inside (my fire that is)
Log in to reply.