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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: chessie4905 on July 23, 2019, 11:08:08 AM

Title: Engine overheat on hills
Post by: chessie4905 on July 23, 2019, 11:08:08 AM
Engine overheating.
After reading Olrunt's thoughts, I started thinking about heating issues on hills on many of the conversions here. How about adding a large squirrel cage blower to the engine compartment and have it exhaust the hot air out the back or rear side of coach? It would be 110 volt, probably two or three horse power and would draw off inverter or generator. Just used for climbing grades, could be triggered by relay and adjustable temp sensor in water jacket. Could also have an override switch for full on, and would be useful to cool engine compartment at end of day if needed. Use a tefc motor with sealed ball bearings.
Comments?
Title: Re: Engine overheat on hills
Post by: lostagain on July 23, 2019, 11:27:22 AM
In my MC5C with 6V92TA, I removed the bottom floor pans years ago. That improved cooling. The air, forced down off the squirrel cages, flows down past the front and sides of the engine, and out the bottom easier.

JC
Title: Re: Engine overheat on hills
Post by: Jim Eh. on July 23, 2019, 12:44:36 PM
What about replacing the floor pans with louvered ones to actually create suction?
Title: Re: Engine overheat on hills
Post by: DoubleEagle on July 23, 2019, 06:41:44 PM
I've toyed with the idea of using the coach A/C fan (minus the A/C parts) to exhaust air out since the radiator fan draws it in. I don't know how well that would work with the coach in motion. Has any one tried that on an Eagle or any other coach? Setup's that blow the air down to the ground stir up too much dust on dirt roads and campgrounds.
Title: Re: Engine overheat on hills
Post by: chessie4905 on July 23, 2019, 06:47:26 PM
The GM one is pretty massive. Only issue is how far forward it is. Extra plumbing and add a coolant pump of sufficient volume. I don't  think the factory one would move enough coolant. The havoc main coach heater core is pretty massive. Maybe rework the ducting to blow down to ground. Shouldn't  be an issue on the highway.
Title: Re: Engine overheat on hills
Post by: Glennman on July 23, 2019, 09:47:15 PM
My '74 MCI has a massively customized radiator system that consists of (besides the 2 factory radiators on the sides) 2 additional MC-5 radiators mounted horizontally across the top of the engine compartment where the squirrel cages used to be. They each have about a 60 amp fan sitting on them sucking (hot) air through them upwards from the engine compartment, through the radiators, and into the area where the squirrel cages were, and out the back (I have the rear upper door off at this time). The side factory radiators each have about 40 amp fans on them blowing through the radiators from the outside into the same area again as the squirrel cages. These also have on each of them a scoop mounted on each side of the bus at the screened area scooping air into the factory radiators.

All this being said, I wish I had the original system. The fans all run while climbing hills, and the bus gets to about 210 degrees or so (I don't really recall right now), and I'm pulling over for it to cool down. It cools down extremely fast, but the hot air really doesn't have anywhere to go. I'll be visiting this at some point in the future.
Title: Re: Engine overheat on hills
Post by: silversport on July 23, 2019, 10:02:56 PM
12 mister heads in front of radiator tied into the fresh water with a switch that turns on the pump and electric valve works great. Will drop the temp 10 + degrees even while still pulling a hill. Also put an idiot light on the dash so I do not forget to turn it off a the top of the hill and lost all the water.   
Title: Re: Engine overheat on hills
Post by: Bill Gerrie on July 24, 2019, 05:36:47 AM
While a rear engine bus is hard to cool at the best of times the pans according to the MFG's literature add about 20% to the cooling. The newer dimpled tube rads are a great addition as they cool about 30% better then the original ones. Expensive fix, Yes, but it works. The engineers spent many dollars and time to designed these coaches to cool so not much else we can do will work any better then the original design. Misters will work when the engine gets too hot and you need to bring it to a safe temperature quickly. 210 is a way too hot for a Detroit. Chance of cracking a head is just around the next corner.
Title: Re: Engine overheat on hills
Post by: luvrbus on July 24, 2019, 10:35:22 AM
Quote from: Bill Gerrie on July 24, 2019, 05:36:47 AM
While a rear engine bus is hard to cool at the best of times the pans according to the MFG's literature add about 20% to the cooling. The newer dimpled tube rads are a great addition as they cool about 30% better then the original ones. Expensive fix, Yes, but it works. The engineers spent many dollars and time to designed these coaches to cool so not much else we can do will work any better then the original design. Misters will work when the engine gets too hot and you need to bring it to a safe temperature quickly. 210 is a way too hot for a Detroit. Chance of cracking a head is just around the next corner.

Or this melted liner seal rings on a
8V92 a rag in the cooling system caused this not a drivers error,a rag in the cooling system cost this guy a engine 
Title: Re: Engine overheat on hills
Post by: Bill Gerrie on July 24, 2019, 11:06:40 AM
With the cost of rebuilding these engines a rag left in the cooling system would be an unforgivable error. I hope the guy stepped up to assist in the cost of the repair. Accidents do happen but can be costly to say the least. 
Title: Re: Engine overheat on hills
Post by: chessie4905 on July 24, 2019, 11:18:52 AM
Most likely FAT CHANCE.
Title: Re: Engine overheat on hills
Post by: luvrbus on July 25, 2019, 03:30:52 AM
This is what a liner looks like after the shop rags in the cooling system
Title: Re: Engine overheat on hills
Post by: Bill Gerrie on July 25, 2019, 06:26:45 AM
That does not look good. It looks like they weren't that old with the crosshatching still on the liner. What a shame.
Title: Re: Engine overheat on hills
Post by: luvrbus on July 25, 2019, 06:30:19 AM
Quote from: Bill Gerrie on July 25, 2019, 06:26:45 AM
That does not look good. It looks like they weren't that old with the crosshatching still on the liner. What a shame.

I may have to bore this 92 series to save the block,Bill it took for ever to remove 2 of those liners I finally had to dig out the puller to remove the 2 
Title: Re: Engine overheat on hills
Post by: Van on July 25, 2019, 12:34:48 PM
Quote from: luvrbus on July 24, 2019, 10:35:22 AM
 

Or this melted liner seal rings on a
8V92 a rag in the cooling system caused this not a drivers error,a rag in the cooling system cost this guy a engine

   Jeez Cliff, I wonder if some fabric softener additive would have softened the destruction? :( The owner must be devastated, Bet the poor Sap never saw this coming. I'd be willing to help out, lemme know if there is anything I can do? ;)
Title: Re: Engine overheat on hills
Post by: chessie4905 on July 25, 2019, 02:38:02 PM
Are you talking about a bore job or honing the bores to the next oversize?
Title: Re: Engine overheat on hills
Post by: luvrbus on July 25, 2019, 02:50:34 PM
Quote from: chessie4905 on July 25, 2019, 02:38:02 PM
Are you talking about a bore job or honing the bores to the next oversize?

92 series liners just come in .10,.20 and .30 oversize they are not like a old 71 series,honing want get it
Title: Re: Engine overheat on hills
Post by: chessie4905 on July 25, 2019, 02:54:40 PM
Do you have to send the block out? And have it magnafluxed or whatever they may use now? Man, that sucks for the owner. Any possibility that rag was in there before last rebuild/repair and that guy didn't  notice it.