Land Yacht 33 Chevy How to keep your engine from getting Hot.

[shaneteck]

Hello all.

I have a 95 Land Yacht 33 with the GM P30 Chassis. I bought it used a couple of years ago and live on the west coast which means just about any direction I go in, it involves crossing a hot desert in the summer time.

Our first trip back in 2008 up to Yellowstone was in June and although it was quite cool in Yellowstone, traversing Nevada and Utah pulling grades on I15 I was experiencing temperatures (on the gauge) approaching the "red zone" with ambients in the 115 degree F range.

Upon inspection it became fairly evident that as with most motorhomes not a great deal of effort was spent trying to seal off the grill area to the radiator. I spent some time with a bit of aluminum angle and some aluminum sheet from the hardware store, along with some pieces of rubber mudflap. I fabricated up a shroud which seals the grill to the top and sides of the radiator. Next I went inside the engine compartment and created inner panels to seal the engine bay from the fenderwells so that all of the air coming through the radiator then had to pass over the engine and exhaust.

I finally had a similar test this weekend 4th of July trip into Arizona with ambient temperatures of about 105, never saw the gauge move over 210

As an added measure of protection however I also installed a water spray kit which I can manually turn on and off with a switch from the drivers seat. I used the connection from the rear of the coach with the water spigot for the sanitation tanks, and ran a 50 foot hose to the front of the coach. I installed 6 Misting Nozzles into a PVC tube across in front of the radiator/coolers and a solenoid valve connected to a momentary switch on the dash. Just for kicks I switched the water on while climbing a grade with the engine at 210F. After only about 1 minute of the water spraying on the radiator, the temperature had dropped down to the thermostat at 195F!

Just thought I'd share the idea here with others.

[HowieE]

While you have designed what the factory should have I would offer some additional suggestions.

A unit that is 15 years old should have the radiator pulled out and rodded and cleaned to renew it capacity. I pulled mine about ever 3 years on my 87 and 97 trucks.

I would also suggest an after market temperature gauge as the factory one are not known for accuracy.

[Harleyjohn]

Greetings All,
I'm a "newby" as we recently bought a '92 33' Land Yacht. (May 2010)
I thought this 'spray' system was a great way to beat-the-heat problems with summer use of a large motor unit.
However, when I talked with my very knowledgable mechanic, he said this has been an age old solution for diesel users and since mine is a gas engine he cautioned me about the gas units having spark plugs and wire harnesses and the potential of misfiring issues. -FYI-

[shaneteck]

Your mechanic is absolutely correct about the possibility that water on electrical connections could cause problems.

However, in my installation I used misting nozzles which break the water into small droplets so there is no direct stream of liquid water entering the engine bay. I also use the water when the temperature exceeds 210 or thereabouts, giving the chance for the temperature to change the liquid to a gas as it removes heat from the radiator. I have noticed no signs of water intrusion under the doghouse after using the system and my suspicion is that I am injecting less water into the system than it would otherwise see while wet weather driving. I have experienced no ill effects to running the water spray system with regards to missfires.

Certainly if you inject water onto the plug wires and it creates a missfire it is not a good thing but in reality that is a problem with the plug wires or the spark plugs which should be replaced anyway.

Regards,
Shane T

[DaveFL]

How did you calculate air flow away from the motor? I would like to do the same but not for heat but isolating motor from critters. I can see where panels could be installed to the frame on either side forcing the air to continue back over rear of engine and across transmission. Did you measure opening at radiator and space at back of engine? and did they match?

[Jim Foster]

Originally Posted by shaneteck

Hello all.

Next I went inside the engine compartment and created inner panels to seal the engine bay from the fenderwells so that all of the air coming through the radiator then had to pass over the engine and exhaust.

I finally had a similar test this weekend 4th of July trip into Arizona with ambient temperatures of about 105, never saw the gauge move over 210

I think I would have omitted the panels to force the air over the engine and exhaust.

In building Street Rods, we have many of the same problems regarding air movement through the radiator. The "funnel" you created to force the air through the radiator is exactly what we try to achieve. However, after the air has done it's job through the radiator, we let it exit as fast as it can, so as not back up and keep air from coming through the radiator. That's what louvers on the sides and tops of hoods on Street Rods are all about. Get rid of that hot air ASAP.

Just a thought.

[Dave Park]

You can also get an increase of cooling capacity by changing your coolant to a different blend.

By using more water and less anti-freeze, then adding a surface tension modifier (basically a detergent) like Royal Purple Ice Radiator, Redline Water Wetter or similar. This'll improve heat transfer, which is equivalent to increasing the capacity of your cooling system.

I use this in my tow vehicle and under load, it always runs 15-20F cooler than before I change over. I always do a full flush before changing over.

[timmac]

To the the OP on driving a motorhome thru Nevada during 110+ degrees is not a good idea even if you do all the mods as stated, I live here and many folks that drive thru here in the summer do experience the same problems, yes some do OK but most run hot, if you have to travel thru here in the summer do it early in the morning or after sunset, the desert summers are just damn hard on motorhomes..

Just my 2 cents..

[YACHTSTER]

cut your losses get a cummin. .in south la. cant run 454 made my nerves crazy got 94 ly /cummings OOOOOOOOOO YEAH 180 DEGREES