Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 08, 2025 ...

Wash Engine Bay ???

January 16, 2025, 01:17:57 pm

I replaced  the compressor coolant inlet tube that sprung a pin hole leak last week. It was my time to get in the engine bay since acquiring the coach last year and it's definitely dirty and could use some TLC and a good cleaning .  Is it advisable to to use a degreaser and gently power wash the engine and engine bay?  If so, how ?  Thanks all!!

2001 U320  4010

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Re: Wash Engine Bay ???

Reply #1 – January 16, 2025, 01:41:01 pm

If you have a air compresor get a gallon of mineral spirits and a air powered syphon gun ,that will clean oil and grease,if the crud is baked on you may need to scrape and brush and use oven cleaner,if it is only light oil you may get by with a water soluble degreaser and a hose,either way when done blow off all moisture with air.

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Reply #2 – January 18, 2025, 01:40:39 pm

As John posts, a water soluble degreaser with a siphon gun and compressor. I use about a 50/50 mix.  Best on a warm engine. If you do this every year, you won't need a oven cleaner and scraper. Let water/degreaser mix sit for a few minutes and them repeat.

With a clean engine, you can spot any new leaks quickly.

Don't use a car wash gun on a running engine. Yes, some do!

Pierce

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Reply #3 – January 18, 2025, 01:58:14 pm

If using a degreaser such as Simple Green, be sure it's a version that's is okay for aluminum.  Regular Simple Green is not.

Simple Green - SMP13406 Extreme Aircraft and Precision Cleaner, 1 Gallon...

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Reply #4 – January 18, 2025, 02:17:14 pm

So many like a pristine engine compartment. Me too, BUT pressure washing will induce water into places it normally would never go driving down the road. Water will lead to corrosion. The dirty crummy engines always come apart and the clean spotless one will have fasteners that are frozen in. Seals will pass water under pressure and all you will know is that it's clean till bearing failure. Mineral spirits will remove excess grease and will eventually dry out but it stinks. Absolutely use a cleaner designed for aluminum and magnesium. Ive seen tens of thousand of dollars spent repairing corrosion induced by cleaners. I have a 4500 psi pressure washer and a 22hp hot water steam pressure washer and have never used either on my engine. Just saying. They have there place but I prefer to use on parts with no moving parts, wiring,  or anything requiring lubrication.

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Reply #5 – January 19, 2025, 05:09:05 pm

So you would recommend leaving well enough alone??? I can live with that.  It has 180k and runs great!!  I don't want to cause a problem. Thank you for your input.

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Reply #6 – January 20, 2025, 10:39:15 am

Reply number 4 forgot one thing,you have to use common sense,I spent 30 years washing industrial engines and never had
any of the above disasters,never had a nut and bolt that was "frozen" or water past a seal,for those of us that work on these
engines I would rather work on a clean one that a greasey one.If you are trying to find a leak washing is a must,if somehow
fasteners will get frozen what do you think happens when it rains.At some point the oil and grease will effect cooling and spill
on to other components,after washing start the engine and in afew minutes it will be dry and if there are some areas like linkage
that need oiling just reoil them.

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Reply #7 – January 20, 2025, 01:16:55 pm

I worked on Tuna boats for 37 years then ocean going Tug boats for 8 more years and always washed the engines down with soap and water. Understand, you must be carful of how one uses a hose when washing any engine with soap and water.
 And like John said, run the engine after washing to dry it off. You just have to be carefull.

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