Plastic Engine Fans

kevink1955 · June 22, 2010, 08:16:07 PM

I do not know if anyone has plastic cooling fans on any of their engines but I am posting this as a warning.

In the last year we have had 2 fans throw blades on our Series 60 detroits on our fire appratus. The first one was about a year ago and we got lucky and it did not damage the radiator. Yesterday another one broke and it ate the radiator. These trucks are tilt cabs and to get to the radiator there is lots to remove, the truck will be OOS at least a week.

The fans are a light tan color and are directly driven (no clutch)

Our shop has checked with several other shops and this is not the first time this has happened. The trucks are about 10 years old.

JohnEd · June 23, 2010, 04:33:27 AM

Kevin,
Great info! Thank you. Do you know the mfr or is it just on DD60's? I would replace the thing, if I had one, on little else than your report.

A long while ago there was a discussion here about fans and cooling and efficiency. The HP needed to run the fan was established and the actual cost of running it in terms of MPG. It wasn't insignificant but I don't recal the number. Putting on a fan clutch was worth the time and trouble, as was installing a shroud, as was getting rid of the "old school" metal blade thing. The replacement fan was described a "aerodynamic and efficient" and was plastic. I doubt that the 60's ever came with a metal blade but I have no doubt that one is made for it. Move to a better manufacturer or design I can see but I wouldn't throw away the advantage of an efficient fan. And I didn't hear you say that any should go "heavy metal"..

John

kevink1955 · June 23, 2010, 04:13:39 PM

John

I will stop by the shop Thursday and see if I can find the manfacturer, I am not sure if Detroit supplyed them with the Series 60 or the fire appratus manfacturer did.

Thinking back we also had a metal fan chuck a blade on a 30kw onan gen set about 8 years ago, it also ate the radiator. In that case it was a pusher fan and we were told that air flow restriction on the outlet side caused the failure by making the fan flex.

Never bought that one and when we checked a similar unit that had no external ductwork we found that one cracked also.

It's an expensive mess that I would not want to see anyone go thru.

Ed Hackenbruch · June 23, 2010, 06:32:59 PM

Many, many moons ago i worked for Weyerhauser building logging roads with a D8 dozer and started hearing a subtle noise change in the engine. Stopped several times to check it out and finally found that the fan bearing was going out and the fan was close to going thru the radiator. A few years later i was working for a construction company running a smaller dozer and once again i could hear a different noise than normal. I once again checked it a couple of times and could find nothing wrong and kept running it and thinking about it. All of a sudden i remembered about the D8 and stopped and checked the fan....same thing, she was coming loose. Called the mechanic and told him, he came and checked it out and asked me how i had figured it out so i told him about the D8. He said most people never would have caught it once much less twice, said i had saved the company a lot of money. Any time after that if i told him i was hearing a noise on a piece of equipment he would come check it out asap.

Ed Hackenbruch · June 23, 2010, 06:36:13 PM

Ps. that is one of the reasons i do not drive any rig with music on.....i am constantly listening for either new little noises or changes in regular noises. Has kept me from having major problems more than once.

JohnEd · June 23, 2010, 06:58:57 PM

Ed,

Great story and lesson. Birds of a feather...sorta. I do drive with music as often as I can. I also make it a point to listen to the engine when I start it and while it is running along and when it is pulling hard. That is something that has stuck i my craw since I first started thinking about a bus I can't really hear the engine and I am getting progressively more hard of hearing. My thought was a microphone in the engine bay, weather [proofed naturally. That driving a speaker up near my head in the cockpit with a momentary switch. That might be far fetched but stories like these certainly bring it back towards rational.

Kevin,

You can save guys a ton of money by relating these experiences. You know that, obviously.

Thank you both

Ed Hackenbruch · June 23, 2010, 07:29:06 PM

John, i have a 30-40% hearing loss in my right ear thanks to the US Army and Vietnam. Probably 20-30% in the left ear due to the same and years of running equipment before the days of earplug usage. Have had tinnitus for 40 years now so i need to have it as quiet as possible to be able to hear my engine.

JohnEd · June 23, 2010, 07:42:47 PM

You have described my profile. The VA coughed up $7K for my aids and they are terrific. I can start going back to the theater and watching some of my old favorite TV programs. Now if they could just grow me a new......... belay my last.

Wrong forum....SORRY! (and I mean that)

John

Len Silva · June 24, 2010, 08:36:06 AM

Quote from: JohnEd on June 23, 2010, 06:58:57 PM
Ed,

Great story and lesson. Birds of a feather...sorta. I do drive with music as often as I can. I also make it a point to listen to the engine when I start it and while it is running along and when it is pulling hard. That is something that has stuck i my craw since I first started thinking about a bus I can't really hear the engine and I am getting progressively more hard of hearing. My thought was a microphone in the engine bay, weather [proofed naturally. That driving a speaker up near my head in the cockpit with a momentary switch. That might be far fetched but stories like these certainly bring it back towards rational.

Kevin,

You can save guys a ton of money by relating these experiences. You know that, obviously.

Thank you both

Here comes the tinkerer again. Some genius here could come up with the microphone in the engine compartment hooked to a computer with "voice recognition". After learning all the normal sounds of your engine, it could detect any abnormal noises.

I have the greatest ideas

, just not the ability to carry them out.

JohnEd · June 24, 2010, 10:16:38 AM

Len,
With today's current crop of techies I'll bet that VRS is right there with your idea. Your watch.

John

kevink1955 · June 24, 2010, 08:30:02 PM

I was in the shop today and looked at the fan, I could not find a manfacturers name or logo anyware on it. It may have been on one of the missing blades.

When the replacment arrives I will attempt to get a look at it before it is installed for a name. It's coming from the fire appratus manfacturer and it will be plastic, they say that steel is not avaiable for the S60 engine.