Skip to main content ↑ ↓
Topic: Engine Fan on 91 GV (Read 937 times) previous topic - next topic

Engine Fan on 91 GV

I am replacing all coolant hoses and anything else that I can address under the coach this weekend.It dosn't look easy but i'll get er done. I was checking out my engine fan and took a picture. It is black I read about issues with the blades coming apart on some. There are no cracks or chips gouges etc anywhere on the fan .Does anyone know if I have one of the problematic blades by looking at these pictures?
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Engine Fan on 91 GV

Reply #1 –
Nope that's the same fan I have on the 92, I have heard the same stories and have had no issues as of yet. With any good pre trip/ post trip should be able to spot any problems. Just my thoughts.
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: Engine Fan on 91 GV

Reply #2 –
Can't see too well, but yours looks like mine on our 91 GV.  Mine has metal blades.  I believe that the newer rigs have the plastic blades, not sure what year it all started.  Have a great day  ----  Fritz
Fritz & Kathy Johnson
1991 36'

Re: Engine Fan on 91 GV

Reply #3 –
Stump,
Our coaches are the ones you need to be concerned about.  Original fan has fiberglass blades and are the ones you need replace.  Replacement fans will have plastic blades.  On the fiberglass ones you can usually see the fibers on edges and anyplace there are nicks.  If you can't tell by looking I would scratch a surface or edge and look for the fibers.

Fan belt is very easy to adjust, just not so easy to get into the area.  Four bolts (3/4" wrench IIRC) lock the fan base hub down and another vertical bolt is used to move the base up and down for adjustment.  A 3/4" socket with long extension is what's needed to reach the adjustment bolt from the top.  You will need to lay on top of the engine.  I throw some towels down over it to cushion and keep me "clean".

P.S. You need to inspect your radiator core to see that the fins are not becoming detached from the tubes.  In you photo I can almost see some areas that look suspicious to me.  Not an emergency if you find some detached but and indicator that you won't be getting maximum efficiency and a new core will be required in the future.  Obviously keeping the fan side of the radiator clean is important and these rear radiator units are susceptible in this regard due to sucking air over the engine.  The cleaner you can keep the engine the better for this reason.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Engine Fan on 91 GV

Reply #4 –
You definitely will NOT be able to spot damage with pre trip / post trip examinations, even if you're the manufacturer of the fan blade. Theirs exploded on the way to a trade show after their engineers carefully examined it knowing full well it was a fiberglass blade and it would eventually explode. That's not a metal fan blade, but I can't tell if it's fiberglass from the photo. If it's a nylon fan blade you're okay because a previous owner has already changed it. You can feel or see the fibers in the fiberglass fan blade if you rub it.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: Engine Fan on 91 GV

Reply #5 –
Quote from: JohnFitz –
Stump,
Our coaches are the ones you need to be concerned about.  Original fan has fiberglass blades and are the ones you need replace.  Replacement fans will have plastic blades.  On the fiberglass ones you can usually see the fibers on edges and anyplace there are nicks.  If you can't tell by looking I would scratch a surface or edge and look for the fibers.

Fan belt is very easy to adjust, just not so easy to get into the area.  Four bolts (3/4" wrench IIRC) lock the fan base hub down and another vertical bolt is used to move the base up and down for adjustment.  A 3/4" socket with long extension is what's needed to reach the adjustment bolt from the top.  You will need to lay on top of the engine.  I throw some towels down over it to cushion and keep me "clean".

P.S. You need to inspect your radiator core to see that the fins are not becoming detached from the tubes.  In you photo I can almost see some areas that look suspicious to me.  Not an emergency if you find some detached but and indicator that you won't be getting maximum efficiency and a new core will be required in the future.  Obviously keeping the fan side of the radiator clean is important and these rear radiator units are susceptible in this regard due to sucking air over the engine.  The cleaner you can keep the engine the better for this reason.

I don't see any fibers. it's a pretty thick blade, I looked it all over and did not see any signs of looseness on any blades. I called Foretravelparts today about the lower Rad hose availability,which it isn't by the way Discontinued. I asked him some questions about the fans and he ''said basically he didnt sell that many replacments . He said most of the issues are when someone runs over a piece of tire rubber,''gator' as we call it in the trucking world and the tire flips it up If the Fan is engaged it could/Can suck it up into the blades. He said from his experience most failures have been from objects entering the blades and not the fault of the design.I firmly believe a good pre/post trip inspection would hopefully raise an eyebrow if I saw something that didn't look right such as nicks gouges etc. Stay away from stuff in the road.
 The fins behinf the fan are scuffed some, This engine was replaced in 2000. By Branson Motorcoach ,in Mo. The engine was a remanufactured unit by Diesel Exchange in Springfield.I have contacted both trying to get an odometer on when it was installed,but the old records are long purged. Diesel exchange has the invoice info and the original engine was dusted meaning run with a faulty air cleaner system wiping out liers turbo etc.
 The coach has 129,000 on it and the owner I got it from only put about 5000 on it when he parked it, When he bought it it had 124,756 on it I divided that by 17 years which is 7338 a year then I figured it got the new engine in 2000 so 7338x9yrs =66042. 129,000 now minus 66,042 est=engine should have  roughly 63,000 on it,If  these engines will run as many miles as I know they will,Way AFTER i'm on the other side ,This will still be screaming up and down the hiways as long as diesel is still around,Hell by then we might have figured out the flux capacitor and have it run on beer cans,and peanut shells! I could have Betsey drive then and I could sit in the back and Make Fuel!!!!LOL
 Talking to the Tech guy at Gates rubber today concerning my lower hose he really educated me about the right hose choices and as before I was looking at silicone he strongly recommended Gates green stripe EPDM instead, Somewhat cheaper and a better fit for my application. So I'm going with all Green stripe Gates hoses. I  Found rolls on amazon free shipping,Will be here next week,now to start pricing six tires! !, This thing is gonna be the SH*t Diggity at bikeweek this year,I'm saying NO to hard ground and a tent!!!
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Engine Fan on 91 GV

Reply #6 –
If it has high silicone hoses on it currently you probably don't need to replace them. They're supposedly good for life. I didn't replace any of mine even when I had them all off for the radiator rebuild. They still looked great after 20+ years.

For the benefit of other readers let me stress again that even the manufacturer of the fan was unable to detect any defect in the fiberglass fan on their company motor coach before it exploded and took out their radiator on the way to a trade show. They knew full well it was a fiberglass fan and that it would eventually explode, but they didn't have time to change it to a nylon fan before going to the show, so they had their engineers carefully examine it... and it blew up anyway.

Foretravel has had at least two fiberglass fans explode on their coaches at the factory. One of them was being driven by their parts dude at the time it blew up. He told me he saw the temperature gauge climb suddenly so he shut down the engine and went to see what had happened. When he opened the bed a fiberglass blade was sticking out of the bottom of the plywood bed. He called the factory because he was only a few miles down the road, and they towed it in. In this extremely rare case the radiator didn't get destroyed. The other time they blew up the radiator though... If this happens to Foretravel, happens to the manufacturer of the fan itself, and happens to MEEE!, why won't it happen to you? You have been warned but I didn't have that advantage unfortunately. :(
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: Engine Fan on 91 GV

Reply #7 –
Stump,

Excellent detective work on an antique rig!  Just make double sure you have plastic fan blades like John and Scott have advised.  Scott had an awful time when his exploded and many shops may not want to work on a rear radiator model.  You don't want that.  Please read his posts and experience on this subject and you will find out what out what an ordeal it was.  Since you're way ahead of the $money game on this one it would be much cheaper to replace the blades now than to possibly have your radiator damaged beyond repair and to have to replace both on the road.  That kind of stuff can take all the fun out of a road trip.   

Jerry
The selected media item is not currently available.
Jerry and Cindy Maddux
1993 U300/36WTBI DD6v92TA
build 4271  "Miss Lou"
1995 suzuki sidekick 4x4 toad
Gulfport, Ms

"Pride of Ownership"

Re: Engine Fan on 91 GV

Reply #8 –
Quote from: stump –
I called Foretravelparts today ... asked him some questions about the fans and he ''said basically he didnt sell that many replacments . He said most of the issues are when someone runs over a piece of tire rubber,''gator' as we call it in the trucking world and the tire flips it up If the Fan is engaged it could/Can suck it up into the blades. He said from his experience most failures have been from objects entering the blades and not the fault of the design.
Back in 2001 when I was in to service other things at Foretravel it was the service advisor that suggested I replace the fan due to the exact experience Scott had - takes out the radiator too.
I suppose this is one of those things where you will get a difference answer depending on who you ask.  It's hard to expect the folks at Foretravel to remember the particulars of a component that was last used on coaches 23 years ago ('91 was the last year of rear radiators on the U300).
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Engine Fan on 91 GV

Reply #9 –
I Agree Fellows I just don't know if it's already been replaced, Thats why I posted the picture. Is it the good one or the bad one?
This is all new too me,But I Own and operate a semi truck daily over the road and maintain my equipment myself,So I'm trying to learn. if it needs replacing no problemo!! :D
91 GV U300 Unihome 40' Build 3811
6V92TA Detroit

Re: Engine Fan on 91 GV

Reply #10 –
I looks like a good one, I'm sure theses guys will know
Andy & Eileen
MONTROSE COLORADO
1992 U300  40' 6V92 TA
2016 4 Runner
1998 Jeep Grand cherokee

1998 Jeep Grand Cherokee) Build # 4135 Skp# 122921

Re: Engine Fan on 91 GV

Reply #11 –
If you roll underneath the coach with a creeper you should be able to get your eyes close enough to the fan blades to see if it's fiberglass. You can probably feel the fibers with your fingers. Also if you bend the blade a little bit you'll feel some give to the nylon fan but the fiberglass fan will be more rigid, because it's made of glass which is hard and brittle.
Scott Cook
1991 U300 36' 6V92TA
Old Town Penobscot 16
1984 Honda VF1100C (V65 Magna)

Re: Engine Fan on 91 GV

Reply #12 –
If I had to guess I would say it's already been replaced.  My fan was replaced when the coach was 10 years old and had 85k on it.  It showed wear and tare that I don't see in the photo of yours.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Engine Fan on 91 GV

Reply #13 –
The OE fiberglass fan on our rig looked pristine when I removed it. I bought a new black nylon plastic one from Foretravel after reading what happened to someone else here, and found the concept of getting stuck in the middle of nowhere with a destroyed cooling system... distateful. The OE fan has fibrous ridges you can feel and the new replacement is smooth.  I can't really tell whether your fan is OEM or updated from your pic though. if you want I'll take a shot of mine and post it here. Dunno if that'll help or not!
Jay
1989 U280 SE, 36', 3208T Cat, build 3292

Re: Engine Fan on 91 GV

Reply #14 –
Not much real info here.  IS the fan a 25- 26in with 6 bolts?