Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 13, 2025 ...

Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #25 – August 12, 2022, 05:08:17 pm

Nitehawk you are the man! Josh has fan coming  to me he feels like work so thank all of you guys for your help and input! We should be back on the road in a couple of weeks!!  Dennis

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #26 – August 17, 2022, 08:49:10 am

Dennis, has the fan showed up yet??

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #27 – August 18, 2022, 10:31:27 pm

Yes sir I received it yesterday!  It looks good and is a direct replacement.  It is a 7 blade versus a 6 blade but has the same pitch so it will provide a little additional cooling that will not hurt a thing!!! I little FYI to all you owners with a fiberglass blade change it!!!  Thank you again Nitehawk!!  The radiator will take 2 more weeks to get here it had to be made being it was a 6 row!  I'm not looking forward to the reassembling it's  a pretty thought job!

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #28 – August 20, 2022, 07:07:47 pm

Ok  guys what pressure radiator cap should I us?  Apparently I placed mine in the wrong place and it got mashed.
6V92 Detroit 1991 Grand Ville rear radiator!

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #29 – August 20, 2022, 10:12:29 pm

Does it have a coolant recovery bottle ?    I use 9# with a bottle .

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #30 – August 28, 2022, 10:14:45 pm

Mike , it does have a bottle so is that a 9psi cap?

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #31 – August 28, 2022, 10:52:56 pm

The Detroit factory has 7 psi for their replacement cap. Replacement caps are available from 7 to 16 psi. After reading the Wanderlodge forum and from my experience with ours, I think that after fitting the rear and rear side radiators to many of the Foretravel models, some have experienced marginal cooling in some environments such as summer, long grades and high altitudes. Ours is no exception as it's really a three season coach for not really having to monitor the temp gauge that closely.

At 7 psi, a 50/50 mix will boil at 248 F. With a 15 psi, the same mix will boil at 265 F. Naturally, interior cylinder passages may be quite a bit higher than where the sensor is located. If the coolant does boil, it creates a partial void and less cooling occurs around locations like the exhaust valve.

I checked our OEM cap and it has the 15 psi stamp on it. Not likely that either the PO or anyone else replaced it. I think that when Foretravel installed the rear radiator in the U300, they derated the Detroit to 300 hp with a firmware change as the available Allison would not handle the torque of the 350 hp engine. So, when they went to the side radiator and 746 Allison, they updated the ECU to 350 hp in 1992 and installed the vertical single fan radiator. This was not enough and many overheated so the next year, they went to a larger horizontal radiator with two hydraulic fans. The problem is the second fan uses even more power to run and power is heat. I think this is why the 15 psi cap was OEM on ours. A stopgap measure for a poor cooling design.

In marine use, the 6V-92TA gets all the cooling it needs from the ocean or river so up to 620 hp can be squeezed from the engine with only a change to the ECU.

Even U225 members have had cooling problems with some adding an aux front radiator to better cool their engine.

Pierce

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #32 – August 28, 2022, 11:13:21 pm

Yes. I use a 9 with the bottle. It sounds important to keep the rad full .

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #33 – September 05, 2022, 08:50:10 pm

The coach is ready for the road again, new 7 blade fan and new radiator installed .  If anyone has a fiberglass fan I strongly recommend changing it!  I've driven it on a short trip all is fine. Thank all you guys for you input as the fan was a problem to find and don't rely on Foretravel for any help.
Dennis

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Re: Cooling fan 6V92 Detroit rear radiator fiberglass fan

Reply #34 – November 24, 2023, 06:37:06 pm

Do you have a part number for the replacement fan?

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