Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Protech Racing on April 02, 2017, 07:24:28 pm

Title: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 02, 2017, 07:24:28 pm
 I have looked around most of these forums and cant seem to find the old Chasssi info. 1988  GV  Oshkosh 917.
  Questions; Does it have air  disc brakes?
  How many airbags? 
 Is the Cat 3208 Turbo?
 Is there a spec sheet some place?
 I put in a bid and won this nice looking unit. I would like some info before I  make the trip to fetch it the 300miles home.
 Thanks for any and all info help.
 Mike Ogren , FL.
Title: Re: Oshkosh 917 Chassis data?
Post by: red tractor on April 02, 2017, 07:47:40 pm
It has 4 air bags and does not have air disc brakes, but has air drum brakes and it has a 3208 turbo cat if with rear radiator is 250 horse, if with the side radiator is 300 horse. I have worked on many of these so if you have any questions call me or send a pm I live near Tampa, FL. Phone 813-215-3463 Ron
Title: Re: Oshkosh 917 Chassis data?
Post by: fouroureye on April 02, 2017, 08:43:07 pm
Owned.. for 9 yesrs.. 90k miles, all good PM me I'll give you my phone #
Title: Re: Oshkosh 917 Chassis data?
Post by: Old phart phred on April 02, 2017, 09:23:49 pm
Check tire dates 7 year old tires on the front and you may want to drive it to the nearest tire shop first.
Title: Re: Oshkosh 917 Chassis data?
Post by: Olde English on April 02, 2017, 11:26:54 pm
     We have the same coach as you bought or at least close to. Lots of info' available on the beamalarm web site and searches on the forum will yield more.

  Shoot me a PM and I'll help as best I can !

Happy Trails  ^.^d 
Title: Re: Oshkosh 917 Chassis data?
Post by: danieljeff545 on April 03, 2017, 08:03:02 am
You'll find great info here for it. Great coach, we just ran 26 hours straight to south Florida from Michigan Friday night. Smooth as glass.  Good luck with her!
Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 03, 2017, 08:09:29 am
Thanks so much.  I looked hard for any negative feedback on these coaches  but found only Love.

The sales people checked the tires. All sub 4yrs old.  "It runs ,drives and stops".. So I made a bid .
  Are there any manuals on this site?  Thanks,MM
Title: Re: Oshkosh 917 Chassis data?
Post by: Texas Guy on April 03, 2017, 06:27:02 pm
If you find a set of manuals please PM me. I am trying to bring one back to life.

There are several of us that have the old Oshkosh chassis on here. They are fun

to work on and with the help of the people at Old Town Motorhomes here in

Nacogdoches it has been an adventure. They are so simple, everything mechanical.

Mine has a spring suspension, which is not quite as comfortable as one with air ride,

but, again low maintenance. Mine was low milage, one owner and fairly well maintained.

My other FT is smoother but not the coach this one will be, I hope. Good luck with yours.

Carter-
Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 09, 2017, 08:31:46 pm
 Update. The bus made it the 300 miles home last night .
 It has 3 full manuals .
  Lots of little notes.
 Full air ride,  air drums, Turbo Cat, ally,  Propane Onan 5K gen that runs nice, one roof air works well .
 Ran better as we went ,stopped worse as we went .  10MPG ? 200miles and topped of the tank  with 19.8 gal . The full pump needs at least one turn ?  No  real off idle power.
 1) The speedo reads 7MPH fast . 2400RPM is 62 real MPH , reads 70.   
 Maybe it has had a axle swap? The only road noise is rear gear hum. Not narly , just a whine at under 60.
 Cruise works well !!
 2) The brakes  are very weak . the low pressure light and buzzer come on at any hard stop.
 3) The trans and engine dont like part throttle . Flat down it spools up only in third and pulls best in top gear . I hope that a small fuel pump turn will add some power . It has no smoke at all .
 I suspect an air pressure leak  that affects the air controls, throttle , brakes ?
Title: Re: Oshkosh 917 Chassis data?
Post by: craneman on April 09, 2017, 08:53:04 pm
You have a major leak going out of the treadle valve when you apply brakes. That is why braking is weak. Have someone step on the brake pedal while you listen outside you will find it.
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 09, 2017, 09:51:21 pm
All Oshkosh v917 chassis have a brass lq4 valve in the dash.  The front brakes do not work until the application pressure exceeds 60 psi.

The nature of the wedge brakes with its full backing plate is that in reverse they squeal loudly. 

So Foretravel had Oshkosh put in the disabling valve that was made normally for the front axle brakes on a truck tractor.

No loss of steering control in snow, ice conditions.

I had truck fleet owners change the brake cans on the wheels and change the "pill" in the treadle valve(brake pedal) for less pedal pressure needed and stronger brake shoe pressure at the drum.

Easy to show this with a few stops and then walk around the coach and check the rims temp.

If you plumb around the valve to connect the front brakes at all pressures the loud noise in reverse should be expected.

Removing the drums and deglazing the shoes and drums themselves helps.  Most old guy owners babied the coach.

Engines not broken in and glazed brakes are normal.

That's why I took almost every used coach rv'ing when I ran the store.

Stretching the throttle cable and hard apllication of the brakes helped things out.

Does your rear axle hum  come on under power? 

Gen is 6.5.  One gph almost regardless of load.  58 gallon actual capacity(300 pounds @ 80%)

Part fuel,  you will feel the fuel slosh fore and aft as the coach stops.  Tank is fore and aft

Sold a lot of these

The rear noise is fixable
Title: Re: Oshkosh 917 Chassis data?
Post by: Old phart phred on April 09, 2017, 11:51:16 pm
So is the 917 chassis a 4 air bag suspension with a trailing arm front and rear sprung by an air bag on each side, or is the front a leaf spring and only the rear riding on 4 air bags?
Title: Re: Oshkosh 917 Chassis data?
Post by: Texas Guy on April 09, 2017, 11:52:55 pm
Glad you got it home. Mine was sluggish at first and got better by the mile. I used some

Sea Foam fuel treatment before I pulled out, seemed to help. The big help was changing

fuel filters. The trans. will shift much better after a fluid and filter change, synthetic. The cruise

control is a big plus. The rear whine may be as much tires as differential. First thing is to find

the air leak and get that stopped. Glad the air did not get low enough for the emergency to stop

you dead in the road. Check your air bags and see if they are leaking. Think you are going to like

the Cat engine. It is not a 450 horse Cummins but it will get you there and back. Mine has a lever

to the left of the steering column, like a clutch. I thought it was a retarder but Bob told me that those

coaches did not have retarders, with out manuals I'm going to have to find an older mechanic to tell

me what it is? You have many hours of work ahead of you but you will have something to show for

your efforts.

Good luck,

Carter-
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 10, 2017, 12:10:18 am


The small lever is to  tilt the Donaldson steering column. 

The telescope part is the outside horn ring. 
Title: Re: Oshkosh 917 Chassis data?
Post by: Texas Guy on April 10, 2017, 12:21:26 am
Bob,

This is a large foot pedal. I will try to post a pic, next week.

Carter-
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 10, 2017, 12:26:10 am
917 is a four airbag total setup. Trailing beam front.  15x4 front wedge cam brakes.  15x7 rears.

Some bump steer from suspension travel.  Don't oversteer it in dips.

Will go one way entering dips and coming out of them go back the other way.  Then back to straight.

Check for ride height valve consistency.

Measure coach heights all around at idle.  Drop air suspension.  Reinflate.  Check heights again. Do it one more time.

If the coach comes back to the same height every time it will go straight better.

Spicer 710 steering box spool needs centering if the coach sometimes heads for the roads edge.

It's in the manual from Oshkosh if you have the books.

Three hour shop time and remove the steering box and put it on the bench stuff.

Then these can drive from the bottom of the steering wheel
Title: Re: Oshkosh 917 Chassis data?
Post by: craneman on April 10, 2017, 01:01:54 am
Any chance you have a Jake brake? My Monaco used a pedal left of the steering wheel to engage it instead of the auto function.
Title: Re: Oshkosh 917 Chassis data?
Post by: Texas Guy on April 10, 2017, 10:43:16 am
Thanks C-Man,

    I will check that out. The coach has a 3208T in it. Would be more than

happy for a set of Jakes on it.

Carter-
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 10, 2017, 11:56:13 am
The v8 block is not the high torque design like the inline 6's that replaced them.

In reverse the exhaust brakes do not have the same effect on retardation as the sixes.

Jake would require lots of parts with two heads.

Eddy current rear axle retraders worked well up to their temp  limits.

Vogue had them on their crown chassis with their 6v92's.

They also had zf six speed trans before the world class allisons were released

Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 10, 2017, 10:06:45 pm
 Found a large part of the no brakes;  The LF brake can/rod and lever( slack adjuster)  are not connected to the S cam shaft. The clip is gone and the rod pushes on nothing.  Looks like easy fix.  Did an air pressure drop test and no leaks .

 Does the 2500RPM @ 65MPH sound high?  TIA, MM
Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 18, 2017, 10:29:50 pm
The front brakes  are cam driven, the rear brakes are wedge style.  The book shows wedge style both ends. I guess that the front end/axle  has been replaced . No crash damage apparent .
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 18, 2017, 10:35:28 pm
Yes they were all wedge.  Full backing plates.

Yes on the speed/rpm. 

Full revs governed at 2650 for a 250 cat.

Speedos wrong?  Verify with gps driving?

Should have 9r22.5 tires. 

255?
Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 19, 2017, 09:03:13 am
GPS says 62, speedo says 69-70.

  new 255/70 / tires.  Sampson.
 Thanks,MM
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 19, 2017, 02:12:37 pm
I do not think that the v917 had 70 series tires.  80? 

Found a post where someone was replacing the 9r's

The tire that matched up best to my 9R22.5 was the 265/75R22.5 and I had a choice of 4 manufacturers - Michelin, Goodyear, Toyo, and Bridgestone. I picked the Toyo. Every measure the same except for 1" width increase.

255/70's would seem to be shorter?

The 300 ored side radiators came with 10r's btw
Title: Re: Oshkosh 917 Chassis data?
Post by: wolfe10 on April 19, 2017, 03:35:22 pm
Yup, two alternatives to the 9R: Michelin 255/80R22.5. Other brand's 265/75R22.5.
Title: Re: Oshkosh 917 Chassis data?
Post by: Mike Leary (RIP) on April 19, 2017, 03:41:22 pm
Yup, two alternatives to the 9R: Michelin 255/80R22.5.

A great tire for down here, wider, but plenty of clearance. Rides perfect at 82 psi!
Title: Re: Oshkosh 917 Chassis data?
Post by: red tractor on April 19, 2017, 09:56:10 pm
If you have the s cam front brakes, then you must have the 300 hp cat with the side radiator.
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 20, 2017, 01:56:37 am
Red tractor:  I do not remember that the 300 had different front brakes from the 250.  You sure?
Title: Re: Oshkosh 917 Chassis data?
Post by: Bill Willett on April 20, 2017, 10:11:21 am
Red Tractor is one of the better mechanic's and I trust his judgement, he is not a sales person.
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 20, 2017, 12:29:23 pm
Bill I sold these new and was a product guy and had the chassis blueprints from Oshkosh and was not aware of a brake difference between the ORED 250 and the 300 ATAAC. 

They all had the lq4 front brake disconnect below 60 psi apllication pressure as far as I tested.

My info stopped the first time in late 89.

Went back in 93.

Simply idle curiosity and to add to my weird product knowledge.

More brakes would have been a good idea as I could get smoke from the rear drums down long grades at medium brake pedal pressure as the fronts were not connected.

Front rims cold to the touch.  Rears hot.

Tested many times.

Bigger s cam front brakes and having them on at all pedal pressures would have helped this I think.

Marquis had much larger s cam brakes with no backing plates and used to shudder in reverse some
Title: Re: Oshkosh 917 Chassis data?
Post by: Protech Racing on April 20, 2017, 12:50:49 pm
This one  is #31273,  11/ 87, 9r tires. Rear rad- no charge cooler. 
  It shows some slight "run over  object" damage . The fuel tank bracket has a center hit, the trans pan has a dent.    I am guesing that the axle was swapped.
 Thanks for the tips ,MM
 Edit ; found the Oshkosh delivery tag;  S cam front , wedge rear brakes. 
Title: Re: Oshkosh 917 Chassis data?
Post by: red tractor on April 20, 2017, 05:49:42 pm
Maybe remembering wrong, but thought so, of course that was a lot of years ago and much water under the bridge since then.
Title: Re: Oshkosh 917 Chassis data?
Post by: Caflashbob on April 20, 2017, 06:14:41 pm
No!  Really red?  Haha