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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: roadrunnertex on July 11, 2008, 04:47:17 PM

Title: V730 transmission PTO question.
Post by: roadrunnertex on July 11, 2008, 04:47:17 PM
The V730 has a optional PTO output drive that is used on some coach models to operate a A/C Compressor and a alternator if my memory serves me right. ???
The question I have does this PTO shaft turn the same rpm speed as the 8V/71?
Also does any one drive a 12volt single wire alternator to charge up the house batterys on there 24 volt coach?
The reason I am asking all of these questions the V730 in my GMC has a block off plate and before I buy a PTO drive shaft and try to install the PTO shaft is it worth the effort and time to do so.
Has any one have a PTO shaft that they are not using would it be for sale. :o
Thanks
jlv :P
Title: Re: V730 transmission PTO question.
Post by: Barn Owl on July 11, 2008, 05:20:44 PM
Good question, I have wondered the same. There was a 4905 "Woody" in BCM some issues back that used the PTO to run an auto a/c compressor. I wonder if Nick at Nimco would have them.
Title: Re: V730 transmission PTO question.
Post by: Hartley on July 11, 2008, 05:53:45 PM
The "PTO" shaft on the V-730 series transmission is driven off a special 3 gear cluster that is installed at the same time as the PTO system. You cannot simply insert a shaft to make it work. The transmission has to have the option already installed which would mean if one is built without a PTO cannot generally be added by inserting a shaft.

In a word about engine speed at the PTO, NO it is a gear driven through 3 gears that reverse the rotation (twice?). I don't have the V-730 book handy but it is different.

The PTO shafts were used to operate the A/C compressor and an auxillary 12 volt alternator ( on Flxible 870 Buses ) and without the auxillary alternator on the RTS buses and others.

You may need to talk to one of the guys that have added an extra take-off pully to the camshaft pulley if you have room. Or find someone familiar with adding a secondary output shaft and pulley on the back of the engine at one of the spare accessory ports. ( takes parts to do that! )

Hope that helped...

Dave..
Title: Re: V730 transmission PTO question.
Post by: RTS/Daytona on July 11, 2008, 07:10:27 PM
Power takeoff (Optional)
Type....................................Engine-driven shaft type
Location..Right side of vehicle, parallel with engine centerline
Drive gear ratio.............................1.48 x engine speed
Drive gear rating........................50 hp (37kW) continuous

source--> http://www.industrialautomatic.com/html/vspecs.htm
Title: Re: V730 transmission PTO question.
Post by: TomC on July 11, 2008, 07:23:55 PM
What's involved to install the PTO is to remove the transmission from the bus (translated the engine cradle) and install the gear set and re install the transmission and engine cradle.  Not worth the money unless you are already going to overhaul the transmission.  Good Luck, TomC
Title: Re: V730 transmission PTO question.
Post by: chris4905 on July 11, 2008, 09:43:38 PM
Hi John,

As you may remember, last year I did an engine replacement, the 6V92 into my 4905, and I also did the V730 upgrade.  My V730 came from Nimco with the aux shaft installed.  I have removed it, as I don't plan on using it (put the cover plate on it), and unfortunately I have already gotten rid of it.

I installed a one wire 12V alternator on the side of the 8V71 when that engine was still in the bus.  It worked well for years and was still working when I removed it from the 8V when I did the 6V install.

I can send you pictures of the alternator install on the 8V71, if you want.
Title: Re: V730 transmission PTO question.
Post by: Barn Owl on July 12, 2008, 04:37:45 AM
What about using the PTO that operated the OTR A/C on the GMs?
Title: Re: V730 transmission PTO question.
Post by: roadrunnertex on July 12, 2008, 07:30:42 AM
Lot of good information also it's good to hear of a different approach to driving the alternator from the old A/C drive.
This is one way solve the problem.
Thanks so much for the good tips. ;D
jlv :P
Title: Re: V730 transmission PTO question.
Post by: kingfa39 on July 12, 2008, 09:35:00 AM
John, i use the pto shaft from the 8/71 that drove the original a/c to drive my in dash a/c, i have a double pulley so i could drive a alternator as well if i needed it, id work with that, if you need more info email me and i sure will help anyway i can .
Frank allen
Title: Re: V730 transmission PTO question.
Post by: kingfa39 on July 12, 2008, 09:41:33 AM
John, maybe this http://users.myexcel.com/roncarter/splitSystem will help,
Frank allen
Title: Re: V730 transmission PTO question.
Post by: Sojourner on July 12, 2008, 05:44:25 PM
FWIW
Learned from Frank's link, the supplier of A/C blower housing and etc link:
http://www.rainbowproductsonline.com/mm5/merchant.mvc?Screen=CTGY&Store_Code=EMP3140&Category_Code=1

Thank you Frank!

FWIW

Sojourn for Christ, Jerry
Title: Re: V730 transmission PTO question.
Post by: kingfa39 on July 14, 2008, 09:50:00 AM
sojourner, you are more than welcome, ive had this system for a number of years, hope you can get some good out of the info, has worked well for me
Frank allen
Title: Re: V730 transmission PTO question.
Post by: chris4905 on July 14, 2008, 09:38:53 PM
John,

Here's a picture of the GM 1 wire, 50A, alternator I put on our 4905.  It worked great (for about 6 years) and was still working when I took it off to do the engine change.  As you can see it ran off the pulley on the front of the engine by the fan.  Just fabricated a few brackets, put a circuit breaker right off the alt., and ran the "1 wire" to the 12V batts up front.

Chris
Title: Re: V730 transmission PTO question.
Post by: roadrunnertex on July 15, 2008, 07:52:50 AM
Thanks so much for the update and photo. ;D
The jury is still out so to speak on which way to go with this project.
Did you get you engine swap project finished?
jlv :P
Title: Re: V730 transmission PTO question.
Post by: tekebird on July 15, 2008, 09:07:34 AM
both of my MCi's have 12v alternators to power a number of 12 v items.

I would not screw with the PTO, but would rather set up your alt like the Retrofit a/c compressor system on the late model 08's and 05's

Title: Re: V730 transmission PTO question.
Post by: bigjohnkub on July 16, 2008, 08:41:17 AM
John, my 4903 has an altenator mounted under road air. I wondered what it was for since their is no wiring and it is not in the book. Big john
Title: Re: V730 transmission PTO question.
Post by: roadrunnertex on July 16, 2008, 09:29:27 AM
OK,it's a 48 volt alternator and it was used to provide power for the A/C condenser fan. ::)
The later mpdel GMC Buffalo's used a 24 volt condenser fan motor so the extra alternator was not needed.  ;D
jlv ;D
Title: Re: V730 transmission PTO question.
Post by: Barn Owl on July 16, 2008, 03:09:42 PM
I know the 4106s used hydraulic motors to operate the condenser fan.
Title: Re: V730 transmission PTO question.
Post by: johnjem on July 17, 2008, 06:03:25 PM
u can have mine u just need to remove it  john    e-mail me if u want it    johnjem@comcast.net