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| Diesel swap thoughts [message #311870] |
Fri, 06 January 2017 17:47  |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
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Just wanted to update my previous (November) remarks on the Diesel swap and maybe modify the conclusions I'd made a bit.
Over the last approximately 1900 miles it seems the combination has been 'dialed in' a bit more and the results have been pretty impressive. The mileage has definitely increased and the overall performance is better. A run from Albuquerque to Kingman AZ netted 15.95 mpg running into a head wind running 63/64 mph. On to Las Vegas and near 100 miles of Las Vegas urban driving, down to San Diego and over to Quartzsite managed 14+ (nice to carry 75 gallons and fill at the cheaper locations). The coach ran up Baker grade at 60 mph in 3rd gear. A direct comparison to the old motor 403/3.55 geared coach was 40 mph in second. If you aren't familiar with Baker grade it has been the death of many an RV. A six percent grade that peaks out about 4700' it's probably one of the 10 toughest hills in the west.
There still is a little tuning to be done but 15+ mpg and the performance of the combo really brings a smile to my old face. Ain't it fun.
Hal
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
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| Re: Diesel swap thoughts [message #311871 is a reply to message #311870] |
Fri, 06 January 2017 19:26  |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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If I had your skill set I'd do my 23' that way. Sigh. How's the split window coming along?
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Diesel swap thoughts [message #311876 is a reply to message #311871] |
Fri, 06 January 2017 21:11 |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
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Johnny Bridges wrote on Fri, 06 January 2017 18:26If I had your skill set I'd do my 23' that way. Sigh. How's the split window coming along?
--johnny
Not too well Johnny, seems others have much of my time allocated. Just finished a garage remodel at my daughters last week. Too bad they live 800 miles away but it does seem to give the GMC a work out. Their GMC is probably next up so the 63 will have to wait a while.
And I'm sure you could do your 23' just as well Johnny, but you really need an enclosed shop. 
Hal
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
[Updated on: Fri, 06 January 2017 21:13] Report message to a moderator |
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| Re: [GMCnet] Diesel swap thoughts [message #311877 is a reply to message #311876] |
Fri, 06 January 2017 21:21 |
Kingsley Coach
Messages: 2691
Registered: March 2009
Location: Nova Scotia Canada
Karma: -34
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Split window...63...we talking about a bus?
Sorry, couldn't help but overhear..
Mike in NS
On Fri, Jan 6, 2017 at 11:11 PM, Hal StClair
wrote:
> Johnny Bridges wrote on Fri, 06 January 2017 18:26
>> If I had your skill set I'd do my 23' that way. Sigh. How's the split
> window coming along?
>>
>>
>> --johnny
>
>
> Not too well Johnny, seems others have much of my time allocated. Just
> finished a garage remodel at my daughters last week. Too bad they live 800
> miles away but it does seem to give the GMC a work out. Their GMC is
> probably next up so the 63 will have to wait a while.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1974 Eagle Bus 45',w/slideout
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS
Life is too short to hold a grudge; slash some tires and call it even !
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| Re: [GMCnet] Diesel swap thoughts [message #311879 is a reply to message #311877] |
Fri, 06 January 2017 21:38 |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
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Kingsley Coach wrote on Fri, 06 January 2017 20:21Split window...63...we talking about a bus?
Sorry, couldn't help but overhear..
Mike in NS
1963 Split window Corvette, slightly modified 
Hal
On Fri, Jan 6, 2017 at 11:11 PM, Hal StClair
wrote:
> Johnny Bridges wrote on Fri, 06 January 2017 18:26
>> If I had your skill set I'd do my 23' that way. Sigh. How's the split
> window coming along?
>>
>>
>> --johnny
>
>
> Not too well Johnny, seems others have much of my time allocated. Just
> finished a garage remodel at my daughters last week. Too bad they live 800
> miles away but it does seem to give the GMC a work out. Their GMC is
> probably next up so the 63 will have to wait a while.
> Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1974 Eagle Bus 45',w/slideout
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS
Life is too short to hold a grudge; slash some tires and call it even !
_______________________________________________
GMCnet mailing list
Unsubscribe or Change List Options:
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"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
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| Re: [GMCnet] Diesel swap thoughts [message #311881 is a reply to message #311879] |
Sat, 07 January 2017 07:05 |
Kingsley Coach
Messages: 2691
Registered: March 2009
Location: Nova Scotia Canada
Karma: -34
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Senior Member |
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I wasn't even close! That's what I get for eavesdropping on conversations
Tks
Mike in NS
On Fri, Jan 6, 2017 at 11:38 PM, Hal StClair
wrote:
> Kingsley Coach wrote on Fri, 06 January 2017 20:21
>> Split window...63...we talking about a bus?
>> Sorry, couldn't help but overhear..
>>
>> Mike in NS
>>
>> 1963 Split window Corvette, slightly modified :lol:
>> Hal
>>
>> On Fri, Jan 6, 2017 at 11:11 PM, Hal StClair
>> wrote:
>>
>>> Johnny Bridges wrote on Fri, 06 January 2017 18:26
>>>> If I had your skill set I'd do my 23' that way. Sigh. How's the
> split
>>> window coming along?
>>>>
>>>>
>>>> --johnny
>>>
>>>
>>> Not too well Johnny, seems others have much of my time allocated. Just
>>> finished a garage remodel at my daughters last week. Too bad they
> live 800
>>> miles away but it does seem to give the GMC a work out. Their GMC is
>>> probably next up so the 63 will have to wait a while.
>>> Hal
>>> --
>>> 1977 Royale 101348,
>>>
>>> 1977 Royale 101586, Diesel powered,
>>>
>>> 1974 Eagle Bus 45',w/slideout
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>>
>>
>>
>>
>> --
>> Michael Beaton
>> 1977 Kingsley 26-11
>> 1977 Eleganza II 26-3
>> Antigonish, NS
>>
>> Life is too short to hold a grudge; slash some tires and call it even !
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1974 Eagle Bus 45',w/slideout
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Michael Beaton
1977 Kingsley 26-11
1977 Eleganza II 26-3
Antigonish, NS
Life is too short to hold a grudge; slash some tires and call it even !
_______________________________________________
GMCnet mailing list
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| Re: Diesel swap thoughts [message #311883 is a reply to message #311870] |
Sat, 07 January 2017 08:21 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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When I stopped of at Hal's place bringing the 26' back to Ga, he had/has a '63 Corvette in progress. Frame and driveline in one bay, body being reworked on a carrier in the other. You have to see Hal's work up close to appreciate his attention to detail, fit, and finish. Get a tour nect time you're at the same rally.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Diesel swap thoughts [message #311887 is a reply to message #311883] |
Sat, 07 January 2017 10:57 |
Hal StClair
Messages: 971
Registered: March 2013
Location: Rio Rancho NM
Karma: -12
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Thank you for the kind words Johnny  Hoping to get the time to finish up some projects, the SW is high on the list for sure. Wonder how I ever got things done before retirement. Hal
"I enjoy talking to you. Your mind appeals to me. It resembles my own mind, except you happen to be insane."
1977 Royale 101348,
1977 Royale 101586, Diesel powered,
1974 Eagle Bus 45',w/slideout,
Rio Rancho, NM
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| Re: Diesel swap thoughts [message #311888 is a reply to message #311870] |
Sat, 07 January 2017 12:04 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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I wish my shop would accommodate the GMC. It has to live outside on a pad.. which precludes work today. On a fixed income though, there isn't one in sight.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Diesel swap thoughts [message #311889 is a reply to message #311883] |
Sat, 07 January 2017 12:48 |
kerry pinkerton
Messages: 2565
Registered: July 2012
Location: Harvest, Al
Karma: 15
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Johnny Bridges wrote on Sat, 07 January 2017 08:21...You have to see Hal's work up close to appreciate his attention to detail, fit, and finish. Get a tour nect time you're at the same rally.
--johnny
I'll agree. There are few people who can match the skill, engineering, and quality of Hal's build. Absolutely first rate work. I consider myself a pretty good fabricator but Hal is WAAAY above my skill level.
Kerry Pinkerton - North Alabama
Had 5 over the years. Currently have a '06 Fleetwood Discovery 39L
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| Re: Diesel swap thoughts [message #312022 is a reply to message #311870] |
Wed, 11 January 2017 10:23 |
xplorid
Messages: 213
Registered: February 2012
Location: Boise
Karma: 0
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For those of us with more $$ than fabrication skills, Manny sells a diesel conversion kit that mates to the TH425. I was Kit #9. Drove the 455 from Boise to SanJose, over the Owyhees and Sierra Nevadas. Got a bit over 8mpg. Manny with my help took a week to drop the 455 install the 6.5TD from AM General and button up. Drove back with a new diesel and got 12.5mpg. Not sure if I will see the kind of mileage Hal has seen, but he has an OD transmission, and it is really not about the mileage anyway. It's about having adequate torque where it is needed, and eliminating all that engine worry - overheating, vapor lock, carb adjustments, etc etc. All gone. More of a mule than a race horse, but so far it seems like the engine belongs in this vehicle.
Looking forward to logging some miles this year, as soon as we are released from the grip of the worst winter here in 30 years.
Sure would like to get the spare 403 into somebody's vehicle, instead of my garage.
Jeff
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back
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| Re: Diesel swap thoughts [message #312034 is a reply to message #311870] |
Wed, 11 January 2017 13:04 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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Roughly what cost, Jeff?
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Diesel swap thoughts [message #312035 is a reply to message #311870] |
Wed, 11 January 2017 13:49 |
xplorid
Messages: 213
Registered: February 2012
Location: Boise
Karma: 0
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Please ask Manny, don't quote me, but I remember the kit price around $11K. , and . I did lots of other repairs and upgrades while at the shop, including the 52 gal fuel tank and a trans rebuild, so my bill out the door was closer to $15K. I recall some reference to the diesel in my kit being the last one of the first batch so engine prices may have changed. The interest in the conversions was quite high until gas prices dropped, and will be again when they go up. Really with the differential in gasoline-diesel the fuel savings are not a rationale for spending the money on a conversion. In my case the 455 was worn out anyway, and wanted to end up with a 20 year solution.
Jeff
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back
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| Re: Diesel swap thoughts [message #312036 is a reply to message #311870] |
Wed, 11 January 2017 14:37 |
jhbridges
Messages: 8412
Registered: May 2011
Location: Braselton ga
Karma: -74
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Senior Member |
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Makes sense with a tired motor. ~~ two 455s, and it ought to outlast two of them. You pays your money and you takes your choice.
--johnny
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
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| Re: Diesel swap thoughts [message #312046 is a reply to message #312035] |
Thu, 12 January 2017 08:23 |
Russell K.
Messages: 178
Registered: October 2016
Location: Dunedin, Florida
Karma: 4
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Jeff,
Did you also change to a diesel generator? If so, which one? an Onan? How much? If not, do you have one fuel tank for gas and another for diesel?
Thanks for the info.
Russell
1978 Eleganza II, Dunedin, Florida
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| Re: [GMCnet] Diesel swap thoughts [message #312048 is a reply to message #312047] |
Thu, 12 January 2017 09:32 |
xplorid
Messages: 213
Registered: February 2012
Location: Boise
Karma: 0
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Propane. Did the conversion by myself, it was easy after I figured out a plumbing scheme. My GMCII has an Onan 7000 from 1994, it ran well enough before, even better on propane. If it ever craps out I would shop for diesel replacements, but they are really expensive and I am told noisier and shakier in our little coaches.
1974/94 GMCII by Explorer
Manny 6.5 TD Al radiator
1 ton front 4 bags back
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| Re: [GMCnet] Diesel swap thoughts [message #312050 is a reply to message #312048] |
Thu, 12 January 2017 10:19 |
bdub
Messages: 1578
Registered: February 2004
Location: Central Texas
Karma: 5
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Oh, you need to see Hal StClair's diesel generator installation. Another
work of art!
And, quite as a mouse!
bdub
On Thu, Jan 12, 2017 at 9:32 AM, jeff sugheir
wrote:
> Propane. Did the conversion by myself, it was easy after I figured out a
> plumbing scheme. My GMCII has an Onan 7000 from 1994, it ran well enough
> before, even better on propane. If it ever craps out I would shop for
> diesel replacements, but they are really expensive and I am told noisier and
> shakier in our little coaches.
> --
> 1973/94 GMCII Manny 6.5 TD AL radiator 1 ton front 4 bags back, Huber TBs
>
>
>
> _______________________________________________
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bdub
'76 Palm Beach/Central Texas
www.bdub.net
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