Author Topic: Starting an 8v71  (Read 3912 times)

Offline RL

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Starting an 8v71
« on: August 02, 2013, 07:45:02 AM »
In about 6 weeks I'll be back in Anza, Ca (southern California) to start the bus I bought sight unseen which I had my first look at in early July. And I liked what I saw. But it's been sitting for 3 years with its fuel tank half full. That's a lot of diesel to drain and transport 30 miles to a recycle site. So was searching for ideas and ran into a 2009 post by TomC which said:

"Personally- I would check the oil level, pull one of the fuel filters to make sure fuel is in it, and try starting it!  Diesels are not like gasoline engines-even when the fuel gets a bit stale, a Diesel will still run.  I suggest you run the engine first, make sure the fuel is flowing well before changing the fuel filters.  You can loose the fuel prime when changing the fuel filters-which makes for a very hard restart of an engine.  Put in fresh batteries, start the bus from the rear, and before cranking, hold the stop lever on the governor in the stop position with your finger, crank the engine with the lever in no fuel position, and after 5 seconds of cranking, slowly release the stop lever, and the engine should start.  This is also a good trick to do when it is very cold, since it retards the timing and will many times get a hard starting cold engine started easily.  Good Luck, TomC"

So my question is should I add fresh diesel to the tank to improve the overall fuel quality before starting it for the first time? Or does anyone have a alternative suggestion?
1962 PD4106-1546, 8V71, Allison V-730
Birch Bay, Washington

Offline bevans6

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Re: Starting an 8v71
« Reply #1 on: August 02, 2013, 08:00:50 AM »
diesel doesn't really go bad like gasoline does.  I have run my bus on two year old fuel and really didn't even think twice about it.  The filters will catch any algae and clog, so don't go driving any long distances till you prove that won't happen.  I'd crank it with the engine stop lever moved to the stop position for 20 - 30 seconds, then let the stop lever go to run and see what happens, just like Tom wrote.  Before I did that, I would check that the injectors are all free and move with the rack, and that both racks to go to no-fuel.  You may not even have to prime it.  I wouldn't add anything to the tank at all.

1980 MCI MC-5C, 8V-71T from a M-110 self propelled howitzer
Allison MT-647
Tatamagouche, Nova Scotia

Offline RJ

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Re: Starting an 8v71
« Reply #2 on: August 02, 2013, 08:05:23 AM »
RL -

Sitting for 3 years in S CA is a lot different than sitting for the same period in WA.  With the much lower humidity, there won't be as much water condensation in the fuel tank.

So my recommendation is to pick up a bottle of Bio-Bor to break up any algae in the tank, pick up extra primary and secondary fuel filters (2-3 each), and a five-gallon diesel fuel can.  If the coach starts right away, then say good-bye to the seller and head to the nearest diesel fuel station ( to top off the tank, add the correct dosage of Bio-Bor, and point your coach homeward bound.

(If you take Hiway 99 thru Central CA, I'm in Fresno, and extremely familiar with the 4106s.  Give me a call, and I'll be glad to meet with you and help you get acquainted with your new toy.  Contact info is in my profile, just click on my name to the left.)

Don Fairchild, a Detroit Diesel guru, is in Bakersfield, on your way home, btw.  Also, Ted Campbell, at Coach Maintenance in Williams, CA (45 min N of Sacratomato) knows these buses inside-out and upside-down.

FWIW & HTH. . .

RJ Long
PD4106-2784: Donated to the Pacific Bus Museum
S14947: 1980 MC-5C Shell 6V92/HT-740
S13406: 1978 MC-5C Angola Coach - Swapped for vvv
M1001907: 1992 Prevost XL Vantarè Conversion 8V92T/HT-755 (DDEC/ATEC)
Cheney WA

Offline bobofthenorth

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Re: Starting an 8v71
« Reply #3 on: August 02, 2013, 08:09:38 AM »
Others have already said what I would have.  Definitely no need to dump the fuel.  In the marine world diesel fuel sits for multi-years before it gets burned.  In the ag world fuel routinely sits for 10 months.  I have no experience with the "algae" that grows in fuel in warmer climates but you've already got some advice regarding that.  It seems to me that in the worst case you could drain the tank and then pour the diesel back into the tank after straining it through a coffee filter.  Its not rocket surgery.
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Offline Emcemv

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Re: Starting an 8v71
« Reply #4 on: August 02, 2013, 09:27:59 AM »
Mine sat for 2 years in CT before I got it, changed the filters and started it. Drove it to get fuel. Been fine ever since.
Bruce & Nancy Fagley
1973 MCI MC-7 Combo Freighter
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Offline Boomer

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Re: Starting an 8v71
« Reply #5 on: August 02, 2013, 09:45:55 AM »
The fuel in my Silverside sat for almost 30 YEARS.  It started right up and I burned it ALL.  It sat all that time in the desert though, not in a humid environment.  Filtration is the key, as mentioned above.
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Offline luvrbus

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Re: Starting an 8v71
« Reply #6 on: August 02, 2013, 09:59:07 AM »
If it has 100% fuel it is never a problem the Bio blend fuel will go to hell in a hurry here in the AZ heat
Life is short drink the good wine first

Offline Dave5Cs

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Re: Starting an 8v71
« Reply #7 on: August 02, 2013, 11:40:29 AM »
Having had large ponds all my Adult life Algae needs sunlight to grow anywhere, unless you have holes in your tank it ain't Real Algae.

Note:Taken from 'The Diesel Doctor" website

 "What is diesel fuel "algae"?

Algae are a life form found in water, similar to algae growing in an aquarium. Algae do not live in fuel and it requires sunlight to grow. For years, people have been referring to tank sludge and the jelly, slime and other contaminants found in fuel filters as “algae”. The colloquialism “diesel fuel algae” is widely used and understood. However, there is no relationship between the “algae” growing in your aquarium and the sludge “growing” (forming) in your fuel tank and showing up on your filter elements.

There are three basic areas of concern about contaminants in fuel and oil:

1. Water

2. Inorganic debris (sand, dust, rust, etc.)

3. Organic debris (fuel breakdown products and waste products of fuel deterioration and re-polymerization)

The organic debris represents more than 90% of all contaminants found in fuels and oil. It is this organic debris, the sludgy, slimy, acidic material that people refer to as “diesel fuel algae”. It could also be called a polymer, tar, wax or asphalt!"

Just saying!...

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Offline Chopper Scott

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Re: Starting an 8v71
« Reply #8 on: August 02, 2013, 05:56:30 PM »
As with any forum question you get many responses. Put batteries in the ole girl and hit the switch!! You'll know soon enough.
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Offline chessie4905

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Re: Starting an 8v71
« Reply #9 on: August 04, 2013, 08:03:48 AM »
   Before cranking over,I'd consider slightly loosening the oil drain plug to check for presence of coolant/water. It'll drip out first, as oil floats on water.
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Offline John Z

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Re: Starting an 8v71
« Reply #10 on: August 14, 2013, 07:26:46 AM »
May as well drain a little fuel too to be sure there if no water in there.
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