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Author Topic: 8V71 oil leaks....why?  (Read 4228 times)
tomhamrick
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« Reply #15 on: May 23, 2009, 04:45:13 AM »

I have a 6V92TA in my Eagle that I have run for 11 years without any major leaks. I had a small one when I bought it an found it was a loose hose clamps on a crossover pipe between the heads. No more leaks!!! This is not an urban legend as it has been verified at the Southeast Busnuts Rallys.  Grin My engine was supposed to have 500 miles on a Reliabilt rebuild when I bought it so I guess that's why no leaks. So far so good!!
Tom Hamrick
1984 Eagle 10S
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Tom Hamrick
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kingfa39
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« Reply #16 on: May 31, 2009, 05:59:45 PM »

a older dd mech showed me yrs ago that a 2 stroke does not have to leak, he said its the way they are put together, and he was right because i seen it.
Frank Allen
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JohnEd
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« Reply #17 on: May 31, 2009, 10:49:13 PM »

Frank,

I seen it too.  BUT i hear so many times that ALL DD 2 strokes leak.  So many jokes about it.  From what you and TomC have said(and others) it is a matter of proper use of gaskets and sealants and torque.  Sound fair?  Must be a lotta hacks out there passing themselves off as mechs.

Thanks for the answer,

John, the ever wiser but never quite smart.
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The price of apathy towards public affairs is to be ruled by evil men." Plato
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Dreamscape
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1968 Silver Eagle Model 01 8V71 Allison 740 #7443


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« Reply #18 on: June 01, 2009, 05:30:23 AM »

Our 871 is bleeding too! Not sure where it's coming from, I suspect from around the blower. I need to pull all the crap from under the bed and dive into it. Any ideas on what to look for? I have manuals for the engine, those suckers weigh about 20#!  Roll Eyes

At least the oil is keeping down the dust!  Grin

~Paul~
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luvrbus
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« Reply #19 on: June 01, 2009, 05:55:11 AM »

Paul, there is a 1/4 inch oil line for the blower on the rear that has a compression seal on the blower end that goes bad over time cost .78 cents and most of the time you will find that is were your leak is      good luck
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RickB
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« Reply #20 on: June 01, 2009, 06:14:00 AM »

If you're dripping at idle check the airbox spitter check valve tubes on either side of the block. Also, do you pull a toad? They can help alot in diagnosing leaks as well.
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« Reply #21 on: June 01, 2009, 06:22:18 AM »

Rick, fwiw not all the DD 8v71 or the 92 series had the check valves most have been added over the years    good luck
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RickB
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« Reply #22 on: June 01, 2009, 06:26:19 AM »

luvrbus,

I have drawings and pictures of them in my manuals so i assumed they were stock parts.

Thanks for the clarification.

Rick
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Blacksheep
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« Reply #23 on: June 01, 2009, 07:56:29 AM »

I have been out on about 5 trips since Central Florida bus repair did service on my Prevost with an 8v92 and it has yet to need oil added. Before I had to add at least a gallon every trip! Granted the last 5 trips were 300 miles or less each time but still that is saying something! The main leak was the turbo line!
Goes to show that oil leaks CAN be corrected!
Ace
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JohnEd
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« Reply #24 on: June 01, 2009, 10:45:29 AM »

Paul,

The first step is to properly/completely steam clean the entire engine and compartment.  This isn't wasted as after you find the leak a simple carwash sprayer will remove the "fresh" oil.  After washing the leaks can be traced to their source by following the trail.  I would let it idle with the doors open for a long while and look mightily afterwards with conviction.  At speed it gets blown around and that makes it harder to localize but they do it all the time.

Good luck with this and let us know how many and where the leaks are and how you resolve them.  I read a post that said that the oil seals in the head/block interface leak with age and nobody R&R's a head for a leak that isn't a gusher.

HTH,

John
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"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
—Pla
Dreamscape
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« Reply #25 on: June 01, 2009, 11:04:25 AM »

Thanks for the quick replys! I'll check the compression fitting and clean the beast up and see what else is leaking. Maybe that's all but I seriously doubt it! Grin

I don't pull a toad, yet anyway! I'm probably glad I don't tow anything until I get the bleeding stopped!


I'm still making cabinets, the boss has me busy! Cheesy

~Paul~
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Becky and Paul Lawry, On The Road
Travel Blog - http://dreamscapetravels.wordpress.com/
Bus Blog - http://dreamscapesilvereagle.wordpress.com/
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kingfa39
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« Reply #26 on: June 01, 2009, 11:20:43 AM »

John, the mech that told me and showed me about the leaks was Charley neal, he was in pinacle NC now deceased, he worked for greyhound for yrs and was a fine mech, he spent many hrs on his work making sure that every conection etc was perfect and when he rebuilt a engine it looked like something you could put in your living room, i used to live 15 miles from his garage, it was a real loss to many when he left us. But the bottom line is these engines do not have to leak, i looked at one he had done 10  yrs eairlier and it was dry as a bone. He also put the contraversial check valves on mine for the blower drains 20 yrs ago, never had a problem. now that Terry Bennett is out of the business and Charley is gone im at a loss as to who can do my work right as i have been ripped off several times in the past.
Frank Allen 4106
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JohnEd
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« Reply #27 on: June 01, 2009, 11:29:37 AM »

Frank,

I am grieving with you for both reasons.  So much knowledge and wisdom lost to the planet...there ought to be a law.  celestial!

John
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"An uneducated vote is a treasonous act more damaging than any treachery of the battlefield.
The price of apathy towards public affairs is to be ruled by evil men." Plato
“We can easily forgive a child who is afraid of the dark; the real tragedy of life is when men are afraid of the light.”
—Pla
johns4104s
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« Reply #28 on: June 01, 2009, 07:21:02 PM »

Richard,

Great rally ,great people , great food.

Did you pull a toad and get tat milage? What speed did you drive??

See you at the next Rally.

John
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