Author Topic: 8V-71N "Normal" Oil Consumption?  (Read 4497 times)

Offline sparkplug188

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Re: 8V-71N "Normal" Oil Consumption?
« Reply #15 on: November 02, 2014, 11:04:30 AM »
Why is that so?  The oil pump should be moving the same volume of oil regardless of oil level.  Does adding that last quart of oil cause the crankshaft to splash excess oil onto the cylinder walls?  I am not doubting you-- many people have said the same thing... just curious.
« Last Edit: November 02, 2014, 11:06:33 AM by sparkplug188 »

Online luvrbus

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Re: 8V-71N "Normal" Oil Consumption?
« Reply #16 on: November 02, 2014, 12:31:54 PM »
Most of the time when the old 2 strokes blow the oil out there is to much by pass on the compression causing the oil to foam and they suck it out from bad pin seals 

I never run one a gal low it causes the oil temperature to rise if it blows the 1st gal out there is problem somewhere could be simple like the engine ventilation no one ever cleans the vent on the back of the engine on a old 71 series I have had to dig the dirt from those before a air compressor was no use     
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Offline Scott & Heather

  • Scott & Heather's buses: MCI-9 & MCI-102
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Re: 8V-71N "Normal" Oil Consumption?
« Reply #17 on: November 02, 2014, 01:45:42 PM »
My bus has a nice little 2 gallon holding barrel mounted to the engine that i can fill (has a sight glass) and then use a valve to add oil as needed. very cool, very handy.
Scott & Heather
1984 MCI 9 6V92-turbo with 9 inch roof raise (SOLD)
1992 MCI 102C3 8v92-turbo with 8 inch roof raise CURRENT HOME
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Offline Debo

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Re: 8V-71N "Normal" Oil Consumption?
« Reply #18 on: November 02, 2014, 03:01:01 PM »
Thanks so much for the great answers guys. After reading tons of stuff including your comments, I'm thinking I'll be fine with the 3-gallon case I bought for the trip. I haven't seen anything crazy in terms of consumption on my shorter trips, and my engine is in pretty good shape. I'll be on I-95 for a lot of the trip, so it'll probably be much easier to find straight 40-weight along the way than it was to get it here. I doubt I'll need it, but I'll probably pick some up because it's available. Before even reading about it here, I had noticed that my engine likes to run with the oil level slightly above the fill line on the dipstick. Anything above that disappears before too long, but it never gets any lower than that mark. That must be the "sweet spot" you guys are talking about. Scott - I've read about the oil reservoir in my parts book. Pretty cool. I kinda wish mine had that.

Thanks again for the great answers. After a few years on the board, I've found that the way to get people talking is to ask 'em about anything related to oil.  :D
« Last Edit: November 02, 2014, 03:02:35 PM by Debo »
1981 MCI MC9
Detroit 8V-71N
Spicer 4-Speed Manual
Outer Banks, NC (Nags Head)