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Home » Public Forums » GMCnet » Oil Filters (The Cause of Blown Engines?)
Oil Filters [message #115818] Sun, 20 February 2011 11:55 Go to next message
Adrien G. is currently offline  Adrien G.   United States
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Registered: May 2008
Location: Burns Flat, OK 73624
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Senior Member
I've been reading here about Dan's blown engines (sorry your having this challenge again), and the roll of the cooler, filter, bypass valve, and whatever else comes to our mind as to the cause.

We have established that the oil flows from oil pan to pump, to oil cooler, to oil filter/bypass valve, to internal moving parts.

I read that the bypass valve requires 5 to 6 lbs to open. The oil pump will put out 40 to 80 lbs (depending on relief valve)with cold oil.

With that established, the question I'm thinking is, does the filter media create more or less back pressure then required to open the bypass?
If it's less then all the oil is filtered, if more then only a percentage is filtered (and some impurities can sneak through), then we need to look at increasing the filtering media area to decrease the back pressure, by bigger filter, multiple filters, increase bypass pressure or block bypass, or ?.

My thoughts on filters for now.


Adrien & Jenny Genesoto 75 Glenbrook (26-3) Mods LS3.70 FD / Reaction Sys / 80mm Front&Intermidiate / Hydroboost / 16" Tires / Frame Rebuild / Interior Rebuild Yuba City,Ca. Text 530-nine-3-three-3-nine-nine-6
Re: Oil Filters [message #115822 is a reply to message #115818] Sun, 20 February 2011 12:09 Go to previous messageGo to next message
roy1 is currently offline  roy1   United States
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Registered: July 2004
Location: Minden nevada
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I have a machinest friend that builds hi tech carburated ford engines for street machines. He doesn't trust just using the stock oil filter. He always adds a dual filter in the leaving oil between the oil pump and the oil cooler. This way he feels the cooler can't get contaminated and he doesn't have any concerns of an open bypass on warm up. To him this is cheap insurance for a very expensive engine. I would imagine it would be tough to find room for this filter system in our coaches.
Roy


Roy Keen Minden,NV 76 X Glenbrook
Re: Oil Filters [message #115891 is a reply to message #115818] Sun, 20 February 2011 17:49 Go to previous message
Craig Lechowicz is currently offline  Craig Lechowicz   United States
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Registered: October 2006
Location: Waterford, MI
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Lotsa fixin' going on for something that might not be broken. Somehow, my coach has made it 85,000 miles w/o 2 oil filters, and my Trailblazer 130,000 (which has an oil cooler as well) and many others have gone much farther. Maybe that 2nd oil filter would save you, if you had lots of things going through there that shouldn't be. If you don't have a bypass valve, maybe you'll blow the gasket out of it on warm up (used to happen all the time on our race car - the leak part, not the not noticing part - a crew member was assigned to watch the oil filter during warmup) and not notice the sudden loss of oil and get it shut down in time to save it. Maybe if you have 2 oil filters, the longer time to purge the air out of them on replacement (if you don't use a pre-oiler) will slowly cause enough dry startup wear to create a problem rather than cure one. Way too many maybe's for me to change but, just another opinion.

Craig Lechowicz
'77 Kingsley, Waterford, MI
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