problem with blue smoke

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68impalass
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problem with blue smoke

Unread post by 68impalass » September 16th, 2020, 12:12 pm

good afternoon, I have a problem with my A2. I started seeing blue smoke from the tailpipe when I would slow down and then restart. So I thought valve seals. After installing seals, there was no change.The rocker arms, etc. looked brand new and clean. So with a new head in stock I went ahead and installed it thinking possibly the valve stems were worn. Same smoke. Then comes the compression check. All cylinders read from 60-65 lbs. So out comes the engine. Looking at the bores the hone marks will still visible but there was a lot of glaze on the walls, so new rings were installed by the book and engine was reinstalled. Ran good for a time and then smoke started again. I happened to look at oil pressure and it was in the 60-65 lb. range even at idle. I installed a direct reading gauge and it read the same. Question is could this high oil pressure cause a smoking problem? thanks for looking
m151A2-have
M37-gone
m151A1-gone
M1009-gone
m275-gone
MEP17A-have
MEP16C-have

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rickf
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Re: problem with blue smoke

Unread post by rickf » September 16th, 2020, 12:30 pm

Are the oil tubes for the rocker arms seated on their holes and o-rings good? Thinking oil spraying and being picked up by the PCV system. Long shot but something to check. Have you serviced the air filter and made sure it has the correct amount of oil in it? 65 lbs. of oil pressure will not cause smoke but be sure to use a quality oil filter. A cheapo could burst on you. What oil are you using? Holding the same pressure even when hot indicates heavy oil or extremely tight engine. How many miles on the bottom end?
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

68impalass
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Re: problem with blue smoke

Unread post by 68impalass » September 16th, 2020, 12:48 pm

I use Rotella 15w40. while I had the engine out I checked the rod and mains, no wear on them at, this marine A2 shows 23,000 miles and i have no reason to believe otherwise, Brant tells me the same. I will check that o-ring . thanks Rick. Oh, I am using a PH_8A from fram
m151A2-have
M37-gone
m151A1-gone
M1009-gone
m275-gone
MEP17A-have
MEP16C-have

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rickf
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Re: problem with blue smoke

Unread post by rickf » September 16th, 2020, 5:53 pm

I have my opinions about Fram and they are all bad. The case is strong and will not let go on you but the filter media really sucks on the Frams. It has been well documented in many tests. I only use Wix filters in anything I run. Napa uses, or used Wix filters but I prefer to just get Wix branded so I know for sure. Good choice of oil.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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Mr. Recovery
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Re: problem with blue smoke

Unread post by Mr. Recovery » September 16th, 2020, 7:05 pm

Any of them will let go if the oil pump bypass is rusted closed ! :roll:
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1960 M151 Run 1
1963 M151 Willys DoD 10-63 in Baltimore
1989 Alley Cat. "work in Progress"
NRA Life Member
American Legion Post 275 Fl
US Army 6 years 2nd Armored Cavalry Bindlach Germany
Colorado Army Nat. Guard 5 years
Md Air Guard 15 years active duty on C-130's

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rickf
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Re: problem with blue smoke

Unread post by rickf » September 16th, 2020, 7:39 pm

This is true BUT, in that case the oil pump can produce several hundred lbs. pressure or higher. No filter is standing up to that. I doubt that is your problem. If the pressure does not rise above the 60 lbs. if you race the engine then the bypass is working.
1964 M151A1
1984 M1008
1967 M416
04/1952 M100
12/1952 M100- Departed
AN/TSQ-114A Trailblazer- Gone

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svramselaar
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Re: problem with blue smoke

Unread post by svramselaar » September 19th, 2020, 5:51 am

hi

i was thinking if it is posseble
if the seal inside the feul pump at the lever is bad (not the membrane)
the pump works fine bud can the engine suck oil vapour to the intake trow the vent line
if so we get blue smoke

george

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