blowby??
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blowby??
I have a lot of blowby. before I try rings or
other prob, I replaced pcv valve. no difference,
The pcv valve goes into the base of the carb, could that part of the carb be plugged. I also have 2 spark plugs next to each other(oil coming out of sparkplug holes.
66 352 v8 f250
any ideas?
other prob, I replaced pcv valve. no difference,
The pcv valve goes into the base of the carb, could that part of the carb be plugged. I also have 2 spark plugs next to each other(oil coming out of sparkplug holes.
66 352 v8 f250
any ideas?
Posting Guru
Joined: Jul 1999
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From: Inthepast
blowby??
The PCV valve is designed to conduit any crackcase gases into the carb to be combusted. A stuck PCV valve or blocked carb port will prevent that from doing it's job. However, even a properly working PCV system will not evacuate all the gases from there if there is excessive crankcase pressure (if it's excessive then I agree that it's likely rings and a compression test may reveal some insight).
Remove the PCV valve while the truck is warmed up and idling. Pull the PCV and vacuum hose. Test for vacuum at the PCV valve. If you hear the "air sucking" through the valve and there also seems to be a lot of "smoke" pouring out the valve cover when idling, then suspect worn rings.
<font color="#f80732" size="4" face="Graphite Light">Stock Man
</font><font color="#0000FF" size="2" face="Graphite Light">1967 F-250 FE 390 4wd</font>
<font color="#0000FF" size="2" face="Graphite Light">1966 F-250 I6 240 2wd LWB Flare Side</font>
<a href="http://www.hometown.aol.com/tbeeee">http://www.hometown.aol.com/tbeeee</a>
Remove the PCV valve while the truck is warmed up and idling. Pull the PCV and vacuum hose. Test for vacuum at the PCV valve. If you hear the "air sucking" through the valve and there also seems to be a lot of "smoke" pouring out the valve cover when idling, then suspect worn rings.
<font color="#f80732" size="4" face="Graphite Light">Stock Man
</font><font color="#0000FF" size="2" face="Graphite Light">1967 F-250 FE 390 4wd</font>
<font color="#0000FF" size="2" face="Graphite Light">1966 F-250 I6 240 2wd LWB Flare Side</font>
<a href="http://www.hometown.aol.com/tbeeee">http://www.hometown.aol.com/tbeeee</a>
New User
Joined: Dec 1999
Posts: 8
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blowby??
I think you most likely have ring problems also. Sounds exactly like the old and tired motor that used to grace the engine compartment of my truck.
When I disassembled my engine, the oil ring in every cylinder had collapsed.
-Troy
RagTag's Classic F-100s
<a href="http://taintedweb.com/ragtag">http://taintedweb.com/ragtag</a>/
F-Series Truck Ring
<a href="http://taintedweb.com/truckring">http://taintedweb.com/truckring</a>/
When I disassembled my engine, the oil ring in every cylinder had collapsed.
-Troy
RagTag's Classic F-100s
<a href="http://taintedweb.com/ragtag">http://taintedweb.com/ragtag</a>/
F-Series Truck Ring
<a href="http://taintedweb.com/truckring">http://taintedweb.com/truckring</a>/
