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pszikszai
12-09-2005, 03:55 PM
I rebuilt a 259 and the plugs get oil fould after a few minutes of running.
I used cast iron rings.
New heads and new valves.
I noticed that the oil gauge fluctuates a little when
I revve it up.
Oil pressure is 40 t0 80 punds.
When I took the carb off, I noticed that there is oil
in the intake manifold.

I rebuilt many of these, but I have never encountered
anything like this.
Anyone help would be appreciated.
Paul

N8N
12-09-2005, 04:05 PM
sounds like you are getting a lot of oil in the lifter valley for some reason and it is getting sucked up into the PCV valve (the oil in the intake is the key here.) Did you have the rocker shafts rebuilt when you rebuilt the engine? If not you may want to consider restricting the oil flow to the heads.

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

Roscomacaw
12-09-2005, 04:19 PM
Along the vein that N8N's started, maybe there's plugged drains for the heads.

Are ALL EIGHT plugs fouled??

This thing must SMOKE something AWFUL, no[?]

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1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

N8N
12-09-2005, 04:37 PM
one more thought - if the engine is "tight" but that little plug is left out behind the distributor, could that be causing the problem? I would expect lower oil pressure, but you never can tell.

Do you have a baffle under your PCV valve? (the finned aluminum valley covers don't have a baffle; I don't have a problem with that but I can't say that that would be true for all engines.)

nate

--
55 Commander Starlight
62 Daytona hardtop
http://home.comcast.net/~njnagel

Dwain G.
12-09-2005, 06:31 PM
The oil pressure should increase with increased rpm, that's normal.
Were the cylinders rebored to an oversize, and if so did they sell you the correct oversize rings? If the cylinders were not rebored were they measured for wear or for previous rebore?

Dwain G.

pszikszai
12-10-2005, 02:16 PM
Problem solved.
Thank you all for the help.
N8N correctly diagnosed the problem - thanks.
I need to replace the PCV valve - anyone know if there is one
that I can buy from an auto parts store that would be a close match
to the old stude one?

Roscomacaw
12-10-2005, 02:33 PM
Which "diagnosis" was it? No baffle or the plug left out?[?]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS

pszikszai
12-10-2005, 02:36 PM
Oil was sucked in thru the old PCV valve.

Roscomacaw
12-10-2005, 03:22 PM
Well then, Nate's point was that there should be no oil there for that PCV valve to "suck up". He asked if the lifter valley cover has a "baffle" on it's bottom. Said baffle is there to keep oil from reaching the bottom of the PCV valve (or road draft tube - if that's what you have to vent crankcase pressure.
There WERE some valley covers produced without the baffle because they were used on engines (R-series) that vented crankcase pressure elsewhere.
If you've got oil going thru your PCV, it's not the valve's fault![V]

Miscreant at large.

1957 Transtar 1/2ton
1960 Larkvertible V8
1958 Provincial wagon
1953 Commander coupe
1957 President 2-dr
1955 President State
1951 Champion Biz cpe
1963 Daytona project FS