Hello Mudders, I've trolled the site for a lot of info but this is my first post.
1974 FJ40 w/ F155 motor
I noticed milky oil building up in my oil fill cap, and in the PCV valve but not on my dipstick. I got the vehicle to operating temperature and did a dry compression test, followed by a "wet" test with a little oil down each cylinder.
Cylinder PSI w/oil
1 55 70
2 48 70
3 28 45
4 15 68
5 25 39
6 30 45
Spark plugs 1-3 were black with some build up on them, spark plugs 4-6 were clean with an ashy brown color.
I checked/adjusted the valves at the same time and found white milky oil sitting on top of the valve clearance adjusters over cylinders 1 and 2, and some inside the valve cover, but nowhere else. My coolant doesn't visually have any signs of oil contamination.
Obviously the compression numbers are very poor. The milky oil over cylinders 1 and 2, and in the PCV likely indicate a bad head gasket at best.
Am I likely looking at worn rings and a bad head gasket? Is there much chance that replacing the head gasket will remedy my compression problems too?
Based on the available info, I'm looking for opinions on a couple courses of action. I'm not interested in fully rebuilding the motor, I think I would rather spend the money to put in a 3FE.
Option 1: Replace head gasket and hope that it at least keeps the water out. But if it doesn't bring my compression up, how long can I run on such low compression while I save for a 3FE swap?
Option 2: Buy an F155 out of a 1973 FJ55 off Craigslist for $500 that was pulled because he was given a 2F. Unknown mileage but supposedly had good power and no smoke.
Link to ad:
1973 Landcruiser Drivetrain
What are the real chances that I install this motor and it's any better than what I've got?
Thats where my heads at right now, I'm bummed to have this come up just as I was getting ready to pull the hard top off for spring...
My cruiser and background info:
May 1974 built FJ40
F155, desmogged, with Weber 38, unknown mileage, supposedly rebuilt at some point by PO, 33x12.5 tires, otherwise mostly stock.
This is my first cruiser, and I've owned it for a little over a year. Always thought the power has been very poor, most noticeably when because I cannot maintain speed going up any inclines at highway speeds. It's been this way since I owned so I just figured it's how these things were. I get a lot of condensation (liquid and white smoke/vapor) upon startup and was told by a trusted source that it was just condensation collecting on cold steel and so I never worried too much about it. This was a gift to myself after leaving the service, which I bought to have something to learn and tinker on; so far I've been able to do just that.
Thanks for reading my ramblings and I appreciate your feedback.
1974 FJ40 w/ F155 motor
I noticed milky oil building up in my oil fill cap, and in the PCV valve but not on my dipstick. I got the vehicle to operating temperature and did a dry compression test, followed by a "wet" test with a little oil down each cylinder.
Cylinder PSI w/oil
1 55 70
2 48 70
3 28 45
4 15 68
5 25 39
6 30 45
Spark plugs 1-3 were black with some build up on them, spark plugs 4-6 were clean with an ashy brown color.
I checked/adjusted the valves at the same time and found white milky oil sitting on top of the valve clearance adjusters over cylinders 1 and 2, and some inside the valve cover, but nowhere else. My coolant doesn't visually have any signs of oil contamination.
Obviously the compression numbers are very poor. The milky oil over cylinders 1 and 2, and in the PCV likely indicate a bad head gasket at best.
Am I likely looking at worn rings and a bad head gasket? Is there much chance that replacing the head gasket will remedy my compression problems too?
Based on the available info, I'm looking for opinions on a couple courses of action. I'm not interested in fully rebuilding the motor, I think I would rather spend the money to put in a 3FE.
Option 1: Replace head gasket and hope that it at least keeps the water out. But if it doesn't bring my compression up, how long can I run on such low compression while I save for a 3FE swap?
Option 2: Buy an F155 out of a 1973 FJ55 off Craigslist for $500 that was pulled because he was given a 2F. Unknown mileage but supposedly had good power and no smoke.
Link to ad:
1973 Landcruiser Drivetrain
What are the real chances that I install this motor and it's any better than what I've got?
Thats where my heads at right now, I'm bummed to have this come up just as I was getting ready to pull the hard top off for spring...
My cruiser and background info:
May 1974 built FJ40
F155, desmogged, with Weber 38, unknown mileage, supposedly rebuilt at some point by PO, 33x12.5 tires, otherwise mostly stock.
This is my first cruiser, and I've owned it for a little over a year. Always thought the power has been very poor, most noticeably when because I cannot maintain speed going up any inclines at highway speeds. It's been this way since I owned so I just figured it's how these things were. I get a lot of condensation (liquid and white smoke/vapor) upon startup and was told by a trusted source that it was just condensation collecting on cold steel and so I never worried too much about it. This was a gift to myself after leaving the service, which I bought to have something to learn and tinker on; so far I've been able to do just that.
Thanks for reading my ramblings and I appreciate your feedback.
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Those compression numbers are dismal 
. I'm working on the 3FE swap now (along with a million other things) and it's a lot more involved and costly than swapping in another F or even a 2F.
