3FE Valve adjustment question

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S

Sand or Foam

10 Year
Joined
Aug 24, 2015
Threads
16
Messages
105
Location
Tacoma
upload_2015-12-4_20-42-33.webp

Trying to adjust the valves per FSM and when I have the TDC(2 small stacked dots) lined up and No.1 cylinder rocker arms are loose, I only have 1 rocker arm tight on No. 6. And the same is true when I spin 360, No. 6 is loose and only 1 rocker on No. 1 is tight.

Any ideas what would cause this? And they are not just barley loose, I can fit the corresponding feeler gauge in the rocker(after adjusting) that should not be loose but is...
 
Well, it should be like the FSM states as I've followed that method quite a few times. One more variable you could use to verify your at TDC No 1 on compression would be to pop the distributor cap off and see which plug the rotor is pointing to, I believe it should be the #1 plug (please correct me if I'm wrong). Assuming this all checks out, I'd just follow the procedure verbatim and you should be good.

Does your truck run currently?
 
As long as the cam lobe is up (not pressing on the rocker) it shouldn't matter where your engine is at. I will adjust the ones that are already up when I take the valve cover off, then turn the motor to get the rest.
 
Alleycats said:
Well, it should be like the FSM states as I've followed that method quite a few times. One more variable you could use to verify your at TDC No 1 on compression would be to pop the distributor cap off and see which plug the rotor is pointing to, I believe it should be the #1 plug (please correct me if I'm wrong). Assuming this all checks out, I'd just follow the procedure verbatim and you should be good.

Does your truck run currently?
Click to expand...

So my question was kind of loaded...my truck runs, but has a huge lack of power that I have been trying to figure out. I bought the truck running rough and thought it was all just PM related. After doing all the normal PM stuff and everything fuel related with exception of the pump(it tested fine) I finally did a compression test and found low numbers on all cylinders(90-110psi). With no improvement from an oil squirt and a leak down test pointing at valves, I pulled the head and had the valves and seats done. Machinist said all my exhaust valve seats were in bad shape and was not surprised at my lack of compression.

After getting it all back together, there was no change in compression. NONE! Valves were adjusted cold when I was putting it back together and again after I could warm it up. This is when I noticed the valves open did not match the FSM(No.1 vlaves open, No.6 has one tight one loose on TDC). I felt for pressure on the spark plug hole to verify I was on TDC compression, as well as checking the dist. rotor position.

While the head was off, I inspected the cylinder walls and could still see cross hatching and there was no ridge at the top of the cylinder.

I'm stumped. My dad threw out the idea that maybe my cam gear is off a tooth. I have never had the timing cover off and don't know the history. Thats what I am checking next and kind of my last hope. Any and all Ideas are welcome.

Thanks for all the links and help.
 
CRSHR said:
As long as the cam lobe is up (not pressing on the rocker) it shouldn't matter where your engine is at. I will adjust the ones that are already up when I take the valve cover off, then turn the motor to get the rest.
Click to expand...

I totally agree. And when I check clearances with no pressure on the rocker, it checks OK.

I guess I am wondering if there might be a reason that my rockers do not follow what the FSM says. And if that reason might be due to a cam that is not properly aligned? I am building a puller to get the crank pulley off, just need to find the time(wife and baby make this part tough).

Maybe I am more hoping this is it because that would explain my low compression, lack of power, etc. after trying everything else.

Or my bottom end is blown and I need to yank the motor.:bang:
 
I would recommend using another compression tester at this point. I think it may be inaccurate from what you are describing. Best to rule it out before you throw any more money or time at it.
 
CRSHR said:
I would recommend using another compression tester at this point. I think it may be inaccurate from what you are describing. Best to rule it out before you throw any more money or time at it.
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That's a good point, but I have used this tester on several cars in the past. And even checked a known good engine, 91 318i that had ~210psi across the board. Right where is should be.
I guess it wouldn't hurt to try another compression tester just to be 100%.
 
CRSHR said:
I had one go bad on me and was having some oddball low readings.
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Bringing this back from the dead. Had to take a break for the holidays and all that.

Used a brand new compression tester and got the same results +/-3psi.

I will pull the timing cover this week to verify timing gears are correct.
 
So your HG is toast?
 
I'm being slightly sarcastic - have you driven other 3fe land cruisers? Extreme lack of power is what they do best!

Next I would give a leak down compression test a shot - that will help narrow down which valves are the culprit (if it turns out to be the valves).

Correct me if I'm wrong, but I believe the 3fe is a timing gear - and it's gears have a matchmark to determine if they're lined up correctly. It shouldn't take too much effort to remove the timing cover to take a peek.


EDIT: Looking at the FSM, there are gears - and they do have a mark to ensure alignment. It's not a particularly easy job however.
 
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Mixelplix said:
I'm being slightly sarcastic - have you driven other 3fe land cruisers? Extreme lack of power is what they do best!

Next I would give a leak down compression test a shot - that will help narrow down which valves are the culprit (if it turns out to be the valves).

Correct me if I'm wrong, but I believe the 3fe is a timing gear - and it's gears have a matchmark to determine if they're lined up correctly. It shouldn't take too much effort to remove the timing cover to take a peek.


EDIT: Looking at the FSM, there are gears - and they do have a mark to ensure alignment. It's not a particularly easy job however.
Click to expand...

Yup, timing gears. And I am half way there to getting the timing cover off. Got the big 46mm crank nut off, now I just need to fab a puller to get the pulley off the crank.

Edit: And I know the 3fe is not know for it's blazing speed, but I crawl from a start and if the grade is too steep, I never get above 10mph.
 
The 3FE is slow I'll be the first to admit, but it does have Grunt down low.
 
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