hi, i finally attempted to adjust my valves today on my 1971 fj40, i just hope i did it right. i used my haynes manual at first. it said that i could get the truck warmed up and then align top dead center mark with the pointer, and rotor with plug one, then adjut half of the valves (like 1,2,3,5,7,9 or somthing). i could not find a tdc mark as pictured in the maual, but i did find the ball bearing which seemed to be tdc but i think i remember it being somthing like 8degres off. anyway i aligned the pointer with the ball bearing and rotor with plug one and adjusted all the valves it listed. then it said to rotate the motor 360 degrees and adjust the rest. i turned it 360 but the valves it said to adjust were not all closed so i couldnt adjust them. so i just turned the motor until the valve i was adjusting was closed and finished each one that way. does this sound ok or have i done somthing very wrong? the motor actually sounds a little louder now as far as the sewing machine noise goes. it all sounds healthy exept i think i hear one ticking noise sticking out amound the others, but im not exactly sure? is all of this normal or ok?
Valve adjustment done right?
- Thread starter staplebus
- Start date
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Almost, but not quite, grasshopper.
First part sounds OK, but you really should find and clean your TDC mark (7 degrees behind the BB).
You turned the engine 360? How? How do you know it was 360? Where was the rotor pointing when you adjusted the second set of valves? At #1?
This is hard the first time, but when you know the secret, you can do it blindfolded.
First part sounds OK, but you really should find and clean your TDC mark (7 degrees behind the BB).
You turned the engine 360? How? How do you know it was 360? Where was the rotor pointing when you adjusted the second set of valves? At #1?
This is hard the first time, but when you know the secret, you can do it blindfolded.
- Thread starter
- #3
yeah i turned it so that the rotor went arond 360 and back to #1 and the second half of the valves were not where they were supposed to be, i dont know why, maybe thats not how your supposed to do it? ...and since i did the first half of the valves at 7 degrees behind tdc should i redo the all of them? ...or is there enough "time" between 7btdc and tdc that the valves would stay shut.
- Thread starter
- #4
i did the "second set of valves" by turning the motor and watching each individual valve close and then adjusting them as they closed, the rotor was not pointed in one direction as i had to turn the motor a few times.
By your second post, it seems that you're acutally spinning the engine 720 degrees, not 360. At 360, the TDC mark will come into the window, but the rotor will not be pointing at number 1, but at number 6, I think. For every revolution of the distributor, the engine turns two revolutions.
The scribe line for TDC is an inch or so behind the ball bearing mark. If you rotate the engine in the direction it rotates, then the ball bearing comes into the window first, then the scribe line behind it. This thread has a drawing from the manual.
The procedure you describe is essentially it, except you do want to be at TDC (the scribe line, not 7 deg BTDC which is where the ball bearing mark is). I get the engine hot, then turn it off and remove the plugs and valve cover. I rotate the engine TDC with #1 on the compression stroke. I then adjust the exhaust valves for cylinders 1, 3 & 5. I then adjust the intake valves for cylinders 1, 2 & 4. I rotate the crank/flywheel 360 degees (one time around back to the TDC mark) and adjust the intake valves for cylinders 3, 5 & 6. Finally adjust the exhaust valves for cylinders 2, 4 & 6.
I hope this doesn't get confusing...I use the attached table and count out the valves one by one from the front of the engine. I do the a's first, then the b's, then rotate the engine then the c's and d's. This way I don't have to figure out which valve is exhaust and which is intake for a given cylinder, I just count from the front valve: 1, 5, 9, then 2, 3, 7 then 6, 10, 11, then 4, 8, 12.
The scribe line for TDC is an inch or so behind the ball bearing mark. If you rotate the engine in the direction it rotates, then the ball bearing comes into the window first, then the scribe line behind it. This thread has a drawing from the manual.
The procedure you describe is essentially it, except you do want to be at TDC (the scribe line, not 7 deg BTDC which is where the ball bearing mark is). I get the engine hot, then turn it off and remove the plugs and valve cover. I rotate the engine TDC with #1 on the compression stroke. I then adjust the exhaust valves for cylinders 1, 3 & 5. I then adjust the intake valves for cylinders 1, 2 & 4. I rotate the crank/flywheel 360 degees (one time around back to the TDC mark) and adjust the intake valves for cylinders 3, 5 & 6. Finally adjust the exhaust valves for cylinders 2, 4 & 6.
I hope this doesn't get confusing...I use the attached table and count out the valves one by one from the front of the engine. I do the a's first, then the b's, then rotate the engine then the c's and d's. This way I don't have to figure out which valve is exhaust and which is intake for a given cylinder, I just count from the front valve: 1, 5, 9, then 2, 3, 7 then 6, 10, 11, then 4, 8, 12.
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i had this same problem, try it again. its also easier with three hands. right wes? 
- Thread starter
- #7
i will try it again, and this time i will make sure it is one the scribe line, but would it make a difference if it rotated the motor forwards vs backwards? becuase after i did the first set of valves i bumped the cruiser backwards in third gear to turn the motor? not sure if the direction matters as long as i line it up with the scribe line again?
i also i couldnt turn the motor by pulling on the belt even with the plugs removed(think i need to tighten my belt), is this the easy way to do it(remove plugs and pull on belt)? or is there and easy/other way besides pushing it in gear.
i also i couldnt turn the motor by pulling on the belt even with the plugs removed(think i need to tighten my belt), is this the easy way to do it(remove plugs and pull on belt)? or is there and easy/other way besides pushing it in gear.
- Thread starter
- #8
well i read those other threads and i guess it doesnt matter which direction i go 360, just need to know where pistion 1 is in relation to tdc, and i can adjust the two sets of valves by rotating 360 degrees respectively. i will try again tomorrow, it just so cold right now its hard keep the truck warmed up the whole time i am working on the valves. thanks again everyone and i will chime in again when run into other problems. ha!
It shouldn't matter if you turn the engine forward or backwards as long as you only turn the flywhee one rotation. On my FJ-60, I take the plugs out and I can turn the engine by putting a socket wrench on the alternator nut. Bumping the car works fine, or on an FJ-40, I assume you can use the hand crank for the engine. I like to remove, or at least loosen the plugs because both positions is TDC on the compression stroke for either #1 or #6, and the compressed gas in the cylinder fights you against keeping it at TDC.
Personally I dont like this method.
I use 'rule of 13'
Turn until a valve is fully open (say #1) 13-1 = 12 so adjust #12
repeat until all done.
a white paint pen or white out is good to mark the ones you've done.
I use 'rule of 13'
Turn until a valve is fully open (say #1) 13-1 = 12 so adjust #12
repeat until all done.
a white paint pen or white out is good to mark the ones you've done.
staplebus said:
This will work for adjusting any valve. Turn it until the valve comes up and stops and then keep turing it a few more degrees. This works because the valve spends nearly 3/4 of its cycle time closed and the valve clearance doesn't change during this period. There are lots of correct ways to adjust valves and if they are done properly, they all give the same result. It isn't rocket science anyway. +/- a couple of thousandths is fine.
