Post by tuffytractor on Feb 8, 2008 0:32:54 GMT -5
After a few trials and tribulations, here it is!
Just to cover a few of the bases, that I overlooked in my attempt at my valve lash adjustments, confirm your assumptions about your motor before you begin. What is the rotation of your motor. I turned off the fuel and made sure the kill cable was pulled and set, then bumped the starter, good the motor turns in the clockwise direction while standing at the front.
This procedure should be done on an over night cold engine, so put the FEL up the day before your going to actually adjust.
Which valve is what? I assumed, mistakenly, that the valve closest to the radiator was the intake, it wasn't, ended up with a bunch of invalid readings the first time through, due to that assumption. Finally, after talking with Ronald over at Ranch Hand, realized I didn't know for sure. Pulled a glow plug and opened a valve and squirted compressed air through and realized I had it backwards. That helped a lot! After getting myself straightened out, things went much better. Lets walk through my process with some pictures to help illustrate.
First the safety precautions. Parking brake on, in neutral. Support the bucket, in my case I had the bucket up in the air for about 4 days, because of problems I inadvertently caused during the process. I used 1.5"X2.5"X10' 1/8 wall tubing I had for the support. Plumbed and leveled it to make sure it could take whatever strain it encountered, I'm sure the bleed off gave it some weight over that period of time.
Then made sure the fuel was turned off.
Then made sure the kill cable was secured.
Then propped back the hood. So I could have unobstructed access.
Then undid the compressor linkage.
Then removed the mount for the compressor linkage on the drivers side of the valve cover. I didn't know better, but you don't have to do this, the link will slide right up without removal. (Be careful to tilt the valve cover toward the drivers seat as you remove it, to keep the key from dropping out) Makes it mush easier and faster not to remove the compressor linkage mount from the exterior of the valve cover.
In these photos I have it reversed so you can see how the pin in the compression release keeps the compression release from over torquing the release lever during engagement. Remove the re-breather hose, connecting the valve cover to the intake. (sorry no picture)
I was able to get a socket (27mm) and ratchet onto the crankshaft for spinning the motor in a clock wise direction. (at this point you know which way you are spinning the motor because you confirmed it by bumping the starter, after the fuel was shut off and the kill switch pulled) I found that I needed to pull the alternator cover off to give me good throw with the ratchet for rotation.
In this photo the radiator is on the right and the drivers seat is to the left. You can just make out the 485 stamped into the head & the YD (yangdong?)485 in the exhaust. The first valve in is the exhaust valve, contrary to a lot of information posted on various other sites, the compression release activates the intake valves. The easiest way to prove this, is to pull the first cylinder's glow plug (12mm socket). Be careful not to loose the small washers on the bus bar and the copper squash washer at the bottom of the glow plug.
Use a small wrench to activate the compression release, to make it easier to rotate the engine
With the glow plug out rotate the motor until either valve of the #1 cylinder is open (valve pushed down), now blow some compressed air through the glow plug opening with one hand and use the other to feel where the air is escaping, the exhaust or the intake. You've just found out which valve is which, for sure. (This tip comes by way of Ronald at Ranch Hand, sure saved me). Now is a good time to rotate through the rack and get some preliminary readings of what your valves are set at currently, while getting familiar with the sequence that the valves open and close. Finding TDC (Top Dead Center) is accomplished by rotating the motor in a CW direction until the #1 Cylinder intake valve has closed (your are now at BDC) and then rotating another 180º (now you are at TDC). An easy way to be able to see that on the harmonic balancer (the crankshaft pulley) is to mark the pulley when the valve closes BDC with blue tape, on this engine it makes it easier because there is a pointer that extends to the face of the harmonic balancer. (I took the shot before I put my blue tape on)
My initial readings for the valves as they were set by the factory, were as follows:
#1 Exhaust .305mm
#1 Intake .305mm
#2 Exhaust .356mm
#2 Intake .203mm
#3 Exhaust .203mm
#3 Intake - to tight to measure
#4 Exhaust .305mm
#4 Intake .203 mm
Next we'll pull the Rocker Arm arm assembly and check the head bolts for proper torque and then set the rack to the proper settings. Remove the stud nuts from the valve cover studs and remove the bolts from the rocker arm assembly, watch the washers, not good to loose them in the head. Next mark the head bolts to see if tightening them has any effect, I used a gray colored sharpie.
I didn't have a manual to double check the torque for this head, I went with 125 ft lbs.
There is much discussion about how to establish good torque readings, the one thing that everyone does agree on, is that the bolt must be broken loose, then re-torqued to the proper setting to get a good reading. The debate rages as to what the best way is, break free, then pull the bolt out and lube the threads and then torque down or break free by one turn and then crank it back down. I've come to believe that lubing the threads does not give the best measure of torque (of course, I'm a shade tree mechanic, **please note disclaimer**). Torque is most often talked about when bolt strength and parent material is known, under dry condition. Adding lubricant can influence/create the same torque results with as little as half the torque pressure. So, just to keep things simple, I didn't do it that way. In addition, Ronald from Ranch Hand didn't recommend adding lubrication either. This site was helpful to me in establishing some of the parameters for good torque decisions.
www.futek.com/boltcalc.aspx?mode=metric
As it turns out, only one of my head bolts exhibited any signs of getting tighter, rotating an additional 1/16" upon re-torque.
Now, remount the rocker arm assembly (the rack). A word of caution at this point, I didn't know what to use as a torque setting for this procedure and brought myself quite a bit of difficulty by over torquing these poor little 8mm studs/bolts. Because they have lock washers the torque necessary to set or engage the lock washers is as little as 130" (read inch pounds, not foot pounds) thats only 11 ft lbs. In doing my research, after pulling the threads off the studs by applying to much torque, did I realize I had assumed that 65 ft lbs was the correct torque. In that situation, the person was using 12mm bolts, not 8mm bolts. As I mentioned I didn't have a manual to refer to so I went with 20 ft lbs to secure the rocker arm assembly to the head.
Then began running the rack. ;D
After calling my importing dealer and getting Ronald's opinion once more. I decided the proper settings to be:
Intake .356mm
Exhaust .406mm
The area I use my tractor in gets quite hot during the summer, this last summer we had three weeks in a row of over 110º weather. During those periods, working the tractor hard, with the metal heating up and expanding, those gaps will shrink and become tighter. Conversely, if I set them too loose, the motor will have a rattle to it. After talking to as many people as I could, I felt comfortable these gaps would give me the best overall performance.
A few pointers about the settings. Take your time, adjust, try it, nice smooth drag, not to heavy, not to light, just right, then tighten it up, check it again, still good? Then move on. Making sure that for every cylinder you are at TDC as described in the beginning of this post.
Before you begin, make sure the valve cover gasket thats in your extra parts kit is the one for your motor, as it turns out mine wasn't. The good news is that mine came up clean, didn't need to have one, this time, you may not be that lucky. If you can't get a ratchet into the opening on your crank and radiator cowling, you can use the alternator nut by tightening up the belt, to prevent slippage. Just make sure you remember to bring it back down to about 3/8" to 1/2" deflection after the procedure, or you may burn out the bearings for the water pump or alternator.
Then re-assemble everything, take care of the glow plug re-insertion before mounting the valve cover, much easier to get your hands in without dropping those pesky washers and a socket won't fit over the glow plug with the valve cover installed.
Now that you know what kind of pressure the compression release lever requires, you should have a much easier time using it during start-ups for pre-lube. Don't forget to hook it back up, along with the re-breather hose, wiring for the bus bar and if you took it off, for the horn.
Make sure you pulled the socket off the crank, all the tools clear? Lets crank this baby up!
Wow, she pulls right up to max RPM, sounds like a sewing machine on steroids, very sweet!
Then... if you have any extra bling..., now is the time. Like a customized Alternator cover and (drum roll.... ) Brand New, Freshly Fabricated from the quintessential customizer, quickduk...... Radiator Over-Flow Tank and Mounting Bracket!!! Wow isn't' that terrific! Big thanks Ken, looks awesome.
One last thought, this post is intended for those of you out there that are not quite sure, but want to have a good running little tractor, you can do it, I didn't think I'd get through it, but I did and so will you.
For those of you with good or great mechanical skills, I hope you didn't find this post to slow.
Just to cover a few of the bases, that I overlooked in my attempt at my valve lash adjustments, confirm your assumptions about your motor before you begin. What is the rotation of your motor. I turned off the fuel and made sure the kill cable was pulled and set, then bumped the starter, good the motor turns in the clockwise direction while standing at the front.
This procedure should be done on an over night cold engine, so put the FEL up the day before your going to actually adjust.
Which valve is what? I assumed, mistakenly, that the valve closest to the radiator was the intake, it wasn't, ended up with a bunch of invalid readings the first time through, due to that assumption. Finally, after talking with Ronald over at Ranch Hand, realized I didn't know for sure. Pulled a glow plug and opened a valve and squirted compressed air through and realized I had it backwards. That helped a lot! After getting myself straightened out, things went much better. Lets walk through my process with some pictures to help illustrate.
First the safety precautions. Parking brake on, in neutral. Support the bucket, in my case I had the bucket up in the air for about 4 days, because of problems I inadvertently caused during the process. I used 1.5"X2.5"X10' 1/8 wall tubing I had for the support. Plumbed and leveled it to make sure it could take whatever strain it encountered, I'm sure the bleed off gave it some weight over that period of time.
Then made sure the fuel was turned off.
Then made sure the kill cable was secured.
Then propped back the hood. So I could have unobstructed access.
Then undid the compressor linkage.
Then removed the mount for the compressor linkage on the drivers side of the valve cover. I didn't know better, but you don't have to do this, the link will slide right up without removal. (Be careful to tilt the valve cover toward the drivers seat as you remove it, to keep the key from dropping out) Makes it mush easier and faster not to remove the compressor linkage mount from the exterior of the valve cover.
In these photos I have it reversed so you can see how the pin in the compression release keeps the compression release from over torquing the release lever during engagement. Remove the re-breather hose, connecting the valve cover to the intake. (sorry no picture)
I was able to get a socket (27mm) and ratchet onto the crankshaft for spinning the motor in a clock wise direction. (at this point you know which way you are spinning the motor because you confirmed it by bumping the starter, after the fuel was shut off and the kill switch pulled) I found that I needed to pull the alternator cover off to give me good throw with the ratchet for rotation.
In this photo the radiator is on the right and the drivers seat is to the left. You can just make out the 485 stamped into the head & the YD (yangdong?)485 in the exhaust. The first valve in is the exhaust valve, contrary to a lot of information posted on various other sites, the compression release activates the intake valves. The easiest way to prove this, is to pull the first cylinder's glow plug (12mm socket). Be careful not to loose the small washers on the bus bar and the copper squash washer at the bottom of the glow plug.
Use a small wrench to activate the compression release, to make it easier to rotate the engine
With the glow plug out rotate the motor until either valve of the #1 cylinder is open (valve pushed down), now blow some compressed air through the glow plug opening with one hand and use the other to feel where the air is escaping, the exhaust or the intake. You've just found out which valve is which, for sure. (This tip comes by way of Ronald at Ranch Hand, sure saved me). Now is a good time to rotate through the rack and get some preliminary readings of what your valves are set at currently, while getting familiar with the sequence that the valves open and close. Finding TDC (Top Dead Center) is accomplished by rotating the motor in a CW direction until the #1 Cylinder intake valve has closed (your are now at BDC) and then rotating another 180º (now you are at TDC). An easy way to be able to see that on the harmonic balancer (the crankshaft pulley) is to mark the pulley when the valve closes BDC with blue tape, on this engine it makes it easier because there is a pointer that extends to the face of the harmonic balancer. (I took the shot before I put my blue tape on)
My initial readings for the valves as they were set by the factory, were as follows:
#1 Exhaust .305mm
#1 Intake .305mm
#2 Exhaust .356mm
#2 Intake .203mm
#3 Exhaust .203mm
#3 Intake - to tight to measure
#4 Exhaust .305mm
#4 Intake .203 mm
Next we'll pull the Rocker Arm arm assembly and check the head bolts for proper torque and then set the rack to the proper settings. Remove the stud nuts from the valve cover studs and remove the bolts from the rocker arm assembly, watch the washers, not good to loose them in the head. Next mark the head bolts to see if tightening them has any effect, I used a gray colored sharpie.
I didn't have a manual to double check the torque for this head, I went with 125 ft lbs.
There is much discussion about how to establish good torque readings, the one thing that everyone does agree on, is that the bolt must be broken loose, then re-torqued to the proper setting to get a good reading. The debate rages as to what the best way is, break free, then pull the bolt out and lube the threads and then torque down or break free by one turn and then crank it back down. I've come to believe that lubing the threads does not give the best measure of torque (of course, I'm a shade tree mechanic, **please note disclaimer**). Torque is most often talked about when bolt strength and parent material is known, under dry condition. Adding lubricant can influence/create the same torque results with as little as half the torque pressure. So, just to keep things simple, I didn't do it that way. In addition, Ronald from Ranch Hand didn't recommend adding lubrication either. This site was helpful to me in establishing some of the parameters for good torque decisions.
www.futek.com/boltcalc.aspx?mode=metric
As it turns out, only one of my head bolts exhibited any signs of getting tighter, rotating an additional 1/16" upon re-torque.
Now, remount the rocker arm assembly (the rack). A word of caution at this point, I didn't know what to use as a torque setting for this procedure and brought myself quite a bit of difficulty by over torquing these poor little 8mm studs/bolts. Because they have lock washers the torque necessary to set or engage the lock washers is as little as 130" (read inch pounds, not foot pounds) thats only 11 ft lbs. In doing my research, after pulling the threads off the studs by applying to much torque, did I realize I had assumed that 65 ft lbs was the correct torque. In that situation, the person was using 12mm bolts, not 8mm bolts. As I mentioned I didn't have a manual to refer to so I went with 20 ft lbs to secure the rocker arm assembly to the head.
Then began running the rack. ;D
After calling my importing dealer and getting Ronald's opinion once more. I decided the proper settings to be:
Intake .356mm
Exhaust .406mm
The area I use my tractor in gets quite hot during the summer, this last summer we had three weeks in a row of over 110º weather. During those periods, working the tractor hard, with the metal heating up and expanding, those gaps will shrink and become tighter. Conversely, if I set them too loose, the motor will have a rattle to it. After talking to as many people as I could, I felt comfortable these gaps would give me the best overall performance.
A few pointers about the settings. Take your time, adjust, try it, nice smooth drag, not to heavy, not to light, just right, then tighten it up, check it again, still good? Then move on. Making sure that for every cylinder you are at TDC as described in the beginning of this post.
Before you begin, make sure the valve cover gasket thats in your extra parts kit is the one for your motor, as it turns out mine wasn't. The good news is that mine came up clean, didn't need to have one, this time, you may not be that lucky. If you can't get a ratchet into the opening on your crank and radiator cowling, you can use the alternator nut by tightening up the belt, to prevent slippage. Just make sure you remember to bring it back down to about 3/8" to 1/2" deflection after the procedure, or you may burn out the bearings for the water pump or alternator.
Then re-assemble everything, take care of the glow plug re-insertion before mounting the valve cover, much easier to get your hands in without dropping those pesky washers and a socket won't fit over the glow plug with the valve cover installed.
Now that you know what kind of pressure the compression release lever requires, you should have a much easier time using it during start-ups for pre-lube. Don't forget to hook it back up, along with the re-breather hose, wiring for the bus bar and if you took it off, for the horn.
Make sure you pulled the socket off the crank, all the tools clear? Lets crank this baby up!
Wow, she pulls right up to max RPM, sounds like a sewing machine on steroids, very sweet!
Then... if you have any extra bling..., now is the time. Like a customized Alternator cover and (drum roll.... ) Brand New, Freshly Fabricated from the quintessential customizer, quickduk...... Radiator Over-Flow Tank and Mounting Bracket!!! Wow isn't' that terrific! Big thanks Ken, looks awesome.
One last thought, this post is intended for those of you out there that are not quite sure, but want to have a good running little tractor, you can do it, I didn't think I'd get through it, but I did and so will you.
For those of you with good or great mechanical skills, I hope you didn't find this post to slow.
