Timing Belt How to...
Originally Posted by Soon2BEVO
Im planning on doing this soon as my car is at 57,000 miles. Im going to take a look at the HOW TO here. I had a 1990 AWD DSM so hopefully its similar.
On another note Id like to ask some people what they think about the parts I need.
I know I will definitely need:
Timing Belt
Balance Shaft Belt
Hydraulic Tensioner
Do I need to replace these???
TB Tensioner Pulley
TB Idler Pulley
BS Tensioner Pulley
On another note Id like to ask some people what they think about the parts I need.
I know I will definitely need:
Timing Belt
Balance Shaft Belt
Hydraulic Tensioner
Do I need to replace these???
TB Tensioner Pulley
TB Idler Pulley
BS Tensioner Pulley
Thread Starter
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From: Lafayette, LA (Da Bayou)
OK, my balance shaft "appears" to be 180 out of sync. I know that sounds funny. But it is really probably 360 degrees out of sync. There is a 720 degree (2 rotation) sync on that gear.
To understand better how to check it took me a little while to get a grasp on what was happening. Here are some important things to know.
Timing mark is at 9 o'clock.
The balance shaft makes 2 revolutions for every one crank rotation.
If this is off there will be a very slight but sharp vibration at 4k to 4.5k rpms.
I felt it after my belt swap but thought it was just new fluids or something. But it never went away. Then my starter failed. When changing it I noticed that my flywheel dust cover had split. Then my Alternator failed. The bolts vibrated out of it. My oil pan has had a problem with a slow oil leak which I thought was a bad gasket on my oil return line from the turbo. Then I shredded an accessory belt, then another...
So I started to do some research.. After speaking with others that have had balance shaft alignment issues it sounds like all the normal conditions for a balance shaft being 1 rotation off (180 out). So Next week I will be checking my balance shaft alignment.
How to check:
Timing mark on the block is 9 o'clock (remember)
Put the timing mark on the gear at 12 o'clock. Yes this is not where is should be to be in line. Now let go of the gear. It will fall either counter-clockwise, towards the timing mark on the block or it will fall clock-wise away from the timing mark on the block.
If it spins/falls/rotates toward the 9 o'clock mark = it is in phase and rotate it counter clockwise 90 degrees to the timing mark and you should be on the money.
If it spins/falls/rotates away the 9 o'clock mark = it is out of phase. Rotate it clockwise 270 degrees to the timing mark and you should be on the money.
To understand better how to check it took me a little while to get a grasp on what was happening. Here are some important things to know.
Timing mark is at 9 o'clock.
The balance shaft makes 2 revolutions for every one crank rotation.
If this is off there will be a very slight but sharp vibration at 4k to 4.5k rpms.
I felt it after my belt swap but thought it was just new fluids or something. But it never went away. Then my starter failed. When changing it I noticed that my flywheel dust cover had split. Then my Alternator failed. The bolts vibrated out of it. My oil pan has had a problem with a slow oil leak which I thought was a bad gasket on my oil return line from the turbo. Then I shredded an accessory belt, then another...
So I started to do some research.. After speaking with others that have had balance shaft alignment issues it sounds like all the normal conditions for a balance shaft being 1 rotation off (180 out). So Next week I will be checking my balance shaft alignment.
How to check:
Timing mark on the block is 9 o'clock (remember)
Put the timing mark on the gear at 12 o'clock. Yes this is not where is should be to be in line. Now let go of the gear. It will fall either counter-clockwise, towards the timing mark on the block or it will fall clock-wise away from the timing mark on the block.
If it spins/falls/rotates toward the 9 o'clock mark = it is in phase and rotate it counter clockwise 90 degrees to the timing mark and you should be on the money.
If it spins/falls/rotates away the 9 o'clock mark = it is out of phase. Rotate it clockwise 270 degrees to the timing mark and you should be on the money.
Originally Posted by kjewer1
To avoid having to *** around with the screwdriver hole thing to make sure the rear balance shaft is in phase, put the timing mark on the oil pump sprocket at 12 oclock. If it rotates toward the mark on the case, it's in phase. If it rotates away from the mark, turn it one full turn. This is an old DSM trick that works on the EVO too.
Having the balance shafts out of phase is much worse than having no balance shafts at all...
Newb...
Originally Posted by Cajun Power
OK, my balance shaft "appears" to be 180 out of sync. I know that sounds funny. But it is really probably 360 degrees out of sync. There is a 720 degree (2 rotation) sync on that gear.
To understand better how to check it took me a little while to get a grasp on what was happening. Here are some important things to know.
Timing mark is at 9 o'clock.
The balance shaft makes 2 revolutions for every one crank rotation.
If this is off there will be a very slight but sharp vibration at 4k to 4.5k rpms.
I felt it after my belt swap but thought it was just new fluids or something. But it never went away. Then my starter failed. When changing it I noticed that my flywheel dust cover had split. Then my Alternator failed. The bolts vibrated out of it. My oil pan has had a problem with a slow oil leak which I thought was a bad gasket on my oil return line from the turbo. Then I shredded an accessory belt, then another...
So I started to do some research.. After speaking with others that have had balance shaft alignment issues it sounds like all the normal conditions for a balance shaft being 1 rotation off (180 out). So Next week I will be checking my balance shaft alignment.
How to check:
Timing mark on the block is 9 o'clock (remember)
Put the timing mark on the gear at 12 o'clock. Yes this is not where is should be to be in line. Now let go of the gear. It will fall either counter-clockwise, towards the timing mark on the block or it will fall clock-wise away from the timing mark on the block.
If it spins/falls/rotates toward the 9 o'clock mark = it is in phase and rotate it counter clockwise 90 degrees to the timing mark and you should be on the money.
If it spins/falls/rotates away the 9 o'clock mark = it is out of phase. Rotate it clockwise 270 degrees to the timing mark and you should be on the money.
To understand better how to check it took me a little while to get a grasp on what was happening. Here are some important things to know.
Timing mark is at 9 o'clock.
The balance shaft makes 2 revolutions for every one crank rotation.
If this is off there will be a very slight but sharp vibration at 4k to 4.5k rpms.
I felt it after my belt swap but thought it was just new fluids or something. But it never went away. Then my starter failed. When changing it I noticed that my flywheel dust cover had split. Then my Alternator failed. The bolts vibrated out of it. My oil pan has had a problem with a slow oil leak which I thought was a bad gasket on my oil return line from the turbo. Then I shredded an accessory belt, then another...
So I started to do some research.. After speaking with others that have had balance shaft alignment issues it sounds like all the normal conditions for a balance shaft being 1 rotation off (180 out). So Next week I will be checking my balance shaft alignment.
How to check:
Timing mark on the block is 9 o'clock (remember)
Put the timing mark on the gear at 12 o'clock. Yes this is not where is should be to be in line. Now let go of the gear. It will fall either counter-clockwise, towards the timing mark on the block or it will fall clock-wise away from the timing mark on the block.
If it spins/falls/rotates toward the 9 o'clock mark = it is in phase and rotate it counter clockwise 90 degrees to the timing mark and you should be on the money.
If it spins/falls/rotates away the 9 o'clock mark = it is out of phase. Rotate it clockwise 270 degrees to the timing mark and you should be on the money.
Thread Starter
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From: Lafayette, LA (Da Bayou)
Originally Posted by G-UNIT
Newb...
Correct me if I am wrong... but that is what this forum is for.
Cajun power is the man. I understood his write up better than the Mitsu manual. One question I have for all you Pros, What would happen if I placed too much tension on the timing belt and the bolt. I hear a little whining sound should I be concerned?
Originally Posted by WrX Kila
Cajun power is the man. I understood his write up better than the Mitsu manual. One question I have for all you Pros, What would happen if I placed too much tension on the timing belt and the bolt. I hear a little whining sound should I be concerned?
G-unit, you're a dip..... keep working hard at it, and you might be a tool some day.
Originally Posted by Cajun Power
If it spins/falls/rotates toward the 9 o'clock mark = it is in phase and rotate it counter clockwise 90 degrees to the timing mark and you should be on the money.
Are you referring to some kind of shaft "lag" that you correct .... since you've turned it to the 12 oC position (in order to test for the right phase?)
Sorry if I'm being thick on this, but I may give it a shot myself and I'm trying to get a clear understanding of everything.
BTW, thanks for the great write up!
If you're a Newb, I'm a PRE-newbial
.... since I've only done Exhaust, Cams/Gears, full exhaust with Ex Manifld, O2 housings, Hotside, IC, fuel pump, gauges, Engine Mngmt, wideband, yada yada... Yeah ... what were we thinkin' ....learning about our cars like that
Originally Posted by WrX Kila
Cajun power is the man. I understood his write up better than the Mitsu manual. One question I have for all you Pros, What would happen if I placed too much tension on the timing belt and the bolt. I hear a little whining sound should I be concerned?
Unless you bottom out the hydraulic autotensioner, or it's not making contact with the swingarm, you can not have any effect on the actual tension of the belt. "Setting the tension" actually has nothing to do with setting the tension.
All we are doing is setting the autotensioner to the proper point near the middle of it's range of motion so it has enough adjustability in both directions to cover all foreseeable operating conditions.
Cajun, this has me puzzled .... I get the part about rotating it to 12 oclock and letting it fall (one way or the other) but I don't understand the "rotate it 90 deg counter clockwise" if it IS in phase. Hasn't it already fallen to that position?
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From: Lafayette, LA (Da Bayou)
I HIGHLY suggest using the screw driver trick if this is your first time just to be safe! Pull the down pipe and you can get to the bolt from there. It is not easy but the BEST way to ensure that the shaft is in phase.
Not to dis' anyone, but I don't understand the problems/questions here with timing isssues. When you can see the timing marks, line them all up. Then remove the belts. Don't move the pulleys- yes, they might move a few degrees, but not 180+; if they move 180, you're doing something wrong. Install the belts and adj the tensioner protrusion. The tensioner is a PITA to get in the middle of spec, but other than that you should have no problems. You can hold the cams inline with two box end wrenches wire tied together. If you are removing pulleys to change oil seals then I can see things getting out of whack. But for just a belt change you should have no issues- just don't move things once lined up before removing the belts. If in doubt use the screwdriver check- it's easy and fail safe.
just to add to this because i had questions here are all the part numbers required including the auto tensioner and tensioner pullies...
03620-MR984778 Belt,balancer Timing
03616-MD352473 Tensioner,balance
03152-MD156604 Pulley,timing Belt
03110-MD326059 Belt,valve Timing
03178-MR984375 Adjuster,timing Belt
03158-MD369999 Pulley,timing Belt
03620-MR984778 Belt,balancer Timing
03616-MD352473 Tensioner,balance
03152-MD156604 Pulley,timing Belt
03110-MD326059 Belt,valve Timing
03178-MR984375 Adjuster,timing Belt
03158-MD369999 Pulley,timing Belt
