Timing pointer alignment?

[fsutim]

My manual shows how to do a timing pointer alignment, I did this and noticed that it was about 1 1/2 inches off to the left side. Is there any particular reason to allign the pointer?

 

[Dhadley]

Re: Timing pointer alignment?

Only if you are going to check the timing and then you will need to know where top dead center is. <br /><br />That's off a bunch. Thats way, way more than the length of the slot in the pointer. Something is not right. Tell us exactly how you did it.<br /><br />Good luck!

 

[Joe Reeves]

Re: Timing pointer alignment?

Error encountered here. Reply is posted below.

 

[R.Johnson]

Re: Timing pointer alignment?

If I am not mistaken! you turn the flywheel clockwise about an inch past top dead center. Put in the piston stop tool to contact piston, and mark flywheel at pointer. Then continue to turn flywheel until it contacts piston stop again, and mark at pointer. Locate center between marks, and remove stop tool. Aline center mark with pointer. If need be, move pointer from center line to top dead center. You do not move flywheel in oposite directions to make this adjustment.

 

[AUGIDAWG]

Re: Timing pointer alignment?

The way I did it:<br />The flywheel has marks every 1 degree.<br />Put the piston stop in cylinder #1.<br />Adjust the length of the stop to where it stops the flywheel somewhere between 10-20 degrees.<br />Make a mental note of how many degrees it reads according to the pointer, for example, say 12 degees BTDC.<br />Rotate the flywheel the opposite direction until it stops, take a mental note of how many degrees it reads according to the pointer, for example, say 16 degrees ATDC.<br />Subtract the difference and devide by 2. 16-12=4 devide 4 by 2 gives you 2 degrees.<br />Loosen the screws to the pointer, and move it 2 degrees.<br />Tighten the screws to the pointer.<br />Rotate the flywheel back and forth, and make sure you get the same reading, in this example, it would be 14 degrees BTDC, and 14 degrees ATDC.<br />You are done.

 

[Joe Reeves]

Re: Timing pointer alignment?

For what it's worth, here is a scanned page from the OMC service manual.<br /><br />TIMING POINTER ADJUSTMENT<br /><br />Engine Performance depends on the accuracy of ignition timing and carburetor synchronization. If major powerhead componenti have been replaced, or timing pointer disturbed, the pointer should be re-checked against the TDC mark on the flywheel. To check and adjust, proceed<br />as follows:<br /><br />1. Disconnect spark plug leads and remove spark plugs.<br /><br />2. Temporarily set timing pointer mid-way in its adjusting slot. Using Piston Stop Assembly (Special Tool #384887). Install tool in #1 cylinder spark plug hole. Turn flywheel clockwise until piston contacts end of tool.<br /><br />3. Mark a line on rim of flywheel opposite timing pointer. Now turn flywheel counter clockwise until piston contacts tool. Mark a line on rim of flywheel opposite pointer.<br /><br />4. Using a scale, measure the mid-point between the two lines. Mark the mid-point line on the rim of the flywheel. If the mid-point line and the cast-in TDC mark on the flywheel are in agreement, the timing pointer alignment is correct. If not, proceed to Step 5.<br /><br />5. Turn the flywheel to align the mid-point mark with pointer (LEAVE FLYWHEEL IN THAT POSITION. DO NOT MOVE FLYWHEEL BEYOND THAT POSITION). Loosen pointer adjustment screw and move pointer to align with cast-in TDC mark on flywheel.

 

[walleyehed]

Re: Timing pointer alignment?

I have to agree with R.Johnson on this because of the possibility of folding the waterpump blades over.<br /> It doesn't matter how far you go "slightly past" TDC, when you install the stop to the point it touches the piston, when you continue in the direction of rotation-coming up on TDCC #1, the rotation will stop exactly the same distance BTDC, as you started at ATDC, and you will never hurt the waterpump doing it.<br /> The OEM manual states DO NOT turn flywheel in oposite direction of rotation.....

 

[AUGIDAWG]

Re: Timing pointer alignment?

The only problem with the manual's method, is you have to remove the piston stop, then hope the flywheel doesn't turn, move the pointer.<br />Then what?<br />Put the piston stop back in, and check your work.<br /><br />My method you leave it in there, and there is no measurements. You use the factory hash marks.

 

[Hooty]

Re: Timing pointer alignment?

His flywheel may have degree marks for nr. 1 cylinder and nr. 2, not knowing which engine we're talking about.<br /><br />c/6<br />Hooty

 

[R.Johnson]

Re: Timing pointer alignment?

Augidawg! Thats why you turn the flywheel about an Inch past center, or the piston on the down stroke. You don't have to remove the stop tool. We'll have this guy so confused , he will never get it set. Put a pencil in no. 1 spark plug hole, turn flywheel until pencil won't come out any further, close enough. Jeez.

 

[AUGIDAWG]

Re: Timing pointer alignment?

How do you perform step 5 without removing the piston stop?<br /><br />If the manual says "do not rotate flywheel backwards", then how do you perform steps 2 and 3?<br /><br />If you put the piston stop into cylinder #1, then how could you posibly get confused with the timing marks for cylinder #2? There isn't enough movement in the slots that go to the pointer to get it that far out.<br /><br />I have come to the conclusion, that the manual is not perfect. There are errors. There are more than one way to skin a cat. If one way is easier, faster, and more accurate, then that way is better. Both ways could be the right way to do it, but one way could be "more right" then the other.

 

[Dhadley]

Re: Timing pointer alignment?

We use a "motorcycle timing gauge". Actually all it ammounts to is a dial indicator that screws into the spark plug hole. And it doesnt cost a whole lot more than the piston stop tool.

 

[AUGIDAWG]

Re: Timing pointer alignment?

I have used such a tool many times.<br />When I read in the Johnson manual about the piston stop method, I really liked it.<br /><br />The dial indicator is ok, but when the piston appraches top dead center, the ratio of degrees rotated to thousands of inches of piston movement, becomes null.<br />In other words, because of clearance in the top end bearings, bottom end bearings, main crankshaft bearings, the crank can rotate without any sign of piston movement.<br /><br />With the piston stop method, you are taking up all of the slop in all of the bearings, and the farthur from TDC you stop the piston, the more accurate the measurement becomes. Half way between TDC and BDC would actually be the best, but there are no timing hash marks that far away.

 

[Cricket Too]

Re: Timing pointer alignment?

I thought clockwise and counter clockwise were two diffewrent directions, so therefore the manual does say to turn the flywheel in two different directions and it seems like a perfectly clear explanation as to how to do it to me. The other teqniques seem logical also so I guess it's whatever works best for you as long as it gets the job done correctly.

 

[rodbolt]

Re: Timing pointer alignment?

hello<br /> I just use my dial indicator and mark .05" btdc and atdc and split the difference. take about 10 min and its close enugh. good luck and dont waste to much effort on one degree

 

[kenneths]

Re: Timing pointer alignment?

My only concern guys, was turning the waterpump backwards and folding the ears the wrong way.....Maybe not a usable, valid statement, but I have seen this happen (the results of) and the manual DOES state turning the flywheel BEYOND TDC, and continue in a clockwise direction after the first mark is made.......

 

[Walker]

Re: Timing pointer alignment?

It will not hurt the impellor to turn the flywheel backwards, that is unless your impellor is old and cracked already. As soon as you turn the flywheel clockwise, either by hand or by starter, the impellor wings will align themselves the right way.

 

[G DANE]

Re: Timing pointer alignment?

My Clymer manual 1991 has following suggestion:<br /><br />Turn motor clockwise to flywheelis around 1 1/2" past TDC mark. Insert piston stop tool. Mark pionters position on Flywheel, holding piston back against stoptool. Turn motor clockwise till piston touches stop tool again. Mark this position on flywheel too. Using a flexible scale, find exact center between marks. Turn motor to center mark is at pointer tip. Adjust pionter to tdc mark on flywheel. No turning counterclockwise with this method.

 

[AUGIDAWG]

Re: Timing pointer alignment?

That method is leaving out one thing.<br />In order to "Turn motor to center mark is at pointer tip.", you must remove the piston stop.<br /><br />Ok, that worked. But, how do you really know for sure unless you check it?<br />How do you check it?<br />Put the piston stop back in and repeat the measurement.<br /><br />Why measure when the marks are already there?

 

[kirkland]

Re: Timing pointer alignment?

My Clymer manual says the same thing that the DANE's does but what Dane didn't say is that you should center the pointer before starting above procedure.....think about it a minute it will make sense.....i just did this very thing two nights ago using this manual it worked out just fine...motor never turned CCW...not that i think it would hurt the impeller but in any event there is no CCW rotaion in this procedure. As the piston stop tool is inserted after piston is ATDC and marked there then moved CW to BTDC then marked again....remove tool.....measure and mark at half way between marks and mark again...this is TDC...I just realized you guys made me understand what i just wrote....if it hadn't been for this site i don't think i could have explained this or even understood it before....THANKS TO ALL THAT CONTRIBUTE TO THIS WONDERFULY HELPFUL SITE<br /><br />Jeff