TDC Dial Indicater Link & Sync 1989 100 HP Mariner

w2much

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Am I having brain blockage?I am going about the link and sync procedures as per my manual and am having trouble with the instructions. Here are instructions per SELOC Manual.: Timing Pointer Adjustment: Remove all spark plugs. Install a dial indicator in the No . 1 (top) spark plug opening. ( Done, no problem). Rotate the flywheel CLOCKWISE until the No. 1 piston is at TDC. ( Again done, no problem . I might add that at this point my timing pointer also indicates zero degrees, aligning with 0 mark on the flywheel) At this point set the dial indicator to 0 degrees. Rotate flywheel COUNTERCLOCKWISE until the dial indicator needle reads .600 " BTDC, then rotate the flywheel CLOCKWISE intil the dial indicator reads exactly .554" BTDC .( Can not do this as my dial indictor only has 5 mm of travel) If necessary , loosen the attaching screws and shift the timing pointer, until the.554" mark on the timing decal is aligned with the groove in the timing pointer as shown. Tighten the pointer attaching screws .......ect........ ----OK so my dial indicator only has 5mm of travel. Once my TDC is determined with the dial indictor and the Timing Pointer aligns with the 0 degree mark can I then time the engine. It seems to me that this procedure is just a double check on the timing marks on the flywheel. Appreciate your imput as I scraatch my head.
 

Don S

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

You are going to need a different dial indicator. The reason for the steps is when the piston is on TDC, there is a little movement of the crankshaft fwd and back that will not move the dial indicator needle. That is why you move it one way, then to second mark (without passing it and backing up). If you do go past the second mark, start over at the .600 mark
 

w2much

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

Thank You for your reply Don. Can the engine be timed assuming the degree mark is accurate. At TDC I have about .01 mm of play(almost nothing). Can I just aim the timing light at the proper degree mark ( according to the manual) and perhaps just retard the timing a degree or so rather than risk the timing being to far advanced ?
 

JUSTINTIME

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

some have movable timing indicators

best is draw 1 line on TDC
 

Don S

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

All Mercs that size have adjustable timing indicators. That is the reason for the procedure to LOCATE #1 TDC.
You don't just "Draw" a line unless you know where it's supposed to be. Once you know that, you just set your pointer. Of course, that process takes a dial indicator and a manual to get it right.
 

Laddies

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

2 much ck the end of your indicator and see if it unscrews most do and you can replace the end with a extension or even a machine screw to get the indicator on it's range
 

JUSTINTIME

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

u do not need a dial indicator
a piston stop, good flexible ruler and learn how to index the flywheel will work also
 

w2much

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

Thanks Again Gentlemen, Its geting late but here is where I ended up. For now I gave up on the timing due to the dial indicator . I will in the future attempt the machine screw idea(great idea by the way). I tried to time it but my timing light was uncooperative, do I need a special one for a two cycle? She runs great, I started her up. I was having a few other problems also. My tach was dancing around and my voltmeter is not working. I took out the rectifier to test( came up bad, I' ll puchase another one). When doing so I noticed the tach wire was not hooked up to the rectifier. Hooked it up and the tach works fine now. So I started out today to fix three problems and solved two. I'm OK with those results. Perhaps next week I'll try the timing again. My new question is , Does a regular car timing light work on two stroke outboards or do I need stronger glasses? Thank You Again.
 

JUSTINTIME

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Re: TDC Dial Indicater Link & Sync 1989 100 HP Mariner

t-light is a t-light
i use and inductive one, not the one u need to hook up to a 12v battery
 
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