Timming ? on 1983 Chrysler 85hp

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hunt-fish-camp

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Mar 22, 2010
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My first post to this awesome site is a question about timing marks on a 1983 Chrysler 85hp. The flywheel does not have any marks only a number 10 stamped in it which does line up the the timing mark on the bracket when I check with the timing light. I am assuming the top cylinder is #1. If I put the cylinder at tdc can I make a mark on the flywheel and use that? Also when I was moving distributer it didn't seem to run better or worse, the idle would just go up or down. Is that normal? Also I just rebuilt the carbs and have them set at about 1 1/4 turn out and seems to run good. Is that to lean? I see other posts about running to lean and bad timing will burn a piston which I am trying to avoid. Sometimes when I turn the key to start I get a exhaust pop. Any info would be great. Kids are looking forward to a better boating season than last year.
 
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foodfisher

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Feb 18, 2009
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Re: Timming ? on 1983 Chrysler 85hp

A year ago I came here totally ignorant of outboard motors. The sages here gave me that advice. I bit the bullet and bought an OEM manual ($95).Using that manual, my questions became fewer and more pointed. Like a fog lifting, the ignorance dissipated. I now have a motor that starts with the click of the key and runs faster than I'm comfortable with. I was just paying it forward. You're welcome. I don't understand the wife reference. Could you please explain that?
 
Frank Acampora

Frank Acampora

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Jan 19, 2007
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12,004
Re: Timming ? on 1983 Chrysler 85hp

But while you are waiting for the manual you have no doubt ordered:

Older models of that flywheel were stamped with a 0 and a line for TDC and a separate line for 36 deg. BTDC. These were stamped in the top of the ring gear. If you have this flywheel, you may be mistaking the 0 mark for 10. Note that the TDC mark may or may not line up with the block pointer at idle and certainly not at full throttle.

newer models had a decal affixed to the top of the ring gear. If this is missing, you will need to determine TDC. The factory method is to set the piston at 36 BTDC. This is because with the piston at top dead center, the crank can still be a couple of degrees off TDC.

However, if you do not have the tool, then you are limited to setting the piston at TDC. If you do it very carefully and "rock" a couple of degrees to either side, you can feel TDC--but it takes a delicate touch and patience.

Once you have determined TDC, mark the flywheel. Now count the teeth in the ring gear--do it twice. (96? I forget.) Divide 360 by the number of teeth and you will find out how man degrees one tooth equals. Now simply count back the number of teeth that adds to 30 if you want to be safe, use 28.

Originally Chryslers were timed at 32 BTDC but in the 1980s they changed to 30 to compensate for poor quality marina fuel.
 
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