MC 165 Inline 6 timing

Sangster21

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I have just installed a fresh rebuild 250cu in inline 6 into my boat. Rebuilt the carb while I was at it. Got it started without much difficulty - ta dah - hooray for me! Now I need to set the ignition timing. The timing marker has notches, but I can not see where the "0" mark is. There is supposed to be a 0 mark on it with 2 degree increments per notch. A bit tough to time it if I don't have a 0 reference. Any suggestions? I may take some sandpaper try to raise up some markings on the fresh paint. According to mercruiser manual there should be an "A" on the advance side and a "0" mark, can't find either. Drat.
Thank you,
Alantiming mark.jpg
 

alldodge

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Re: MC 165 Inline 6 timing

I would try sanding first to see if something shows up. I've been trying to get into other areas but there are issues on the web right now, will continue to look. My thought is the first point on the left should be zero. All the others going to the right should increase by 2, with the engine rotating to the left (counter clockwise) facing the front of the engine.
 

alldodge

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Re: MC 165 Inline 6 timing

According to manual number 3 your timing marks should not look like what you have. They should be straight and have no points which extend out. It does show the first mark from the right past the edge would be zero and are divided up in amounts of 2 degrees each.
 

Fishermark

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Re: MC 165 Inline 6 timing

Here's a pic I did of mine a few years ago. I notice you do not have the big "V" - but the numbers / degrees are to the left to advance the timing. Here ya go:

timingmarkson165straightsixcropped.jpg
 
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Fishermark

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Re: MC 165 Inline 6 timing

Just as a follow up - I believe your timing should be set at 6 degrees before top dead center (BTDC) with rpm between 500 - 550.
 

alldodge

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Re: MC 165 Inline 6 timing

Here's a pic I did of mine a few years ago. I notice you do not have the big "V" - but the numbers / degrees are to the left to advance the timing. Here ya go:

timingmarkson165straightsixcropped.jpg

Even the Merc manual is wrong every once in a while, thanks much
 

Sangster21

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Re: MC 165 Inline 6 timing

timing marks sanded.jpgI have gone back and done some sanding and I think I can just make out a 0 and a 12 mark, so I hope I will be good to go. Pic attached. I can make out a 12 fairly clearly and counting back by 2 degrees gets to what could be seen as a fuzzy 0. Thanks for help so far!
Alan
 

alldodge

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Re: MC 165 Inline 6 timing

Old guy and bad eyes to boot but I make out the 12, 8 fairly well, the 6 could be a stretch but the 0 works. Looks like you have your numbers. 4 degree high marks and 2 each on the lowers
 
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