1975 Mercury 1150 (distributor) linc and sync questions

[Stadacona]

Hi All,

I'm sorry if this has been covered before but I want to be sure I'm doing this right. I am following Clem's guide however I have questions about my timing marks. See the pics. I am trying to decipher the marks. I assume the two heavy vertical lines beside TDC are the first "timing event"? Then the next two bars to the left would be "timing event 2"? Then the final bar would be "max spark advance" point?

Also, in the other pic you can see the adjustment stops on the distributor. The lower left one is the idle stop...and the upper right one I assume is one I can adjust for "Timing event #1"? I also know the throttle stop and max spark advance are on the front face and I assume the max spak advance is what get set for "timing event #2"?

I removed and cleaned the carbs, changed impeller and adjusted the idle to 800 in neutral. It ticks along nicely and runs beautifully at full throttle...about 5200RPM and 44 MPH on my 16' Sidewinder with a 21P Aluminum prop. Seems about right.

When I did a time light at full WOT the timing at the pointer was only sitting above the "i" in the word piston on the decal. That didn't seem right, as I assumed it should be at the "single heavy bar to the left"?

Any guidance would be appreciated. She sounds great but as some have said they sound great right before you burn up a piston!

thanks!

 

[Laddies]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

First it looks like the flywheel has been removed from the hub, so remove #1 plug and make sure the marks and TDC are indexed properly then set your max spark on number one just 3 to 5 degrees less than max on the flywheel mark to compensate for today's crappy gas.

 

[Stadacona]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

I did test TDC with a caliper and it appears that TDC was right between the two marks to the left of the letters "TDC". Maybe this is too obvious a question but its about the marks - is TDC set at the (from right to left) first two vertical bars, then "timing event 1" at the next two vertical bars and then "max spark advance at the final vertical bar (or 3-5 degrees before it) assuming that TDC is correct?

 

[Stadacona]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

Quick Update

I just want to confirm that I just timed at idle and the timing light shows approx 3-4 tickmarks to the left (BTDC?) of the TDC mark...I assume this is where I set the first timing event..making sure that the dissy arm is touching the carb lever? That would mean then that the max spark advance would happen at 21 tickmarks from TDC? If that is the case then 21 ticks from TDC would just about take me to the two vertical lines on the left...does that make sense?

 

[Laddies]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

Thats right,

 

[Stadacona]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

Thanks! Will go try now.

 

[Stadacona]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

First, thanks for the reply, it helped me move along in a big way! Well, i followed the linc and sync and got it pretty much lined up as suggested, took her out on the water and she idled nicely, leapt quickly out of the hole and ran like a top up to 45mph (speedo) at about 5100RPM.....everything seems great, no missing, good response. Anything I should check for after? Like spark plug condition after x hours? Im a little paranoid as its running great and seems a little too good to be true I also burned out my failing solenoid switch cranking motor so need to get a new one of those now.

 

[Gomer50]

Re: 1975 Mercury 1150 (distributor) linc and sync questions

The three vertical lines to the left are 21 degrees BTDC,23 degree's BTDC,and 27 degree's BTDC.The 2 right after TDC are probably 2 and 4 degree's BTDC.