TOPIC: Setting timing / carbs for 63 Merc 650

Does anyone have a good method to set up the motor. Tried method from manual but it is written for someone who has already done it. I found TDC without too much problem but a "link and sync" video that seemed to make a lot of sense didn't work at all. I think because I have mag ignition. Don't have a buzz box. Not sure how that is supposed to work. Do have a timing light but the motor really doesn't have any markings that can be identified.

Have you cleaned and set the points at 0.010" on the magneto.

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Did you have the plate off the distributor to find the timing mark to line up the belt ?

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You can easily use a magic marker to put your own timing mark on the flywheel.---I do have a 63 --650 and it is a nice motor, some other old 650's as well.

Yes. set points to .008 Should I go to .010? lined up mark on flywheel to timing pulley. idles great. trying to figure out max advance.

I aolso have 2 '65/650's but never had to reset timing on the Merc's? Yes, points .010 in Service Manual and +.000 -002. so thinking a snug .010 would be perfect, dwell is 48 deg. in the Manual. If you didn't remove the mag/ dist why mess with the timing? If I rebuild a porsche or corvair motor I set the points dead on first then the timing then usually never mess with timing again.

On the carbs, its been a long time but think I sync'd them with a Venturi meter or not sure its name, (think theres enough room in front of bottom carb?) holding it over carb inlet back and forth between both carbs till the red ball is the same on both. Needs linkage to be pulled to fast idle off the idle stops so butter fly is slightly open for a good setting. All disclaimers apply

Professor I like the '63/650's also, its thinner cowl looks better imo and dont mind the external cables

I do have copies of the timing degree plate Thom sent me if needed. Could print it can cut out. Need a email though if ya want it. wmgeee (at) aol dot you know.

The start to my problem was that I spun the original 13p prop that I had been using for the last bunch of years. Before the tubing event I could pull up slalom and was pretty happy with everything. When I put on another 13p prop the motor performance was horrible. Since I had never set up the motor properly I figured it was time to make sure all was well. I wish I could go back to my original setup but that ship has sunk. Now it just drags me around until I hurt.

Eric I sent all i had. theres some pics showing how to make a needle pointer thing for the chart. imo, U should have the '65 and prior service manual if you going to keep merc's in your stable. Bill

CRASH! into the thread I am....

So when syncing the carbs, I assume the idea is to have them all pulling as much the same amount of air as possible, and not so much (if at all) about air/fuel mix. Assuming I am correct about that, what on the carb do you adjust?

the link between the 2 carbs and the pickup on the top carb.

think the "new" prop could be the issue? before I go threw all the hassle of the synk&link I would look at the only change you made before the "dragging " started, just because the prop Say's its the same dont make it so......

I know the new prop is the "problem". BUT the old one is spun. Can't pull a tube or skier with it. I never had the motor set "right". It just worked well. It might have more power in reserve if I get it set "right". I think it is running too rich too.
A 65 hp motor on 14 ft light boat should pop a skier up. (boat is 315 lbs, motor is 215, I am now 205)

Maybe your expecting too much from 65hp. On mine I have to use a 15p for water sking and 19p for cruising up to just over 40mph max with the g3. the 15p would get to around 32-36mph i think with excellent hole shots? but still had to leave slack in tow rope and push and pull a bit if skier is in the 180+lb. range with one in the boat using double skis. A dead pull is hard getting up with single ski. lots depends on elevation. Single ski off the beach imo...
Your car might have lots of power but try and pull a small tree stump out of the ground, tires will most likely spin just like a prop will. Single ski off the beach imo...

using a 13p prop. don't care about top end. just so it is fast enough to ski. best has been the 13p bronze with 2 blade. tried 15p 3 blade no good. and now 13p 4 blade. it should be as good in my opinion with the hole shot as the original 13p.

if your old prop works so well and is just a spun hub.. why not have it rebuilt.. new hub installed.. and yes just because it says its the same pitch it may not be..

You say you dont care about speed but thats what lets us know whats going on plus RPM at a certain speed. Try this out, ; www.go-fast.com/Prop_Slip_Calculator.htm gear ratio is (2) i think and use 5200 for rpm. Dont understand using a 13p on that boat being so small and light? you shouldn't get over 30mph max with a 13p and you risk over reving if you dont use a tach? A 15p is like driving a truck in low gear and also easy to over rev with. If both your props are old they both may be slipping. I'd take them to a shop and get them tested for slip and pitch as they may have changed the pitch at some point? Or just buy a new one, Some shops will loan ya a prop to try out before buying? You will never know if theres an issue with the motor if ya have a crappy prop I think a 15p should get you 33-36mph at or near 5000-5200rpm with real good hole shots?

the 15p and 13p 4 blade are modern props and not slipping. I have a tach I want to use for it but haven't figured out the right setting yet. Don't have a way to confirm when I do think it is right. I went a similar link and that was why I originally bought the 15p. But it didn't help so I kept running the 2 blade 13p.

Hi,
I e-mailed you directly, but it may have went to the Junk file. If the new props are Mercury produced, the 15" will act much as an original 17", and the 13" like an original 15". Adding vent holes would be quite helpful though. Ideally, a reduction of diameter (as with the original propellers, versus the original 6-cylinder propellers) would also be best.

Regards,
Joe
www.fergusonpoolemarine.com
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Joe,
I had an obsolete email in my profile so I didn't get your email. I have now fixed that.
Thanks

I think Joe has nailed it as ever. The 650 had the large gearcase with the 15 spline props BUT the diameter of the props was smaller for the 650. So as Joe rightly says it will act as a taller pitch prop would. I had an original 17p prop on my 650 but it got chewed up so I fitted another 17p without knowing about the reduced dia, & as Tomahawk said it ran horrible. In the end I replaced the 17p ali Merc original with a later (large dia)14p s/steel cupped Merc prop (got it cheap) & it still pulls less revs than the original 17 did (it did rev a little high before). That diameter (+ cupping if it has it) makes a HUGE difference to these motors.