TOPIC: '63 Merc 350 Starter Issue

First of all let me tell you what kind of whiskey was Carl's engineer drinking too much of when he designed this 2 cyl model Merc? The only way to R&R the starting motor is to pull the powerhead because the top cast mounting bracket does not separate like the later years and there is no room to lower it remove it.

I believe it is a 63 or 64 Merc 350.... 2 cyl 35 hp short shaft.

In any case....I have been waking it up and had to replace a coil and new points/condendors etc and managed to get good spark.

Then...the old starter would not turn it over fast enough. I then pulled the p'head and removed the starter. It was a bit dirty inside but the brushes looked good and I cleaned everything up really well and put it back together. Threw the p'head back on and cranked it over. It was still starting out cranking slow but would speed up a bit and enough to actually get the motor running. Stopped it but it was cranking really slow.

BTW...tried two different fully charged starting batteries so that is not the issue(used them to crank a 50 blue stripe I am also working on and it was no issue.

I have not taken it to a starter shop to try and get it load tested (non of the auto chains will touch it)....but it seems to be fine when bench testing with no load.

QUESTION..... When I removed the flywheel and the mag plate to replace the coils, points etc could I have reinstalled something incorrectly which would be dragging on the crank too much? Like flywheel not seated correctly on the shaft(key was not broken...too much torque on flywheel nut?) or maybe something else?

It has great compression but the starter should be able to crank it much better?

I see a guy about 1.5 hours away selling 3 350's for $250(one bad cyl, one tiller, and one long shaft)....none guaranteed to run. Maybe I should just grab them and maybe get a good starter and make another one run from the 3?

Thoughts or some kind of test I can try with my limited resources(multi-meter)?

Thanks,
Tim

I would buy the other motors. As far as the one you have I would ck the ground wires, even add on on a starter bolt, remove the spark plug wires and see if it changes things, if the timing is too far advanced it could do this, does it get hot? I had a merc that had corroded pos battery wire, it was green for several inches but the insulation wasn't bubbled or anything......its a merc and their picky . GOOD Luck

Have you tried jumping directly to the starter motor with known good cables? If you're using the original Mercury wiring harness, they are noted for losing much of their conductivity due to corrosion and wire deterioration. Sounds like you've eliminated the battery as a cause. Eliminate all other avenues before replacing the starter motor.

Hey Tim, I jsut got a 64? 35 over the winter if you end up with a spare wrap I could use one, was on a boat exposed to the eliments for at least 15 years, cleaned the points and it fired right up great compression. But it needs a wrap. Electrical... Dunno just used the pull start on it so far.. figure all the electrical is shot, Messed around trying to get the started off and decided it wasnt worth the time as it fired right up first pull.. Ok no help here I know but if you end up with a wrap let me know

Scott... what should have been the obvious thing for me to try (jumping the starter when on the powerhead) I did not do...too busy with other issues I guess. Anyways... I just put the powerhead back on again and hooked it all up. Same slow laboring crank with the controls. Jumped the starter directly(which isn't easy getting at that positive bolt buried down beside the cowl and whirrrrr...cranking like crazy.

Now I need to find the real problem. Grounds seem fine. I am wondering if it might be the solenoid? I have a couple of other old ones around here with that integrated mounting bracket onto the starter (no idea if they are any good but its worth a try I guess?).

I did butt slice two new battery cables into the wiring harness when I first got it as the wires were rotted bad and I cut back to clean wire.

Any thoughts on checking voltage with the multi-meter would be appreciated.

One thing I will have to do is pull the lower unit as I noticed I now have the shift shaft turned wrong as I moved it when it got caught up pulling the head....but that's ok as I need to replace the impeller anyways even though it was pumping.

Stash... I do have an extra cowl wrap from the parts motor I have used parts from. Not sure how good it is and will of course use the best of the two myself but will provide some pics after I do.
I may even pick up the three 35's I mentioned and will for sure have one for you if I do.

Tim

Tim Sounds like good progress there, Just let me know if you end up with one.

If I recall correctly, Merc actually replaced - for free - all the coils in this series of 35hp twins & there should be a Service Bulletin supporting this claim. Obviously it is too late to score a set of 'free-bee' coils, but purchasing a set of new coils will most likely eliminate the spark issue.

On your starter issue, I think Scott (C-Walker) is heading you down the right path.
Rather than dinking with the original internally compromised (+) & (-) cables, simply add a new set of (+) & (-) cables going between the battery & the powerhead. Do NOT disconnect the crusty originals - they will still be adequate in supplying voltage to the components.
Run the (+) positive cable from the battery directly to the primary large terminal on the starter solenoid.
Run the (-) negative cable from the battery directly to a powerhead ground (like the terminal used by the original (-) near the top of the starter).
I usually drill (2) holes in the front of the lower pan, install gromlets, and send the new (+) & (-) cables through this point,...BUT,..If you are a 'die-hard' original sort of guy,...You can probably sneek the added (+) & (-) calbes in the holes for the shift & throttle cables - thereby avoiding drilling holes in your pan.
Depending on how long of a run it is from the Merc to the battery, will identify which size cable to use for the newby (+) & (-) cables.
T

From a newby to forum, jumping in. I have two wrappers you're welcome to, but not collector grade at all. Both 7+1/4 inch tall, one SS corregated. one galvanized w/ 3 blk painted stripes,very rough paint. P.S. different Subject; I could not find "dull aluminum lacquer spray paint" for long time, but it's avail @ an air plane parts supply house. just ordered some. thanks for much good info , appreciate this forum. jim

After some further voltage testing etc. I determined that it was the old tired starter(magnets seemed very week when I had it apart). So off comes the powerhead yet again....sure am getting good at this.
I had another starter(that I rebuilt with new brushes) from I believe a bit younger 40-50 which basically bolted in but there were two issues. First issue was it did not have the tapped holes in the housing to mount the solenoid to. I solved it with a large wire clamp with a couple of 1/4x20 bolts mounted thru 2 holes I put in it. Next problem was that the starter was longer and the positive terminal was resting right against the internal wiring harness outer metals holding bracket. This of course would have caused major spark/short one I tried to start. So using dremmel cutting too I cut off diagonally one corner of the harness bracket and took off about 1/4 inch of the positive post on starter that now created a separation.

Everything back together....cranking as it should. Internal harness pin for the electronic choke solenoid is broken off so I am going to graft into the external harness close to the motor and run a new wire thru cowl directly to the terminal to connect to solenoid wire...easy fix.

She fired right up but now some more fun begins. It was pumping water fine but it was not running right. I R&R'd the carb so I think I can rule that out. Its racing then missing at idle and is all over the place. Gotta be synch and timing issue.
I'll start a new thread on that.

Thanks everyone for the help on this one.
I'll get back to you on the wrap Stash