Starter Question

Ok guys.. time to put on your thinking caps. Here's my problem. I have a 9.8 Mercury engine. Serial number A901218 long shaft, electric start brown stripe on the cowling. I got the serial number off both the plug on the top of the block and also off the plate on the swivel. Also, the block has the word "Lightning" molded into it on the Starboard side. It's a 2 cylinder, 2 stroke engine. I'll post pics tomorrow.

Anyways, here's my problem. As far as I've been able to determine, the engine is a 1984. The electric starter for that year was a 78011, also known as a 50-78011. It's "obsolete" and I'll be damned if I can find one anywhere. The PO of this engine must have had the same problem because there's a different starter on the engine, but it doesn't seem to have enough "oomph" to turn the engine over. (I can use the recoil starter and the engine turns freely and starts after a few pulls).

So,
1st... can anyone tell me exactly what year the engine is? I cannot find a listing for anything even close to that serial number.
2nd... is there a different starter that supersedes the 50-78011 or can effectively replace it ?
 
Thanks for the responses guys. :party:

my BET is that the one on it just needs rebuilt

All things are possible, but the end caps are good, the brushes look almost new, I cleaned the commutator, and oiled the bearings. Everything seems to check out ok. Unfortunately, the starter had it's part numbers painted on with white paint over the black surface, and over time the part number has become illegible, so I don't really know what the starter is and so can't find out it's specs.

THEFERMANATOR said:
The best I could find was somebody parting one out for you. http://tampabay.ebayclassifieds.com/...l/?ad=15584050 It looks like the ARCO 5367 MAY work, but I can't find a cross reference back but to 86 for it.

I came to the same conclusion on the Arco unit. It looks a lot like the one on the engine now. But the engine has two different mounting options.. If can mount a starter through side holes or through top holes. And the one that's on it now mounts through side holes, but that leaves a gap of about a half inch at the top of the starter where it goes up to engage the ring gear. It engages fine, just looks funny/wrong. That's what's lead me to believe this is not the original starter for the engine.

Thanks for the link to that guy parting out those engines. I sent him an email asking on prices etc. If you look carefully at the one pic, where it shows an electric starter on the left side of the pile, that's the style that I have right now on my engine.
 
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check the voltage at the starter positive terminal to the starter housing while trying to crank vs battery voltage while trying to crank to rule out high resistance connections
 
check the voltage at the starter positive terminal to the starter housing while trying to crank vs battery voltage while trying to crank to rule out high resistance connections

I ran a line directly from a fully charged battery directly to the starter positive terminal and another one directly to the ground. Same result as when run the normal way. Starter engages, spins up but just can't seem to turn the flywheel. If I pull the manual starter cord to give it some help it will spin the engine rapidly for several revs, but eventually it will lose speed and stop again.
 
Pics as promised:

ENGINE
98Merc001_zps10360d18.jpg


Cowl removed, starboard side, showing "lightning" on the block, starter removed
98Merc005_zpsc8c962e5.jpg


Serial number on plug
98Merc007_zps51447e11.jpg


Serial number on tilt/swivel
98Merc009_zps537f891b.jpg


Starter, front side
98Merc010_zpsbdc91642.jpg


Starter, back side, showing faded numbers
98Merc012_zpsce46f13b.jpg


Top mounting holes (Note worn paint showing something must have been mounted here at one time)
98Merc013_zps158e8df5.jpg


Side mounting holes
98Merc014_zpsf46bb1e2.jpg


Gap when present starter is mounted. Just doesn't look right
98Merc016_zps24b9dab8.jpg


Even with the gap, the starter does function correctly, meaning the throw of the starter gear to the ring gear is the correct distance, and the number of teeth (10) and the rotation (CCW) are all correct. No damage to the ring gear is occurring.
 
just so we don't assume anything... when you went through it you DID make sure the brushes moved freely in their slides and that there was no side play in the bearings?

BTW THANKS for the pics... I would LOVE to make my kicker e-start and was wondering what all was different.
 
just so we don't assume anything... when you went through it you DID make sure the brushes moved freely in their slides and that there was no side play in the bearings?

BTW THANKS for the pics... I would LOVE to make my kicker e-start and was wondering what all was different.

Happy to help on the pics. Not alot really different. My guess is the pull starter might need to be changed, (there are several of them for sale on eBay) and if your flywheel doesn't have gear teeth you'll need a different flywheel and some kind of starter button/switch installed. if you look at pic two (the one with the cowl off, you see that red button. That's the stop button... next to it on the left is the starter button. You can only access it with the shift lever in neutral, which is why it has that weird cutout in it.

As to the brushes, yes, they are free in their slides and the bearings are good, no obvious wear, and the rotor spins freely in them without any obvious side to side motion.

I bought the starter that Ferm found and posted in this thread, along with the entire lower leg. Mine is starting to show corrosion, and his looks much better (he sent me additional pics). (THANK YOU FERM)!!! So we'll see where this goes in a few days. It's being shipped 3 day fed ex, so I should get it by this weekend and I'll know by then what the score is.
 
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