Starter motor questions

[hag]

Hi all, two questions about starter motors. (1992 merccruiser I/o serial # d805173).

1, when getting new one the best way to figure out CW or CCW rotation ? Difficult to understand which part is the direction referring to and which side your looking at it .

2, lubrications. Do you grease, oil or nothing to the starter shaft—the shaft bunion turns on. Opinions seem to differ.

Thanks

[Mumbles]

I’m not positive but I believe Mercury views their motors from the rear instead of the front as is normally done. In other words, what the rest of the world would say is a CW rotating motor, Mercury would call it CCW rotation.

You’ll have to double check but I’m sure this was the issue I had a few years ago when I rebuilt twin 470’s and had to get the correct starters for them. Both motors ended up being standard rotation with one of the outdrives being reverse rotation.

• This reply was modified 3 years, 8 months ago by Mumbles.

[hag]

Well I looked up the part number on marinengine.com using the mercruiser serial number, got starter 18-5911 Sierra…it says it’s cw rotation. I ordered few days ago and got part….but something in the back of my mind remembered cw or ccw rotation…started looking into it and got more confused and worried I got wrong part.

On the boat, looking aft to the pulley it turns cw , if I imagine myself at the back looking forward then it would spin ccw.

The starter sits low starboard side with the point/binion pointing aft.

I’ll take the old one out tomorrow and see but I think I screwed up and ordered wrong part..but marinengine.com part number was specific to my engine serial number…

[outbdnut2]

Looking at my Mercruiser shop manual for my 1996 4.3 Liter V6, They define engine rotation as looking at the engine from the stern end – that’s where the outdrive hooks to the flywheel, and the rotation of the V6 engine is counter-clockwise, as probably is all the other engines they use.

I also have the shop manual for the outdrive , and it shows reversing rotation is done by the the outdrive, so it doesn’t affect the starter or the engine. Note that the engine and the outdrive have separate serial numbers.

For starter Lubrication, you didn’t say which engine you have, but if it’s based on a general motors engine like my 4.3 liter is, it’s probably the same. My shop manual says that if you disassemble the starter, internal bearings and internal gear teeth (yes there are some gears inside you can’t see) should be lubricated with Quicksilver 2-4-C Marine Lubricant. There is no required maintenance regarding this, so unless you have disassembled the starter, don’t worry about it. It’s like a car starter and you don’t periodically lube them. The shaft end that sticks out has the “Starter Drive” on it.. This is the gear that rises up to engage the flywheel and there is a ratcheting mechanism right behind that gear that is part of the starter drive assembly. If your starter spins but doesn’t turn the engine, the ratchet is shot (a common failure) so that starter drive assembly is all you need to replace – take the old one, or your whole starter to any auto parts store and they will have it, and it will look similar to the one in the link below: The manual says to lubricate the starter shaft that this slides on with 10W oil when you put on a new starter drive. My personal experience with cars is lube that shaft very sparingly because excess oil attracts dirt and that will cause problems.

If you have a MerCruiser with a Ford-based engine, recommended lubrication may be different, but I don’t think Mercury has used Ford-based engines since the 1970s.
link to Typical starter drive below.
Dave

https://www.napaonline.com/en/p/BK_6561117?partTypeName=Starter+Drive&keywordInput=starter+drive

• This reply was modified 3 years, 8 months ago by outbdnut2.

[outbdnut2]

I looked up the Sierra starter you bought and yes – it’s definitely a GM starter, so the stuff I just posted applies.
Dave

[hag]

Thanks Dave. I just found this post with pictures…it helps… I think I got the right starter.

https://forums.iboats.com/filedata/fetch?id=7011288

[outbdnut2]

hag wrote:

Thanks Dave. I just found this post with pictures…it helps… I think I got the right starter.

https://forums.iboats.com/filedata/fetch?id=7011288

Interesting. It does say “Inboard engines” onthe diagram you found, which makes sense that there would be reverse rotation engines for dual prop setups on inboards with shaft-driven props under the boat, not on an outdrive. Now maybe some V8 Merc I’Os do have reverse rotating engines, but with the V6 I have with the Alpha One outdrive, the shop manuals say reverse rotation is done in the outdrive.
Dave

[hag]

i used picture to follow the rotations: the starter rotates clockwise (CW)-looking head onto binion. since it faces aft, will turn flywheel CCW which in turn will turn pulley CW when facing it from the front looking aft. And that is the correct direction. you follow? at least i think i follow…ill see tomorrow.

[outbdnut2]

hag wrote:

i used picture to follow the rotations: the starter rotates clockwise (CW)-looking head onto binion. since it faces aft, will turn flywheel CCW which in turn will turn pulley CW when facing it from the front looking aft. And that is the correct direction. you follow? at least i think i follow…ill see tomorrow.

It sounds like you have a good handle on it now! Hope the starter cures your problem! Just curious as to what engine you have? HP? V8?
Dave

[hag]

ya i’ll see who has a handle on who… also not looking forward to taking it off and putting new one on…heavy and in tight position..we’ll see…it almost left me stranded on the lake …starter spinning but not engaging…a couple of whacks on it got it to engage and started to go home.

I used that picture to only figure out if it is the right starter turning engine in the correct direction…not think about the outdrive that you were talking about.

its a 1992 mercruiser alpha one 3.0L, serial # d805173. not sure but i think 150hp.

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