Which engine coupler ?

[labzman3]

1985 Mercruiser 120 hp.
# A492171
Aplha outdrive

Which engine coupler came on this engine ? I believe mine is bad !
You should be able to see some splines when pearing up thru the gimbal bearing correct ? I am preparing to slide the motor forward, BUT want to make absolutely sure before I proceed !!!


Thanks all,,

 

[dubs283]

Re: Which engine coupler ?

don't slide the motor forward to inspect the engine coupler

pull the drive, inspect the splines on the driveshaft and look at the coupler with a flshlight

 

[labzman3]

Re: Which engine coupler ?

Dubs,,, have the OD sitting on workbench, splines look ok on driveshaft,, have cleaned and looked up into back of motor area,, and we cannot see any splines,, sooo ? When we put boat into gear out at the lake, it let out a loud "whine" sound and did not move. When we got home, hooked it up to muffs, put it into gear and NOTHING,,, motor revved up, but no prop movement and no water coming out of the motor,, We have checked the OD, by putting in gear and locking down the driveshaft, and trying to turn the prop,, just to see if we stripped a gear,, I have never changed the coupler since I have owned the boat 7 years, BUT want to make sure before I proceed ??????

 

[bigskiohio]

Re: Which engine coupler ?

Just look in there and see either rubber is gone or splines are gone .
easy fix just the labor might take a few hours or a weekend matters how hard you hit it , replace the water pump in drive now while on bench . without drive on you cant see drive shaft not turn. so get in there and look . Also check the drive by turning prop.

 

[pseank]

Re: Which engine coupler ?

All that sounds great, but be aware a rotted transom will cause your new expensive coupler to go bad also. I was told to stand on the outdrive while out of the water and see if the transom flexes. My 1983 Galaxy had a rotten transom. I removed the outdrive, removed the engine and seperated the housings from inside and outside the boat. Then I cut the fiberglass from inside the boat and dug out the old rotten transom. I used marine plywood as it has no gaps in it and epoxioed two 3/4" pieces together and clamped for 48 hrs. Sanded outer fiberglass from inside the boat until it was smooth. Cut to fit inside boat especially angling bottom to fit bottom of boat. epoxied new transom to inside of the boat and used angle iron inside and out with all thread to clamp through existing bolt holes for drive. After another 48 hrs I removed iron, cut out hole for drive using hull as template and fiberglassed inside back with heavy mat . painted spinnaker white and reassembled. Put a used coupler in and it ran great another 4 years until a submerged mammoth log sheared my outdrive off. Remember make sure your transom is not rotten and also have the engine aligned proffesionaly or buy the correct alignment tool or else you will need another coupler and or gimbal bearing.

 

[labzman3]

Re: Which engine coupler ?

Yes I have already stuck a new water pump in, other impellar was taking a "set", so put all new kit in. I think I will stick drive back in temp. and put in gear, and see if the driveshaft spins while engage in the coupling ?? I am also preparing to replace gimbal bearing, and all bellows and hoses while I am at it ! It hasn't been done since I have owned the boat, so guess it's about time. Anyone know WHICH coupler this takes, as it appears it could either be the tri -angler one or the smaller round one ? Looks like my boating is done for this year
1985 merc 120 hp # A492171

Thanks !!!!!

 

[bigskiohio]

Re: Which engine coupler ?

this is the one i used that is a tough year but once you puul engine you will know for sure.


http://www.shop.tungstenmarine.com/Engine-Coupler-for-Older-Mercruiser-Chevy-110-260HP-TM2171.htm

 

[labzman3]

Re: Which engine coupler ?

Thanks, Bigski,,, that is cheaper than all the other places I've checked out so far !! UPDATE !!! Put OD back in,, put in gear,, put prop on,,, and it turned with NO problem Had wife turn prop while I climbed in for a look,,, and WAY in the back I seen the driveshaft turning in the coupler ! Pulled OD off,,, keeping fingers crossed,,, stuck my finger in,, and felt only small ridges,, which I assume WAS my coupler!! Looking closer,, looks like I may have to pull motor completely out to get to this,, as the back edge is flush with the bellhousing/flywheel cover !!
NOW the really big ? is,,, do I make this my winter project or finish remodeling the foyer like I told wife I would do last year ??? DECISIONS/DECISIONS !!! Anyone have a quarter to flip ? LOL

Thanks,,,,,

 

[elkhunter338]

Re: Which engine coupler ?

Yes it sound like you spun the engine couple. I did the same thing a few years ago, I was 7 miles out in the ocean. 3.0L merc
I would highly recommend replace the coupler and drive shaft so you have new splines and coupler. My coupler was alum. but the splines still showed wear. Made sure you align and gease the new coupler, and check the transom for rott.

 

[labzman3]

Re: Which engine coupler ?

LOL,, guess I will not complain too much then !! I was only at the local lake !! I own the alignmet tool, so I am good there !! I have an older Starcraft,, and I can and have checked out the plywood bolted to the aluminum transom,, I am betting this was the orignal coupler,, I have been told that some are now steel rather than aluminum ? I have just been having trouble finding out which one is on my motor ?

later ,,,,

 

[elkhunter338]

Re: Which engine coupler ?

My old engine had the old coupler with alum splines, the new coupler I bought for the old engine was still alum. Then my cam gear broke about 20 hrs after the new coupler.
The new 2007 engine I put in has the triangle coupler with steel splines.
I think it depends on the flywheel. My old engine 2 piece rear main seal with the small coupler, the new engine is a 1 piece rear main with the triangle.
Pull the engine and look it will be obvious which one you need. Not a big job to pull the engine cause you do not have to remove it from the boat, slide it forward on the floor and you can change the coupler.

 

[paultjohnson]

Re: Which engine coupler ?

Arent all coupler splines/insert alum? They are somwhat - sacraficial ? To protect outdtive. If the splines and driveshaft were both steel, both parts would get trashed- steel on steel. Would have to replace both parts, Coupler serves somewhat the same function as a prop hub.Will give its life up 1st

 

[Fun Times]

Re: Which engine coupler ?

I have just been having trouble finding out which one is on is on my motor ?

Hi, I believe your answer to your question lies inside the link of that coupler that was posted for you earlier.

If you scroll down a bit, It should tell you if that engine coupler would fit on your engine or not by comparing the engine serial number range the website has provided.

Their web site says 120 HP Serial No's 1537370 - 6229717, Your serial number is (A492171) So according to that, That is not your engine coupler, It looks like you should have a "triangular" coupler, But that's one of those things you won't know till you have a look to be safe.

By the way according to mercruiser your engine is considered a 1986 MERCRUISER 120, Model No: 01202006 when looking up parts.

Here is your engine parts using your engine serial number range.
http://www.mercruiserparts.com/selectSerailRange.asp?doc_nbr=120+++++GM+153+I/L4++1983-1986

Good luck with it.

 

[labzman3]

Re: Which engine coupler ?

Thanks Boat Tech,, no I was not aware that it would classify as an 1986 !! I spent hours searching the web and could not pin it down to which one it had ! But like everyone said,, going to have to pull the motor forward to remove it,, so I would find out then !! Just was trying to plan ahead !! Got to go to work,,,,,

Thanks All,,,,,

 

[bigskiohio]

Re: Which engine coupler ?

could do it in a day if you wanted too. It matters on boat hull also if you have room. They use to sell the triangular coupler.

 

[labzman3]

Re: Which engine coupler ?

Bigski,, well I am not going to get into a hurry,, cause if I do,, I'll surely mess something up !! I am going to do the bellows and gimbal bearing while I am at it, since I have never replaced these items, and I have owned the boat for seven years now ! I see you are a fellow starcraft owner also !! I LOVE mine,, wife wants a bigger boat/cuddy,,but mine is paid for,,caused me very little trouble, and fits into my garage

Now here's a question for all you DIY'ers,, I have a feeling a regular engine hoist will not work, for my situation,, is that what most of you fella's used to move your motors ? I think my boat/trailer sits to high ?
Guess I'll have to find someone with a chain hoist !! I'll be ready to pull motor,, if I stay busy at it tomorrow night !!

Later,,,,,,

 

[farmer9009]

Re: Which engine coupler ?

When changing my coupler I used an engine hoist to lift it just above the bilge area and put a 1? piece of reinforced plywood under it that spanned the bilge area then sat the engine back down on the plywood. This was about as high as the engine hoist would lift but enough to get to the floor level where I could work on it. I had to change to a new style drive shaft when I changed my coupler.

 

[bigskiohio]

Re: Which engine coupler ?

i am still looking for a 21 ss ...... Take your time but you will see not as bad as you would think leave harness on engine and
front mount. look into new mount bushings i didnt but i am planning on full tear down soon. Mine has been troubl free too i have put less then $150.00 a year in it .

 

[elkhunter338]

Re: Which engine coupler ?

If you are very carful a good cumalong will work to lift the engine a few inches out of the bilge. I used a good chain hoist when I removed the engine from the boat. Those 120 are not that heavy. I think 300lbs ish was the shipping weight on my new motor.

 

[labzman3]

Re: Which engine coupler ?

Bigski,, the mount busing's you are talking about are in the rear of the motor correct ? Maybe I am figuring this wrong !! I was thinking of splitting it right at the housing covering the flywheel ? And from what I see,, I am going to have to take weight off motor,, then remove front motor mount/adjustment block,, then hopefully scooting motor forward,, and gaining enough room in back to remove coupler ? I think I will brace up back end of motor with blocking/plywood,, Hope I can find someone with a chainhiost and tripod. Well only 2 small items to disconnect now,, Let me know if I am going at this wrong way,, guys !!


Later,,