1978 OMC 120 / 400 Stringer Tilt Motor replacement

[KaGee]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

You can remove the clutch pak, after the tilt gear is off, without removing the shaft with the hammerblow on it. The clutch pack will slide out of the big bronze ring gear.<br /><br />*** DO NOT ATTEMPT TO DISASSEMBLE THE CLUTCH PAK ***<br /><br />Just clean it up. That tilt gear box needs a reseal job.

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

OK, I won't disassembly the clutch pack. I will soak it in motor oil as the manual states.<br /><br />However, do you have any idea if there's something blocking the gear from coming off of the shaft? This is the part that is puzzling me the most.<br /><br />Also, is the the clutch housing (the big bronze gear) supposed tomore rather freely when the motor is removed?<br /><br />I feel like I'm running into some serious stickiness here.<br /><br />Thanks,<br />Matt

 

[KaGee]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

A snap ring is all that holds the outer gear in place. IF you have removed the snap ring, then you have to use some PB BLASTER, heat and a little friendly persuasion to get it off.<br /><br />Make sure when you reinstall the gear to apply marine grease to the splines.

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

PB Blaster??? Heat??? Gimme son details

 

[KaGee]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

PB BLASTER is a penetrating, corrosion busting spray. But it at most auto part stores.<br /><br />Heat....TORCH!

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Hmmm... the gear isn't frozen in place, it can slide side to side. I just don't understand why it's not coming off. I imagine the end of the shaft is bigger than the middle. Can anyone confirm this? My manuals say nothing about this.

 

[whywhyzed]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Remove the 3 bolts on the rear triangular cover of the wormshaft (rear end of the intermediate top of the clutch hsg.) The round disc you see under that triangle piece is held in by an o-ring. Take the wood end of a hammer or something and knock it against the brass gear at the 10 oclock position to drive that little puck out the back- someone might have put some sealant on the o-ring.<br />Then the brass gear will come out the side.<br />Just did this today - mine is all of the sudden not tilting.<br />My motor runs fine, and the clutch housing looks good... I'm stumped... I think I'll have to do voltage drop checks -must be the relay connections...<br />Good thing I have a spare hammer blow coupling. I managaed to bugger the spring all up taking my motor out...

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Awesome, that's just the kind of infomation I need. Thanks.

 

[whywhyzed]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Also as I was removing the bottom motor bolt, all contorted like some sort of circus attraction, i was thinking..."how on earth am I going to get this bolt back in here"<br />So, I'm thinking I'll install a stud - I should be able to blindly maneouver a nut onto a stud upside down and backwards...

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Terrific sentiment. I had the same one myself yesterday. <br /><br />OK, so now I've got a mess. I've accepted that the internals of this tilt mechanism are incredibly corroded and stuck. I tried to hit the cap in the 10 o'clock spot to get it out. No dice. I took a punch and hit it there. I succeeded in making a dent in the cap. So then I drilled a hole in it to try to get it out, no luck. I've got to get something that will go in there and stick in there. I imagine that I might have started drilling on the worm gear as well. OK, so I'll have to replace that too.<br /><br />Yeah, this is ridiculous. But it will work when I'm done with it.

 

[Boatist]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

The two 50 amp fuses are on the starboard side of the motor near the started. They look like big cable connectors.<br /><br />The small gear is only held on the the snap ring but some one before may have hit end of shaft with hammer and swelled the shaft. Clean it with some fine sand paper or file. Use some liquid wrench and a gear puller and it should come off.<br /><br />Tap the end of the shaft or hit the tilt switch up and down to try and get the clutch pack out. When I took mine out the clutch pack was so gunked up I took the snap ring off and cleaned it all up. VERY IMPORTANT, if you do take the clutch pack apart understand it is very hard to compress enough to get back together. I took mine apart and put back together with a vice and two vice grips but still could not get the snap ring back on. I finally removed one disk and one spacer and got the pack back together. I was worried the motor would jump up in full reverse but it never has. Also me and another big buddy tried to force it up but could not. I belive when it got wet the disks swelled up. IF I ever take it back apart I am going to remove another disk and spacer. I would rather it kick up in full reverse than not kick up should I hit something going foward and take out the transom.<br /><br />Make sure you replace both seals behind the small gear, the big O Ring for the clutch pack cover and the drain and fill seals. Fill with motor oil and check for water after the first use.<br /><br />The tilt pins need to be cleaned and lubed. The way the wife and I did ours was to block up under the out drive then raise trailer tounge until had a lot of weight on the blocks. Took off the rubber stoppers then the two cap bolts and cap. Pulled the drive out about 1 inch and took the sleeve over the pins off. One held the drive while the other did the cleaning and re lube. Cleaned all the old grease off and re lubbed with OMC triple guard grease. Important to know the sleeves have holes in them to allow grease and water to get thru. They can be put on wrong so watch how they come off. Remember water pump water also goes thru the pins so make sure do not block the holes. I always greased my zerts twice a year but still the grease got hard and more like glue than grease.<br /><br />After putting mine back together will go full down with a 1/4 sec tap on the down tilt. Full up in a count of 3.

 

[whywhyzed]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Originally posted by mattsmall1972:<br /> I tried to hit the cap in the 10 o'clock spot to get it out. No dice. I took a punch and hit it there.

ouch ...I never told you to hit the cap. I wanted you to hit the brass clutch gear...although it should come out now...

 

[KaGee]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

 

[Boomyal]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Originally posted by KaGee:<br />

C,mon now KaGee. A little patience, please!

 

[KaGee]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Sorry... I'll smack myself. It's Friday... I already used my allotment till Monday.

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

I'm sure that I understand now why the gear won't come off easily - because I hit the shaft with a hammer to dislodge the shaft from the housing. That's ok, I can live with getting a gear puller and/or filing down the end of the shaft to allow the gear to come off.<br /><br />Thinking about the situation, although I haven't gotten the worm gear out yet, I believe that it will probably still be servicable as I haven't drilled much into the end cap and even then I only hit the very end of the gear if at all. I will definitely need a new cap.<br /><br />I had to go out with the wife last night, so hopefully tonight I'll be able to get back on the boat.<br /><br />As always, thanks for all of the help and comments.

 

[Bt Doctur]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Matt, can email detailed pics. DONT BE HAMMERING<br />EJDSR251@aol.com

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Hi everyone,<br /> I made a lot of progess just today. <br /> I managed to get the gear off the shaft by using a long bar that I have to hit the middle of the shaft outwards, so that the tilt geat has nowhere to go but off. So now it's off and that's done.<br /> The clutch appears to be in excellent condition, so I'm going to clean it and soak it in motor oil until I get this back together.<br /> Next, I managed to get the clutch housing off by wiggling it back and forth in the cavity. It finally made it out of there. <br /> The clutch housing was filled with gunk and was surrounded by gunk as well. I'm pretty sure that all of this gunk was preventing it from moving at all, even to come out.<br /> After removing the clutch housing, the worm gear moved freely. If I had not already drilled into the cap, I would have just left it in place. However, I had to complete the mission to remove the cap.<br /> Next, I drilled few smaller holes in the cap. I took some fine thread drywall screws and screwed them in there, then I was able to yank them out with the claw end of a hammer. FINALLY the worm gear is free.<br /> So now comes an important question:<br /> What does the end of the worm gear shaft look like? The end of my worm gear shaft has a small hole in it which houses a tiny cone-shaped piece of metal. I'm unsure out whether I drilled into this piece of metal or not. I know that the first hole I drilled straight into the middle of the cap did go past the cap, or at least to the end of the piece I am referring to. <br /> The piece of metal I am referring to is cone-shaped from where it fits into the shaft itself. However, past the end of the shaft, it's sort of got a "tooth" or a "tab" on the end of it. I've examined it and it does not appear to be something that I drilled into. However, I'd like you to confirm this for me if possible.<br /> One thing I noticed about this part is that when I put the worm gear shaft and this part into the cap, the worm gear can rotate only far in either direction before it must go again in the opposite direction. That is, it seems like a "stop".<br /> Thanks again for your help.

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Um, I figured out what this "stop" is. It's a piece of the punch I was trying to use to pry the cap out of the worm gear hole. <br /><br />But the worm gear shaft, even with a hole in the end of it, still seems very strong and is definitely usable.<br /><br />I've got a new cap and a new seal set on order. It *should* go back together a lot easier than it came apart.

 

[mattsmall1972]

Re: 1978 OMC 120 / 400 Stringer Tilt Motor replacement

Anyway, I made some progress today by getting the new tilt motor on the boat. I was able to check the hammer-blow coupling and it is in great shape. I put the worm gear and puck back into the baot and it turns great. Next, I put in the big gear to see if it turns. I noticed that the big gear is directional (or am I crazy) so I think it has to go in in a particular direction. I'll check the manual.<br /><br />As soon as I get my new gaskets and puck in then I'll get this thing back together. Thanks for everything.