engine mount problems

[Tripp Halbert]

1996 Johnson 70hp. Motor is vibrating bad. Lots of play side to side near this area. I suspect These bolts to be the issue since the nuts on them were rusted badly. I removed the nuts and damaged the threads. Tried forcing a new Ss nut on with no luck. Tapping hw will not fit in this area. Any ideas guys, please help!

Site will not let me upload high res pics but email me if you need them as I really need advice on this Not allowed per rules - iboats Mod Team

 

[emdsapmgr]

To see the original factory exploded parts diagram, check out this website: epc.brp.com Look for your model year under Johnson. Then find the diagram called "midsection." You will probably find that to repair this you will have to remove the powerhead in order to access this area. The indicated rubber mount may also be bad, P/N 436394

 

[Tripp Halbert]

That's what I was afraid of. There's no other way around removing the power head?

 

[F_R]

I don't think you can do anything with that without removing the powerhead to get at the mount.

 

[Tripp Halbert]

Thanks for the quick responses guys. Looks like I will pull the lower unit. And try to pull the power head. Any additional tips or advice? I will be using pb blaster to help loosen everything

 

[Joe Reeves]

Tripp... Before dismantling the engine in suspecting faulty motor mounts, keep this in mind. If the engine is attached on the boat with everything hooked up "including" the mechanical steering linkage etc... and you can grab the lower unit cavitation plate and shake the engine sideways "inches" to each side WITHOUT moving the steering arm of the engine... the problem has always proven to be that the splines on the bottom of the steering arm, the ones that are splined to the bottom motor mount retaining bracket, are "stripped".

These splines of the steering arm that are splined to the bottom motor mount brackets is actually the connection point that steers the engine, NOT the motor mounts. When the splines strip, the engine, although it does steer after a fashion, shakes all over the place. Hellava job in either case.

Check those splines, let us know what you find.

 

[gm280]

In addition to the previous comments, I would absolutely positively purchase the original "Factory Shop Manual" for your engine before removing even one bolt or nut. There is no better step by step procedure then the manufacture's model specific shop manual if you are seriously going to dismantle any engine or section of an engine like it appears you are going to do... The time saved reading and seeing the pictures is money very well spent...

 

[Tripp Halbert]

Yep the first thing I did was make sure the metal arm assembly was all tight. I have play side to side past that point. Wish my fix was that easy though! Looks like two of the lower unit bolts are not going to come off without a fight, as I suspected...Probably will snap and I will have to drill them out. Starboard side ones both came off easily and the other two aren't budging...broke one craftsman ratchet already

 

[gm280]

Make sure you take tons of picture as well because even though you THINK you will remember how everything goes back together, if you have to order parts and it takes a while, you will forget how everything goes back together. Not so much the larger common sense things, but the little parts that makes you scratch your head and say, does this actually go to the engine? Been they and certainly done that... Multiple angles of everything has save my butt a few time now... JMHO!

 

[Tripp Halbert]

Thanks gm280, I will make sure to do that cause ur right, there always some washer or o ring that u have in the end and start freaking out.

Unfortunatley, 2 out of 5 bolts snapped on the lower unit. I did everything I could to avoid it but there was heavy salt corrosion inside on the threads. I know of ez-outs, but what methods have u guys had success with in getting these broken bolts out?

 

[F_R]

Tripp... Before dismantling the engine in suspecting faulty motor mounts, keep this in mind. If the engine is attached on the boat with everything hooked up "including" the mechanical steering linkage etc... and you can grab the lower unit cavitation plate and shake the engine sideways "inches" to each side WITHOUT moving the steering arm of the engine... the problem has always proven to be that the splines on the bottom of the steering arm, the ones that are splined to the bottom motor mount retaining bracket, are "stripped".

These splines of the steering arm that are splined to the bottom motor mount brackets is actually the connection point that steers the engine, NOT the motor mounts. When the splines strip, the engine, although it does steer after a fashion, shakes all over the place. Hellava job in either case.

Check those splines, let us know what you find.

Agree 100%, Joe. But the guy has already messed up the bolts that hold the upper mount to the steering arm. I'd say he has his work cut out for him, considering the bolts he has already busted off, and hasn't even gotten started yet. What do you think?

 

[Tripp Halbert]

Well u can leave this post as ur input is solely negative.

I have removed all 5 bolts from the lower unit. 2 broke at the threads. I remove the r clip and push in the elbow shifter piece. Now the prop is stuck in gear and the lower unit won't come down? Any ideas you guys? I'm a green horn... :/

I

 

[Joe Reeves]

Agree 100%, Joe. But the guy has already messed up the bolts that hold the upper mount to the steering arm. I'd say he has his work cut out for him, considering the bolts he has already busted off, and hasn't even gotten started yet. What do you think?

F_R: Yes, unfortunately such is the case but it happens to all of us at various times even though we know exactly what we're doing. Broken bolts, salt frozen an/or corroded threads on bolts/screws/studs... quite hard to avoid that scenario. From what I've read of this problem, the powerhead and lower unit would require removing anyway. Quite a project encountered here.

Well u can leave this post as ur input is solely negative.I

Tripp: I've reread all the posts/replies and see nothing negative being posted... perhaps you've misread something? The extremely tight, frozen bolts, nuts, etc that you're encountering... of course it's too late for the ones that have already been broken... BUT... in the future (if you haven't already) use a hand held propane torch to heat the aluminum surrounding the tight threads. Aluminum expands faster than steel and the heat helps to free those super tight items.

 

[Tripp Halbert]

Thanks. I tried that as well as tapped with a hammer as I turned left and then back right. Got them about a 1/4" out and then snap!

 

[gm280]

Tripp Halbert, Seems we've all been there and done that too. So you are not alone with such things. Now you have to disassembly things just to get the remaining bolt studs out, retread the holes and replace with new bolts. So picture taking time IS now! And the shop manual is NOW also. Some times there are easier ways to accomplish things that you may have never thought of before. Do post pictures on here so we can see exactly what you are seeing and working with. Pictures on here are worth more then a thousand words. There really do say so much more then you'd imagine and can keep you from doing things the hard way... With bolts already snapped, there could be ways to still remove the broken studs if you can post the pictures of them... JMHO!

 

[Tripp Halbert]

Gm280 i gotcha. here are some pics of the broken bolts. Let me know what yall think. I'm about to start working on getting the power head off now. Is there a way I can upload a video on this site?

 

[Tripp Halbert]

No Title

 

[F_R]

Sorry if I offended you. But the original question concerned the two Grade-8 bolts that hold the entire upper end of the motor to the boat----the bolts that you told us you damaged. I didn't say that, you did.

All these other bolts are secondary to dealing with the original problem. That problem cannot be ignored, those two bolts hold the motor to the boat.

And Joe pointed out the lower mounts/splines as being a likely problem in the first place.

Yes, you are going to have to deal with a lot more corroded bolts before you are finished. That is not meant to be negative, just reality.

I'll leave you alone now, as requested.

 

[gm280]

Tripp, yes there are ways to up load video. But being how I've never done so, I'll let the pros answer that question.

I see you do have some work ahead of you now with those broken bolts. I know some use a drill and "Easy-Outs". The only problem I see with Easy-Outs are the sad facts that IF you break one off, you are really screwed... That is probably the hardest situation to ever come out then and fix. I'd approach those broken off bolts with a vice-gripe where you can grab something, and apply some penetrating oil(s) and heat and work them slowly back and forth all the way out. The ones broken off below anything to grasp, I'd take a file (or grinder) and flatten the tops (if possible) so you can drill out with progressively larger drills and see if you can collapse the remaining threaded sections and remove. Either way, make sure you both re-tap (chase) the threaded holes AND clean out all metal shavings...

 

[Tripp Halbert]

Okay so I have everything dismantled down to the 6 bolts that hold the mid section to the powerhead. One came out easily but had a cloud of white dust trailing as it dropped out. At this point I became very discouraged. The remaining 5 were very very tight and I believe them to need a lot of heat not to break. I'm considering taking it to a shop and have them take this on. If those break inside, I'd be royally F'd. What do you guys recommend?