Merc Rear Motor Mount: Is this bad?

[life_aquatic]

Boat: '89 22 ft Galaxy walk around cuddy
Motor: '89 Mercruiser 170 (engine #OC786181)
History: Bought the boat last fall. Let a shop tuneup and check the outdrive before they winterized it. They replaced the bellows, gimbal bearing, shift cable, and yoke assembly.

This spring I have been testing it out on a reservoir before I feel ready to take it to Lake Erie (I'm now happy I've taken this precaution). On saturday I noticed a rattling noise when turning, but being alone had a hard time diagnosing. At home I noticed the power steering belt was extremely loose and it appears that the wheel that turns the belts in the front of the engine (sorry I couldn't figure out what this is called) was rubbing against the front motor mount support arm. A bit more poking around (after studying my manual, and the forums) and I noticed that right rear motor mount bolt (if you're facing the front of the engine) has some play in it. In other words I can move it up and down by hand maybe 1/4 to 1/2 inch. However I couldn't turn the bolt by hand (I didn't have any tools on me when I discovered this).

Anyone venture to guess what might be wrong back there? Can I just attempt to tighten this, or would I be in need of an alignment as well?

I'm also surprised that the shop didn't notice this when they had the outdrive off. (unless, of course, it just happened) I didn't ask if they aligned it when they did the work on the outdrive, but I just assumed so.

I pretty savy with fixing things, usually just deficient in tools. Wonder if this is something I should leave to a shop?

 

[Bt Doctur]

Re: Merc Rear Motor Mount: Is this bad?

What part is moving up and down? the large washer, the spacer, the whole bolt.?

 

[Fishermark]

Re: Merc Rear Motor Mount: Is this bad?

right rear motor mount bolt (if you're facing the front of the engine)

In nautical terms, that would be the port side.

There should be no play at all. I would ask your shop if they did in fact check the alignment.

 

[life_aquatic]

Re: Merc Rear Motor Mount: Is this bad?

Yes it is the port side. :redface:
I spend on lot of time on the water, and always forget those terms.

I'll double check if the whole bolt is moving or if it is something else.

 

[Don S]

Re: Merc Rear Motor Mount: Is this bad?

When was the last time the outdrive was removed and the alignment checked and the bellows checked for water, the gimbal bearing and ujoints checked.?

 

[mkast]

Re: Merc Rear Motor Mount: Is this bad?

I'm also surprised that the shop didn't notice this when they had the outdrive off. (unless, of course, it just happened) I didn't ask if they aligned it when they did the work on the outdrive, but I just assumed so./QUOTE]

Shops today are getting tired of an owner/operator complaining, "I didn't tell you to do that, I'm not paying for it.
Then there is always the shop calling, "Engine needs to be aligned."
The owner/operator will say, "It's been okay for years, you're just trying to lighten my wallet."
If you tell the shop to, "Look it over", the list (cost) will probability scare you away. Then you'll look for a mechanic that will do exactly what you ask for, and maintenance items will not be inspected.
The only suggestion I have is to get the Mercruiser maintenance manual for your power package and start reading it, at least you'll have a working knowledge of the unit, and what maintenance should be completed and when.

 

[life_aquatic]

Re: Merc Rear Motor Mount: Is this bad?

Ok here's the update and answer's to some reply questions.

DonS - the things you mentioned were done in the fall by the shop (Except I'm not sure about the U-joints; check my original post, I copied the major things that were done from my invoice to my post.) Bear with me, I'm don't feel very knowledgeable about all the bits and pieces of an outdrive, as I've never seen one disassembled, only diagrams.

Mkast - I don't want to sound like I'm blaming the shop. I think it's a pretty good place. I just thought that from what I've read on these forums, if you have the outdrive off to do the repairs listed, alignment would be part of the labor involved in making that particular repair. I will definitely ask form now on.

Bt Doctor - It was in fact the whole bolt that was moving.

When I got home to my tools tonight, I started tightening the bolt with a ratchet. It immediately started tightening up, but then seemed like it wasn't tightening significantly. I could barely get my hands in to do the job, so I couldn't make more then maybe quarter turns and never applied any significant torque. My plan was to see if I could tighten it significantly, then get a torque wrench to get it to spec.

So instead I turned it loose and pulled the bolt out. The bolt looked OK, but it had threads that must have come from mount.

At this point I think one of the previous owners must have cross threaded he bolt. I think the engine was never solidly mounted when I bought it. I thought the amount of play in the engine was normal for dealing with vibrations, etc. Chalk it up to inexperience with I/O.

So what are my options at this point? Did I buy some expensive electronics and fishing equipment? I love fixing stuff, but I have a limit.

 

[Bt Doctur]

Re: Merc Rear Motor Mount: Is this bad?

Courtresy of Don S
Just below D and out of site is the ny-lock nut the bolt goes to. It`s held captive by the housing.I`d thread it back in and try tightening it again.If you cant tighten it the nut is missing and may need the motor pulled up some to insert a new nut.

 

[life_aquatic]

Re: Merc Rear Motor Mount: Is this bad?

Man that last post has me feeling much better. I remember reading about that nut in some other post. But I'd scene the pic you provided before and since there is no nut (nor in the manual) I assume the nut must have been on some different mounts.

Anyway, in a feat of dexterity I was able to fish the nut out. It was toast. Threads were mostly gone and no nylon left in it. I'll get a new nut, maybe new bolt too, and put it all back.

If the shop didn't do an alignment, I think I'll have them do it. Don't know if I feel up to it. If they did do an alignment - should I redo it after putting the new nut and bolt in?

 

[life_aquatic]

Re: Merc Rear Motor Mount: Is this bad?

Talked to the shop today. They said they didn't do an alignment, but would have told me if it was needed.

So if I put the new nut on the rear motor mount, should I do an alignment? I won't be changing the fiber washer or anything.

 

[haulnazz15]

Re: Merc Rear Motor Mount: Is this bad?

How in the hell can you tell if an alignment is needed or not by looking at it?!! It take two seconds to slide the alignment tool in there to verify! Maybe because the drive went on easy it was assumed to be aligned properly.

 

[Fishermark]

Re: Merc Rear Motor Mount: Is this bad?

How in the hell can you tell if an alignment is needed or not by looking at it?!! It take two seconds to slide the alignment tool in there to verify! Maybe because the drive went on easy it was assumed to be aligned properly.

Maybe the shop did in fact put the alignment bar in and checked - maybe that's why they said it didn't need to be aligned. Nowhere do they say they simply "looked at it."

Having said that, it would be in your best interest to buy an alignment tool and have it on hand for future use if nothing else. If you ever plan on doing things yourself with this boat, it is a handy tool to have and you will have it to check the alignment yourself. You can get them online for very little money.

 

[mains]

Re: Merc Rear Motor Mount: Is this bad?

I have mercruiser 120 and at idle the boat shakes when bump up gas it stops shaking,any ideas please.

 

[Don S]

Re: Merc Rear Motor Mount: Is this bad?

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