Motor alignment problem-gctid802360

[sketch96]

When I pulled my bravo 2 leg off in the fall it was very hard to get off. I have noticed some wear on the teeth of the input shaft also. Now it's spring and I just went to try to use my new alignment bar and it will only engage into the coupler 1 inch. I've been raising the front mounts almost to the point of running out of threads on the mount stud. Still goes in one inch and bottoms on something. Sounds like metal to metal contact. Solid. Looking at the grease tracks I do now have them looking fairly even. Seems like I need to raise the front a bit more yet. But close. The teeth marks were heavy on the bottom to start so the alignment was off.

What could be hitting? It's solid contact and I can not even tap it in any more than an inch.

It's a 1995 2859 7.4l with bravo 2 leg. I've been looking all over the Internet but can't seem to find anything quite like what I'm experiencing.

The tool I bought has 3 steps. The first small portion that engages the coupler is approx 2 1/8 inches long. Next step is approx 2 3/4 inches long the steps up to the portion that engages the gimbal bearing.

What could it be bottoming against?

[builderdude]

The drives input shaft may have only been engaged into the coupler the 1 inch you've refered to. If the alignment was really off like you've described the coupler could have worn a bur or burs around the interior of its splines, that may be what your hitting. A bright LED light on the coupler splines in the engine bay may help you see if this is the case. A smaller wood dowel could also help determine the original depth of the splined area.

[SprinterX]

Could the aft rubber engine mounts have fatigued to the point where they are sagging? This could result in an improper fit of your alignment bar.

[2850Bounty]

"sketch96" post=802360 wrote:
When I pulled my bravo 2 leg off in the fall it was very hard to get off. I have noticed some wear on the teeth of the input shaft also.

[color]#000088 wrote:
This splined shaft is carbon steel.

If the male splines show signs of wear, you can almost bet that the female splines within the drive coupler are wearing also.

I would give this some serious thought before going back together. [/color]

Now it's spring and I just went to try to use my new alignment bar and it will only engage into the coupler 1 inch. I've been raising the front mounts almost to the point of running out of threads on the mount stud.

[color]#000088 wrote:
Not sure what...... but something is wrong.

[/color]

Still goes in one inch and bottoms on something. Sounds like metal to metal contact. Solid. Looking at the grease tracks I do now have them looking fairly even. Seems like I need to raise the front a bit more yet. But close. The teeth marks were heavy on the bottom to start so the alignment was off.

What could be hitting? It's solid contact and I can not even tap it in any more than an inch.

It's a 1995 2859 7.4l with bravo 2 leg. I've been looking all over the Internet but can't seem to find anything quite like what I'm experiencing.

The tool I bought has 3 steps. The first small portion that engages the coupler is approx 2 1/8 inches long. Next step is approx 2 3/4 inches long the steps up to the portion that engages the gimbal bearing.

What could it be bottoming against?

[color]#000088 wrote:
Can you borrow a lighted bore scope?

If so, go into the female splines and take a look see.[/color]

[color]#000088 wrote:
This should help you understand what the goal is.[/color]

[attachment]35026 wrote:
DriveCoupleralignmentexplained1-2-3.jpg[/attachment]

[attachment]35027 wrote:
DriveCoupleralignmentexplained3-2-3.jpg[/attachment]

[Chief_Alen]

Back mounts sagged / or stringer .

The transom mount moved down, rot.

Agree with the coupler being worn, how worn you have to see it.

They make a grease strictly for " splines " takes up the space better between the splines .

[2850Bounty]

"Chief Alen" post=802389 wrote:
Back mounts sagged / or stringer .

The transom mount moved down, rot.

[color]#000088 wrote:
That is always a possibility..... however, sketch96 suggests that he thinks that he needs to "raise" the front of the engine..... and I'll assume that he means in order to reduce the shaft/coupler friction and head towards better alignment. [/color]

.

[Chief_Alen]

Consider this ... something moved . Otherwise the tool would have slipped in like butter.

If a person can tighten down the nuts that hold the transom shield more then 1 turn the transom is suspect !

The rear mounts to the stringer might need to be shimmed, if the stringers are not mush.

No way a person has to adjust the front mounts till there are no more threads, agreed ?

Probe the stringers around the mounts !

[sketch96]

When I first inserted the alignment bar I had heavy marks on the bottom and almost nothing on top. Which means the front of the motor was low. So I don't think I have an issue with the rear mounts sagging or rotten transom. I went to adjust the front mounts and one side was seized and the stud was turning in the mount. I replaced that mount then proceeded to raise the front of the motor. The bar now goes in to the first inch of the coupler much easier but only 1inch then bottoms against something. Sounds quite solid.

The PO said he did replace the coupler when he had the motor rebuilt, apparantly it has only 300hrs approx. The u joints on the prop shaft also look like new. The gimbal bearing looks and feels like new also. Can't figure out the why the leg was so hard to remove. Had to use pry bars to get it off.

The teeth on the prop shaft show some wear but are not to the point of needing to be replaced. Not worn to sharp edges, still have a nice square edge for lack of a better term.

I am going to get a small wire brush and get in and clean the splines on the coupler and have a better look today. It looks like the prop shaft was inserted approx 2 inches by the wear on the teeth. So I don't know why the bar would not insert about the same. But maybe there is a burr on the coupler teeth........hoping not as it looks like it would be quite a job to have to slide the motor forward enough to do that.

[sketch96]

I did probe into the stringers when I was replacing the one front mount with a pick. They feel a bit soft but not bad. I had to really push to get the end to slightly penetrate the wood. Now from. What I understand the wood is not what holds the motor but is only there to form the fibreglass around and is the fibreglass that is actually the support structure?? I don't see any bulging or hairline cracking anywhere around the front mounts. The lag bolts went back in and seem to tighten down well. The new mount had a taller stud than the old mount. Looks exactly the same just has a taller stud approx 1/4". So the new side still has lots of threads left. The old side has maybe 2 or 3 threads left above the nut..........could it be that they realized this and made the new mounts taller for this reason?? Just guessing.

If the rear mounts were bad and sagged or the transom was rotten would I not be needing to lower the front of the motor? I'm sure there is some degree of moisture in the transom of all boats that are 20+ yrs old but this one isn't showing any sagging at the rear of the motor so far. I am expecting to have to one day pull the motor and change the fuel tank, stringers, transom wood but want to get a couple years of use before I have to tackle that.........hoping! I bought this boat knowing at 22 yrs old it will need all that at some point but I am not afraid of that kind of work. Love it actually. Just want to get some time on it first!!!

[2850Bounty]

"Chief Alen" post=802393 wrote:


The rear mounts to the stringer might need to be shimmed, if the stringers are not mush.

[color]#000088 wrote:
Alen, just curious...... what rear mounts to stringers are you suggesting?

These are a four point engine mounting system. Two foward side engine mounts, and two flywheel cover-to-inner-transom plate mounts.

[/color]

.

[Smitten]

Hey Sketch. Have you bumped the starter? Sometimes when I'm changing drives I've had to do that to rock the flywheel a hair and it slides right in. Not sure what I'd done while the drive was off to cause the misalignment. Don't mean to have you chasing your tail here and no, I'm not a qualified mechanic. You would want your mounts right back where you started for this I'd think. Good luck.

[Chief_Alen]

Something dropped in the back ... Period .

Next we are going to be talking about a fuel tank replacement for this boat.

[SprinterX]

When we pulled our B2 drives last year one was quite difficult to remove and we found the alignment off. (special thanx to the marine shop that ef''d that up when they installed the new engine the year before) Further inspection of the propeller shaft splines showed very little wear. After cleaning out the drive coupler splines I was horrified to find virtually 80% of the material worn away. They were little pointy spikes. I don't now how it didn't shear and leave me SOL. (special thanx to the marine shop that ef''d that up when they installed the new engine the year before)

Make sure you clean out those drive coupler splines and perform a detailed visual inspection. Be sure to use the proper grease for those U-joints and splines. Very important!

I checked my rear mounts for sagging and while they seemed fine I changed them since the engine was out for a new drive coupler. (special thanx to the marine shop that ef''d that up when they installed the new engine the year before)

Best of luck.

[sketch96]

Thanks for all the replies guys!

Chief Allen.....not sure why you figure the rear of the motor dropped? If that was so would I not see heavy teeth marks on the top of the alignment bar? Or if it dropped too much I should not be able to get the bar started in the coupler at all?

I am expecting a tank and transom replacement at some point

[Ruffryder]

No rear mounts to the stringer, but inner shield rear mounts can collapse, sag if the bushing is worn out.

We usually don't even touch 2 front engine mounts unless it was completely removed or out of whack inch:

Majority of the times, the bearing can move in the carrier.

The gimbal bearing can pivot in it's housing... You'll have to lightly tap the tool a couple of times to get it to line up when you START the alignment procedure.

Hard to believe no one mentioned this :whistle: