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Alignment Tool

G

Guenter

New member
Question for someone who has an engine alignment tool that works properly: What is the diameter of the end of the alignment tool that properly fits into the coupling? The one I bought online slides through the gimbal bearing but it is too wide for the coupling.

Boat is 23' 1985 with 305 and alpha 1 gen 1 drive.

I may end up bringing the tool I acquired to a local machine shop for them to put on their lathe.

Thanks

Gunter
 
Tool Specs: According to MerCruiser service bulletin No 92-9,
the alignment tool must have the following sizes from front to back:
1.010" diameter, 2.200" long (section that fits into coupler),
1.150" diameter. 2.750" long,
1.375"diameter rest of bar (section that fits gimbal bearing inside diameter).
 
Well.....the alignment tool I purchased appears to have the correct dimensions according to the bulletin in the link (see first reply to my question....vielen dank, Dieter)......using my calipers it checked out perfectly.

This is puzzling to me. I have owned this 36 yr old boat 11 years, and I have uncovered no evidence that the engine was ever removed. I will ask the previous owner, but I don't believe that he had it for the full 25 years prior to T/F to my care. That being said, everything looks stock.

We were having a great boating season until one trip home when vibrations and clunking noises appeared. I took no chances, and we coasted home at 5 knots for close to a half hour....with no apparent worsening of the problem. Gimbal bearing was replaced two years ago, and presentation not consistent with another failing one (and bellows nice and dry....and bearing turns nicely by hand). Drive was exceptionally challenging to pull off.......it made me suspect an alignment problem......and moved me to begin by replacing U-joints (old ones were slightly scored). Tried in vain to reinstall drive, but I could not coax the drive to slip into the coupling (despite being able to rotate the drive/spline, etc).

Waited for alignment tool to arrive in the mail. Attempts to align using the tool repeatedly failed....could never get smallest diameter end into the coupling. I ended up relying on sight alone (and spotlight, etc) to move coupling into the center......or at least damn close enough to it so as to make it possible to easily reinstall the drive.........little to no force was required. Pulled drive out.......tried to insert alignment tool........still wouldn't go in to the coupling......reinstalled drive.....went for water test. Vibration gone (or substantially reduced). No abnormal noises in neutral. Grinding/clicking gear noise in Forward.....same noise, albeit to slightly lesser extent, in Reverse. No worsening/lessening of noises irrespective of drive being straight or aggressively turned in either direction.

Haven't checked the drive oil yet, but will do soon enough. I suspect that either upper or lower drive (the gears) are damaged, but I am speculating. Could the noises I hearing be due to a shifter cable issue (I believe that it was also changed a couple of years ago.....I think!?!)

I remain perplexed about the alignment issue......the misalignment and the tool itself. I believe that to get the coupling close to center, I had to raise one side of the engine more than the other........can't be a good sign.

What do you guys recommend I do next to properly diagnose the problem?

Gunter
 
Guenter said:
Well.....the alignment tool I purchased appears to have the correct dimensions according to the bulletin in the link (see first reply to my question....vielen dank, Dieter)......using my calipers it checked out perfectly.

This is puzzling to me. I have owned this 36 yr old boat 11 years, and I have uncovered no evidence that the engine was ever removed. I will ask the previous owner, but I don't believe that he had it for the full 25 years prior to T/F to my care. That being said, everything looks stock.

We were having a great boating season until one trip home when vibrations and clunking noises appeared. I took no chances, and we coasted home at 5 knots for close to a half hour....with no apparent worsening of the problem. Gimbal bearing was replaced two years ago, and presentation not consistent with another failing one (and bellows nice and dry....and bearing turns nicely by hand). Drive was exceptionally challenging to pull off.......it made me suspect an alignment problem......and moved me to begin by replacing U-joints (old ones were slightly scored). Tried in vain to reinstall drive, but I could not coax the drive to slip into the coupling (despite being able to rotate the drive/spline, etc).

Waited for alignment tool to arrive in the mail. Attempts to align using the tool repeatedly failed....could never get smallest diameter end into the coupling. I ended up relying on sight alone (and spotlight, etc) to move coupling into the center......or at least damn close enough to it so as to make it possible to easily reinstall the drive.........little to no force was required. Pulled drive out.......tried to insert alignment tool........still wouldn't go in to the coupling......reinstalled drive.....went for water test. Vibration gone (or substantially reduced). No abnormal noises in neutral. Grinding/clicking gear noise in Forward.....same noise, albeit to slightly lesser extent, in Reverse. No worsening/lessening of noises irrespective of drive being straight or aggressively turned in either direction.

Haven't checked the drive oil yet, but will do soon enough. I suspect that either upper or lower drive (the gears) are damaged, but I am speculating. Could the noises I hearing be due to a shifter cable issue (I believe that it was also changed a couple of years ago.....I think!?!)

I remain perplexed about the alignment issue......the misalignment and the tool itself. I believe that to get the coupling close to center, I had to raise one side of the engine more than the other........can't be a good sign.

What do you guys recommend I do next to properly diagnose the problem?

Gunter
Click to expand...

I suspect you have two issues:

What ever is making the clunking in the drive. Would check the lube for metal and water. Was there drive oil in the bellows? If the input shaft seal leaks the oil goes into the bellows and the upper gearset and bearing run dry. You can take the top cap off easily to see what they look like.

IProbably your rear motor mounts have sunk/dropped and thats why you cant get the alignment bar in. Look through the gimbal bearing with a flash light I suspect you will see the coupler is much lower than the gimbal. These motor mounts are pressed into the flywheel cover where it bolts to the inner transom plate. I think BT dr has in the past posted pics of a press he made for changing these out of the cover.

The shift cable I think would just be an issue if it wasnt fully in gear, so if you were in gear and had forward thrust I dont think thats your issue.
 
As a follow up on alignment tool.
I have both.
Original for older alpha one and newer with multi Stepped shaft for Newer drive shaft with O-ring.

Both measure at 1.010"
 
I agree with the probability of either the transom motor mounts collapsed (causing the misalignment) or the couple gave way (causing the vibration and misalignment)

The coupler can fail but still function if the rubber does not sheer away from housing.

If transom motor mounts collapsed that could also cause vibration due to misalignment and put a lot of pressure on input shaft and coupler. If this is the issue it most likely was bad for a while and over time finally got to the point of severe misalignment

The fact that you are having trouble getting alignment tool into coupler points to either of above.


Of course you seem to be able to adjust enough to get drive in. This also may point to motor mounts as the change would be about 1/8-1/4 inch of drop leading to that amount of adjustment.

Unfortunately the most likely course of action may be to pull engine and look at coupler and transom mounts
 
OK. I did not realize that the transom engine mounts were inserts/replaceable (Is it safe to assume that the front ones are similarly worn and worth replacing, too?) I suspect that is my principal problem, and that the other problems downstream with the drive were precipitated by this. I have never pulled an inboard engine, so that will be a new experience. I'm in my 50's now, but started out as an Engineering Student/PT Mechanic. I switched gears in my 20s, pursued a career in Medicine, and ultimately became a Forensic Psychiatrist. I still love to turn a wrench, however (when I'm not bending some minds:rolleyes:)........so long as it all goes smoothly, of course. The old boat I have was built well for Georgian Bay waters (I live north of Toronto), and if the engine is still good (I will check compression), it may still be worth my while to pull the engine, replace the mounts.........and replace the entire drive with the commonly available aftermarket (SEI) unit (I'm currently assuming that my upper and/or lower gearcase was damaged by all of this)

I am new to this forum. I used to be a very active member of a forum for Audi V8 owners. I had two of those old beasts, and kept them running forever thanks to the insights and support I received.

Thank you to all for your assistance. There are plenty of marinas around here, but I have not yet met a local marine mechanic that I feel I can trust to do a good job on my old beast.

Gunter
 
Well, you have gotten away with 11 years without major maintenance so I think you're doing pretty well all things considered. I think that you are at a turning point here. it's time to decide whether to put potentially thousands into this thing or move on and let it go live at someone else's house. Virtually every boat is for sale, so maybe you've had your eye on some other one that suits your fancy more? Maybe it's time to make the leap.

If you decide to stay with this, since you cannot picture yourself with any other boat, then it is time to do what you've been putting off. Honestly getting the engine out isn't that tough. It's the stuff you need to do that's probably going to be the hardest part which involves a major cash-ectomy of the wallet. Sadly for you this boating season is over. Start looking now for a good used drive if you don't trust the one you have. There are plenty to be had and if you make it known at the local boat yards and repair shops that you're looking it'll start raining Mercruisers. Really. I wouldn't buy one of those SEI remanufactured drives given that there are so many genuine ones still around. Maybe you should just pull your drive and take it to a Mercruiser shop for a good going-over. I did that with my current Bravo 3 (that I got used) and the bill was only a few hundred. As for the engine, I would recommend a compression check and leak-down test to determine overall health. After that all new seals belts hoses. Maybe have the heads reconditioned followed by a nice new coat of paint. New manifolds, elbows, etc. basically a mini overhaul so that you are sure that the next time you have the Toronto Bikini Tanning Team aboard there won't be any embarrassing clunks.
 
Guenter said:
OK. I did not realize that the transom engine mounts were inserts/replaceable (Is it safe to assume that the front ones are similarly worn and worth replacing, too?) I suspect that is my principal problem, and that the other problems downstream with the drive were precipitated by this. I have never pulled an inboard engine, so that will be a new experience. I'm in my 50's now, but started out as an Engineering Student/PT Mechanic. I switched gears in my 20s, pursued a career in Medicine, and ultimately became a Forensic Psychiatrist. I still love to turn a wrench, however (when I'm not bending some minds:rolleyes:)........so long as it all goes smoothly, of course. The old boat I have was built well for Georgian Bay waters (I live north of Toronto), and if the engine is still good (I will check compression), it may still be worth my while to pull the engine, replace the mounts.........and replace the entire drive with the commonly available aftermarket (SEI) unit (I'm currently assuming that my upper and/or lower gearcase was damaged by all of this)

I am new to this forum. I used to be a very active member of a forum for Audi V8 owners. I had two of those old beasts, and kept them running forever thanks to the insights and support I received.

Thank you to all for your assistance. There are plenty of marinas around here, but I have not yet met a local marine mechanic that I feel I can trust to do a good job on my old beast.

Gunter
Click to expand...
Front mounts have adjustment to them so probably are fine.

hard to say with out seeing it given age is look for transom rot as well drill a few holes down low by out drive see if transom wood is ok

when u look in through gimbal bearing with a light is the coupler low ? What do splines in coupler look like ?

i wouldn’t assume your drive is damaged what u describe could be from a damaged coupler drive may be fine. Figure out what’s going on first
 
Look closely at the teeth in the coupler. They are aluminum and softer then the shaft. Sometimes as a coupler wears the splines in the coupler will get pushed to the middle. They will look like they have sharp edges. If they have an edge that looks like a knife, that's what is keeping the tool from sliding in. You can use a hammer and pound the tool in knowing that the coupler is almost worn out and about to fail or replace the coupler.
 
Stringers collapsed. Both, but starboard side far worse. Engine compression test OK. Pulled engine out, but in the process both male and female electrical connectors damaged (several pins tore away from electrical wires, for eg). Local expert believes he can rebuild stringers. He still has to look at the transom now that engine out. Haven't been quoted a price yet.

When I disconnected the water inlet hose between transom assembly and the engine, there appeared to be some sort of thick rubber spacer/washer there (that the hose appears to fit over) that don't recall ever encountering the likes of in my years of automotive mechanical work. What's the function of that? Replace?

If if continue on and reinstall the engine, I'm tempted to just eliminate the male/female connectors and just manually solder (fairly permanently) the wires together.

My wife seems inclined to salvage the boat..........
 
Stringers shouldn't collapse. Too many times manufacturers depend on the wood to do the work when the wood is merely a form for creating a rigid beam built up of layers of glass cloth and resin. Since the wood form can't be removed it is left in place.
If your stringers are no good it means the builder cut corners on the construction and/or water made its way inside and rotted out the wood.
Sometimes you see bare wood stringers barely tabbed to the hull with a few measly strips of glass cloth. Bottom line the hull is probably not worth the cost of repair. Sorry for the bad news. If you do go forward with repair use a material inside the stringer that won't absorb water such as closed cell foam, coosa board, or some of the pre-engineered composite stringers. Wood is cheap, which is why they use it.

PS Don't use solder connections on a boat. It is strictly forbidden by the ABYC. Crimp only.
 
PS the old Carver Mariner I tried to restore had this very problem. The stringers were 2x12 lumberyard pine or some crap and they covered those with only two layers of roving. In addition, limber holes were cut in the bottom edges but never treated so water got into the wood that way. The wood rotted, the wussy glass structure collapsed and the boat required ripping out the entire floor to get at all the rotted wood and useless garbage construction. I did the demolition and then threw in the towel on that one.
The stringers should be able to support the hull without relying on the wood. Again, the wood is merely a form.
 
Guenter said:
How about 2 X 2 solid aluminum bar for the form?

Boat is a 23'

The floor itself looks great.
Click to expand...

The floor is typically the last part to rot out as they rot from bottom up. Generally you have to tear the floor up to get at stringers under the floor. Would have the local guy who may be doing the stringer work check the entire structure before doing anything.
 
If the engine supports collapsed, then the entire structure of the hull is suspect including the transom. You can actually use cardboard boxes to make the stringer forms. These will be built up with several layers of woven roving wrapping them. Build them with about 1/4 inch wall thickness at least. That's 4 layers of roving. I wouldn't use foam of any kind as it can suck up water even tho it won't rot.
 
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Twenty years ago (in my youth of 50 yrs.) I did a complete gutting of a 19' Baretta down to the bare hull. Only did it because the engine was fairly new and OD was in good condition. Fabricated new stringers, transom and floor. All wood was treated with CPES (clear penetrating epoxy sealant) then glassed with epoxy. Also replaced engine mount bases. I bought new boat and engine wire harnesses due to the old ones being corroded. I found the foam encased fuel filler hose was rotted and leaking fuel into the floatation foam which also was water logged. Installed a new rear fill fuel tank. Did not install any foam. It cost me a small fortune. BUY A NEWER BOAT and part out the engines and drives.
 
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