how do you align an engine?
 

I've got a staggered setup with #5's. How do I make sure the plug in engine is aligned properly? Even the forward engine would probably benefit from proper alignment with driveshaft. How do I go about it? Thanks

We moved Mild Thunders engines back this year and he had a pretty nice alignment tool for the SSM drives.
Looks the same as a bravo except it has a disk that fits in the gimbal. Pretty easy with 2 people

I'll find out where he got it. Can you give a description of how it's used?

Take drive off, stick alignment tool thru to the trans, move motor till the ring lines up perfectly in the gimble .. kinda hard to explain but easy once you see it.

Sounds easy enough, thanks. What would I want to do with the one connected to the driveshaft?

SSM Alignment
 

I know this is a bit old but how do you know what position to put the drive bell housing (helmet) in? It turns left to right and pivots up and down so where exactly is the correct starting point? Also how far in does the trans plug in and how much tolerance is there? I'm trying to reinstall engines and the front and rear plates don't mate up well to all of the angle brackets. I need to move something, just trying to figure out what to move and in what direction.

eyeball up the bell housing (helmet) as straight as you can. once you get engine close, you may see where steering or tilt is a tiny bit off center and then center the helmet. but the alignment shaft is turning around a point a good foot forward of the steering-trim axis. with offshore mounts it is best to have engine hanging from hoist to align it. and the trans goes in till it bottoms out in the hole, and that is your non-moving point. I think alignment is simpler with trannys. you just swing engine till disc aligns with register point in bell housing. you don't have the feel issue of the gimball bearing to coupler alignment. we should probably stick with the term helmet. everybody thinks the bell housing has a flywheel inside it like on a car...

That is the same setup that I use on BRAVO drives. I had the plate made at a local machine shop.
The gist of the plate is that it fits tight to the shaft ( can't wobble ) , it is round about 1/2 inch bigger than the inner hole in the helmet and has a step that is just small enough to fit into the hole in the helmet. When the engine is aligned the shaft slides in and out freely AND the plate fits flush and centered INTO the hole in the helmet. The plate will show you if the engine is off side to side or if the rear mounts are at the right height.
Attachment 568506Attachment 568507Attachment 568508

That is the shaft I had machined to work with my IMCO extension box. It has all of the dimensions as the stock Merc. shaft just a lot longer.

Thanks for the info

i have one of those super special alignment tools too !

ez riser,
pic 1 is shaft, left plate is bravo, right plate is trs.
ive only aligned alpha and trs, but i gotta think speedmaster is same as trs.

basically on a plug in transmission engine you put the shaft thru the transom assy and into the transmission tailstock splines
theory being tailstock to inner transom plate mounts gets you in the ball park.

slide the plate on and if the plate lines up flush all the way around, it's aligned (pic3)

if there is a gap between the plate and the gimbal housing like in pic 4, it's not aligned.
as example pic 4 the front of the engine has to go down.

so you need to find i.d. speedmaster spline in the tailstock, so you can have a shaft made,and have a plate made that fits into speedmaster gimble housing.

no way do i believe anyone does an alignment with that much money and NLA parts on the table w/out a special tool

did you pull engines ?
did you pull angle aluminum off stringers ? - did you mark their locations ?
those angle aluminum are usually marked and drilled during installation / alignment, they don't come pre drilled as far as i know.
(if so someone tell me where to get them so i can save myself alot of work)

Very nice Safari, thanks. Yes I pulled engines and angles. There is no play in the stringer holes and very little movement in the angle holes, not nearly enough to get the plates to mount up properly. I'll get the right tools and figure out what's not right, hopefully something is and I can bring everything else to it rather than starting completely over. I didn't pay any attention during disassembly as to how much the plates sprung as the bolts were loosened. I can get all of the bolts back in but in some cases the plates have to flex 1/4" to mate up to the angles.

So put the mounts on the motors and hang them in place. Then start swapping angles around, maybe even plates from 1 engine to the other. You might stumble on the combo that works. Pretty much that or fill the holes and re-drill where the angles wanna be. Unless the angles were pre-drilled in a jig, they are all gonna be different.

If the engine mounts are offshore style (most are) you have very little adjustment if any, that needs set once when the boat is built or re rigged from restoration, at that point it should not ever change.

With my offshore mounts I can move up and down maybe 1/4" at most, my drives slide right on..

[QUOTE=Full Force;4563679]




























at that point it should not ever change.


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I feel this is a very common misconception. even with alpha-bravo adjustable mounts. boats don't need realigned cuz the engine or drive was pulled and reinstalled. it needs realigned cuz it is made of fiberglass and wood, and some idiot (all of us) started putting between 250 and 750 ft lbs of torque on the points where those mounts attach to the boat. along with 750 lbs of weight AND they started splashing a bunch of water in there. ...AND THEN they start launching the boat off the top of every wave they can find...and all of this is going on while the prop(s) hanging below the transom are pushing in on the bottom and pulling out on the top of the transom assy like they are trying to tear it off the back of the boat. there is no way the transom and mount points on the stringers are gonna stay in the same place forever.

OUTONSAFARI

Actually if the plate does not fit flush both front and rear mounts have to be moved. You can't raise the front mounts or lower them and get the plate to align because now the shaft will no longer go in. First you align the engine with the shaft so that it goes in and out with two fingers and then you see if the plate fits flush. If it does you are golden. if it doesn't then you need to start making small adjustments to the rear mount and larger ones to the front.
I have added shims and large plates to lock down my rear mounts so that there is no motion available.
Since I started doing this I have not lost a single coupler with way more HP than they were rated for.

Setting alignment can be very tricky. I have aligned engines with the offshore style mount as well as stock Mercury adjustable mounts.

Either way you will absolutely need a good alignment tool. Grease the alignment tool so you can see the spline contact when you remove (just remove very carefully so you dont wipe off the grease). I also go by the rule-of-thumb that alignment is not good enough until you can remove the tool with 2 fingers and very light pressure. If you have to use a closed fist to remove the tool it is not aligned.

One other thing - the stop on the fatter part of the shaft is supposed to hit the gimbal bearing. When I do an alignment I insert the shaft part way and move the shaft in a circular motion to pivot the gimbal bearing in it's mount. I then center the shaft and give the bearing a little thump with the shaft.

Anyone know the diameter of the transmission end of the alignment shaft? I think I have the aluminum plate that goes on the helmet, I also have a shaft but it's not fitting in the transmission well. I may have to make a shaft or an adapter. This is the speed master 3/4/5 application.

you may be able to measure diameter on the low side of the splines on the drive

transmission end diameter is just under 1-1/8", 1.110-1.115 should do it