inboard strut alignment

[salty87]

23' ski boat

i've just finished new stringers and deck. engine has been rebuilt by reputable shop. she's all back together. alignment is ugly though. the shaft almost hits the shaft log to 1 side with the couplers disconnected. i don't think there's enough room on the mounting trunnions to move the engine over that far. even if i did, the shaft is too close to the hull.

when aligning the shaft, how much are you allowed to move it by hand? it has to be lifted a bit to correct for sagging. i've been using a screwdriver to shim it into place. pulling to the side lines it up in the log better and gets me real close to tolerances. just to see, i fired her up and after soaking the cutlass bearing i put her in gear. not good enough to even try on the water.

does this mean the strut is out of alignment?

 

[Don S]

Re: inboard strut alignment

Struts can be bent, and straightened. I've done a couple this year that had bent shafts and struts. Check both or you NEVER will get the alignment right.
Most prop shops can check and repair struts, shafts are replaced if bent, along with the coupler on the tranny end of the shaft.
I usually dry fit the strut and shaft and see that they center in the packing gland, and centered in the strut bearing. Make sure the rubber on the bearing is equal all around on both ends of the bearing.
It's time consuming, but it sure makes a difference in how they run.

 

[salty87]

Re: inboard strut alignment

don,

have you ever straightened one while still attached to the hull?...with the old shaft still in the strut? yuk yuk...the coupler and shaft don't want to cooperate, they're locked together.

prop shop said no problem, just drop the strut and swing it by. i guess if i did that i might be able to leave the coupler/shaft alone. nah, rudder will probably mess that up.

...not looking forward to taking the strut off

 

[Don S]

Re: inboard strut alignment

the coupler and shaft don't want to cooperate, they're locked together.

That happens quite often. There are pullers, but usually on ski boats there isn't enough room to get the coupler in there. If the shaft is bent (have you checked with a dial indicator?) just cut the end of the shaft off at the coupler. Send the shaft and the coupler to the prop shop and they will make a new shaft and install a new coupler and face it true.
You can also try putting a spacer between the coupler halves ring on the shaft and use the coupler bolts to pull on the coupler without the shaft moving. It works if it's not frozen too bad. You can also pull the engine and get it out of the way. Ususally the fastest way to do the job.

Forget even trying to straighten the strut with the shaft in it. You have to overbend them to allow for spring back, and you probably still need to replace the cutlass bearing anyway.

 

[salty87]

Re: inboard strut alignment

You can also pull the engine and get it out of the way. Ususally the fastest way to do the job.

Forget even trying to straighten the strut with the shaft in it. You have to overbend them to allow for spring back, and you probably still need to replace the cutlass bearing anyway.

and i just put the engine back in a few weeks ago. ugh, it's staying put. lol

i like the idea of cutting the coupler off.

i'm going to get them apart today and drop the strut. let the prop shop get to the bottom of it all.

thanks for the words of wisdom

 

[salty87]

Re: inboard strut alignment

got the strut off, cutlass bearings are bad.

coupler is still seized to the shaft, still in the boat. i'd like to take them all to the prop shop but that's not looking too possible. i'm going to call the prop shop in the morning and see if they can help with the coupler...they made the friggin' thing. maybe they can cut it off and give me a deal on a new one. or it stays and i hope it's ok.

 

[Don S]

Re: inboard strut alignment

IF that strut is bent, you can bet money the shaft is too.

 

[salty87]

Re: inboard strut alignment

just cut the end of the shaft off at the coupler.

with a torch?...

it won't budge. i secured a nice fat bolt to the end of the shaft and tightened down on the bolts. heated the coupler, iced the shaft...nothing. i heard a few noises but don't think i got any movement.

the strut's off and it's not too straight. the bearings are toast too. old rotten stringers must have been able to absorb it. there wasn't any vibration before.

i have an old shaft i can take in to order a new one but i need to get the old one out eventually.

what would a reasonable charge be?? what would cut it?? 1" shaft

thanks again

 

[Don S]

Re: inboard strut alignment

what would a reasonable charge be??

Depends on type of coupler access to the job, and the tools the shop has.
That's a time and material job.

what would cut it?? 1" shaft

Hack saw and some patience.

 

[salty87]

Re: inboard strut alignment

i went with the sawzall and a fat pack of blades. finally got it.

prop shop has it all.

here's the strut

 

[Don S]

Re: inboard strut alignment

Looks bent and twisted a little to me.