Motor Alignment For RN

[Bruins]

Can any one tell me a good way to align a motor in a Roundnose? How important is it to align your motor? Can you eyeball it close or should you go further than that? Thanks in advance for the help.

 

[michael950]

If you do not properly align the motor you will break couplers, strip splines on the shaft, etc.

There is a thread in the FAQ and I know there is one on PWCT with the specs.

 

[Eric78]

What makes it alot easier is if you allign the pump first. You should only have to shim the back two pump bolts. You want to do this so you can get the driveshaft right in the middle otherwise it is usually towards the bottom. You need to take off the driveline coupler inside of the hull so you can see where the driveshaft is at.

Once you have done that it makes shimming the motor mounts much quicker cuz you don't have to compensate for the driveshaft being pointed downward. It is perfectly centered so that makes things that much easier.:biggthumpup:

 

[Mouthfulloflake]

This is something I have not heard of Eric, its not specific to RN hulls is it?
I have only installed, and shimmed engines/pumps into square nose hulls
could you elaborate?

 

[ski4]

What makes it alot easier is if you allign the pump first. You should only have to shim the back two pump bolts. You want to do this so you can get the driveshaft right in the middle otherwise it is usually towards the bottom. You need to take off the driveline coupler inside of the hull so you can see where the driveshaft is at.

Once you have done that it makes shimming the motor mounts much quicker cuz you don't have to compensate for the driveshaft being pointed downward. It is perfectly centered so that makes things that much easier.:biggthumpup:

slf i think explained this way to me as well and it made m life much easier

 

[Mouthfulloflake]

IM not clear on that.

shim the rear of the pump down to center the drive shaft in what?
Im guessing the thru hull? or the intermediate housing?

IM dumb.

can somebody draw me a picture?

 

[#ZERO]

Start by taking the engine bolts out and removing all the shims. Mark the engine shim packs prior to the mounting bolt removal for ease of reassembly and coupling alignment. Keep each shim in its same location for now. Then remove the rubber damper between the couplers. Get yourself a small straight edge about six inches long and check the clearance around the couplings. You should measure all of your shims with a thickness gauge and mark them accordingly. Then start raising the engine one shim at a time until the couplers are lined up all the way around within a spec of 0 to 1mm. Once you have obtained perfect engine alignment move the engine back and reinstall the rubber damper. Push the engine back into place with a distance of 2mm to 4mm between the couplers. Then use large hose clamp or band type piston ring compressor and tight down around the couplers with the shims in there correct locations torque down all your engine bolts.

 

[Mouthfulloflake]

thats basically how I do it now.

I was asking about the procedure of aligning the pump first?

Start by taking the engine bolts out and removing all the shims. Mark the engine shim packs prior to the mounting bolt removal for ease of reassembly and coupling alignment. Keep each shim in its same location for now. Then remove the rubber damper between the couplers. Get yourself a small straight edge about six inches long and check the clearance around the couplings. You should measure all of your shims with a thickness gauge and mark them accordingly. Then start raising the engine one shim at a time until the couplers are lined up all the way around within a spec of 0 to 1mm. Once you have obtained perfect engine alignment move the engine back and reinstall the rubber damper. Push the engine back into place with a distance of 2mm to 4mm between the couplers. Then use large hose clamp or band type piston ring compressor and tight down around the couplers with the shims in there correct locations torque down all your engine bolts.

 

[#ZERO]

thats basically how I do it now.

I was asking about the procedure of aligning the pump first?

The pump housing has stainless steel pins in the housing for alignment.

I have seen some with paper thin stainless steel shims for the height setting.

But why would this change?

Just reinstall the shims in there same location.

 

[Mouthfulloflake]

#0,

did you read the post below by Eric?

What makes it alot easier is if you allign the pump first. You should only have to shim the back two pump bolts. You want to do this so you can get the driveshaft right in the middle otherwise it is usually towards the bottom. You need to take off the driveline coupler inside of the hull so you can see where the driveshaft is at.

Once you have done that it makes shimming the motor mounts much quicker cuz you don't have to compensate for the driveshaft being pointed downward. It is perfectly centered so that makes things that much easier.:biggthumpup:

 

[#ZERO]

Yep :smile:

 

[Mouthfulloflake]

but your post says nothing about the questions I asked about aligning the pump as outlined as eric was talking about.

so is it a secret?

or since they have stainless pins to align them, youve never messed with it?

or you just cant tell me?

Or you dont want to talk about it?

or what?

Yep :smile:

 

[#ZERO]

Top Secret :sneaky: :sneaky: :sneaky:

Factory special tools needed; alignment rods, dial indicators, hull stand, jig fixture, laser plum line, shims, etc.

It may be something only the Yamaha factory knows; it's not in the manual?

 

[Mouthfulloflake]

I dont know manuel.

I do know a chick named julio though.

and I like tortas...

does that count?

 

[Eric78]

This is something I learned just this last past year. I was in Macau doing these jetski shows. We had brand new 06 SJs. Even when the SJ is brand new the driveline is not aligned all that well.

If you already have your engine out then take off the coupler(forget name) that is attached to the hull. Intermediate housing is the term I'm searching for I believe. It should be attached with four bolts if I remember right. Once you have done this look at the driveshaft. It will be towards the lower half of the hole. I believe it flexes some due to the weight. This is why shimming the pump is ideal. It will eliminate any extra driveline wear that you might get otherwise. You can shim the back two pump bolts until you get the driveshaft right in the middle so its not rubbing against anything.

The best reason to do it is once you have done that it makes shimming the motor mounts much much easier because the couplers will be more directly pointed at each other.

I don't know about you but I hate shimming the motor mounts. It's a pita. Try this out and I promise you won't have to use hardly as much engine shims to get it right.:arms:

 

[Mouthfulloflake]

Thank you Eric!

I noticed on BOTH of my old square noses, that both pumps were shimmed in the rear, I didnt know why until now.

both were set up in the early 90s by various 'race shops' around here, and were set up pretty well for the time period.

it all rings clear now.

:hail:

This is something I learned just this last past year. I was in Macau doing these jetski shows. We had brand new 06 SJs. Even when the SJ is brand new the driveline is not aligned all that well.

If you already have your engine out then take off the coupler(forget name) that is attached to the hull. Intermediate housing is the term I'm searching for I believe. It should be attached with four bolts if I remember right. Once you have done this look at the driveshaft. It will be towards the lower half of the hole. I believe it flexes some due to the weight. This is why shimming the pump is ideal. It will eliminate any extra driveline wear that you might get otherwise. You can shim the back two pump bolts until you get the driveshaft right in the middle so its not rubbing against anything.

The best reason to do it is once you have done that it makes shimming the motor mounts much much easier because the couplers will be more directly pointed at each other.

I don't know about you but I hate shimming the motor mounts. It's a pita. Try this out and I promise you won't have to use hardly as much engine shims to get it right.:arms:

 

[#ZERO]

Well it's nice to hear you guys are aligning your pump shafts correctly. :biggrin:

But the intermediate bearing housing has stainless steel guide pins and shims at the top for angle adjustments. Also the bearing housing is line with soft rubber for flexing and vibration problems. How do you know at the correct angle for your intermediate bearing housing? That's the part touching the engine coupler.

 

[D-Roc]

my hull has shim thickness written on the hull for the back pump bolts that you speak of. i believe they are on there from the factory. i used those numbers and then checked to ensure the drive shaft was indeed centered in the thur hull hole.

 

[Watty]

When I align the pump etc, I start by removing the pump and intermediate housing. Obviously at this time, the engine is already unbolted and moved forward.

Insert the pump into the back of the ski and bolt it up making sure the alignment pins sit in thier little holes on the hull. Bolt it all up and then grab your mid shaft housing. Slide it over the drive shaft and it should pretty much go right on and fall into it's holes on the firewall. If you have to lift the housing up or push it down with pressure, your pump isn't aligned properly.

You'll usually have to shim the rear bolts on the pump to raise the height of the shaft inside the hull. Once it all slides on and pops right into it's holes with no pressure, you're set....

Then, follow 0's instruction above, and bobs your uncle.