pump shimming problems

[steve-uk]

ok so i read the "how to shim thread" in the faq section

i just bolted up my pump and the drive shaft is sitting up towards the right of the opening (as you look at it from the pole)

so its clear your not supposed to shim the front end of the pump (has the dowels in so wouldnt be possible)

but if i shim the rear two this will have the affect of raising the shaft even further

photo attached, angle of phot isnt great, but its def not near the centre

advise appreciated

 

[SJBrit]

Are you sure you can't shim the front? It won't take much of a shim to move that little bit - surely the dowel will still engage? As for left/right. I would think there is enough slop in the pump mounting holes to loosen it and move it over. I guess you'll have to mark the correct position so you know hot to get it back in (I would also guess that with the midshaft in there it will self-align left to right)

 

[steve-uk]

reading this thread it says not to shim the front

http://www.x-h2o.com/threads/51928

i can almost force it over with the midshaft but thats not a good solution

 

[SJBrit]

Hmmm.... interesting. Surely it's bad to have the shaft too high like that though - I shall read people's responses with great interest since I'm about to go through the same thing.

 

[steve-uk]

in fact i cant twist the pump either on the bolts for left to right cos of the dowels...

 

[Waternut]

I believe everyone says not to shim the pump because they're working with a stock hull. I would think if you have an aftermarket hull and the pump isn't lining up perfectly, it would only make sense to shim the front.

You may want to try pulling those pins in the front mounts on the pump and see if it makes a difference. Maybe they aren't seating just right and causing the problem you're seeing.

 

[Matt_E]

How is shimming the front going to make any difference in left/right alignment?

Maybe it's a bad picture, but the left/right seems to be a far greater issue than the up/down.

 

[steve-uk]

its a wcf hull

i think the left to right alignment is more my issue than the vertical, means the mid shaft housing is out by enough for it to cause coupler alignment issues

matt i think if the theory is if the pump is shimmed at the front closest to the pump shoe, so it should bring the drive shaft down, i just tried it and i would have to put a pretty sizeable shim in there

does anyone else remove those dowels

 

[Waternut]

The next question I'm compelled to ask is... Is the hole centered about the midshaft bolts? The hole could be just cut for clearance only and not necessarily centered perfectly for alignment purposes. Try sliding the midshaft over the driveshaft and see how far the bolt holes are off. Remember, since the midshaft spins, you need to check all three holes and get the best fit before figuring how bad it's misaligned.

 

[Matt_E]

matt i think if the theory is if the pump is shimmed at the front closest to the pump shoe, so it should bring the drive shaft down, i just tried it and i would have to put a pretty sizeable shim in there

I understand that - but it's not going to help your left/right alignment.

 

[Waternut]

If you shim the right front corner only, the result will bring the driveshaft down and to the left slightly (I believe). I might be wrong on which way it goes but if you shim only one corner, it will move the alignment sideways some.

 

[steve-uk]

i took the dowels out.. problem solved it seems

 

[SJBrit]

The next question I'm compelled to ask is... Is the hole centered about the midshaft bolts? The hole could be just cut for clearance only and not necessarily centered perfectly for alignment purposes. Try sliding the midshaft over the driveshaft and see how far the bolt holes are off. Remember, since the midshaft spins, you need to check all three holes and get the best fit before figuring how bad it's misaligned.

That's true. the only real way to do the alignment is with the midshaft assembly in there and no midshaft.

 

[steve-uk]

not really, i could have used the mid shaft to pull the shaft across and i try that but it was so far out the bolts wouldnt line up.. i could have forced it... but i know that would cause other issues

looking at the hull looks like the previous owner must have removed those dowels too as the holes were full of silicone (which i picked out)

 

[Lucaumpits]

hey Steve
yes I did shim the front, also took out the pump pins
slide your midshaft on the driveshaft with out pushing or using any force, if the pump is tight and the pins of the midshaft housing line up with the fire wall holes you are good to go, shaft been off the center in the pipe donst mean anything,
let me know

not really, i could have used the mid shaft to pull the shaft across and i try that but it was so far out the bolts wouldnt line up.. i could have forced it... but i know that would cause other issues

looking at the hull looks like the previous owner must have removed those dowels too as the holes were full of silicone (which i picked out)

 

[augustaf]

Since you've deleted the front pins for lateral shaft alignment, you could shim the front pads too. However I find it much easier to remove (file off with a coarse bast*rd file) some of the metal off the nozzle pads (shim area). I just did that for an '09 hull that had the shaft actually touching the top of the hole when I installed a 61X nozzle! Took off .035" ( about 0.9 mm) centered the shaft perfectly. It's difficult to align everything perfectly when laying up a hull, some misalignment is to be expected with aftermarket hulls.

 

[Crab]

I use a big pry bar and make it go where I want it....lol.

 

[steve-uk]

hey Steve
yes I did shim the front, also took out the pump pins
slide your midshaft on the driveshaft with out pushing or using any force, if the pump is tight and the pins of the midshaft housing line up with the fire wall holes you are good to go, shaft been off the center in the pipe donst mean anything,
let me know

thanks man... i sorta thought you must of as i was getting the silicone out...

all seems to line up pretty good right now, with the lateral movement sorted out the vertical doesnt seem as bad

do you know what size shims you used? it looks pretty close without them

 

[kevbo]

Some shimming headaches can be helped by loosening the four long pump bolts so the nozzle can float where it needs to be. Yamahas driveshaft is not at all critical as long as it is close. Spend more time shimming the engine, thats the real spline killer.

 

[junkyardj]

steve i have a bunch of different pump shims i can bring by for you