shimming engine and pump. How important is it?

[LOWDOWN]

i shim my pump to get it real straight. my motor doesnt use as many shims when the driveshaft is straight.

Does this mean you should shim your pump before the engine?

Thanks,

jEFF

 

[yigaljet]

you should align the pump first then the short shaft assembly,
remember ,a misalign shaft or coupler can cause heat ,the coupler will get hot and finally a crank seal failure

 

[Big Kahuna]

this is a little more confusing than just putting the pump in without the midshaft installed and making sure the shaft is centered in the hole in the hull.


my question is, how important is that pin on the front tab of the pump that goes into the hull? my pin is missing on my rn pump. i noticed that my fx-1 never had one to begin with.

how do you know the hole in the bulkhead is actually centered with the bolt holes for the midshaft housing? Do it right or take the chance..... I learned the hard way twice.......

 

[stand'em up]

I would highly recommend you align your pump w/ the inter shaft assy removed. Just put the two front pump bolts in and then shim accordingly to get the shaft in the very center of the hole. There may be a better way, but this has worked well for me. Test the fit by sliding the inter shaft assy on to the bulkhead and see if there is any binding when the holes line up.

fyi - the two front pump bolts never get shims, only the rear pump bolts do.

When you say centered in the hole, is that just up and down, or left to right as well?

 

[Waternut]

Are you guys just eyeballing the alignment? The shims on my pump look like they might total up to be 0.010"-0.020". I can't see how even 30-40 thousandths could really have an adverse effect. Now I can see 0.100" being a big deal but that's about it.

 

[QuickMick]

This is some good information.
I have a question, how hard is it to replace the bearing on the mid shaft??
The bearing that looks to be in a carrior (surrounded by the rubber coller)
yea that one that bolts to your bulkhead.

Mine turns smooth but has rust on the outside.

McMaster Carr part #??????

 

[tipafew]

how do you know the hole in the bulkhead is actually centered with the bolt holes for the midshaft housing? Do it right or take the chance..... I learned the hard way twice.......

That's a good question. I have always done it the same way as Yamaslut.