Re: 90 hp inline6 H2o pump help
heating the prop shaft? Never heard of that one... lol.. this is an easy process. ( i have a 115 inline).
Step 1: put the lower in NEUTRAL... do not put it in forward.. i have no idea where people get that. The reason for neutral is that it is the only position where the shift shaft is locked in place, well i suppose reverse is as well, but use neutral.
Step 2: loosen nuts and bolts, there should be 3 nuts on the back side of the lower, two nuts on the bottom of the cavitation plate, and one bold that is accessed when you take off the trim tab.
Step 3, remove lower (duh) i use a floor jack with a rubber pad on it if i am doing this alone.
step 4: the tiny shaft in the back of the lower is the shift shaft, it will have a black plastic cam on it.. DO NOT TOUCH THE CAM OR SHAFT.. if that cam falls off.. well... just dont let it happen, its a large pain in the rear.
step 5: grease the main driveshaft ( i normally use lower unit lube)
Step 6: remove bolts that hold the plastic upper pump houseing in place and remove the housing (if the housing and gaskets are in good shape, you can reuse them, if not, replace both.
Step 7: slide the old impeller off the shaft.
Note: there is a small key that holds the impeller in place on the shaft.. don't lose it.
step 8: slide new impeller onto shaft, replace the gaskets, then replace the upper housing, it also makes it more easy to put the new impeller on if you grease the inside surface of the housing.
IMPORTANT: while forcing the the upper housing back down, turn the drive shaft CLOCKWISE, this will put the right orientation and spin on the impeller, as well as make it possible to get the housing back over the new impeller.
Step 9: put the lower back on the boat... now this is a pain for the first timer, both shafts have to line up, a small screwdriver makes it easier to get the shift shaft to line up.
Step 10: NEVER EVER EVER run the motor without water getting to the pump EVER.. an impeller will be toast in the matter of seconds...
Store time:
I had a BRAND NEW impeller on my 115 last summer. I have this habbit that i got from my grandfather that i ALWAYS run my boat motor before heading out to the lake, just to make sure that it will start when i get to the ramp: i think of it as a courtesy to others at the ramp. Well this particular afternoon i was in a big hurry (i do not recall why) so i hooked up the muffs, turned on the water, started the engine and ran inside to change clothes. I came out a few minutes later to find NO water coming out of the tell-tale or prop. What happened? Well.. this is when i used the stock power trim on the motor (has since been replaced with a cmc unit) and this power trim, being 30 years old sagged... Well i trimmed up the motor a little, put on the muffs and left.. the motor sagged... the muffs hit the transom, and pushed them forward passed the water pickup holes on the lower. Moral of the Story: NEVER get in a hurry while working on a boat, and NEVER leave a running boat unintended. And you thought you had a long post, HA!
