I have an '81 Glastron with a Mecruiser 228. I need to replace the
impeller in the outdrive. What outdrive should be on this boat? Are
all mercruiser impellers the same? Is the disassembly/replacement
procedure the same on all? Does someone have the step-by-step to
replace this part? Maybe an exploded view schematic of this outdrive?

Thanks in advance for whatever you can provide,
Chris

"Chris" wrote
What outdrive should be on this boat?

Maybe this will get you started in the right direction:
http://www.mercstuff.com/drive_id.htm
There are some exploded views and procedures on the site as well.
If you can locate the serial number on your drive, it would be a very handy
thing to have when ordering parts.

Thank you so much. It is clear to me now after the great pictures on
the site that I have a "pre-alpha" unit. I will check the serial
number to verify. Is there any reason to take off the entire stern
drive to replace the impeller or should I just take of the lower unit?
The only reason that I would take off the whole thing would be to
grease the U-joint. I am of two minds on whether I need to worry
about this. First, I have seen many posts where it is recommended to
grease the U-joints every year. This boat is new to me so I have no
idea when it has been done last. On the other hand, once a year seems
like overkill. How often does anybody grease the U-joints on their
car? I don't think my truck even has zerk fittings on the U-joints.
I only use the boat about 20-40 hours a year at the most. I am also
wary of openning a can of worms. What does MerCruiser say about
U-joint lubrication?

Chris

"Chris" wrote
Is there any reason to take off the entire stern
drive to replace the impeller or should I just take of the lower unit?

You can replace your impeller with the lower unit removed and the upper
still on the boat. I just greased my u-joints over the winter while
replacing some other stuff in that area. I'm pretty sure the last time they
were greased was 27 years ago when my drive was manufactured. (I got it
second hand two years ago and the previous owner doesn't appear to have been
a big fan of preventive maintenance.) I don't have my manual handy, but I
suspect the recommended interval is a little shorter than that.

Taking off the whole unit isn't that much harder than dropping the lower.
Ive done it myself. With another set of hands it's much easier. It cost
less than $15 for the bell housing gasket kit.

Even if the unit doesn't need u-joint lubrication, removing the drive
provides a good indicator on the condition of the driveshaft, gimbal
bearing, and the driveshaft bellows. If you see rust on the drivshaft or
Gimbal, its a good indication that one if not all three need to be
replaced in the near future.

Bob Dimond


In article ,
(Chris) wrote:

Thank you so much. It is clear to me now after the great pictures on
the site that I have a "pre-alpha" unit. I will check the serial
number to verify. Is there any reason to take off the entire stern
drive to replace the impeller or should I just take of the lower unit?
The only reason that I would take off the whole thing would be to
grease the U-joint. I am of two minds on whether I need to worry
about this. First, I have seen many posts where it is recommended to
grease the U-joints every year. This boat is new to me so I have no
idea when it has been done last. On the other hand, once a year seems
like overkill. How often does anybody grease the U-joints on their
car? I don't think my truck even has zerk fittings on the U-joints.
I only use the boat about 20-40 hours a year at the most. I am also
wary of openning a can of worms. What does MerCruiser say about
U-joint lubrication?

Chris

The drive is known as a pre alpha. It shares the vast majority of
components with the alpha. Most water pump kits have gaskets for alpha
and pre-alphas.

Bob Dimond


In article ,
(Chris) wrote:

I have an '81 Glastron with a Mecruiser 228. I need to replace the
impeller in the outdrive. What outdrive should be on this boat? Are
all mercruiser impellers the same? Is the disassembly/replacement
procedure the same on all? Does someone have the step-by-step to
replace this part? Maybe an exploded view schematic of this outdrive?

Thanks in advance for whatever you can provide,
Chris