1982 Seaswirl 120 OMC Stringer IO

2024Seahawk

Recruit
Joined
May 8, 2023
Messages
5
So I have an '82 Seaswirl IO 120 with a stringer OMC lower unit. Have replaced the water pump 3 times in the lower unit in 2 years and they keep disintegrating!
Is it possible that the exhaust manifold is cracked inside and allowing exhaust to get into the cooling system and "melt" or destroy the rubber impeller?
I used all the right sealers and new parts.
Also, does anyone have a picture on the hoses that got to the thermostat housing? Might have crossed those at one time too.
Thanks.
 

Scott Danforth

Grumpy Vintage Moderator still playing with boats
Staff member
Joined
Jul 23, 2011
Messages
50,224
what brand are you buying? Sierra or GLM?

Generally lack of cooling water flow is what causes the impeller to destroy itself, or the kits you are buying are old. Rubber has a calendar life that starts the day its molded, not when its used.
 

2024Seahawk

Recruit
Joined
May 8, 2023
Messages
5
Looking for help on the water pump impeller on the OMC 400 I have on my 1982 Seaswirl 4 cylinder.
I've had to replace the impeller 3 times since moving to Texas and never since my purchase in 1984 in Washington State. Moved to Texas 8 years ago. I'm using the O.E. sealers that they recommend for the job too.
Wondering if exhaust gases getting into the cooling system could cause the impeller to disintegrate as that's what keeps happening after only a couple of times on the water. Then I usually let it set sometime for weeks before using it again. And the impeller is toast again with no water circulation. Maybe the Texas sun is melting it to the housing? Blown head gasket? However, the engine runs without a engine miss.
Absolutely any help would be appreciated, getting tired of replacing those impellers.
 

southkogs

Moderator
Staff member
Joined
Jul 7, 2010
Messages
14,968
Have you been greasing the swivel on the outdrive? Grease zerk is on the front of the intermediate housing behind the red plastic "bolt."

If that's not greased, exhaust gas can get in there.
 
Top