Topic: 1959 Johnson 18 hp. – Antique Outboard Motor Club,Inc

This topic has 7 replies, 6 voices, and was last updated 4 months, 1 week ago by fleetwin.

Viewing 8 posts - 1 through 8 (of 8 total)

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July 16, 2024 at 8:25 am #289190
The Boat House
Participant
Friend is wanting to know what this water passage is for and if it matters which way this plate faces? Thank you – Tubs
July 16, 2024 at 9:37 am #289192
labrador-guy
Participant
US Member
Tubs those holes go towards the front of the motor. I could only guess that maybe it helps let the water drain out when the motor is tilted up. I have seen many turned the other way. I makes no difference as far as pumping water goes. You need to get the water out of the pump area before freeze up time. JMHO

dale

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The Boat House
July 16, 2024 at 10:13 am #289193
crosbyman
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Canada Member - 2 Years
diagram does show the holes pointing to the front

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July 16, 2024 at 11:04 am #289194
nj-boatbuilder57
Participant
Service bulletin indicates that the holes face forward. Additionally, the bulletin states that plate must be removed when running with a test wheel.

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seakaye12, labrador-guy, The Boat House, Fastwin18
July 16, 2024 at 12:43 pm #289198
The Boat House
Participant
Well that should tell him what he is wanting to know. I’ll pass it on. Thanks so much. Tubs

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labrador-guy
July 16, 2024 at 5:05 pm #289206
labrador-guy
Participant
US Member
I would like to know what the engineers have to say about that cover. The early 50’s had no holes then around 53 they had two holes one on the top and one on the bottom. 56 they have three on the bottom. Maybe some kind of experimenting going on!

dale

Is there beer in Wisconsin!
July 17, 2024 at 11:03 am #289219
aquasonic
Participant
US Member
Somewhere, I recall reading that the holes in the bypass cover also assist in supplying cooling water when the motor is in reverse.
July 18, 2024 at 6:26 pm #289249
fleetwin
Participant
US Member - 2 Years
This is a great topic, question indeed. I have seen these covers installed both ways. I have seen them installed with the cupped inlets facing rearwards which never made sense. But, now that everyone mentions it, the lower pickup is doing most of the work at higher RPMs in forward. But, in reverse, the water is being pulled away from the lower water inlet, so the reverse cupped intake cover up above seems to make a bit more sense now..
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