Re: 1956 Johnson 10HO QD 19 exhaust housing temp

[Don]

Well yes, this hsg is a one year only piece….But, this is only because of the lower motor cover change. 1958 was the only year of the 10hp/small g/c and exhaust hsg that used the aluminum clam shell hoods, later models all used the one piece lower motor cover and fiberglass hood. The change in the exhaust hsg is the mounting holes/flanges on top of the hsg for the different cover/hood design that occurred in 1959.
And yes, the seller is incorrect, that is surely not a 1968 10hp, no such thing.
Were there other problems with the 1958 exhaust hsg design? Not to my knowledge, but maybe Garry/Frank might know more. I do remember one other fellow having a problem similar to yours, but I think it was on a 10hp that was a 59 or newer model. I’m pretty sure the fix was adding a very small bleed hole at the top of the inlet water tube passage to spray the upper hsg with cool water….
This is an interesting topic for sure, would love to find the actual fault with the hsg…I will have to have another look at the hsg I have….
I would speak with the fellow with the Johnson hsg, I’m betting he is willing to accept much less, his asking price is ridiculous, he is just shooting for the moon.