thompsondockside.com

I have a 55 Offshore and I am looking for the right size engine. I have a nice 65 Evinrude 33 hp Skitwin, and a 60 40 hp Lark that needs a little work. I am afraid that the 33 will be too under powered for this boat with a family of four. I am looking at a 61 Johnson 50 hp. I know these engines like fuel. Am I better off fixing the 40 or getting a 50 hp?

If this is a 1955 Thompson Bros. Boat Mfg. Co. Off-Shore, she should be right at 18 foot centerline length.

To my way of thinking, anything less than 75 HP would be too small. With 4 people and a load of picnic supplies and fuel tanks could you even get her up on plane with a 40 or 50 HP?

I had a 110 HP on my '57 Sea Lancer with 16'-7" centerline length. She now has 70 HP (2 motors).

Andreas

Thanks. That 1961 Johnson I mention was said to be a 50 but all I can find listed for a 61 v4 is a 75HP. I am going to look at it this week. Larry

OMC's biggest outboard in 1958 and 1959 was 50 HP. The "Fat Fifty" was its moniker! In 1960 they went up to 75 HP and dropped the 50 HP. Their next biggest was 90 HP about 1964 or 1965. So 75 HP was the biggest they had from 1960 to circa 1964.

www.old-omc.de has many of the old Johnson and Evinrude outboard motor brochures posted on line.

Mercury had 80 HP in 1960 and 100 HP in 1962. 110 HP was introduced in 1966. They were always ahead of OMC in the HP race.

Andreas

In 1955, the biggest Johnson or Evinrude was a 25 hp, Mercury may of had a 40Hp.

I would find an old Thompson catalog and look and see how the boat was photographed. Bbest guess single 25hp Johnson or Evinrude, but could be twin set up. Does the transon show that single or twin engines were used?

A 1958 or 59 V4 50 was not a fast engine, but the gear case was designed for low speed thrust. Would probably do just fine, if you could afford the gas. A 1960 40hp might be just as fast but slower getting to speed.

My 1960 16' 202 with 1960 40hp plans easily and tops at 28 with one and 23 or 24 with 5 on board. Never a question about planning.

No doubt a v4 75 would be the best, but they were not available till 1960, most of these boats when purchased we with a sinlge 25 or may twin 25's.

Thanks for the information. The transom does look like it might have had twins. Don't you think that twin 35's would burn more fuel than a 59 50 hp?

Larry

Larry.. I wish I had twins on my Seacoaster... the 75 (1961) does a great job, but I would like the security of two engines, so if you have the option, I would go with twins.

Although I have never had an emgine problem other than running rich, or losing prime, it is a 50 yr old engine... with old wiring and so forth.

I believe that twins, even if lower combined horsepower, would be best.. I don't know the weight of the 25's or 35's, but if it is less than 242lbs, that would be a plus also.. I am a bit paranoid of that giant engine hanging off the transom..

John.