Twin 70hp yamahas on a 22ft cruiser

rock knocker

New member
I am looking at a 1989 22ft cruiser and he repowered with 2014 twin 70 yamahas. Anyone know if these are too heavy or anyone running them. He wanted to be able to run on 1 at a time is the reason for the upgrade. Doesnt look like they are too much heavier than the 50s. Thanks for any input.
 
I believe that the 50, 60 and 70 Yami's are all the same block, so same weight. They are heavier than the 40's and that is why I would have to do some serious considering before repowering with 50 Yamis. WOW, twin 70's. That is some get up and go power. Unless running (very) heavy, I would think that would get up onto the edge of scary at the top end. It should certainly plane on one of those running as a single.

Harvey
SleepyC :moon

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What would an insurance company do when looking for a loophole to avoid a payout on a claim? Oh, you have a combined hp of a 140. The manufacturer upper limit on hp is much less for a 22. Claim denied. So beware.
Martin.
 
Bridma has a good grip on the possible problems.

When I purchased my 1983 22' Angler new at the factory they told me not to install a 115 hp engine that I already had. Boat rated for 90hp max. I did it anyway and the result was....at approx. 30 mph the hull took a very fast port side roll which scared hell out of me and I think stained the skivies. It was the result of over torque on the hull. Pulling the throttle back caused it to upright immediately. So I did it again very slowly. Same result. I never tried it again and ran that engine for 15 yrs w/o any problem.
Your twin setup may be able to resist the torque.
Be carefull.
Jack in Alaska
 
The boat was designed for one lightweight two stroke 70 hp engine available at the time. This boat will be an ill handling pig IMO. Keep looking.
 
I too like the idea of being able to plane on one motor if necessary & the power to put the boat where I want for safety if caught in big seas. My twin Honda 40’s are fine most of the time, especially where we choose to do a high percentage of our cruising at displacement speed, but on Yellowstone Lake the 80 hp turns into 61 & when really heavy in SE Alaska there have definitely been times 140 hp would have been welcomed. Weight wise those combined 70’s weigh 78 lbs more than my Honda’s & compared to the extra 500 lbs, I’ve carried many times in the cockpit, the addition doesn’t amount to much, especially with the extra hp. 78 lbs is only 12 gal of gas & we’ve many times left port with an extra 50 gal on top of our standard 46 gal. Even when extremely heavily loaded our CD22 has handled well in many adverse conditions. Though, I agree with less weight more nimble.

The insurance thing is not a big deal to me either or the possible over torquing as Jack mentioned. I think the later model CD22’s bottom shape would handle the power much better if top speed was kept reasonable. What would concern me about the 70’s is there performance & fuel milage. I don’t know if it was this boat, but I do remember a post where their use was being considered & I wish the performance data had been shared.

I’m considering upgrading motors & the new 2019 Tohatsu 60 hp at only 4 lbs heavier per motor then my present Honda 40’s are high on my possible choice list.

Jay
 
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