73 Evinrude 9.5

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Rebelwork

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Nov 11, 2020
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Odessa,Mo
Owner said motor ran 10 years ago before shutting down.. Have things to do before next year to run it. I would like to put on the boat to see how it sits in the water. I have it currently in the garage. Looks like he had a cheap transom saver in the boat whenpurchased. Should I buy a new one at bass pro for around $30 or do I need one on a small motor?
 
Pretty light motor. Depends on how flimsy your transom is and how rough the commute to the lake is. I just put a 1" ratchet strap around my motor to keep it from bouncing but a transom saver never hurt anything!

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I wouldn't think so. If the motor is safe in normal operating position while being trailered you are good in that aspect. If the motor is fully lowered or just slightly trimmed up you shouldn't have any issues with bouncing and stressing the transom either. Now if the transom integrity is questionable that may change things, however, I'm of the belief that the stress on a transom from the outboard underway is going to be greater than that from trailering forces.... so if it's questionable to trailer I wouldn't feel safe using it like that on the water either.
 
wmk0002 said:
I'm of the belief that the stress on a transom from the outboard underway is going to be greater than that from trailering forces ...
That's too funny, as I have the exact opposite opinion ... where I see guys trailering boats on hard concrete doing 75MPH blowing past me on the highway! I'd rather hit a wave going 20MPH in 'softer' water that gives some ...

But regardless, I think we're both right in our assumptions! I too wouldn't bother with a transom saver if it was sound. I usually trailer in the shallow-water drive position just to keep the skeg up some.
 
DaleH said:
wmk0002 said:
I'm of the belief that the stress on a transom from the outboard underway is going to be greater than that from trailering forces ...
That's too funny, as I have the exact opposite opinion ... where I see guys trailering boats on hard concrete doing 75MPH blowing past me on the highway! I'd rather hit a wave going 20MPH in 'softer' water that gives some ...

But regardless, I think we're both right in our assumptions! I too wouldn't bother with a transom saver if it was sound. I usually trailer in the shallow-water drive position just to keep the skeg up some.

Haha. It's definitely different types of loads for sure plus things like engine hp/vs weight. Thrust would be a pretty steady static load while trailering would be more dynamic and introduce fatigue. Do you happen to know anywhere I could find documented thrust numbers for various hp outboards? I've always told my myself if I had some good loads to work off I would try to scratch some math out on the subject. By day, I do aerospace structural analysis but I always have loads to work off of thanks to the loads teams lol. I did some stuff a couple years ago when I was messing around with a jackplate design but I didn't have any idea how to load it so I just said "1 lbf" so I could easily scale my results.
 
wmk0002 said:
Do you happen to know anywhere I could find documented thrust numbers for various hp outboards?
Just check the websites of the various engine makes. They're pretty illuminating, like demonstating as a general rule of thumb that a 4-stroke OB needs about 20 to 25% more displacement than a 2-stroke OB to produce a similar power curve.

Personally I LOVE this torque curve of the Evinrude direct injector 2-stroke and remain PISSED that the 'bean counters' pulled the plug on them!
E-Tec.jpg
 
It's Sept and I'm going to pick up a gas tank and line this month. The guy I bought it from was honest and said it worked when he shut it down 10 years ago. I sprayed sea foam in to make sure the Pistons were free before pulling. I saw spark on oneit on but couldn't get it on the second. It was suggested to try and start the engine without any work to see what it might and might not do.

The manual is 200 pages long. I'm trying to decide to download and print or just buy itt used on Ebay...

I figure I better fix everything up first best I can. No point putting fancy wheels on a rusted hotrod....
 
Guys.....There are no dynamic thrust loads on outboards anywhere, nor are there numbers on what kind of load a transom will take.
Unless you trailer on a road from Hell you probably do not need one.
When we used the Dyno boat more at OMC those numbers were taken and recorded but never published.
Think about this. You are running wide open throttle and hit a stump. What happens to your engine? It slams up hard enough to sometimes break the mount brackets and then back down under the thrust and acceleration of being at WOT and slams back into your transom. Usually the engine breaks before the transom gives up. Just the simple thrust loads of a strong engine probably stress the transom more than a trip to the ramp.
Common sense prevails here and if your transom is weak and you are trying to get the rest of the season out of it? Sure.

When I worked for OMC at the Stuart Fl. Test Center I did some destructive testing. It was fun! We did log jumps with all of our product. Never broke a transom on an outboard or failed the stringers on a Stern Drive. We did this in order to design in a sequential failure of parts. Both the outboards and the drives were loosely tied to the boat for recovery and analysis. I drove from inside a a reinforced steel fence and have had both V6 outboards come in the boat with me as well as a complete drive from a Stern Drive after hitting the log at high speed. The drive hit the fence hard enough that we modified the process on drives to just allow the drive to sink but had a line and float attached to it that payed out on impact. We then pulled it up off the bottom for inspection.
 
There recommending marine gear oil or 80-90 gear oil from parts store. Recommendation?

It's also been suggested to hook up the proper fuel and see if it will even crank. I shot seafoam n the Pistons earlier in the season to make sure they were free. ...
 
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