Banging evinrude

[zippermouthlake]

I have been working on a 1962 14ft runabout of manufacturers unknown for 2 winters. Mostly due to the cost. I finished it this spring and broke the bank on new steering, controls,tank, battery, hardware ect. My dad gave me a spare motor he had and I put it on today. I was drooling with anticipation this afternoon in the +37 degrees celcius heat. I got the 42 year old beauty to the lake and put her in. The first turn of the key and it purred. As we pulled out of the bay all seemed well. Then the curious bang. It almost felt like it popped out of gear for a split second. It would do that intermittantly at slow and fast speed. We checked the linkage and all seemed well. My dad says he thinks it was cavitation. I have read around your site and it seems cavitation is more constant not a sharp bang. I brought the boat home with great sadness as he thinks a longshaft would be better (which neither of us have nor can afford right now.) After pulling in the yard I noticed the new gas tank that I had bought (plastic marine type) had sunken in from not opening the vent screw. Please tell me that I should take the boat out again and that is what it was. Th motor is a 35hp evinrude with maybe 20hrs on it model E35ECSM if that maters. Sorry for the drawn out story but I couldn't help myself. Awesome site I will be back with everything my lack of boating and over-abundance of fishing knowledge has to offer. Cheers from the great white north- that is hotter than hell right now

 

[Bass Runner]

Re: Banging evinrude

Well take it back out if that tank had been a steel one you would have been dead in the water but because of the soft sides of the plastic tank it would give, this time remember to (OPEN THE VENT) Good luck and welcome to the forum. If you like old boats check the fins on mine at the url on bottom of page.

 

[zippermouthlake]

Re: Banging evinrude

I tried again withe the vent open and still bangs intermittantly. I was raeding other posts and is it possible that the prop slips for a split second or not? I kept the boat at a slow push and it seems that the motor kicks out at 25% power and above. The motor has been stored for an easy 8 years but like I said it has very minimal hours on it hours on it. HMMMMMMM

 

[Bass Runner]

Re: Banging evinrude

Have you changed tie oil in the lower unit? it sounds like it might be slipping out of gear check the cable and make sure it is pushing it all the way in gear, as far as the prop it won't slip and catch when they slip the rpm will go up and not stop. i think the problem is in the lower unit or the adjustment, what year is the motor

 

[Winger Ed.]

Re: Banging evinrude

this afternoon in the +37 degrees celcius heat. [/QB]

First off, you're going to have get away from that Metric 'stuff'. What the heck is Celcious anyway? Sort of reminds me of when the Doctor said I had a problem with my Addnoids.<br /><br />I didn't know what he was talking about. I went ahead and paid him anyway, but never understood what was wrong with me. I never did figure out if it was something genetic, airborn, or if I caught from a cheap hooker years ago when I was on Okinawa with the FMF while in the 1st Marine Air Wing. I think that was back when I got drunk one nite and humped a parrot. If ya ever see a crazy looking, skinny teenager that has green & orange hair, he might be my son. <br /><br /><br />Seriously:<br /><br /><br />Look at the back end of your boat. With the hull & engine you have, sight along the bottom of the hull. Determine if, and how much of the arc the propellor spins in is above or below the bottom of the hull.<br /><br /><br />If more than 90%---- I don't know how many upteen million millimeters that would be--- of the prop is below that sight line of the hull, you don't have a cavitation problem.<br /><br /><br />The more and more of the propeller arc that is above the bottom line of the hull, the more that cavitation is what's happening to you as your rpm goes up. (Especially if you have a rather high pitch prop) <br /><br />If that's the case, do what ya gotta do to lower the engine down into the water more.<br /><br /><br />If its a cable/linkage problem, usually holding the shift lever all the way down in the forward position will keep it from jumping out of forward gear. If that's the case, go from there with new cables, figure out a detent system, or whatever. <br /><br /><br />Ed.

 

[JB]

Re: Banging evinrude

Moving to Evinrude Troubles.