Evinrude hp diagnosis

[mikesat]

Help! I don't know what happened. I have an 8hp, 1986 long shaft that starts, first pull, everytime and runs my sailboat great. The other day, it died everytime I put it in forward. Neutral:Great, Reverse:great, forward:dies. I can go full speed Backwards, but not a bit forwards. Changed plugs, no difference, changed fuel, no difference. Still starts first pull. Guy told me the cylinder's probably scored. Is this the likliest thing? If so, where do I get one? Help!

 

[12Footer]

Re: Evinrude hp diagnosis

A compression test couldn't hurt. But the fact that it runs fine in reverse,and starts first pull, tells me you may have lower unit issues. Drain the lower unit,and inspect the old lube for signs of water and possably chunks of metal that you can feel with your finger.<br />If you have water contamination,it is probably due to bad driveshaft,shift shaft or prop seal(s).<br />Also, remove the prop and inspect the shaft for monofilament line. It will look like a hairy neoprene washer sometimes. Trash wrapping-up on the prop shaft will ruin a prop shaft seal quickly.

 

[mikesat]

Re: Evinrude hp diagnosis

Wow, you answer fast! Ok, here's what happened. I had already changed the oil in the lower end with no change. Just now, I pulled the prop nut and saw a chewed up pin underneath. The place it went through was pretty chewed up. I pulled the prop and another pin popped out of Who-Knows-Where! It's clean and straight and has a rounded end. What's that? How bad did I mess this up?

 

[JB]

Re: Evinrude hp diagnosis

You may have found two parts of the same pin, Mike. Or, there may have been a spare stored somewhere in the hub. Sounds like you had a sheared pin, but I don't think that was your problem. I think you have one cylinder not making enough (maybe any) power. <br /><br />For starters, crank her up. At idle, pull one plug wire, then the other. If the engine dies or drops rpm that cylinder is making power. If there is little or no change you have a weak or dead cylinder.<br /><br />Let us know what you find and we will take it from there.<br /><br />Red sky at night. . .<br />JB

 

[petryshyn]

Re: Evinrude hp diagnosis

I found one of those clean rounded end pins in the exhaust of an ice-auger ("ice-auger" a small 2-stroke engine mounted on a large drill bit used to make holes in the stiff water we get up here in Canada) The pin turned out to be a main bearing roller

 

[mikesat]

Re: Evinrude hp diagnosis

I'll give the "pull one plug at a time" thing a try, but first, I now have to get my prop back on and figure out where that pin came from. There are definitely two holes in the shaft that holds the prop; one is for the cotter pin that holds on the prop nut, and the one that is broken looks like a shear pin. When I pulled the shaft free, a third pin popped out. The prop's shaft goes into a hole in the bottom end of my outboard. This pin fits within the two mating parts when the prop shaft is installed. I just don't know what it does or which end goes in first, the flat or the rounded end. The broken shear pin I'll have to approximate just to try this out. This brings me to one of my main questions: where do you get parts for this thing? I find suppliers for motors of 25 hp and up, but not for the little guys.

 

[mikesat]

Re: Evinrude hp diagnosis

Ok, just a follow up, problem solved:<br />I found a local Evinrude dealer who had the shear pins. I spent $1.00 and got 2 of them just in case. The stainless pin, rounded on one end goes in rounded end first and the prop shaft goes in on top of it. Once I got the broken-up, old shear pin cleaned out of there, and a new one installed and the whole works re-assembled, it fired right up! I think the shear pin broke in such a way as to let the prop turn in one direction only. I'll need a new prop, because the brass fitting that the shear pin goes through was chewed up, but now I know what caused it all.<br />Thanks for all your help, guys!

 

[12Footer]

Re: Evinrude hp diagnosis

You can take your old prop to a prop shop,and have it rebuilt. It will be cheaper than a new one, and in some cases,cheaper than a used one. (about 40 bukz).

 

[mikesat]

Re: Evinrude hp diagnosis

Thanks, but I found a place, online, that has my prop, new, for $48.00

 

[pegasus1108]

Re: Evinrude hp diagnosis

Hi! I am new in this board. I am glad to find out that you have an 8.0 HP Johnson. I just got one given to me by an old friend. The problem that I am having is that there seem to be no fuel going to the combustion chambers to start the motor initially, the only way I can start it is if I pull the plugs and inject a little fuel. I have cleaned de carburator, replaced the fuel pump, and changed spark plugs. I don't know anything about the setting specification to start resetting the engine to specs. Do you have a operation manual, or a repair manual that you could share for couple of dollars. I priced the repair manual and it is mighty expensive, $34.00 plus tax and covers a variety of engines. I appreciate your help! Thanksnull

 

[Dunk]

Re: Evinrude hp diagnosis

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=1019365829 <br /><br /> Victor, funny you should mention a service manual. If you buy off ebay here's 1990. I doubt there's much difference in any of the 8hp's over the years.