'76 Evinrude 85 HP No Top End

[texxpaisley]

Hi Everyone - I just bought a 76 glastron 16 with an 85 hp Evinrude. It has been running great until last week. I forgot to run it dry, but the next time I started it up it idled fine and ran at low rmp fine. When I pushed it to full throttle, it would only go about 1/3 as fast as before, and could not even get the boat planing. If idles fine and cruises fine, but no top end. Just after that, the throttle cable went, which I have replaced, but the top end has not come back. Any ideas? Thanks!

 

[rickdb1boat]

Re: '76 Evinrude 85 HP No Top End

Push the throttle lever all the way forward and Look in the carb. throats and make sure all the throttle plates are fully open(Horizontal). You may need to adjust the linkage. Also, make sure the timing plate is fully advanced. This is a start. Post back what you find. You may also want to check the spark on each cylinder to make sure they are all firing. If you drop one cylinder, it will act the same way.

 

[Solittle]

Re: '76 Evinrude 85 HP No Top End

Tex - Take it out again and bring a spray bottle of pre mix with you. Take the cover off and try to run it. When it boggs down spray some of the pre mix into the carbs. If it picks up you have a fuel problem. I suspect that you will need to rebuild the carbs due to crud somewhere.<br /><br />Oh and a big welcome!!!

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Thanks for the quick replies, and the welcome. I'll try your suggestions and post back what happens.<br /><br />Texx

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

I haven't had a chance to try out your suggestions yet, but plan to this weekend. I did pull the spark plugs and they were seriously fouled with black carbon and black oil so I'm gussing I am running it a bit rich or too much oil to gas. As I began working on it I ran into another problem - oil was leaking out of the lower unit through two small holes just below to the center of the mounting bolts and through where the propeller meets the lower unit. I took some pictures of the holes. Is this a serious problem or just excess oil running out of weep holes? Thanks!!!<br /><br /><br />Pictuers of the lower unit are here:<br /><br /> http://www.angelfire.com/falcon/aguas/boat/

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

BTW, there is one hole on the left side and two on the right. The oil was dripping out of the two on the right side of the LU.<br /><br />Texx

 

[phatmanmike]

Re: '76 Evinrude 85 HP No Top End

that is unburnet exhasut mor than likely, as to why the holes are there, thats anybodys guess...

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

I opend up the carbs and checked the linkage and throttle plates - all seemed ok. The throttle plates were open all the way at WOT. I did not check the timing plate - not sure how to do that. Any advice would be great. I do have a manual but it is not very clear.<br /><br />I don't think it is a lack of fuel, since all 4 plugs were pretty heavily wet fouled and there was a lot of blow-by oil in the exhaust. I'm taling the boat out this weekend to test it and will post back.<br /><br />Tex

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

I took the boat out this morning and here's what happened: The boat ran well at idle and low rpm, started easily. It still did not have any top end, but a new problem came out of the deal - after a minute or two of WOT trying to get on a plane it ran out of gas. If I squeezed the primer bulb it ran ok, still no top end but would run as long as I kept squeezing the primer bulb ever 30 seconds or so. Feels like I'm chasing a phantom!

 

[nedct]

Re: '76 Evinrude 85 HP No Top End

Well Bro', the the pro sound's familar,,,, all too !!! replace your fuel pump...<br />also try the water pump assembly(imp).. i had the same prob... water pump : helped the power loss.. and the Bogging is the fuel pump...60 for the waterpump and 40 for the fuel pump.. about..

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Thanks, I'll check that out. I really appreciate everyone's help!

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Just a quick update: I disconnected the fuel line from the engine and tryied pumping it and it still was "soggy" and I could hear gas sloshing in and out of the tank. Tried this with my other tank as well and got the same result. Disconnected from the tank(s) and the bulb got hard like it is supposed to. Are the withdrawal assemblies on my tanks broken?

 

[bubbakat]

Re: '76 Evinrude 85 HP No Top End

Sounds like you have the primmer bulb hooked up backwards.

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

The arrow is pointing the right way and when I switch it around it does not pump at all. BTW, this was a premade bulb/fuel line kit from OMC. My old one still works, but it has some cracks in the outer skin so I wanted to replace it. I'm going to switch the bulb with a new one tomorrow. Thx.<br /><br />Tex

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Got the new fuel pump today, but haven't had a chance to fire it up. Do y'all think that this could be my loss of power problem at WOT too? Thanks.<br /><br />Tex

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Hi all - the new fuel pump is working great. I still have a loss of high end power. I did notice today that the warmup lever gets the rpms much higher than the throttle. Don't know if that bit of insight will help or not. I'm going to rebuild the carbs this week and we'll see how that goes.

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Pulled the plugs again after today's run and the cylynders on the right look like normal wear, both of the ones on the left the plugs are clean - looks like no wear at all, no oil, no nothin. The engine is peeing good, even at idle. Did I do something hidiously wrong?

 

[texxpaisley]

Re: '76 Evinrude 85 HP No Top End

Found the problem; it was the power pack. For details see the topic: Evinrude v4 Plugs on one side clean<br /><br />Thanks everyone for your help!<br /><br />Tex