1985, 65hp Johnson Outboard with little power

[aopper24]

I am new as a boat owner and bought a used tri-bow runabout boat with a 65hp Johnson motor (seller said it was a 1985 motor that was rebuilt). I'm writing in this forum, because I don't know where to start, and I don't want to walk into a repair place and tell them that I know absolutely nothing.<br /><br />The problem is that the motor rarely gets up to full speed. It usually runs at half speed, and occasionally kicks into the high speed whenever it wants to. There is no apparant reason why this happens. At first, we thought it was old gas in the line, but after being out all day (on several days) with new gas, it still happens. On the rare occasion that it does get going fast, without warning, it will cut back to half speed. <br /><br />Someone recommended getting a new prop, so $200 bucks later, we have a new prop, but it didn't solve the problem. Before I spend any more money I'm hoping someone can give me some advice. And if you can't give advice on what needs to be fixed, can anyone give me advice on how to find someone who can repair the problem?<br /><br />Thanks!!

 

[angus63]

Re: 1985, 65hp Johnson Outboard with little power

Welcome<br />First, whoever recommended the prop change should no longer be consulted.<br />Next, are you planning to troubleshoot yourself? If so, first thing is to verify the model # and get yourself a OMC manual (try theoutboardwizard.com or kencook.com).<br />Next, verify the 3 biggies: compression check, spark check, and fuel supply.<br />If you need help, post back and we'll talk you thru it step by step.<br />If you plan to have someone else do it, I suggest an OMC certified mechanic who comes recommended from local boaters near you.<br />From your symptoms, sounds to me you are dropping a cylinder sporadically, probably the source is thermal or electrical, and I'd look at the coil grounds for starters. If your able, stop the motor when you are down on power, look at the spark plugs, and the wet one will narrow it down for ya.<br />Good luck

 

[djzyla1980]

Re: 1985, 65hp Johnson Outboard with little power

Either spark.... or fuel. If the spark checks out good, My guess is a clogged high speed jet in the carbs. Next time your out take a spray bottle filled with premix and spray it into the carb throats... if it picks up then you gottsa fuel delivery issue. Start with the basics: fuel lines... check for cracks or bad clamps that could allow air into the lines. or even a clogged pick-up in the tank. From there move towards the carbs... inspect gas pump... and the least look at carbs...<br />If your gunna pull them might as well soak, clean and rebuild...don't waste the time just cleaning.... <br /><br />Find this and much more useful information in the handy dandy manual designed specifically for your motor!!! This is a must as it will save you time, money, and you will better understand any information given on here =o)

 

[blackwaterstout]

Re: 1985, 65hp Johnson Outboard with little power

These guys are right. It's either spark or fuel. I had a similar problem with my '79 johnny and it turned out to be a faulty power pack. Just make sure you do a good spark test. If a cylinder ends up not firing try swapping the coils around to see if the misfire moves with the coils. If so you could have a burned out coil. If the misfire does not move around (like mine) then it might be a power pack. Also you should make sure you buy a service manual because they often have troubleshooting tips and a section on testing electrical components with an ohm meter.

 

[aopper24]

Re: 1985, 65hp Johnson Outboard with little power

Geez, you guys are great! I really appreciate all of the advice. I think we're going to try to take it out this weekend, and hopefully now we can narrow the problem down.<br /><br />Although I'd like to be able to do it all myself, everything sounds quite complicated. We will most likely narrow down the problem, then consult someone who is certified to repair.<br /><br />Thanks for all of your help...and if anyone knows/trusts any repair people in the Phoenix area, I'd appreciate a recommendation!