'83 Evinrude 60HP 2 cylinder decarb

Hey folks,

I am new to boating and outboard mechanics. Last weekend I decarbed my old for the first time. It was running rough late last season and would stall during acceleration unless I jammed the throttle forward and backed off. It started after I began trolling regularly, so it seemed like my issue was carbon build up.

I ended up going with the valvtect spray from west marine. I noticed that when I was spraying into the bottom carb, the motor would cough and start to stall, but when I sprayed into the top carb, the motor had no reaction whatsoever. I looked around and could not find anyone saying this was normal. Basically, I want to know if this is a sign that the carbs need to be rebuilt or maybe I should run seafoam through it instead. The motor smoked like crazy and it idles better now, but I have not had it out in the harbor yet. Any input would be great.

Matt

Re: '83 Evinrude 60HP 2 cylinder decarb

Hey there Matt..I'm not a mechanic but I had issues w my 1984 60hp 2 cylinder Johnson recently. This may help start steering you in the right direction. My mechanic would take me out every time we worked on the motor so that I could decipher issues on my own. Lets say you take the silencer off the carbs: if you completely cover one carb and only allow the other to work your motor should not bog down. If it does then the carb you didn't cover is not getting gas where it needs to be. So rather then spraying into the carbs test rhem that way. Cover your top carb so only the bottom is functioning and if it doesn't start to sputter the bottom is ok. Then repeat for the other, cover the bottom, if it starts to sputter down then you know it's the top carb giving you the problem. It may be as simple as dumping the carb, blowing out the high speed jet, and maybe a thorough cleaning. Which corrected my issue w/o rebuilding. In other words I would start by pulling off your carbs, take out your high speed jets and make sure they're free of debris, and clean the carbs good while you're at it..they may just be gummed up from the ethanol. Hope that helps a little. Phillip.

Re: '83 Evinrude 60HP 2 cylinder decarb

I pulled of the silencer and covered each each carb one at a time and I noticed the same behavior. When the bottom is covered, the motor bogs down. I also noticed that a lot of fuel was coming out of the lower carb. What is the best process for cleaning the carbs without having to take them completely apart? I have a bottle of sea foam on hand, can that be used?

Also, am in any danger of hurting the motor if I take the boat out before resolving this issue?

Re: '83 Evinrude 60HP 2 cylinder decarb

Hi, Matt.

Seems pretty sure that your lower carb is in trouble. Sounds to me like it is running too rich, probably from float or inlet needle troubles. You can drop the float bowl and investigate that possibility without completely dismantling the carb, but even if it worked it would be a half job.

You cannot overhaul a carb without taking it apart and you can't clean it thoroughly without taking it apart. Bite the bullet. Get an OEM Service Manual and a couple carb kits. It would be foolish to go on the water with a sick engine.

Re: '83 Evinrude 60HP 2 cylinder decarb

I picked up a couple carb kits. Judging from the way it looks in the service manual, pulling the carbs and disassembling them looks fairly simple.

There is a ton of information on cleaning carbs. Some say soak, some spray, and some say don't use chemicals. Any input would be greatly appreciated.

Re: '83 Evinrude 60HP 2 cylinder decarb

Matt,

Ok, so from what you explained here's what Seems to be wrong. When you covered your bottom carb that means your motor was running only in the top carb/cylinder. The reason it bogged down is not enough gas flow. Your bottom carb is dumping gas but I'm guessing when you covered your top carb it didn't bog..which would mean this.. It's obviously getting gas to the cylinder, like the last guy posted either you're running too rich due to the needle/float constantly dumping or possibly even leaking from a gasket. You are going to have to pull the carbs completely off the head in order to rebuild or clean them either way. As far as the non replaceable parts you can either use carb cleaner spray or you can soak them in liquid carb cleaner. After you use the kit, anytime you clean your carbs, you're going to want to pull them apart to clean. The carb cleaner can ruin the needle/float. At the same time so will the ethanol gas. I know as many people have told me if you run the gas out you're fine, I take no chances, I only use non-ethanol gas now. Using non-ethanol will save some future headaches! After you get those carbs done do the test over again, cover each one at a time, neither should bog down. Let me know how everything works out for you!

Phillip.

Re: '83 Evinrude 60HP 2 cylinder decarb

Thanks for the info, Philip. I figured that was the case. This evening, I will rebuild the carb, but won't be able to test until tomorrow; out of respect for the neighbors. I'll post my results.

I have been treating my fuel with star tron since non-ethanol fuel doesn't seem to be available in the greater Boston area. Hopefully we will see ethanol replaced with fatty long-chain alcohols sooner than later. There have been tremendous strides in mass producing it and the benefits are incredible. It won't be hygroscopic and will have equal or close to the energy density of gasoline. Also, it is renewable and a much weaker solvent.

Re: '83 Evinrude 60HP 2 cylinder decarb

I just finished rebuilding the carbs and hooked it up to the hose. Now when I cover each carb it bogs down. Did I screw up the float adjustment? I set it exactly where it said it should be. Also, a bit of fuel comes out when I cover a carb and then the motor smokes. Seems like it may still be running a bit rich. I tried adjusting the low speed pin screws, but that didn't do anything. Any suggestions?

Re: '83 Evinrude 60HP 2 cylinder decarb

fender230 said:

I just finished rebuilding the carbs and hooked it up to the hose. Now when I cover each carb it bogs down. Did I screw up the float adjustment? I set it exactly where it said it should be. Also, a bit of fuel comes out when I cover a carb and then the motor smokes. Seems like it may still be running a bit rich. I tried adjusting the low speed pin screws, but that didn't do anything. Any suggestions?

Click to expand...

To clarify. A bit of fuel comes out after I cover each of the carbs, not under normal running conditions.

Re: '83 Evinrude 60HP 2 cylinder decarb

Matt,

I talked to my mechanic this afternoon on my way into work. He said if you put ot together the same way uou pulled it apart chances are you didnt mess up the carb. And he concures that you seem to be running a bit on the rich side. Here's what he told me to have you do. You need to figure out if the root of the problem is fuel based. You may be able to do this idle at home but I've always done it in the boat on the water. Run up speed and hit your choke. If the boat picks up speed due to the engine picking up then your issue is fuel related (may need to go back through the carbs, fuel pump, its not getting the fuel it needs). Now if your engine bogs down as should be normal when u hit the choke then your problem is likely something electrical (could be ignition related, stator, coil pack). But ultimately the 1st thing he said you need to do is rule one out..either electrical or fuel. Let me know what happens when u test it out and if I can't help through my experience I'll call him again and run the scenario by him for an answer.

Re: '83 Evinrude 60HP 2 cylinder decarb

Thanks for the info. I was planning on pulling the carbs again and making sure I didn't screw up the float height. I think that is a likely scenario since it was my first time and human error should always be the first thing investigated. It starts on first crank, so that is cool, but that may be due to it running rich.

I'll let you know what i find.