64' Evinrude 40hp starts but no power

[Dennisred01]

I've got a 64' evinrude 40 horse. It starts and sounds fine but will not push the boat faster than a few miles an hour. The boat did sit for about ten years and ran fine for around a week before this started. I did a compression test on the cylinders and the top one clocked at about 100 and the bottom at about 120. Also the top plug is clean like it is brand new and the bottom is all fouled up with oil. I did a spark test to see if both cylinders were firing with no results. I am not real sure the guy who was helping me knew what he was doing. Does anyone have any suggestions on where to go with this next. Thanks.

 

[Droll]

Re: 64' Evinrude 40hp starts but no power

Check plugtype ,plug gap :<br />Use champion J4C gap 30<br /><br />Check the points , clean/adjust , points set at .020 .<br /><br />If you those covered .<br /><br />

Also the top plug is clean like it is brand new

Blown headgaske ? > water in the cylinder ?<br /><br />If you remove the plug , can you see the top of the piston , does this look clean too ??, if so you might want to remove the cylinder head and replace the gasket .<br /><br />Things to do :<br />-Get a good spark of bouth cylinders.<br />-Find out why the top plug are soo clean.<br />-Rebuild/clean the carburator.<br />-Replace the impaller , you are 8+ yeare overdue

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Thanks for the quick reply. I just went and checked the spark again, and I definitely have spark on the bottom but nothing on the top. I kind of suspected that with the plug being so clean. Although I still havn't ruled out a blown headgasket. What can be the cause of a plug not firing? My guess would be the coil. Also I should have added that when the boat is running there seems to be alot of oil coming out of the exhaust, certainly too much to be normal. Thanks.

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Droll, I forgot to ask you, what is the impaller. I know a little about engines but not a whole lot. Thanks.

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

Dennisred - if you're misfiring on one cylinder, you'll get lots of unburnt oil out the exhaust.<br /><br />The coil would be the number-one suspect, but first try disconnecting and isolating the two low voltage wires that come down from underneath the flywheel. Then check for spark again. If you still have no spark on the top, it's time to pull the flywheel and check the ignition components. Iboats carries just about anything you need for parts pretty cheap.<br />Other possibilities are points, condensors, and last wires, which are all up underneath the flywheel. Do not attempt to pull the flywheel with any other tool than one which acts on the three bolt-holes in the centre of the flywheel, or you will damage it. A beefy harmonic balancer puller with three grade 8 1/4"x20tpi bolts about 3" long works to pull the flywheel, in addition to the proper flywheel puller tool.<br />When you have it off, if a coil is bad it will be obvious. They normally fail from having their insulation crack. Points will work so long as they're clean, and you can test your condensors by swapping them and seeing if the problem follows a condensor.<br /><br />When all is well, the sparks should be able to jump a 7/16" gap.<br /><br />Good luck!

 

[Droll]

Re: 64' Evinrude 40hp starts but no power

Your waterpump does contain a impeller , should be replaced every second year .<br />

<br />These are replaced , should look like the one on the right .<br />The left one was .... might win the lottery this time

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Thanks alot guys for your help. I pulled the flywheel today and the one coil is definitely fried. I am going to change both coils, points, and condensers this week. I am also going to take your advise and rebuild the carb and change the impeller. My question now is when I change the impeller do I need to get a seal kit with that. I bought a manual but it does not seem to get to specific. I will let you know how it turns out when I am done. Thanks again.

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

There are no seals you will need to change the impeller. If you can though, try to disassemble the water pump before you order an impeller. If you end up destroying the housing, then you'll have to order a new water pump, and it comes with an impeller.<br />But I suppose having a spare wouldn't be much of a problem.<br /><br />Droll - that one on the left deserves to be hung on The Wall of Shame! Next to the brake 'pad' from my brother's car that has no lining or even rivets left.

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Guys, when I took the lower unit off to change the impeller I did not find any gaskets. Is this normal? I kind of figured there would be at least one gasket down there. When I drain the oil out there was quite a bit of water that came out with it. Let me know what you think. Thanks.

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

No gaskets is normal for these water pumps. I put sealer between the wear plate and the gearcase as the OEM manual calls for. Others here don't, and it works fine for them too. To be honest, it doesn't look like anyone ever put sealant on any of my gearcases before I got them. I doubt OMC did!<br /><br />First, replace the two fill/vent screw gaskets with new ones and test it out. Most often, leaks are through those.<br />If it's still getting water into it, you're going to have to reseal the gearcase. Before tearing into it, rig up some way to blow air into the gearcase through the fill screw. A modified tire valve stem and a bicycle pump works. Then submerge the lower unit in a kiddie pool or something and blow air into it. Then you know where your leak is before you take it apart.<br />Never apply more than about 5psi to one of these gearcases. Manual spec calls for 3psi for a pressure test. So be gentle with the bicycle pump if you use one.<br />If that's a manual gearcase on your 40hp (as opposed to an electromatic), it's pretty easy to work on with basic tools. The only real tricky part is getting the shift rod bushing out to replace the shift rod seal.<br />Let us know what you find.

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Paul, the fill/drain screws did not even have gaskets on them. That probably is the problem(I hope). I assume putting o-rings on the the screws would do the trick?

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

Pick up the correct gaskets from your local Johnny/Rude dealer. They're really cheap and should be used only once. <br /><br />They're a sort of nylon washer. O-rings might get you by, but I would worry about the screws working loose. You won't be able to get the screws very tight with the o-rings without tearing them up.<br /><br />If there were no gaskets at all, I think that would account for your leak. The gearcase heats up and cools off after use, so it tends to suck water in.

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Alright, I got my engine put back together and started up. Now, my question is this, how do I know if I put the impeller in right. When I put it back I wasn't 100% sure it was going the right way. I do not think the temperature light works, so if it overheats I am not going to know it. <br /><br /><br />Also there is alot of oil in the water and it is smoking like hell. I did not adjust the carb yet cause I am having wire problems. I got to go get new ones. So I am thinking that the oil is from the adjustment. Not sure about the smoke. Any tips?

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

Smoking always appears much worse in the barrel then on the water, as does the oil slick. But if you've got excessive smoke, that usually indicates you are running rich. Check your plugs to be sure. <br />With those long-vaned OMC impellers, it really doesn't matter if you got it in backwards. They'll flip over when you run them up. <br /><br />Good luck!<br /><br />EDIT: I forgot. Have you got good spark on both cylinders now? How does it seem to run? Better than before?

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

I am still having problem with this thing. I do have spark on both cylinders, but I cannont get it to stay running for more than 20sec. The plugs are getting wet and coated with oil after cranking the engine a couple of times. I do not know how to adjust it so it is not running so rich. It seems almost like it is a choke problem now. <br /><br />Also after cranking it and getting it running for a few seconds here and there, there is no water coming out of the lower unit when picking it up out of the barrell. There is plenty of smoke coming out though. The only thing that I can think of is that I did not get the water tubes lined up right. Let me know what you think? Thanks.

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

Which choke system do you have? Is it the heat choke with the single metal line running from the exhaust manifold out to the carburetor, or the water choke with the flexable lines running to it?<br />I take it it's not the mechanical or electric only choke, since their operation is obvious and there are no adjustments.<br /><br />Make sure you've got the water up over where the waterpump is when you run it. These pumps aren't great at drawing water. Also, you shouldn't see hardly any water come out the big hole in the back until the engine warms up a bit and the thermostat opens, and it starts dumping hot water. Keep you eye on the engine and make sure it doesn't overheat until it does though.<br /><br />What exactly have you repaired/rebuilt/replaced on this engine since it started acting up?

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

It is the electric and hot air choke system. So far I have rebuilt the carb(rebuild kit w/float), replaced both coils, points, condensers, and I replaced the impeller. I also had to wire a new ignition switch and hook up the choke switch and temp light. <br /><br />I did tear the choke system apart when I tore down the carb. It has the lean w/arrow on the side of the plate. This is adjustable by loosening 3 screws holding it in place and turning it one way or the other. This is the only thing I can think of that would be adjustable. I marked it and put it back the same way it came apart. Somthing obviously went wrong somewhere.<br /><br />The clymer manual that I bought seems to be pretty much worthless to me. If I do not end up taking the boat to the shop would it be worth my while to buy a different brand manual? Thanks.

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

I should add that there is gas dripping out of the front of the carb. This is the reason I decided to rebuild in the first place.

 

[Paul Moir]

Re: 64' Evinrude 40hp starts but no power

Ok, I wasn't sure how far you had gone with the ignition system. Clearly, there's little left to go wrong there!<br />On the right hand side of the heat choke carburetor is a lever so you can override the choke plate. Try manipulating it so you can rule out the engine is being overchoked. You did good marking the heat choke calibration before you disassembled it.<br /><br />There's only a few other reasons you could be running rich. One is that the float needle and seat are leeking, but you would notice that because when you pump the primer bulb, it'll never get hard. And you'll be pumping gas out of the front of the carb with it.<br />Second, is that the float level wasn't set (correctly). When you turned the carb upside down, the float should have appeared even with the rim of the carb body casting.<br />Third, your lean mixture is set very rich. This would only be a problem at idle speeds though.<br />Fourth, I belive your carburetor has a little round gasket between the bottom of the main nozzle and the pit in the bowl it fits into. Was this innocuous gasket replaced? Was it in good condition?<br /><br />I've got to agree about the manual. The Clymers for this age and type of outboard is less than stellar, if it's the same Clymers as the one I've seen. I personally like the aftermarket Seloc one better, but you won't find it's much different from your Clymers. Keep an eye on ebay for the superior OEM manual (search 'Johnson Manual' or 'Evinrude Manual') since they go for a song there compared with reprints elsewere. Currently I only see a '68 40hp though. Marine Engine has a per page copy service that might be useful too.<br />Iboats is your best resource though. You'll find more here than all three manuals put together.<br /><br />Good luck!

 

[Dennisred01]

Re: 64' Evinrude 40hp starts but no power

Ok, this thing is starting to drive me nuts. I have an appointment next tuesday to have it looked at, so I have till' then to try and figure this out.<br /><br />I jammed the choke lever so that it would stay off. When I turned the ignition it started right up and the idle went through the roof and than stalled. I am stumped, is this a choke, timing, or an idle problem. I did mess with the choke calibration to no avail. When I do get it started without manipulating the choke, I have to jam on the throttle and it sounds really bad and eventually stalls anyhow. Let me know what you think. Thanks.