58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hello. I restored a 1958 Evinrude 5.5 hp outboard (Fisherman model, #5516) over the winter. Completely rebuilt the powerhead, replaced all seals, etc. It ran wonderfully for the first three runs (about 20 min., 35 min., and 1 hour respectively). On the third run, it began to sputter just as we returned to the dock.<br /><br />Now I think I'm facing a combination of two difficulties here... a combination of cooling and fuel problems. Here's why:<br /><br />Next time I took the motor to the water, it took dozens and dozens of pulls to get the motor started. When it did start, I noticed some fuel leaking at the quick disconnect, but only a few drops. The pressure tank is definitely getting pressure (hisses if you open the cap) and the motor is apparently getting enough fuel to finally start. After it started, it smoked more than usual. Ran for 30 seconds, but I shut it down because of the smoke and because the lower unit already felt warm to the touch.<br /><br />Thinking it might be a cooling problem, I pulled the lower unit off and replaced the impeller and impeller plate (for the waterpump), though the old ones looked to be in reasonably good condition.<br /><br />Next time I started the motor, it still smoked down near the water and out the exhaust hole, so I shut it off again within about 30 seconds. I can't remember, but isn't water supposed to pump steadily out the exhaust hole? All I'm getting is a misty air, with very little mist (99% hot air exhaust). But I replaced the water pump already, so could it still be a water pump problem, or am I wrong to expect water out the exhaust hole? (When I say "exhaust hole," I'm talking about the hole located about 8 inches above the cavitation plate, not the hole down under the cavitation plate near the prop, which I assume to be the water intake, right?) I'm afraid to run the motor for long because I don't want to burn it up.<br /><br />Meanwhile, because of the fuel leakage, I'm guessing the starting troubles might be due to some bad O-rings in the quick disconnect, so I've ordered some to replace. But the leakage is pretty small, and the symptom is this: Difficult to start, and once it does start, an increasing amount of throttle must be applied to keep the motor running, until it finally sputters and dies when the throttle maxes out (engine doesn't rev with the throttle increase... just barely stays running). Any ideas?<br /><br />Lastly, I ran the motor on a 40:1 mix, but I just read on the iBoats forum that 24:1 is the proper mix for an older Evinrude like my '58. Is that correct? Could that be related to my problems?<br /><br />By the way, the prop definitely turns, and the water churns even when the motor runs at idle in neutral, so some kind of "exhausting" is going on under the water, but I thought water was supposed to pump out the exhaust above the water also (about 8 inches above the cavitation plate).<br /><br />Thanks!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hey Wesley....we'll see if we can help.<br /><br />First...fuel mix is 24:1. I would'nt run anything less.<br /><br />With that much oil you can expect it to "smoke" a little. If the connector is leaking, definetly replace the orings. You might also check the connector and make sure there is no burrs on it that might be tearing up the orings.<br /><br />Check your point settings. One point setting that has gone awry will mess up the whole engine operation.<br /><br />I can't remember right off the top of my head if the 58's have a t-stat. But you can check engine temp with your fingers.....after it has idled for a while, touch the flat place on top of the engine just forward of the head. You should be able to lay your fingers there for several seconds. If you can't, the engine may have an over heat problem.<br /><br />What are your carb low and high speed needle settings? Make sure the packing follower nut is snug so air won't leak in around the needles.<br /><br />All you should get is a misty spray out of the exhaust relief ports.<br /><br />You might also check the carb bowl for junk. Next time you try to start her, shoot some premix into the carb throat. If she fires right away, you may have a fuel flow problem.<br /><br />Don't hesitate to post if you have any questions.....thanks!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Thanks OBJ... no T-stat, but I'll try the overheat check you mention. It'll be a couple of days before I post the results, as I also want to switch out the O-rings in the fuel disconnect before I take her to the water again to try starting.<br /><br />I could've sworn that the three times I had her running, there was a steady stream of water shooting out the upper exhaust port, but maybe what I was seeing was just the ripples/splashes on the surface of the water caused by the hot air exhaust blowing out strongly. Hearing you say that just a mist is normal makes me feel a lot better... I was really worried I might be burning up the gearcase with a faulty waterpump or something like that.<br /><br />Thanks again!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi Wesley,<br /> Yes, there should be a steady spray out the hole you noticed. If it's anything less, you've got a blockage or bad pump. Those 5.5s didn't have a t-stat, but they did find that they were running too cool and carboning up moreso than they should have. With that in mind, it may have a restrictor in the water tube between the pump and powerhead. I'm not sure when they added it, but it was mid-late 1950s. The restrictor is basically a piece of rubber hose crimped into place in the tube to restrict the amount of water entering the powerhead and allow it to run cooler. The downside of this is the restrictor is a good place to pick up bits of seaweed, grit, flotsam, etc. I'd check to make sure it's not plugged up...<br /><br />- Scott

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Thanks Scott... I'll check the water tube. Is there anything to the "waterpump" besides the impeller and impeller plate? I replaced those before the last test run, but was still only getting a hot air exhaust (no water, maybe 1% mist) out the hole I mentioned. So maybe it is a blockage in the tube... or is there any critical part to the waterpump down inside the gearcase? I hate to tear that open, but I guess I could if you think the problem might lie down there somewhere (near the prop).<br /><br />Thanks!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi Wesley,<br /> As long as the pathway from the water intake to the pump plate is clear, you should be alright. Nothing else to the pump system other than the drive pin - in place? Also, make sure the unit is submerged up to and including the pump area..<br /> You can "bench test" the pump by submerging the unit in a bucket and spinning the driveshaft with a drill. Cordless drill is preferred...<br />- Scott

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Wesley,<br /><br />If your motor is overheating, you may want to pull the cylinder head and make sure you have evidence of water in the passages around your cylinders. These passages are quite small and easily plugged up. You may want to take an air hose and small wires and trace the entire route of water as it is pumped up and through the powerhead and then back out into the exhaust. You can see where I did this on a 3 HP Lightwin at http://www.outboard-boat-motor-repa... Johnson 3 HP 1952-1967 Water Circulation.htm <br />As you can see, I had to clean out a lot of crud but it was well worth it as the motor is running nice and cool now.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Thanks Scott for the suggestion about "bench testing" the waterpump. I never thought of using a cordless drill to spin the shaft, but it makes sense... a great idea for checking if the pump is functioning properly. What do you use to attach the cordless drill to the shaft? I'd be concerned about harming the splines on the top of the shaft (the splines that index into the bottom of the powerhead, I mean). Or did you mean that I should spin the whole shaft (with powerhead still attached) by putting the drill on the flywheel nut?<br /><br />Tom, I think the passages around the head should be clear, as I did a complete rebuild of the powerhead over the winter and the motor has only been run three times since then. I cleaned out the crud from the channel with a pick and a Dremel rotary tool with a small wire brush attached. Then I used an air compressor to blow the channel free of debris. If the other suggestions don't fix the problem, I'll pull the head as you recommend.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

By the way... I figured out what wrecked the O-rings in my fuel disconnect. I restored the motor to use on a small sailboat I'm building with my fiancee to sail on our honeymoon. Yesterday, while in the garage, I realized that I had cut the motor well just a hair too small, so that when the starter pawl is yanked, the motor pivots and bangs the quick disconnect on the side of the transom... I cut it two inches larger so now the motor can be pull-started without the disconnect rubbing or banging against anything. Hopefully, that will resolve my starting troubles when I replace the O-rings today, but I'll update you all on the source of the cooling problem once I get that fixed. And really, thanks for all of your help/suggestions guys!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi Wesley,<br /> The drill chuck shouldn't do anything to the driveshaft splines. Obviously, you'd need something larger than a 3/8" chuck. It doesn't have to be terribly tight on the shaft, as there shouldn't be a whole lot of friction on it, some, but not nearly as much as drilling through a piece of hardwood...<br /> Oh year, do the test with the unit in neutral. You'll have your hands full trying to hold the unit, the drill, etc. without it trying to propel its way through the water as you're doing it. <br /><br />- Scott

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi guys,<br /><br />Well I installed new O-rings. I also opened the lower unit again and re-checked the waterpump. I tried Scott's suggestion of spinning the driveshaft with my drill, and the pump is definitely pumping. It wasn't an incredibly strong flow of water, but it bubbled out healthily from the top of the pump housing. I assume if it were connected to the water uptake tube, it could create a healthy vaccuum and pull water through nicely.<br /><br />I cleaned the water uptake tube with an aquarium brush and found no blockages. I can't see any blockages under the motor anywhere either, so I think the water channel must be clear.<br /><br />The O-rings definitely stopped any fuel leakage at the quick disconnect. They also seem to have helped some of the starting troubles significantly... The motor definitely wants to start on the first few pulls, but it still seems to have trouble staying running after it has begun to start up. I was doing a bucket test, so I didn't want to crank the throttle too much, but I'm worried when I get it to the water in the next day or so (it's raining now), it's going to suffer the same symptoms as before: namely, to require an increasing amount of throttle to stay running, until the throttle maxes out and the engine dies. But we'll see.<br /><br />I also installed a new seal and a fresh gasket under the powerhead, so everything should be sealed up tightly if it was ever disturbed by my previous disassembly.<br /><br />The low-speed needle is adjusted 1/4 to 1/2 turn out from closed, and the high-speed needle valve is adjusted about 3/4 to 1 turn out from closed. I'm not sure if those might be factors. That's where I set them when I originally got the motor running earlier this year (when it ran wonderfully well) and then "tuned" them out on the water, but I have moved them now, so I went back to the SELOC manual's recommendations for initial settings. Any ideas?<br /><br />I'll report back about what happens if I get to try starting her at the lake tomorrow.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

New question: I noticed a small (approx 1/8" dia.) hole in the underside of the cavitation plate, just above the propeller. The hole opens into the same compartment that the submerged exhaust (where the exhaust screen is located) opens into, so it's definitely a compartment that normally fills with water (and which feeds the water pump). When I put my finger to the hole this morning, and pulled it away again, my fingertip was coated with an oil/gas mixture.<br /><br />So I'm wondering: Does this mean that maybe my main seal under the powerhead is bad or not fully sealed? I can't think of any other way that the fuel mixture could get into the cooling water channels, but I think maybe that's what's happening... which might explain why the motor has trouble running AND why the lower unit smokes within just a few seconds (literally within just a second or two) of starting the motor. What do you guys think? I just installed a new powerhead-to-lower-unit gasket. And I think the bolts are tight. So what gives? Is there something I'm not considering here?

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi Wesley,<br /> That's completely normal to find the oil residue. 2-strokes by their very nature are somewhat "dirty" and will leave a small amount of unburned fuel/oil behind. Some will tend to collect in the cavities and recesses of the motor's lower end, which is part of the reason why that hole is there to begin with. All of the exhaust mingles with the cooling water on the way down the leg, so whatever unburned fuel is in the exhaust will show up there. <br /> As for the running issue - low speed should probably start around 1.5 turns from closed and the high speed around 1 full turn. Somewhere on the site Joe Reeves has a great "how to" description on setting the needles.<br />- Scott

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Wesley K.<br />One thing I have found on my 2 old 6hp's (CD22 & 6R77M) is that the cover and seal retainer housing underneath the water pump suffers from corrosion and when bad allows water pressure to escape from the pump housing and down into the exhaust cavity in the lower leg.<br />I replaced the plate with a new one and restored the water flow to max again.<br /><br />Regards<br /><br />Peter

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Thanks Scott.<br /><br />Peter, I replaced the impeller plate and the impeller. The waterpump housing seems to be in good condition, though I replaced the water-tube grommet.<br /><br />The cover and seal retainer housing you refer to are, I assume, the pieces just BELOW the impeller plate. One interesting thing I noticed when I removed the impeller plate the last time... the SELOC manual and original parts manual show a "bearing seal" that sits on TOP of the bearing housing, just BELOW the impeller plate (sandwiched between the two, I guess). Mine does not seem to have this seal... That seems like a problem to me, except that the motor has run fine before with no troubles whatsoever. Is it possible mine isn't supposed to have that seal? I can't figure out what it would do anyway, as it would be positioned between two static (unmoving) parts. If I lift up the bearing housing, there does seem to be a seal or some kind of round, similar-sized object UNDER that... I don't know.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

UPDATE... Well, had a chance to get to the river. No luck.<br /><br />The waterpump is almost certainly working now. Even a few hand-pulls on the starter will get a healthy trickle (small stream, actually) of water running out the upper exhaust port. And when the motor starts to grab, it turns into a coughing spray of water that looks very healthy. So the cooling problem is fixed, and the smoke from the lower unit seems to have cleared up, though it might smoke a bit if I ever get the engine to run more than 2 seconds again.<br /><br />Now the problem seems to lie somewhere in the powerhead or ignition system. The quick disconnect is not leaking, and it fits on TIGHTLY, so I think it's either the carburetor or the ignition coils/plugs/wires. I guess I'll go through the ignition system tonight to see if I'm getting spark out of both plugs, and I'll recheck my point settings, etc. I pulled the carburetor off at the river today and there was a lot of fuel inside, but no visible blockages. A bit of crud in the fuel bowl is all, but the rest looked clean.<br /><br />How can I tell if a coil is "bad"? I know a blown coil will actually look broken with its side blown out, but is there any other way a coil can go "bad" that is less visible and less easily detected? If I can get a spark out of both plugs, that means the coils must be good, right?<br /><br />I'm getting desperate now... our honeymoon is only about six weeks away, so I need to get this motor running reliably, or our honeymoon sailing plans will have to be scrapped (unless, of course, we buy a new motor... ugh).<br /><br />Thanks!

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

By the way... forgot to mention that the problem/symptom I'm experiencing now is the one I mentioned before: the throttle has to be cranked to near-maximum in order to get the motor to start at all. It starts very quietly, rises for a moment toward a healthy idle, then gradually winds down again as if it's starved for gas or something... can't keep it running more than about 2-4 seconds because there's no more throttle to give it.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

By far most often a bad coil will have cracks in it's insulation. This causes the engine to miss was teh revs pick up and it's harder to fire off a charge. (breakdown voltage goes way up with compression)<br />A good simple test for the ignition system is to set up a 3/8" gap for it to jump across. You can build a 'tester' by driving a couple nails into a board 3/8" apart, connecting one to the block via a wire, and place the spark plug boot over the other. The ignition system doesn't have to fire 3/8" on every revolution, it should be just capable of it.<br /><br />We'll hang through this with ya! Just bump it up to the top if you don't seem to be getting any replies.<br /><br />EDIT: I've gotten those symptoms with badly cracked coils. Easy enough to check if you've got an inspection plate over the flywheel and a flashlight.

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Hi Wesley,<br /> Did you lightly grease the point cam or add a drop of oil to the cam wick before? It's possible that the points have closed up on you. The fiber rider of the points can wear down fairly quickly if the point cam isn't lubricated.<br /> Also, is the gasket that sits on the main jet standpipe present in the carburetor? It's a thick, round gasket, about the size of a dime with a hole in it. Lacking that gasket could give you the symptoms you've described.<br />- Scott

Re: 58 Evinrude 5.5 hp, model 5516, cooling/fuel?

Wesley,<br />Good news on the pump side. Your coils if they are the OLD type may be faulty.<br />You may need to lift them out and check underneath as I had one that was cracked there and was misfiring. It looked OK from the top.<br />2 new coils after that and I had a 2 cyl engine again. <br /><br />Peter