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Engine sitting for many years. What to check?

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Bman396xfd

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Just picked up a 87 Evinrude 150hp extremely cheap. Guy has had it off the boat on a stand for quite a few years. Said he fogged it down good before hand. I got it home. Pulled the plugs and shot some oil into all the cylinders and rotated it over by hand a few revolutions. Then more oil. Then more spinning it over. Hooked up the controls and a battery and it spun it over with the starter. All 6 holes felt like pretty good compression (my tester is bad and new one isn't in yet).

I figured it needs the carbs gone through. Impeller replaced. Gear oil. Looks to need a fuel pump ( it leaks when primer is squeezed). New plugs because it has a set of electrodeless plugs like what you'd get in a mercury?

anything else I need to go over on an engine that's sat for awhile?

curiosity got me and I did hook up a small tank and it to my surprise started right up with little fuss. But I shut it right back off.
 
I've been going through the same thing this past winter ticking over everything on our 2004 Johnson 150 that sat for a few years. Looks like you know what you're doing for the most part. I went ahead and got rid of the OMS/VRO pump and swapped for a normal two stage pump from Offshore Marine. I'm sure you've heard the stories, not sure what an '87 would have from factory.

If you've got the patience I'd check over the rubber hoses on the fuel side for leaks. Also maybe look into replacing the fuel rail o-rings at the throttle body. There's a technique you can use by splicing in clear tubing at different sections of the system and watch for air bubbles to track down a leak. Problem is the system not getting primed enough could have a lot of sources. Carb floats being one of them. I'd go ahead and order full carb rebuild kits or at least the bowl gaskets and manifold gasket once you take them off and break them open for inspection.

Our Vapor Separator was leaking, also had a couple deformed fuel rail o-rings. And a couple of the carb floats were not "in spec" and likely were causing a seal problem. Our engine did start up pretty easily mind you and ran before any real work was done. I'd replace the thermostats if it has them. At the very least remove the carb drain bolts and siphon some fresh gas through the entire system and out the drains. I'd recommend removing the carbs and giving the tiny idle circuit emulsion tube and jets a cleaning while also removing the hoses going to the throttle bodies and inspecting them. You don't want to give the carbs a nice clean and put it back together only to send whatever was sitting in the fuel hoses back into the freshly clean carbs first time you run the system.

Lync and sync is something that is really up to you. All of the butterflies on ours open at the same exact time and open at the same rate so it seems like its okay to just run at factory mixture settings and leave it. Still might take to a professional. Usually the factory idle mixture settings are a little lean as well so maybe an extra turn out would do well (I believe on most of these Johnson 150s its a fuel metering needle valve not air). I'd get an FSM, PDFs can be had online for much cheaper than a physcial copy.
 
Id for sure check compression, do away with the VRO and use gas/oil mix. Since you just have the motor you shouldnt have to deal with the alarm when you put it on a boat. Since yours might need a new fuel pump anyways you can use a non/VRO pump and save yourself several bucks. My 88 E-rude 150 pump went out and the original was a VRO pump which I disconnected the VRO and used gas/oil mix. The OEM VRO pump was like $595 and the non/VRO pump was $430. Now these are OEM price`s which I like to use OEM parts when I can.
 
Cham.. the original posters motor is totally different from yours as his a 90°. Bman dont do anything till compression is tested as these motors are known for ring failures.
 
You save even more $ if you install 2 pumps like these used in 1983 and earlier.----Likely find a pair ( used ) for $100 with careful shopping.
 
I'll have to grab a local tester then. Just mose of these store brands are junk nowadays. Like I say. Even just spinning the engine over without the starter it had enough compression to blow my finger off of each hole. And the cranking sounded nice and even. How common is this ring issue? I was looking into these and never saw the rings mentioned as a "known" failure point.
 
Every Johnrude V4-6 crossflow made from1973 to date is subject to ring failure due to design of the piston and pressure backed rings. Cheap fuel/oil and cooling problems made coke behind rings and forced ring out which catches in port edge and breaks.
 
Solution to keeping it happy would be run a higher octane in the engine? I only run the Evinrude oil. Should I do a decarb on this motor from the get go? This engine really is just a temporary swap until my intruder gets it's water intrusion issues repaired. Then it's going back on. But I do wanna get it straightened out as I have a large lowe deck boat that this engine will then end up on.
 
Agreed----Took a bushel basket full of pistons with broken rings to the recycler.-----Have bunch of these motors in the shed for parts.----A very common issue and every crossflow motor will suffer from it at some point !
 
Compression tester from parts store was junk. I Tested it against my 70hp which I know all the cylinders are 110-120 as I checked them last fall with a borrowed tester. and the new one wouldn't read over 60psi . Replacement also junk did the same thing. Ive had this happen before and I'm pretty sure Its the hoses on these cheapo parts store brands. So I'm getting with my Buddy to let me use his when he gets a chance.

But I pushed ahead with the engine. Not spending any more money on it haha. Blew the carbs out good. Lubed the sticky throttle arm and got it moving freely. The plugs are those surface gap plugs. I didn't think those belong in a omc but I guess from reading they actually are spec for the engine. They plug end (not the engine side) was rusty on all of them. But I Got it running on some muffs and at first I didn't think it was pumping as I had no peeing. Well dirt wasps plugged the pee hole and the hose. Got all that cleaned and It is pumping water good. Still planning on a new impeller before it sees a lake. And probably thermostats. Ran mixed gas mixed pretty heavy for the initial run. it would run great then it would cut out a cylinder. Then it would lope kinda funny? Then it would run good again just like a switch flipped.

So I figured it was those plugs and I figured the plug wire ends were also likey rusted. And bingo. They were. Cleaned all that up best I can. (Definitely needs new wires) And I had good spark on all but one. It would come and go. So that was my first sure missing cylinder.

Did some digging and turns out the last person installed the coil packs managed to pinch the wire going to that coil under the coil above it and the block. Shorting it to ground intermittently. So I spliced a new wire on it from a parts motor and ta da. Perfect spark on that plug. I bet the last guy was chasing his tail bad trying to figure that miss out haha. And after all that it did do away with the cylinders cutting out.

It's Running great actually. Very well for an engine that's sat so long. It fires right up just bump the starter. Revs clean. Very happy with it. I did hear a beeping coming from the controls. Shut it off as I thought it was the over heat alarm. Block felt fine temp wise. But it turns out the over heat is a constant tone. This was the beeping back to back. So the VRO? It's not hooked to the tank. And it's plugged off on the oil inlet. But it did take a good while of me running and playing with it before it bothered to set that alarm haha. So yeah maybe not the most reliable warning system. Tested the overheat by grounding the sensor and I got the constant beep tone. So that's working.

So I'm pretty happy with it at this point.
 
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