2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

[Boatandfish]

I have 2000 Johnson Ocean Pro (90 hp) Model #J90VLSIF and will attempt to describe my problem... I have searched through lot's of posts in the wealth of knowledge here on iboats and haven't been able to solve the problem. Visually, it does not appear that this engine has had alot of use.

The engine ran great earlier this summer at idle, low speed and WOT(5300 rpm). After using the boat around 3x, the engine started to bog down and stall at idle and especially at low speed. After starting, and slowly throttling up, It would bog down and stall. In the same condition, and starting with choke, and quick acceleration, the boat would take off and run smooth to WOT. Slow down to around 1500rpm and it would bog down and quit.

I took the boat again after around two weeks, and it seemed to run fine. I drove the boat through a 5 mph zone at low speed for about 10-15 min. and then started to sputter and quit. Started the engine with choke and punched it, no problem to WOT. Same problem as stated above at low RPM. At slow acceleration, it would quit. Fast acceleration, no problem.

I ran the engine out of the water (with ears) at low RPM and it smoked profusely, bogged down, and quit. Black sludge oozed out of the hub and propeller exhaust. I pulled the plugs and they were wet (but looked pretty clean).

I suspected carbs, so I pulled them (X4) and they looked clean inside. I cleaned/rebuilt them and reinstalled them. I installed new spark plugs with gap to spec.

After completing the work above, I started and ran the engine on land (with ears) for around 5 min. The engine seemed to run well... positive response on the throttle and a limited (normal) amount of smoke and turned the engine off.

After around 20 min., I started the engine again. And again it started sputtering, smoking profusely and bogged down when applying throttle and quit. On a side note, the engine would "kick-in" or run better if I applied choke when It would begin to sputter. The engine starts pretty easy (while choking) but dies pretty quickly after start. Afterwards, there was alot of black oily sludge that oozed out of the propeller exhaust and propeller hub.

I'm not sure where to go next (VRO? decarbing? (which involves VRO disconnect) solenoids?... Can't seem to troubleshoot using the repair manual. Sorry if this post appears lengthy, but I wanted to describe the problem as best as possible. I'm not sure if I may be overlooking something more obvious. Your help as to where to go next is appreciated. Thanks in advance of your response/s or insight to the problem.

 

[Daviet]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Almost sounds like a couple of problems. The sludge and smoke problem sounds like to much oil. Having to use the choke usually indicates a low or restricted fuel flow. Arn't the oil and fuel pump combined in the same unit (VRO).

 

[team shadow]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

I'm having a similar problem except mine is idling fine now and it only acts up after 20 - 30 minutes of hard running. You can see my post on this under 225 HP stalls after 20 minutes.

Heres what I tried today.

I replaced the hose and clamps at the the pulse valve and VRO, also cut hose back and replaced clamps at oil input at VRO. Hooked up separate gas can with 5 gallons of gas and a bottle of Mercury Carb cleaner mixed in and ran the motor several times at the dock today and never did it stall or have idling problems. Figured this would at leat give the carbs and motor a good internal bath and it's running great at dock. I will reconnect fuel line to boat tank and take it out for a test ride tomorrow morning and will try pumping primer bulb if it happens again if that doesn't help I will try putting hose back in gas can and try that.
I too feel this is VRO related but don't understand why it would be fine idling and running hard for 30 minutes then problem would happen. Some people are saying there are rebuild kits and someone else told ne that don't make them any more and that it's better to just replace it. If it comes down to replacing it, I think I will get the Evinrude one that eliminates the oil injection system and not have to worry about whether it's working or not.

 

[jonesg]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Team shadow, start a new thread pleeese, you're causing confusion here.

Back to original post.

Sounds like a fuel leak in the fuel feed lines somewhere.

The fuel pump senses vac from the leak ( fuel seeps out=air leaks in)
and compensates by cycling the pump quicker, that causes extra oil in the mix.

Hitting the choke dumps raw fuel into the manifold and circumvents the problem. so...

Pump the bulb firm and use a flashlight to look for fuel seeping at fuel couplings, especially on the engine around the pump or even leaks on the pump and primer.

 

[tashasdaddy]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

as jonesg, said. also before spending a cent on parts, check the compression and spark, on all 6 cylinders. you want to use a spark tester (auto parts store $10) set tester at 7/16 inch, compression directions here http://forums.iboats.com/showthread.php?t=299680 on a 200 i would like to see 90 psi on each, but most important, that they are withing 10 % of each other.

this will tell you if you have a viable base to work with. if all this is good, then look into fuel deliver, and timing. using old gas is no good either.

do you have a fuel/water separator, change the filter.

 

[team shadow]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Sorry, didn't mean to confuse anyone but I thought the idea was to discuss similar problems and let them know what you have tried or did to fix it.

 

[Boatandfish]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Thanks for the replies. I will follow-up on the suggestions and post my findings.

 

[Boatandfish]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Just wanted to follow-up regarding the problem and troubleshooting progress. Since my last post, I checked the following:

Compression: approximately 130-135psi for all four cylinders.
Spark: Strong spark at 7/16" on all cylinders.

In addition, I ran the engine on 50:1 premix (at home), and the engine seemed to run quite a bit better... smoke seemed about what could be expected. It seemed to run a little rough, but idled pretty well and throttle responded well.

In addition, I opened up the fuel resevoir on the fuel bracket assembly. The needle was pretty caked up with an orange/copper colored (dried putty) type substance and thought that this may be my home run! I replaced the needle, seat and gasket.

After assembly, I reconnected OMS, pumped up the bulb, and inspected all lines. No leaks, and no "hissing" sounds (As per comments by jonesg and other posts that I have read, it appears that VROS/OMS can go haywire due to any vacuum leak on the gas side). And this makes alot of sense.

In addition, I have read that the spark advance (cam roller) on top of the flywheel, should "just touch" the lever/arm in neutral. My engine had a small gap (approximately 3/16") so I adjusted that also.

From cold start, the engine started at the touch of the key. Once again, idled OK (but not great) and with a limited amount of smoke. No stalling and the throttle was responsive for a few minutes, until...

My guess is that the engine burned the fuel in the carbs/fuel reservoir and then came the smoke (lot's of it). Engine still ran OK (but not well) but didn't quit. Throttle was responsive. I ran the engine for approximately 5-10min. On another note: The engine idle increased to around 1500rpm and didn't back off (maybe due to spark advance?). I noticed a small amount of the black oil/residue on the skeg, and a few drops of the stuff on my driveway the next day (but nowhere near the amount that I had before).

So... I am again scratching my head and reaching out to you experts for some input. Thanks again, in advance.

One more thing, do you think it is a good idea to replace the "spring type" clips and zip-ties with stainless hose clamps at all fuel related connections? (even for precautionary measures?)

Thanks again.

 

[Chris1956]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Sometimes air will leak in, but fuel won't leak out. When air leaks, the OMS pump will pump more oil than is necessary.

I would check the entire fuel like for air leaks. Don't forget to check the main strainer under the airbox. It has two seals. Make sure they are in good shape.

 

[Boatandfish]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Thanks for the reply Chris. Strainer/gaskets appear fine (this is also one of the first things I checked after the problem started.

I examined the fuel lines as best as possible and replaced zip ties with hose clamps on a few fuel connections. I started the engine up a few minutes ago in my driveway. Starts right up and runs pretty good (except for tons of smoke).

Any additional advice is appreciated. Thanks.

 

[Fl_Richard]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Run it on a portable tank. That will rule out the boat tank, pickup filter etc...

 

[jonesg]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

ok so spark is good.
compression is great.
You've gone over the fuel system.

Try putting a timing light on each wire to see if its dropping spark when it gets warmed up. Try the spark gap tester when its warmed up too.

also try (carefully) spraying starter fluid around areas that can leak.
Don't go nuts with it, just a spritz and listen.
Listen for a jump in the idle.

Otherwise I'd start testing the powerpack with a peak reading meter.
$62 on ebay.
http://cgi.ebay.com/ebaymotors/Mari...Z230353556405QQptZMotorsQ5fAutomotiveQ5fTools

 

[Boatandfish]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Thanks, as per one of my prior posts, I ran the engine on a portable tank at 50:1 and it ran alot better, with an amount of smoke that I would consider normal.

I spoke to marine mechanic and he asked me what the symptoms/problems are with my engine. All I said was, "It's smoking alot". Without any further questions, he recommended that I replace the OMS and added, "They tend to over-oil, just before they go". Is there any truth to this statement?

Thanks.

 

[Boatandfish]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Thanks jonesg, I was posting a reply to this when you replied. Will do... Thanks

 

[jonesg]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Thanks, as per one of my prior posts, I ran the engine on a portable tank at 50:1 and it ran alot better, with an amount of smoke that I would consider normal.

I spoke to marine mechanic and he asked me what the symptoms/problems are with my engine. All I said was, "It's smoking alot". Without any further questions, he recommended that I replace the OMS and added, "They tend to over-oil, just before they go". Is there any truth to this statement?

Thanks.

yeh but they over oil if the system is drawing air from any leak.
Its easy for the mechanic to throw parts at it when you're paying.!
And they over oil if the system has any fuel line restrictions too.

Pump the fuel bulb up firm , use a good flashlight and watch all the hoses under the hood, look for fuel seeping at junctions. The OMS can leak out the back too, dry the area with paper towels then look for damp areas later.

Also make sure the vac feed for the OMS is good, it has a check valve where it taps into the block for vacuum, make sure thats clear and the hose isn't clogged.

One other thing, a gas restriction will do the same as a gas leak.
Make sure all your lines are big enough, eliminate any extra filters for now.


Watch this,

http://www.youtube.com/watch?v=SEbW-6eOc5I&feature=channel_page

 

[kenmyfam]

Re: 2000 Johnson Ocean Pro - Smoke, Sludge, Low RPM Problem

Just a snippet here.
I know I am not comparing the same pump but when my old VRO pump started to fail it was the fuel side that started to give out and it did over oil my fuel delivery. In saying this I am certainly not telling you not to check for any leaks as I completely agree that this will cause the issues you currently have.
The fuel side is re-buildable (I think) so if all else fails with the leak testing you could whip it apart and inspect the diaphram.