Weird Motor Issue

[5 Dollar Fishing Game]

My 1995 Johnson 70 two stroke did something strange today. Took my wife and daughter to the lake today. No fishing. Just cruising around.

We ran wide open for about 5 minutes 3 different times. Then all of a sudden it started bogging like it was running out of gas. Lurched about 3 times. I backed off the throttle, and slowed it down to about half. Did fine for a minute. Then the same. Then I put it to the floor to see if it would do anything. The motor seemed like it was idling. Then it cut off.

I checked the tank. Half full. We sat in the middle of the lake and are for about five minutes. Let the mirror relax. Cracked it up. Perfect. Ran wide open rest of the day at different times. No issues. This never happened before since January when I had it.

Pee hole was working fun. New NGK plugs about a month ago. Fuel filter replaced in January.

Could the filter have been stopped up by something or does it need replacing again? I use the boat about once a week.

Also, I have been using the same fuel and oil mix.

Thanks!

Joe

[Smokinal]

May have just been some crud sucked up in a jet or passage. Hard to tell until it happens again on a regular basis.

[5 Dollar Fishing Game]

That sounds like a possibility. The motor is usually extremely smooth non issue. I'm glad it stopped after that. :-)

[Way2slow]

Hard to say, could have been a fuel delivery problem, fuel pump, anti-siphon valve in tank sticking, water in the fuel, etc. Several things along that line can cause similar problem.

Then it could have been trying to go into limp home mode, if that motor has one. Not sure exactly when OMC added that and what models have it. When it goes into limp home, the ECU will not let the motor turn more than 2,000 rpm. This can be cause by an oil sensor if the VRO is still connected, or temp sensor.

Then there is the ECU itself.

Those random/intermittent problems are the worst of all to try and fix. Motors are pretty easy to trouble shoot when it's broke, but when it screws up, then goes back to working normal, it's hard to fix/find what's broke when it's running perfect.

I even had a vent hose from the tank to the filler cause one to start surging like that. Took me a while to find that one. The hose had a large bow in it from the filler to the tank and gas would get in it and it would act like a P-trap on a drain, and wouldn't let the tank get air.

[5 Dollar Fishing Game]

It gradually died out like it was losing fuel. I'm hoping it just sucked up some junk. :-)

[Fishing Rhino]

When it does that, squeeze the primer bulb to see if it's hard.

 

For seemingly no reason I have that problem from time to time when getting the boat up on plane.  It will accelerate then die down.  Could be some of the things Way2slow said, or an air leak in the fuel line which prevents the fuel pump from picking up fuel.

 

It has done that since it was new.  Brought it back to BPS and they hooked it up to the computer and did not find anything.  So what I do is to squeeze the primer bulb before heading out onto the water.  As Way2slow said, the intermittent problems are the most difficult to solve. 

 

I have a friend whose boat did the same thing.  We were both out on the same lake so he called me in case he needed a tow back to the dock.

 

When I got to him I checked his primer bulb, and sure enough, it was soft.  About five or six squeezes and he was back in business.

 

This is my fifth year with the boat.  At the end of this year I'll replace all the components in the fuel line, and see what that does.

[Fisher-O-men]

My Johnson had a similar problem.  It would take off great from the dock and run fine for about 1 minute, at which point it would bog and fall off plane.  I would let it idle for about a minute or two and then take off again.  Many days that would be the last time it would happen. Other days it would happen a couple more times.  Want to know what was causing it?  Ah, the suspense!

 

Power Packs!  Not cheap, but it completely fixed the problem.

[5 Dollar Fishing Game]

Im hoping it just stays normal lol. Power packs sound expensive. Are they the 3 coil packs with the spark plug wires attached to them? Almost like coil packs on a newer model car.

[Way2slow]

No, look at the coils and you will see the spark plug wire and a smaller wire connected to it. Follow that smaller wire to the box it's coming out of, that's the ECU/power pack, and yes the are not cheap.

The problem is, it's not something you just want to replace without going through all the proper trouble shooting first, and that's not something you can do yourself. The other bad part, the only way to really test it is to replace it.

[tomustang]

When it does that, squeeze the primer bulb to see if it's hard.

 

For seemingly no reason I have that problem from time to time when getting the boat up on plane.  It will accelerate then die down.  Could be some of the things Way2slow said, or an air leak in the fuel line which prevents the fuel pump from picking up fuel.

 

It has done that since it was new.  Brought it back to BPS and they hooked it up to the computer and did not find anything.  So what I do is to squeeze the primer bulb before heading out onto the water.  As Way2slow said, the intermittent problems are the most difficult to solve. 

 

I have a friend whose boat did the same thing.  We were both out on the same lake so he called me in case he needed a tow back to the dock.

 

When I got to him I checked his primer bulb, and sure enough, it was soft.  About five or six squeezes and he was back in business.

 

This is my fifth year with the boat.  At the end of this year I'll replace all the components in the fuel line, and see what that does.

If you have a merc it's most likely the primer bulb not holding fuel (leaking)

Merc had a bad batch of them come out years ago

[Slade House]

ALL BOATS PRE-2005 have fuel lines that are not designed to handle ethanol blended fuel.  Had this exact thing happen to me, most likely its the fuel line inner linning sloughing off and clogging up your filter.  Remember that all boats  PRE-2005 have fuel lines (specifically the one with the bulb attached to it) that are not at all rated for ethanol blended fuel.  what happens (happened on mine) is that the the inner lining inside that main fuel line starts to break apart into little orange plastic bits of the inner lining from the ethanol blend.  

 

This will clog all of the lines up until your fuel filter.  those little bits of inner lining have no clogged up your fuel filter to the point your motor will bog down cause no fuel is getting past it.  It may work briefly for a minute or 2 and then wham it just bogs down and dies.  Sometimes it may work all day and then all of sudden a little piece of inner lining plastic just clogs it all up again.  

easy fix and very cheap too.  

 

What you need to do is take apart all of the fuel lines leading up to the filter , take an air compressor and blow the crap out of the small lines inside the motor , replace the main line and squeze bulbs, replace the filter.   ,.  ALSO you may have to take apart your fuel mebrane and get bits out of that as well (delicaltely) DO NOT DO WHAT I DID AND PUT THE FUEL FILTER BACK ON BACKWARDS.  that will only cause the little bits to clog up your carbs , which happened to me and wasnt that hard to fix.  

 

Bottom line is it aint a powerpack issue, it aint eletrical. its fuel .  

[Slade House]

if you think about it , you gas the motor , goes for a minute then bogs down and dies .  once it dies those little bits fall back down , so you gas it up again and those bits clog it all up again , dies and repeats.  if you have not changed out your  main fuel line and your boat is 2005 and before , you need to now. 

[Way2slow]

It sure would be nice is people posted fact and not what they think they know.

 

Maybe if you read this article from Boat US it will help you with some of your facts.  http://www.boatus.com/seaworthy/magazine/2012/april/EthanolAndOlderEngines.asp

 

Also, be sure to take note of this sentence in it.  Since 1984, all hoses approved for marine use in gas engines have had to be built to this standard and hoses marked “SAE J1527” are capable of withstanding ethanol blends.

 

Granted, they all didn't convert immediately to J1527 hoses and there was some learning curve with gaskets etc, but by the early to mid 90's, most all had it worked out.

Those orange flakes/bits in the fuel line are most likely not the fuel line breaking down, it's where the gas has been left sitting in the fuel lines and broke down from age, leaving that varnish film gasoline will leave. The ethanol dissolves that stuff in the tanks and fuel lines and makes it look like the fuel line is coming apart. Ethanol normally dries the fuel lines out and makes them extremely brittle where they crack and break or can turn them to mush, making the hoses soft and gummy.

By the way, I have about a 1/2 dozen power packs that caused similar problems that apparently couldn't not have possibly been bad, but for some strange reason, replacing them fixed the problem.

[Snakehead Whisperer]

A friend of mine had this exact same problem last week while we were out on the lake. His is an '89 Evinrude. 

 

We took the boat back to his place, and checked everything. Pulled the carbs apart, cleaned/rebuilt them, checked the pressure on the fuel pump (ok) and checked all ignition parts and tank/fuel lines. Motor ran good after all of this on the muffs, so we took it back out and it bogged down and died again. We were stumped. Motor would run alright if I squeezed the primer bulb as he drove.

 

Once we got the boat back in the driveway I started looking at everything again. I finally decided to take the fuel hose off of the fuel fitting at the motor, and it's a good thing I did. The hose clamp that was on the fuel hose had pinched the barbed part of the fitting so that it was restricting the fuel. Bought a replacement fitting for $4.99 and all is well. 

 

My point is to not overlook the small stuff when diagnosing something like this. I've seen old primer bulbs do this too. 

[5 Dollar Fishing Game]

Very true!!!! :-)

[fishnkamp]

That statement that all fuel lines boat manufactures used after 1984 are supposed to be ethanol safe is bogus.  I have a friend with a 2001 210 ProCraft powered by a Mercury 225 OptiMax.  This exact problem reared its ugly head just this summer on his boat.  I spoke with my local dealer ( he sold both Ranger and ProCraft) to get his advice.  I have run Mercury motors on nine of my last 10 boats. This list includes the 1998 ProCraft 20 footer I bought from him new.  Unfortunately I had no experience with the Opti motors.  He told me that his service department has seen more fuel\fuel line issues within the last three years than any other type of issues.  They replace all of the fuel lines from the tank to the engine, the smaller on engine lines they take off and blow out.  Then they replace the small mechanical pumps, open the filter/pump housing, replace the filter, clean out the housing, clean up the internal float assembly and clean and test the electrical pumps. Often they have to replace the electrical pump because they get burned out.  All my friend knew was his engine would run good, then shut down, or upon restarting after fishing the engine would be hard to start or shut down.  He would have to pump the primer bulb again to restart it. The junk was hanging up the float assembly so the electrical pressure pump was starving for fuel till he reprimed the system manually. That is what we did.  We replaced the lines and filter.  Then cleaned out the housing and fuel jet/ float assembly,tested the electrical pump (thankfully ours was good) and reassembled it again.  Things ran fine after that.  I also recommend you do as I do always add Startron fuel additive in with every fill up of your fuel tank.  Mercury Marine actually recommends either their fuel treatment or Startron. All of the troubleshooting advice given before me still goes, do not over look the little things, but I would start by opening up your filter and inspecting the inside material for debris, this can clue you in fast.

[Snakehead Whisperer]

Joe

Did you ever figure this out?

[5 Dollar Fishing Game]

Just started using ethanol free gas. Fixed :-)

[Way2slow]

Well, if that's all you did, you can remove the "fixed" at the end.  The problem just has not shown back up again "yet".  Changing to ethanol free gas does not "fix" anything.

[5 Dollar Fishing Game]

Optimism!!!

[5 Dollar Fishing Game]

Well, if that's all you did, you can remove the "fixed" at the end. The problem just has not shown back up again "yet". Changing to ethanol free gas does not "fix" anything.

Sure it can. If the 1989-1995 engine configuration doesn't work well with the ethanol in the mixture then it can cause surging. Also, I've run the boat many times since the change and not only has the issue stayed gone, but it runs better. Try diesel fuel in a car that calls for gas and run it. Then change back to gasoline (if it still runs) and see if the change works. I've talked to guys at the tourney Ramos and all of them concur with the same issue and resolution. The ethanol powered fuel here can cause intermittent plug fouling and other fuel burning issues.

[WIGuide]

Well, if that's all you did, you can remove the "fixed" at the end.  The problem just has not shown back up again "yet".  Changing to ethanol free gas does not "fix" anything.

I love how he continues to ignore/disagree with one of if not the most knowledgeable BR members when it comes to outboards....as Bill Engvall would say, Here's your sign!

[5 Dollar Fishing Game]

I love how he continues to ignore/disagree with one of if not the most knowledgeable BR members when it comes to outboards....as Bill Engvall would say, Here's your sign!

And I'm not knowledgable?? How do you know who I talked to here in NC at engine repair shops? How do you know that I myself have not been working on motors for a few dozen years? How do you know what I know? Here's YOUR sign.

I also don't appreciate the way you're talking about me. You need to learn some respect.