Could this really just be vapor lock on a Johnson/Zuke 140??

Swampsquash · November 2013

03 johnson zuke 140hp

I have:

Replaced plugs
changed oil
oil filter
had injectors pro cleaned
changed ALL fuel lines and filters
Installed a brand new fuel water seperator
decarbed
new thermostat
New water pump

I have a vapor lock issues....But I am trying to figure out if its only vapor lock or combination of vapor lock and something larger. My motor runs great on the first start of the day...I feel like I could run all day without any issues.

Couple things I notice about the motor. After a long run and pulling it into neutral, the outboard will let water vapor/steam out of the exhaust hole next to the pee hole. The vapor maybe lasts 3-5 seconds and then you see no exhaust coming out at all.

Certain times on a restart (has happened once or twice in last month) it will blow a tiny bit of whiteish smoke for a second or 2. Not alot but enough to notice. It NEVER smokes on the initial cold startup. And like I said its very rare that it ever smokes anyway.

Ok so onto my vapor lock. It seems to lock up all the time. It doesn't matter if the ambient air temp is hot or cold (yesterday it was 82) I have heard most people have this problem in the mid to high 90's. It will basically happen between 10-30 seconds into "getting on plane". And it will hiccup and basically I pull it to neutral and the motor is still running (Most of the time) it has shut off once for twice. Once I idle it and hand pump the fuel in....it gets on plane and runs great until i shut it down.

I have idled 10 mins before shutting down. I have idled 5-10 minutes before starting.....no matter how long I idle it seems to vapor lock.

I have read TONS of info on this and nobody speaks of a true fix. Does it sound like vapor lock? Anything else?

How do I FIX it? Do I need to install a FRD-1 fuel pump?

I also checked the compression today and it was : 190, 183, 182, 190

So I don't think its blowing up lol.

Thanks everyone in advice.....This surging and sudden stopping isn't safe and I need to solve this.

kanaka · November 2013

Cheapest, fastest fix is to replace the quick disconnect on the fuel line.

Next, look for a birds nest in the intake area.

Your symptoms are exactly like my fishing buddys problems, the above were the combined fixes.

Swampsquash · November 2013

kanaka wrote: »

Cheapest, fastest fix is to replace the quick disconnect on the fuel line.

Next, look for a birds nest in the intake area.

Your symptoms are exactly like my fishing buddys problems, the above were the combined fixes.

I had the intake off when replacing the fuel lines...I cleaned the throttle body really well....I didnt see any birds nests...was it inside the "pipes"?

Quick disconnect? Ie the suzuki fuel connection plug device. Plugs into two prongs at outboard cowling? I did replace it with a new one and the fuel lines are new.

Does that quick connect device restrict fuel flow?

kmagnuss · November 2013

I had a motor that was doing similar things that I was chasing my tail on... after I replaced all the fuel lines in the boat (except the line from the fuel bulb to the motor) I finally took apart the fuel bulb and realized that the plastic liner inside my fuel line had bunched all up when it was shoved on the fuel bulb, which was restricting fuel flow. It only would do it on WOT runs of a certain length of time... but would run at part throttle all day.

SCFD rtrd. · November 2013

If you pump the bulb and that fixes the problem, sounds like a fuel restriction. One of the easiest and quickest things to do is replace the primer bulb then remove the anti-siphon valve on top of the fuel tank.

Swampsquash · November 2013

SCFD rtrd. wrote: »

If you pump the bulb and that fixes the problem, sounds like a fuel restriction. One of the easiest and quickest things to do is replace the primer bulb then remove the anti-siphon valve on top of the fuel tank.

I forgot to mention, but I replaced all fuel hoses(bulb too) and the anti-siphon as well

cookin out · November 2013

I have had something similar....after idling for a while sometimes one of my engines will shut down. I really am not positive what has happened but I believe I have had some air leaks on the bowl of my fuel water seperator and it creates something similar to a vapor lock.
The engine is starved for fuel. After pumping the bulb a few times it usually fixes itself....

Every time I change the fuel water seperator I notice the o ring has swollen quite a bit and this might be my issue.....
Maybe try putting some sort of tape around the joint of the bowl and the filter and see if that corrects the issue..

Swampsquash · November 2013

I actually have a filter without a bowl right now....it came with the unit, since I had to buy it new as the boat never had a fuel/water separator until I installed one, just figured I would put a filter with a bowl on next time.

kanaka · November 2013

Motor in my example is a 140 (?) Johnson 4 stroke. Intake tract starts at the rear of the cowling, goes to the front where it mates up to actual intake housing mounted on the motor.
A wren started building a nest in there and it was sucked down the air intake enough at WFO to block off air. ECM didn't like that so engine dropped to idle. No intake pressure so nest got uncompressed and air flow went back to normal.

If the quick disconnect has bad o rings or is sloppy, that's a place for air to be sucked into the fuel line. Just because its sucking air in doesn't mean it'll be leaking fuel out. Double check/tighten all your clamps.

What brand fuel line did you use?

Just realized that this is a ongoing problem for you from previous post. Need DETAILED information if you want help.

What brand bulb, fuel line, and did the problems start AFTER the water separator was installed?

Swampsquash · November 2013

kanaka wrote: »

Motor in my example is a 140 (?) Johnson 4 stroke. Intake tract starts at the rear of the cowling, goes to the front where it mates up to actual intake housing mounted on the motor.
A wren started building a nest in there and it was sucked down the air intake enough at WFO to block off air. ECM didn't like that so engine dropped to idle. No intake pressure so nest got uncompressed and air flow went back to normal.

If the quick disconnect has bad o rings or is sloppy, that's a place for air to be sucked into the fuel line. Just because its sucking air in doesn't mean it'll be leaking fuel out. Double check/tighten all your clamps.

What brand fuel line did you use?

Just realized that this is a ongoing problem for you from previous post. Need DETAILED information if you want help.

What brand bulb, fuel line, and did the problems start AFTER the water separator was installed?

Yes I have a ongoing problem....My last post was a completely different issue(electrical wiring) and it has been solved. Since this is a different issue I started a different post. I am pretty sure I have given nothing but DETAILED information to this point.

I do have some "old" pinestraw etc in the bottom of the cowling, etc. Not alot couple tiny little strands. Maybe that could have been a bird nest of some sort. I will dig a bit deeper in the light tomorrow and see if anything in is the "tubes" after the throttle body. I will also check out the air box.

The hose I used in the boat side of things is shields marine ethanol proof fuel line my local marine store recommended. The hose on the inside of the motor is now yamaha brand reinforced hose (has the rope threads in it for strength). The bulb is also one they recommended and have had success with. I am not sure of the bulb brand.

The quick disconnect is brand new and feels very solid. But you know how it goes, even new stuff fails.

Ketch-up · November 2013

I am having alot of the same issues after putting a fuel-water separater on my Evinrude 150. I was in a hurry when I installed it and did not put pipe dope on the threads. Also make sure your have the bulb on an upward slope pointing at the engine so the check valve will work properly. Just me .02 worth.

Swampsquash · November 2013

Ketch-up wrote: »

I am having alot of the same issues after putting a fuel-water separater on my Evinrude 150. I was in a hurry when I installed it and did not put pipe dope on the threads. Also make sure your have the bulb on an upward slope pointing at the engine so the check valve will work properly. Just me .02 worth.

hmmm Yeah I really don't think thats my problem....I used aviation formagasket and have them glued in nicely.

I did take apart the low pressure pump today to do a inspection. Everything looks perfect....unfort lol I am really hoping it was my problem......the diaprahm looks great and everything else looks pretty much like I feel it should. Unless the springs are worn out, I think its ok. I really don't know. I have the new one with the V at the end of the part number on its way. I'm not sure its a special pump to fix the vapor lock issue, but who knows.

Its a never ending debacle!

Ketch-up · November 2013

I am really finding out what boat stands for with only being able to use mine a few times a year.
B-BREAK
O-OUT
A-ANOTHER
T-THOUSAND

Swampsquash · November 2013

Ketch-up wrote: »

I am really finding out what boat stands for with only being able to use mine a few times a year.
B-BREAK
O-OUT
A-ANOTHER
T-THOUSAND

haha for sure.....If I couldn't do maintenance myself, I would be broke......and wouldn't be able to own a boat.

Ketch-up · November 2013

Me either. check to make sure the filter is screwed on really tight. Just a thought.

kanaka · November 2013

Just wanted to make sure you were using the "good stuff" not the generic for the fuel delivery stuff.

How is your gas tank vented? Could be pulling a vacuum.

When you are squeezing the bulb to restart, is it flat? No fuel in it? Or does it look normal but no fuel in it and you have to pump it to get fuel back in till its hard?

bmoody · November 2013

I'm a yami guy so bear with me...
Does this engine have a VST?
Does this engine have multiple fuel pumps?

On a yami those could be issues with your symptoms.

Swampsquash · November 2013

It has a perko dual vent/fill cap/device. I really don't think thats the issue.

the bulb isn't flat its def normal but had very little fuel in it.....Takes 5 or so good squeezes to make it firm again.

It has a high pressure/VST like system....I have cleaned that out and replaced all the filters. I just replaced the low pressure pump....unfort I can't test it out tomorrow, because the weather isn't cooperating.

kanaka · November 2013

Swampsquash wrote: »

It has a perko dual vent/fill cap/device. I really don't think thats the issue.

the bulb isn't flat its def normal but had very little fuel in it.....Takes 5 or so good squeezes to make it firm again.

It has a high pressure/VST like system....I have cleaned that out and replaced all the filters. I just replaced the low pressure pump....unfort I can't test it out tomorrow, because the weather isn't cooperating.

Since there was little fuel in it, that means there's an air leak into the fuel line BEFORE the bulb. The design of the bulb won't let air back downstream from the motor end into the bulb. At least for a day or so.
It's troubleshooting stuff like this that'll make you start pulling your hair out....

abovebored · November 2013

Alternative definition: B-broken O-or A-about T-to

FLCoyote · November 2013

I was having similar problems and it looks like you've already done some of the things I had done to correct them. First and foremost my non-ethanol resistant fuel lines disentergrated from the inside and intermittently restricted fuel flow and also clogged the internal VST filter. End result was all new fuel lines and a new VST filter. Next issue was my main wiring harness somehow got contaminated and started corroding causing intermittent engine missing and not going under 2000 RPMs. That causes a shifting safety to kick in and you can't shift into gear. I have a Yamaha 90 HP F90 and I think I take pretty good care of it maintenance wise. Since 2005, I've spent over $7000 in assorted maintenance costs. I once owned an 85 HP force for 11 years and had one breakdown that cost me $85. Everyone told me that the Force was a piece of junk and only good for an anchor. At the rate I'm going I will have spent around $11.0K in 11 years keeping the hi-tech F90 in fishing condition. I don't know if $1.0K a year is considered average, but it seems excessive to me. In last month had lower unit replaced and tilt and trim motor rebuilt at cost of$1480. Guess "Break out another thousand" applies in my case. "Rant over".

FLCoyote

Could this really just be vapor lock on a Johnson/Zuke 140??

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