1990 Rude 150 VRO skipping

[jaurora]

Hello All,

Im back for another boating season.

I am hoping someone may have a thought on what my issue may be. I have had this motor for a couple of years and it has always been flawless up until the end of the season last year.

I got gas at a dock and thought water was my cause but I am now starting to think different as I had run a few tanks through since then. I have a water seperator as well and replaced the element this year and filled the boat up with fresh gas and I am still witnessing the same issue.

Motor has good even compression on all 6, carbs have been pulled twice and all the jets were pulled and cleaned.

The motor starts up just fine and idles well. Its when I really give it the juice, Id say from half throttle to full throttle, the motor skips, its like the motor cuts out for a second and kicks back in. It is a constant stop and go feeling. Just a lot of on and off hesitation, it happens when the motor is hot or cold and only seems to happen at mid to full throttle as mentioned.

I thought about the regualtor as I replaced that a few years back, my fish finder has a volt reading on it and at a high RPM it was speratic, 13 - 14.5 it showed no consistancy just alot of fluctuation.

The coils and wires seem to be in good shape with no cracks. I am pretty much stumped on this one and in high hopes someone came across this situation in the past.

Thank you in advance for all of your help.

 

[mulishatroop940]

Re: 1990 Rude 150 VRO skipping

check ur reeds u might have a cracked or broken one

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Will do, I see alot of people having the same thing happeneing but they are aiming towards the clutch dog, which had me thinking but if the motor is in neutral and I raise the idel lever she still skips and somewhat pops.

 

[rodneyjanssen]

Re: 1990 Rude 150 VRO skipping

Check the plug wires to make sure there are no hair line cracks causing them to misfire. Pull the plug wire from the spark plug and put a slight bend in all areas of the wire to try to expose the crack. Or a possible air leak in the fuel system. Is the motor smoking more than normal?

 

[jonesg]

Re: 1990 Rude 150 VRO skipping

Can you examine the stator without pulling the flywheel?
It might be melting.

Another thing to try is a timing light when it starts skipping, see if it drops spark and which cylinder/s ( or all of them.)

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Check the plug wires to make sure there are no hair line cracks causing them to misfire. Pull the plug wire from the spark plug and put a slight bend in all areas of the wire to try to expose the crack. Or a possible air leak in the fuel system. Is the motor smoking more than normal?

As a matter of fact the motor has been smoking more than normal. What I did notice is I think there may be a small leak in the primer ball, wonder what the chance are of that being the culprit.

So you think it could be a possable air leak? I spoke with my uncle yesterday and told him what was happening, first think he mentioned was a possible air leak.

I will replace the primer and double check everything else.

 

[CharlieB]

Re: 1990 Rude 150 VRO skipping

If it is an air leak into the fuel system it should respond to pumping the primer while under way, If that makes an improvement then dig into your fuel system more, line and pump.

If no change then you're still testing.

I've seen a couple motors act as if they 'coughed' but it turned out that the shift cable adjustment was not holding it in gear, the dogs would 'jump' a notch. The condition only showed at near WOT, and never in reverse.

Test WOT in reverse, if no fault try readjusting the shift cable.

Note, it the cable adjustment cures it, then plan on replacing forward gear and the shift slider in the future.

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Weel, I replaced the primer ball as well as double checked all gas lines, even if I pump the ball underway I still see no effect.

I did more research on the site and I do not think that it has to do with the shift cables or the clutch dog, reason for that is the motor will still sneeze/caugh while in neutral and when the motor is started up. I think my next step will be pulling the carbs one more time to see if that could be one of my main problems.

I guess while I have the carbs off I can check the reeds as well. Thank you for your input and I will post my findings when I get there.

 

[Beernutz]

Re: 1990 Rude 150 VRO skipping

VRO pump.

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

VRO pump.

Why do you say the VRO pump? why would that cause it to sneeze and cough at mid to high RPM's?

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

well here is where i stand.

i pulled all the carbs, cleaned them all, checked all the reeds and everything is spotless. i checked for spark and i have good spark on all cylinders. I went for another test run and the same old tory, plenty of power to get it on plane but still does not want to go wide open. the motor still coughs as it did from the get go. I remeber having this problem at the end of last year and I thought it was water in the gas. pulled te carbs twice, 2 tanks of fuel, new seperator, new gas lines and still this issue. Someone said the VRO pump. could this be the culprit? i noticed a clicking noise coming from the pump. This was the first time i have heard it. it seems like it clicks every thirty seconds to a minute. the funny thing is i heard it click even when the motor was off. I am stating to runout of options. thoughts on what i may try next?

thank you,
J

 

[CharlieB]

Re: 1990 Rude 150 VRO skipping

Test again, WOT in REVERSE

Did it 'cough' or feel like it 'missed'?

If NO, then readjust the shift cable trunion TWO TURNS away from Forward gear, giving a slight bias towards Forward and a little pressure to hold it into Forward.

Retest WOT in Forward gear.

Any change?

If better, continue biasing the cable and start saving for a new forward gear and shift slider.

 

[TLL]

Re: 1990 Rude 150 VRO skipping

The clicking from the VRO pump is normal. So you have said cough, sneeze, skip. We really need to identify what the sound is. Cough, sneeze- fuel starvation, Clunk- shifting problem, Sounds like you turned the key off for a millisecond, like one spark plug didn't fire- ignition, like a intermittent coil when at high speed.

 

[rokhd]

Re: 1990 Rude 150 VRO skipping

I have a 2000 johnson 90 horse that was doing what you describe. I replaced the OMS (VRO) pump and it still did the same thing. It ended up being the small fuel vapor pump on top of the OMS pump. It had a leak. After I replaced it, it ran fine and the excessive smoking quit. This may or may not help you.

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Thank you for the information.

It is not the shift cable as it does its thing in nuetral, forward and reverse but I will try and adjust the shif cable.

One thing I noticed after I pulled the carbs again yesterday, I primed the ball until they filled up, I had a very hard time getting the motor to start/run at idle. it kept wanting to stall out on me, until the (cough or sneeze) sounded like a exhaust pop and boom, she was running at a good idle speed with more smoke than normal. took it for a test run and still the same old hesitant on and off feeling at mid to full throttle.

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Just out of curiosity, what does item 10 (vaccume switch) do?

 

[elhombre]

Re: 1990 Rude 150 VRO skipping

Just out of curiosity, what does item 10 (vaccume switch) do?

Lean/no fuel alarm

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Well here is an update.

I rplaced all the plugs, checked for spark, checked for cracks in the wires, everything was good. Went through the manual, checked the stator, regulator and power packs and all checked out as good.

After another test run it continued to do the same thing, but this time I noticed that when I ran the motor a WOT and kicked it into neutral, i heard a pressure release noise coming from the motor, it was a lout quick hiss. after further investigation i found that the house from the VRO, engine crank case fitting was blowing bursts of air from WOT to neutral.

Wow was I happy, took it back to the dock, pulled it apart to find 2 of the plastic hose clips were snapped. I replaced those and was keeping my fingers crossed on the next test run.

Well i was dissapointed. It seemed alot better at WOT but not where it should be and now it skips and coughs at a low RPM. I ran out of light so I am going to do some more digging tonight. I think my problem is somewhere in that general area. will keep it posted on my findings.

 

[jonesg]

Re: 1990 Rude 150 VRO skipping

Good detective work will reveal the culprit, sounds like you're on the trail.

Smoking at idle can be an air leak in the fuel supply causing the VRO to cycle quicker than normal. Just another thing you can check out quickly.

Watch this,
http://www.youtube.com/watch?v=SEbW-6eOc5I

 

[jaurora]

Re: 1990 Rude 150 VRO skipping

Well took everything apart, all new clamps, checked all of the lines and there are no leaks and still runs like crap.

One strange thing that I have noticed is a startup, not sure if this is normal or not but I find it to be quite odd.

My boat is in a slip when the motor is down and started, it takes about 30 - 45 seconds before the exhaust starts to come out fromt he prop area and bubble in the water. Is this normal?