1996 130HP Evinrude

[svan]

Hello All,
My Engine Idles Fine, starts up every time I turn the key But when I get over 2 grand in rpm it will stutter, then Bog down until I pull back the throttle.
I tried squeezing the the fuel hose bulb when it would act up and it makes a difference, smooths out and continues like it should for a minute. After Replacing the fuel pick-up tube, anti-siphon valve, and new fuel line including the bulb (BRP Brand) should I go after the VRO Fuel Pump Next?
Thanks in advance for your wisdom.
Scott

 

[jimmbo]

Over 2 grand, on the water and in gear, or just revving it in neutral on the Muffs?
Is the fuel Filter clear? Are the Carbs clean? Is the sync between the carbs correct, as well as the sync between the Carbs and Spark?
Checking the Compression, and checking that the Ignition System can produce a Spark that can jump a 3/8" Gap, would also be a good Idea.

 

[Clayshooter56]

Hi Svan, will look forward to your response to Jimmbo. I have the 1996, 90 Hp model, I went through a similar ordeal, rebuilding carbs, deleting the VRO, replacing check valve, only to discover that the relatively new grey marine grade fuel line liner had collapsed.

 

[ct1762@gmail.com]

Hello All,
My Engine Idles Fine, starts up every time I turn the key But when I get over 2 grand in rpm it will stutter, then Bog down until I pull back the throttle.
I tried squeezing the the fuel hose bulb when it would act up and it makes a difference, smooths out and continues like it should for a minute. After Replacing the fuel pick-up tube, anti-siphon valve, and new fuel line including the bulb (BRP Brand) should I go after the VRO Fuel Pump Next?
Thanks in advance for your wisdom.
Scott

#1 is to make darn sure its not overheating and your overheat alarm works.

 

[svan]

Over 2 grand, on the water and in gear, or just revving it in neutral on the Muffs?
Is the fuel Filter clear? Are the Carbs clean? Is the sync between the carbs correct, as well as the sync between the Carbs and Spark?
Checking the Compression, and checking that the Ignition System can produce a Spark that can jump a 3/8" Gap, would also be a good Idea.

hey Jimmbo,
I had this problem for the last 2 years. I have spark to all 4 piston. 118, 118, 120, 120 compression on the 4 cylinders.
My overtemp horn works, I did not check the thermostats. I replaced the power pack Sept. Of 2020. I also rebuilt all 4 carburetors Sept. 2020.
I rebuilt the vro pump at that time also.
Everything I rebuilt
Or replaced was after emptying the fuel tank and replacing the fuel line from the tank to the engine including primer bulb.
This year when I removed the fuel filter the inner part of the hose was collapsed/ melted. So I bought BRP fuel line and bulb, then went after the the pick-up tube and anti-syphon valve(which there was not one installed).
So last night I removed the Fuel pump Vro and disassembled it. It looks fine, no tears or blemishes on the diaphragm.
As far as cleaning the carbs. This year no, I have not "cleaned" the carbs but I am thinking of removing them again and seeing if the internal fuel liner got into the float bowls.
On the muffs the engine runs great but I usually don't advance the throttle too high.
This happens with the boat in the water, not all the time. It happens randomly once I'm up on plane.
Thanks for replying

 

[svan]

#1 is to make darn sure its not overheating and your overheat alarm works.

Yes Sir, the Alarm works but I have not checked the thermostats.

 

[svan]

Hi Svan, will look forward to your response to Jimmbo. I have the 1996, 90 Hp model, I went through a similar ordeal, rebuilding carbs, deleting the VRO, replacing check valve, only to discover that the relatively new grey marine grade fuel line liner had collapsed.

Hey ClayShooter.
My fuel line did the same... I change the line and bulb every year. Getting to be expensive in rubber tubes every year!

 

[svan]

Hey ClayShooter.
My fuel line did the same... I change the line and bulb every year. Getting to be expensive in rubber tubes every year!

I have a new problem now. I took apart my vro pump. And the oil piston seal is split. How do you like not having the oil tank, and vro pump?

 

[racerone]

There may be issues with crankcase compression.----Perhaps a broken sealing ring on the crankshaft.

 

[jimmbo]

Hello All,
My Engine Idles Fine, starts up every time I turn the key But when I get over 2 grand in rpm it will stutter, then Bog down until I pull back the throttle.
I tried squeezing the the fuel hose bulb when it would act up and it makes a difference, smooths out and continues like it should for a minute.

That makes it sound like a Fuel Delivery Problem.
Does the fuel line run directly from the Tank to the Fuel/VRO pump, or are there quick connectors to at the Tank and Engine? if so, have you ever tried running the Engine bypassing the Connector?

Have you drained the carb bowls? A bit of Fuel Line Debris(though it should have been caught by the screens) may occasionally block the Main Jet. Water, if there is enough of it could do the same.

 

[svan]

That makes it sound like a Fuel Delivery Problem.
Does the fuel line run directly from the Tank to the Fuel/VRO pump, or are there quick connectors to at the Tank and Engine? if so, have you ever tried running the Engine bypassing the Connector?

Have you drained the carb bowls? A bit of Fuel Line Debris(though it should have been caught by the screens) may occasionally block the Main Jet. Water, if there is enough of it could do the same.

Jimmbo,
Last year I added a water fuel seperator in case. I had water in the fuel tank or "bad" gas. When I replaced the fuel line this year I bypassed that and the fuel filter near the pump so right now I am running directly from tank fitting to fuel pump in.
Carb bowl drain would be next. I am mad at myself for dis-assembling the vro pump. I am an Aircraft mechanic, have worked on jets for 38 years now and have worked on everything I have owned since my first mini bike at 10 years old.
I have done regular maintenance on this engine for a while but I am not the original owner.
Thanks for your Help. I'll keep you all posted

 

[svan]

There may be issues with crankcase compression.----Perhaps a broken sealing ring on the crankshaft.

ipostedi have thought about that as well. I have not replaced that hose. It looks to be original (1996) maybe I will look closer at that too.
Thanks.

 

[ct1762@gmail.com]

ipostedi have thought about that as well. I have not replaced that hose. It looks to be original (1996) maybe I will look closer at that too.
Thanks.

"looking closer" at sealing rings requires a complete powerhead teardown. might as well send the block out and get it bored for a complete rebuild at that point.

 

[ct1762@gmail.com]

Yes Sir, the Alarm works but I have not checked the thermostats.

when you say "bogs down until i back off" does that mean it clears itself out and is fine at full throttle? or stays bogged? if it clears itself out id say its most certainly a carb issue.

 

[svan]

when you say "bogs down until i back off" does that mean it clears itself out and is fine at full throttle? or stays bogged? if it clears itself out id say its most certainly a carb issue.

It will clear itself once I pull it back to idle and let the boat come off plane.
I will checking the carbs this week. Currently not home to work on it.
Thanks,
Scott

 

[svan]

"looking closer" at sealing rings requires a complete powerhead teardown. might as well send the block out and get it bored for a complete rebuild at that point.

CT, I just re-read this reply, sorry I am talking about the crankcase fitting and line that connects to the fuel pump. I was thinking that maybe the case tube or fitting or "seal" (o-ring)
For the fitting might be bad causing the fuel pump to not have sufficient
Vacuum. I have not done a vacuum check as I must have lent my gauge to one of my buddies before I moved 850 miles and never got it back!
Honestly this is the first time in 17 years I had looked for it.
Sorry for any confusion, and thank you for any thoughts you have.

 

[racerone]

The crankshaft has six sealing rings on it to separate the four crankcases.-----There have been some issues with them.

 

[svan]

Thanks racerone, if the carburetors are clean of debris then, maybe I will have to go in that direction. That might lead to a hard decision.
Thank You Sir,
Scott

 

[svan]

UPDATE,
First, I Hope Everyone Enjoyed The Birthday Of Our Great Nation Safely!.
So I Found The Oil Piston Seal That I needed on ebay. 11 bucks for 1 small packing!. Reinstalled the VRO Pump. Removed and Cleaned out All 4 Carbs.
dismantled them all the way down and used Gumout spray and Shop air to blow everything out. I did not see anything in any of the jets or in the Needle and Seat.
After a week away from home we used the Boat Sunday and Monday.
I did not add any fuel to the tank so I had 19 gallons of fuel that I put in a couple of weeks ago with Sta-bil 360. and approx. 4 gallons of fuel from last September that I had added Sta-bil 360 to.
I re-connected the Fuel/water separator and pumped the ball. I then dumped the Separator to see if there was any water in the tank. I did not "see" any water. So for those keeping score I am now running a new BRP Brand Ball and 10' of BRP Brand 3/8" fuel hose, through the separator and then direct to the fuel (vro) pump.
Ok, Engine starts right up, Idles Perfect, During a Slow Push to WOT it was Perfect. After I Hit 5200 rpm on plane trimmed, She ran Great, Just like it always had. Yes, 5200 is not redline, I may need a different Prop. So after running around, Playing with different Throttle settings I have found the "spot" where she struggles. Part Throttle, Before it's on plane, she "skips", Hesitates, then Bogs like she's running out of fuel. I tried to keep it at 3200 rpm which it seems to happen the most, I had to advance, and then pull back the throttle to maintain that rpm. anywhere from 2800 -3300 rpm is where it all happens.
I checked the spark plugs and all 4 were a little wet with fuel after this happening. They are new and have only 2 -3 hours on them.
I am soo Confused, Wide Open she ran Great! Any Ideas? Am I doing something wrong?
All of the OMC, Engines I have owned over the years, and I have never had this problem before.
Scott
PS,
I have used Non- Ethanol fuel 92 Octane for the last 4 years, But I know the Previous owner used to run 87 Ethanol fuel. If that Helps any.

 

[ct1762@gmail.com]

you will need to hook a dva meter up with a primary terminal extender to see what voltage is doing when the motor acts up. if it dumps then the motor skips, you have an issue with the pack or stator. I'd just cranking voltage test the pack, timer base and charge coil to make sure its all in spec. something might reveal itself. intermittent issues are not exactly the most fun thing to diagnose IMO.