98 Johnson Venom giving me fits and its my 1st boat.

[GSXRFANIM]

I will try not to make this too long...
So I find this Triton TR20 with the 200HP Venom at a dealership ran by an FLW Pro. He takes me out for a test drive in Nov and the boat hit 66 MPH on GPS with no problem. Its got a 24p Fury prop and he says it is setup great by our test run. He put me in the drivers seat and it ran great back to the ramp.
I decided to buy it and he winterized it for me since I wasnt going to use it up North in Ohio.
I take it out first time in spring and had a hard time starting it but got it running and ran it around our speed zone on our small lake. It seemed to run sluggish, maybe getting fogging stuff out. Eventually ran good to me.
The tank was below 1/4 and I put about 5 gals of fresh fuel and some fuel conditioner in on my next time out.
The engine has not ran good since that test run. The 2nd time out i noticed the water pressure gauge was pegged. I disconnected it and it was still pegged so I bought a new one. Also, there was still a steady stream of water coming from back of engine so I know it was getting pressure.
Now it wont get on plane. It starts great and idles decent but I can tell by the sound as it idles that it will not get up on plane. It doesnt sound crisp. Sure enough by the time I get to speed zone...No Plane. it just dredges along and will not get above 2200 rpms.
I talked to the FLW guy and he said to get it to a bigger lake to really run it.
I have taken it out a few times to where it will let me get up on plane but if I stop and fish for a little and try to go again...No Plane.
Its almost like the first try after putting it in the water, it will get up but if I stop and fish and try later...No Luck
I have changed plugs and the 1st time out it ran good but it still didnt get up to 65+ like my test run. We stopped and fished, then No plane.
The dealer has it now and he cannot find any problems but I know he said that he soaked the carbs.
I have done a lot of searching on this topic and it seems pretty broad with things to check.
The thing that I cannot find are the fixes that it took to correct some of the problems.
Anyone have the fixes that it took for similar problems?
This is a carbureted engine
It has the SLOW system that shuts down one bank of cylinders if it overheats. Anyone know how to test that setup?
What would the engine sound like if it was only running on 3 cylinders?

[Hair Jig]

I can't help with much else ... but your WP gauge is pegged because it had water in it and froze over the winter.

[JF1]

Good luck. I'm chasing a similar issue with my motor. First thing to do is a compression check. Did you change out with same plugs? I know these motors are temperamental and need to have identical plugs. Next time on water, while trying to get on pad, push the key. If it helps, then you have a fuel problem. Also, look at the sticky on top of the board for timing roller placement. Check that. Other than that, I'll defer to the big guns to help trouble shoot. Where did u take it to get worked on? We are pretty close to one another.

[javelin90]

If you run on 3cylinddrs it will run like crap. I would look at carbs being clogged up. The water gave froze from water in the line. I would do a breakdown test. Check and see if carbs need rebuilding? Did you add carbon guard and marine ethanol treatment over the winter. If nothing has been added prior to winter remove gas. Gas loosed octane over the winter so if you had 87 then you could possibly be at 85 or less. I replace plugs add fresh gaso
Ask seahorse or championman as they helped me a ton!

[SEAHORSE]

Yep, I second that it may be carbs because it is such a common problem with today's fuel and improper winterization, but it could also be a stuck shift interupter switch, sticky timer base, linkage problem, ignition problem, or fuel pump or fuel delivery malfunction.

In other words, have a trained tech check it over for you starting with a compression and an ignition output test, and a thorough visual inspection.

[GSXRFANIM]

I had it out on the lake twice this weekend to test. JF1, I have it at VIC's and if thats a picture of your boat, I parked right next to one that looks just like it.
It got up on plane but it took a lot of work and then it would only get up to 4500 RPM's and 55MPH. We took a plug out of the prop and it ran the same, ended up taking another one out.
He checked compression and spark, changed fuel filter and he said he put some stuff in the carbs to help clean them out.
I recently changed spark plugs with the exact ones stamped on the engine.
He was going to take it out for a test drive today.
What stinks is I am going down to Lake Cumberland this weekend and was really planning on taking the boat down there for the first time with the family.
I did try pushing in the key while running and it stopped the engine.
I also squeezed the primer bulb while trying to get up on plane and it did not affect the engine.
Also, recommended by the tech, I put about 6 gals of Premium(93 octane) gas in the tank to mix with what was in there already which is just over a 1/4 tank.
I am starting to think it could be a fuel problem whether its gummed up carbs, bad fuel or even pieces of fuel line in the system.
One guy told me that engines lose 25% of their horsepower during the hot months and they just dont run the same as they do in the spring or fall.
I guess we'll see. If I get it fixed, I will definitely let you all know.

[JF1]

That was my boat. They had it almost a month and victor couldn't figure it out. Mine is still doing same thing as before I took ot there. They are great pple and I typically don't have issues with them, but I'm taking it somewhere else now. Good luck man. Keep us posted

[GSXRFANIM]

Well Everyone, I finally made it to the lake with Vic to test run the boat and wouldnt you know. This whole time it was the prop.
The boat came with a Fury 26P prop and when I test drove it back in Nov the water temp was obviously cold and the air was 40 to 50.
It ran great. He made a few calls to probably another mechanic who said that prop is too much for that boat.
He put a 24P on and it got us out of the water like nothing.
Here is the good thing about Vics Sport Center. He didnt charge me a thing and wouldnt accept a gift card.
I told him that I would be pulling my kids around on a tube and he said I would do better with a 5 Blade.
So I followed him back to his shop and he swapped out the 24P with a stainless 5 blade.
JF1
He did say that he is not a big Evinrude Johnson guy but if you have a different prop, maybe throw that thing on there.
I would have sworn that I had bad gas or something. It just didnt sound good.
Not sure what prop you have on it but did you try taking a few plugs out of the prop?

[GSXRFANIM]

JF1, you also have to stay on them. I have talked to a very good source that told me that if you dont stay on them your boat could easily get pushed aside.
I dropped mine off on July 2nd. They went on a Ranger Convention the following week and didnt get to it until the 18th.
I started getting nervous because I am going to Kentucky this weekend so I told them that I really want to take it with me and they said Oh, Ok we will get her fixed.
Good Luck