90HP V-4 flooding out

[workinoffsho]

I have a 81 mod 90 hp Johnson V-4 I recently too it into the shop for a tune up. The problem I am having and the mechanics are not able to figure out is this. The motor will start and run at idle both in the water as well as with the ears. After launching the boat and letting it warm up a few minutes I back off of the dock and when I give it the throttle to take off it floods out. I have to restart and lift the fast idle where it will only run around 3000 rpm then after a few seconds it will rev to 5000 rpm. I then will try to throttle up and again it will flood out. I will have to repeat the procedure three times before it decides it wants to go. I noticed this after the second time taking the boat out after the tune up. It will do the same thing after I have anchored for a while and have to idle out of a shallow area. It all points to some type of flooding to me but I can't figure out how to correct the problem. Any help you can give will be greatly appreciated.

 

[DJ]

Re: 90HP V-4 flooding out

Have the carburetors been rebuilt? New floats? Float levels-OK?

 

[ob]

Re: 90HP V-4 flooding out

since mechanics are stumped and we don't yet know why it stops lets just say it stalls when throttling up . next time when throttling up before it falls try rapidly bumping primer button to see if it grabs . could very well be you have a fuel starved condition.this can be corrected assuming your carbs are fine and have no obstructions in low speed jets by opening mix screws on each carb in 1/2 turn increments and see if it settles out . If mechanic performed tune -up on engine I would hope he either performed it by water test or with dynomometer on prop shaft.

 

[workinoffsho]

Re: 90HP V-4 flooding out

djohns19 No the carbs were not rebuilt. Having read through the manual I seem to be leaning in the same directions of the floats possibly sticking also but I figured knowledge from many fellow boatersis usually better than one dumb a** mechanic.

 

[workinoffsho]

Re: 90HP V-4 flooding out

OB Yes I have tried the bulb with the aid of my brother. His Mariner had the starvation problem and we had to remove the inline filter on the fuel line. Short story my motor was on a 19' Welcraft prior to tune up then it was installed on a new custom aluminum 15' hull. I went with larger fuel line and a large bore inline filter. I didn't have the first hint of trouble with the motor prior to the fine workmanship of the mechanic. I am offshore at the moment but when I get in I will pull the carbs and check the floats then thy the adjustments you mentioned Thanks

 

[ob]

Re: 90HP V-4 flooding out

I was speaking of the primer button on your controls not the squeeze bulb .the control primer button will allow fuel to bypass carb and discharge into intake port

 

[workinoffsho]

Re: 90HP V-4 flooding out

OB I tried that also all it did was die. I guess when you mentioned starvation of fuel I locked onto my brothers problem. One thing now that you mention it when I would try to restart after it would die out if I would push the primer it would flood and the engine would only rev to 3000 rpm and it would take up to 30 seconds with the lever all the way up before the rpm's would increase. One thing I will check also that just hit me is my air intake. In south La. we have these darn dirt dobbers that tend to build dirt nest everywhere. Starving for air might be another avenue also because it's getting the fuel causing the flooding problem but no air. ANy ideas will help Thanks a bunch

 

[ob]

Re: 90HP V-4 flooding out

Also, check carb fuel jets . removable with small diam screw driver as these little buggers get obstructed with varnished fuel and related goo quite easy.As mentioned by another post on this thread it is highly recommended to do carb service .floats and needle valves.float adjustment.also look for any obstructions in air jets located upper side of carb assy.

 

[Reel Appeal]

Re: 90HP V-4 flooding out

I agree with ob,<br /> Clean out those carbs....Check especially for dirt/debris between needle valves and seats.

 

[workinoffsho]

Re: 90HP V-4 flooding out

I have ordered carb kits along with stock jets and all gaskets needed to tear into the carbs when I get home. I was planning on it anyway but when I found this forum I decided to see what others had to say. I work overseas on a 28 day schedule and when I am home the boat does get use. What do you feel are the pros and cons of running the fuel out before storage of any length?

 

[ob]

Re: 90HP V-4 flooding out

Depending on down time I have pretty good result using a product called STA-BIL mixed in fuel .inhibits varnishing and aids in stabilization of fuel.

 

[workinoffsho]

Re: 90HP V-4 flooding out

I use that in my 24' Cobia I/O because it its for 9 months and gets used for 3. I didn't know how it would act with the fuel/oil mix. It is very seldem that the boat dosen't get used less that 4 times when I am in.

 

[BassMan283]

Re: 90HP V-4 flooding out

Sta-Bil works fine with fuel/oil mix.

 

[workinoffsho]

Re: 90HP V-4 flooding out

Hey Guys good news I'm back in business. Being I offshore I called my Father-in-law which is a very good jack of all trades to see if he could clean and re-build the carbs. He got the kits I ordered from my house and dove into the task. He said after three hours a little sweat and a few choice words from those brass jet screws he arose the winner. Now for the test he took the boat to the local launch and took it for a test. He adjusted the carbs a couple time and then it was working perfectly. He said from a dead stop he would gunn it and it would run like a scalded monkey without any hesitation whatsoever. He took it home and ran it again the next day trying his best to duplicate what I was doing but it didn't kill or studder. He said from the looks of it the primary jets had gummed up quite a bit and possibly catching trash until the high idle would flush it out. This in turn would allow the fuel needed for the primary. OB it looks like it was starvation was the thing due to clogged primary jets. To all you guys who helped out my thanks goes to you and a 12-pack to my father-in-law. I'm glad i found this great fourm the quality of the people and advice is the best I have seen. MAny thanks again