Still stumped on 2001 90hp bogging down...

I have a 2001 90hp 60 degree with optical ignition

Here's how it all started... Was having a little problem with the motor shutting off occasionally while idling. Ran good w.ot.. The last time i did run it hard, the "hot" alarm went off due to a grain of sand in the pee hole. Imediately shut it off, and fixed that issue, and boat still ran fine the rest of the day. got home that evening and noticed that the carb bowls were leaking, due to them becoming warped. Next day, pulled them off and cleaned them good, went ahead and put a new kit in them since I had gone that far, and bought 4 new bowls. Put them back on, and boat cranked and idled fine. Took it out on the river, and did fine at idle. Gave it the throttle, and got up on plane good, but once i hit 5000 rpms it dropped off and wouldnt get over 4500 rpm. ran good at this point, just wouldnt get anymore rpms. took it home, talked to some people, and thought maybe i didnt adjust the floats right. Pulled the carbs off again, and readjusted the floats (with carb turned upside down, the free end just slightly higher than the pin end). Reinstalled them and ran it on the muffs, and it was idling fine. went ahead and ran some sea foam into the gas line directly, let it sit for 5 min and then cranked it back up, once the smoke cleared it ran good at idle. Went ahead and put a new fuel water seperator on it, and put new plugs in.Took it back to the river, and this time it would not get over 2000 rpms. Ran good but just started bogging down and dying if i tryed to get over 2000 rpms. I have since then checked the compression, which all cylinders were between 120 and 125 psi. I put an inductive timing light on all the plug wires, and seem to be getting a good consistent signal up to 4000 rpms (which i could occassionally get to briefly). Last season, i replaced the fuel pump and 2 years ago, I replaced the power pack and optical sensor. Any suggestions on where I should go from here?? I dont know what would be causing it to keep bogging down?? please help me before i go crazy and take a match to this thing... I will stay online for awhile to respond to any questions or advice.

Re: Still stumped on 2001 90hp...Please HELP me!!

Re: Still stumped on 2001 90hp...Please HELP me!!

Two things i did forget to mention. Before all this, a week prior< i did fix a bad fuel leak by the gas tank. the hose had a signifigant hole in it. Also, when I pulled the new plugs out, they appeared to be fowled out already after running it that little bit. Dont know if the sea foam did too much...

Re: Still stumped on 2001 90hp...Please HELP me!!

Re: Still stumped on 2001 90hp...Please HELP me!!

Ill chime in on the pee hole getting clogged, that would NOT be the source of any of your issues..it is just a tell tale....it isnt part of the cooling circulation!!!! once the water hits the pee hole it exits the motor...why would it be needed????

as for the other items....did the motor run good previously for you????

if it were me id look into fuel delivery and spark advance issues...

fuel pump, maybe is on culprit....

high speed jetting and or orifice in the carb...might be clogged...

did you run small wire through the tiny passages in the carbs when you had them apart???

compressed air???

bob

Re: Still stumped on 2001 90hp bogging down...

Boat was running ggod at w.o.t and a little ruff at times at idle. Just seems since the carbs came off is when i have been having this problem. I dont believe its the fuel pump. Its only a year old, and not the same as when it went out before. Seems to be delivering the fuel. Bulb stays firm. good pressure in the lines. To me, it seems that it just isnt burning the fuel when you give it the throttle. Mentioned spark advance. How do you test for this? I wanna think the optical sensor plays a part in that. When it went bad before, it was grounding to the flywheel, which i could visibly see, and it would make it have a miss.

I did run a wire thru the passages and use compressed air on it all.

Re: Still stumped on 2001 90hp bogging down...

Anymore suggestions??

Re: Still stumped on 2001 90hp bogging down...

Have you looked at the VST?

Re: Still stumped on 2001 90hp bogging down...

ok. Lost on that one. What is the VST?

Re: Still stumped on 2001 90hp bogging down...

shop2.evinrude.com..2001 90hp....fuel components....no.1 in the diagram

Re: Still stumped on 2001 90hp bogging down...

I take it, it is the vapor seperator. What exactly does it do, and how do you check it?

Re: Still stumped on 2001 90hp bogging down...

Can anybody help me with this?

Re: Still stumped on 2001 90hp bogging down...

well think about this question that doesnt seem to have been answered!!!!!

"""""high speed jetting and or orifice in the carb...might be clogged...

did you run small wire through the tiny passages in the carbs when you had them apart???

compressed air???"""""


just going through the motions isnt enough sometimes...detaillllllllllllll!!!

the carb is a finicky thing..or can be....

bob

Re: Still stumped on 2001 90hp bogging down...

I did answer that. Part of te high speed orifices are part of the bowls that were replaced with brand new ones and I did clean out, used a wire and compressed air on the rest of it. I had no restrictions and a good flow thru everything...

Re: Still stumped on 2001 90hp bogging down...

Vapour seperator has a float and needle it it.Check float and needle and make sure there are no air leaks around gasket.Also there is a small diaphram pump above it that runs off crank case pressure and sends the vapour to upper and lower bearings.Pull it apart and check diapram for stretching or holes.While its off there is a small hole with a little rubber o,ring where the vapour pump screws to.Cover that with tape and take the boat for a test run.If the pump is failing or your getting an air leak around the vapour separator the fuel system loses prime and could be the problem.I had similar probs with my 150 ocean pro.Losing fuel prime but the oms pump was still pumping oil and filling the carbs with oil,so it was bogging down and snuffing out.Took me awhile to work it out.Also my primer bulb never went flat the whole time i had the problems.Sounds to me you might have a air leak around vapour separator or failing vapour pump.

Re: Still stumped on 2001 90hp bogging down...

I havent got to the point of pulling the vapor seperator apart. Afraid once i break the gaskets apart, I should go ahead and replace them anyway and dont have the parts. I changed out the vapor seperator filter, o-ring, gasket, and nut (all brand new).It definately needed it! I did put some clear hose coming off the vapor seperator to the fuel rails just to see if i was not getting enough fuel. Everything looked good, never ran out of fuel to the carbs. lines stayed full the whole time. The only time anything changed was AFTERthe motor started to bogg down, some air bubbles got into the fuel line but never reached the carbs. Still at a loss... Just wondering now if it could still be the vapor seperator?? or start looking in a new direction before i tear it apart?!? any more suggetions?

Re: Still stumped on 2001 90hp bogging down...

Air bubbles???? I would still take vapour pump off and run it with your fiinger or tape over the little hole with the o,ring.That will eliminate vapour pump failure.

Re: Still stumped on 2001 90hp bogging down...

I will give it try in the morning and post my results. I do appreciate all the advice!

Re: Still stumped on 2001 90hp bogging down...

rebuilt the vapor pump today and put new gaskets and o-rings on the vapor seperator. Ran boat and still didnt have any improvements. Finally had a little help today where i could stay at the back of the motor to watch things. I still had the clear hose on the fuel lines so i could see what was going on with the fuel. started the boat and everything looked good. gave it some throttle and after 10-15 seconds, noticed that the fuel pressure was dropping. Squeezed the bulb and it was going soft (guess i never caught this because every time it started it back up before, it would be pretty firm after idling). When i squeezed it, you could see that it was dumping almost straight oil to the carbs, then after continuing to squeeze it, it would start mixing it again with more gas. Pulled one of the fuel lines off with the boat running, and it would squirt fine, then start to spit and sputter fuel, quit for a few seconds and so on over and over. I guess I'm back to almost the beginning with this thing and look at changing out the fuel pump. Sucks that it was just changed two seasons ago... If anybody has any other suggestions or input, I will end up going this route. Just hate to spend the $$$ if it might be something else.

Re: Still stumped on 2001 90hp bogging down...

It has oms pump connected and oil side connected.Run motor and put a screw driver on the oms pump when its running and count the clicks.It should click every 20 0r 30 seconds.If it is a fairly rapid click the fuel side is failing or an air leak in the fuel side.The clicking is the oil side of the oms pump working.If you have an air leak or diaphram problem on the fuel side the oms pump tricks its self and the oil side pumps more rapidly.

Re: Still stumped on 2001 90hp bogging down...

I will check it out. Im sure its going to be the problem. Just way too much oil being pumped in the mixture. seeing I have fouled two sets of plugs testing this thing would be a good indicator of that too... I have checked for air leaks up to the pump and havent found any.

Re: Still stumped on 2001 90hp bogging down...

I think so mate.I had the same trouble.Would run for awhile until the fuel,oil mix became straight oil and would smoke then snuff out.I checked everything.Had the oms pump apart that many times,checked for air leaks even put the oms pump on a 70hp johno and it worked.Like i said it ended up being the vapour pump.Check for 20 to 30 second clicks on the oms pump.If clicking frequently you know you have an air leak or fuel pump side of the pump problem.Just because you changed the diaphram in the vapour pump doesnt mean its still not the problem.I would still bypass it for a test.