2000 225 Fuel Starved @ high RPM

[thehermit]

Gang,
Motor: 2000 225 Johnson Ocean Runner Carbed

Engine had problem with check engine light. SO I removed the anti siphon valvle from my brand new tank. Engine runs fine

BUT

@ WOT the engine pulses like its running out of gas. SO tday we did a few more runs. It seems to act fuel starved @ about 4800 rpm. WOT is a complete pulse deal like its running out of gas. All fuel filters are new and visual inspection of clamps etc check out.

Bad or weakening VRO?????????????????????????

 

[jonesg]

Re: 2000 225 Fuel Starved @ high RPM

You need to troubleshoot it.
A timing light will show whether its dropping spark at speed.
Pumping the fuel bulb should show whether its starving (pump).
It'll probably be pump, dirt in carb or powerpack.

 

[tashasdaddy]

Re: 2000 225 Fuel Starved @ high RPM

is the fuel line primer bulb collasping, (going flat), if not does it help to pump the fuel bulb? if it picks up when you pump the fuel bulb. could be fuel pump, or air leak in fuel line.

if bulb is flat, the problem is from bulb back to fuel tank componets.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

Thanks guys.

The fule bulb does not go flat anymore. It did before I removed the anti-siphon. Now its fine. This is why I am focused on the VRO fuel pump. With my anti-siphon it was too weak to pull fuel from my tank @ any RPM but would idel all day long. Now with that anti-siphon removed and replaced with a brass nipple it no longer gets the check engine alarm and no longer runs the bulb empty.

BUT...now @ WOT and any RPM's above 4800....it seems to want more fuel.

I dont get the timing comment...other than the high speed ordeal it does great.

Also I may check the carbs a bit before spending the dough on a pump but again they run flawlessly at every other rpm.

Thanks
Hermit.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

I want to also add that on the oil pump side of the VRO....where there is a rubber like packing sealing the exterior....that is damaged. The motor was set in a truck bed on that and it seems to have maybee busted a seal. I dont know if that would effect the vacum in the VRO

Oh yea...plug looked oil fouled when compared to the manual

 

[tashasdaddy]

Re: 2000 225 Fuel Starved @ high RPM

possible.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

any way to check that with a vacum gauge?

 

[d.boat]

Re: 2000 225 Fuel Starved @ high RPM

any way to check that with a vacum gauge?

I think the service manual has pretty clear steps to test the fuel pump w/ vacuum gauge? I'm not sure about that never having actually done it, but I seem to recall from reading the fuel pump section of mine.

 

[23coastal]

Re: 2000 225 Fuel Starved @ high RPM

Had a similar problem with a 1995 J200. Motor would buck/hesitate several times a second at and above 3800 RPM. Problem was intermittent at first but was then almost constant. Rebuilt the carbs (good to do anyway). The fix was a new power pack. Need to troubleshoot, but can be difficult to do so at 4800 RPM.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

Well...local shop has the VRO...I will pull the carbs and clean 1st. I may also pull the vro and check the pulse limiter (after reading the book more).

What tests did you don on the power pack?

My prob is not intermitant. Its constant @ 4800 or better. And the removal of the anti-siphon made my check engine light go away. SO far all signs point to fuel/supply/presure.

 

[d.boat]

Re: 2000 225 Fuel Starved @ high RPM

Well...local shop has the VRO...I will pull the carbs and clean 1st. I may also pull the vro and check the pulse limiter (after reading the book more)...

fwiw, depending on the price they're quoting you locally, you can pretty easily save $100 buying that part online. Unfortunately Iboats doesn't seem to carry a VRO/OMS pump. The best price I found was Usavemarine, and they had fast affordable shipping.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

Thanks..I get 15% off as a commercial fisherman so I'll stick with my shop. FYI Usave is still chaper but I have the weekend to do it and its in stock here.

Reading the manual everything about surge points to fuel pump and carb clean. I have mentally commited to doing these things. I plan on keeping this motor for a while as it is new to me and in great shape otherwise.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

OK appears I dropped a cyl - port side middle cyl.

##???

While most all cyl are 125lbs...port side middle is @ 90. It used to be 130 a couple of days ago. Squirt a little oil in there and it goes to 100. Book says its outside allowable 80% The plug looked oil fouled. Book says thats excessive fuel and bad timing.

What will a low cyl cause the engine to do if I can fix the timing/fuel/mystery prob?

Would it run right with the variation?

Yikes...

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

OK its been a while but Im back with an update....and still have my super pesky little problem.

Fixed my cyl
120lbs comp on all 6
New VRO pump
Rebuilt carbs
replaced fule supply line...all new
services choke primer

The problem. After powering up the motor leans out the middle cyl on the port side (#?). AFter a short run a get surges and then check engine light. So I shut down and put home on the carbs idle circut which works like a champ.

After running at speed and when I get the horn you can pull the plug on my problem cyl and see light borwn lean condition. Run it on the idel circut after that and it looks just like all of the rest.

I only get to test on the water. That is the only way I cn create the symptom...so after 10+ ins and outs I am at my whitts end. When I ran in the yard I used some oil spray the check for leaks...nothing.

I have checked all of the T fittings and the fuel rail..they look good.


HELP??!!
Please

 

[jonesg]

Re: 2000 225 Fuel Starved @ high RPM

At this point I might try shooting some fuel into that lean cylinder when it acts up at speed on the water to see if it smooths out,

I watched a mechanic put 2 fingers in each carb throat to see if one reacted different, turned out to be my powerpack anyway but it was interesting to watch him trace it so quickly.

also a marine peak reading meter off ebay $62 to test the power pack.
http://cgi.ebay.com/ebaymotors/Mari...Z230353556405QQptZMotorsQ5fAutomotiveQ5fTools

 

[ezeke]

Re: 2000 225 Fuel Starved @ high RPM

Did you replace the head gaskets after the earlier compression issues?

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

Well....I replaced the head gasket...the cylinder/rings/rod bearings/wrist pin!! I had to hone the cyl that I cooked. I was lucky to "catch it in time" and it cleaned up easily. It had a stuck ring. This was likely casued by all the on the water tests and my lack of finding the root cause. I am proceeding very carefully now not to destroy my engine. Compression is back now strong.

I have a multi-meter. I'll give the power pack test a look in the manual.

I am also a little shy of high speed testing as that is when I am having my prob and at that point damage can happen quickly.

Is the "VACUM SWITCH" housed in something that can leak air????

 

[ezeke]

Re: 2000 225 Fuel Starved @ high RPM

The vacuum switch is next to the fuel pump and has a line connecting it to the fuel line. Too much vacuum caused by a restriction on the gasoline line triggers the switch and sets off the alarm.

 

[thehermit]

Re: 2000 225 Fuel Starved @ high RPM

So if I am getting the alarm (which I am) and after the alarm it needs a good ball pump (which it does) the air leak must be up stream of the VRO pump?

I have removed the antisiphon, run off a 6 gal tank, replaced in line filter,bypassed racor....all produce same result.

Readin the manual last noght about Power Pack failure and "multiple fire" at hig speed.....Could this case lean plug and alarm? Still have to test powerpack.

 

[jonesg]

Re: 2000 225 Fuel Starved @ high RPM

Unless you have a peak reading meter you'll need a DVA for your regular meter, about $25.