2.5 200hp, lean at idle?

[Greene]

I have wh-22 carbs. I just re-jetted the idle jets to .056" (from .046") based on recommendations I received here. Now at idle between 1000-1800, it runs a bit rough and coughs and sputters alot, especially when I come down from a run at plane speeds. Hole shot is great. It runs nicely below 1000 RPMs. Although it seems to take longer to warm up now or more exactly I have to keep giving it choke longer when I initially start the engine. I used to just hold the choke for 6-8 seconds, start it and it would be fine, but now I have to keep giving it some choke.

Do you think it's the new idle jets? It seems that plenty of people run even leaner idle's with wh-22.

Linc & sync problem?...

[wrechin2]

On wh carbs the idle circuit is air orfices. So it is backwards from what you are thinking.......To richen it up you should have went DOWN in size. You have leaned it out badly with the .056. To richen the idle mixture up you will need to go DOWN to a .044 or .042. The smaller the jet the less air it lets in thus it pulls more fuel out of the bowl 9similar to a choke system on a car). With the main jet it pulls fuel through it so the larger it is, the richer it is. Hope this helps!!!

[tlwjkw]

Everthing your sayin' is normal when ya lean out tha idle (46 ta 56) with exception of below. Hell, I've run as high as 70's in 22's and 20's and didn't have tha problem below. I did have ta change idle timin' a bit (ta slow down tha idle speed) with idle jets that big but made up tha difference with cam ta roller adjustments...............t




it runs a bit rough and coughs and sputters alot, especially when I come down from a run at plane speeds. ...

[Greene]

Thanks for replies.

I do realize that going from .046 to .056" jets, leans up the idle. The thought was that my .046" idle jets were too rich. My plugs always looked wet. And would foul easily just run idling around for a very very short amount of time. So based on some recommendations I went to .056". Like tlwjkw said people run much leaner idles than .056" on the 2.5L with wh-22's...although I'm sure my boat is bit heavier as it is a fishing boat..22' Mako center console.

Now the roller cam adjustments, what sort of adjustments should I check for?

Should I have those advancements kick in later....ie have the timing fully advanced before the throttle plates (butterfiles) in the carbs open at all? I know the butterfiles are fully closed at dead idle.

[wrechin2]

I have a modified 2.5 200 with stock idle jets (wh-46's) and it is doing just fine. The plugs will always be "wet". If you are fouling plugs you may look at your bleeder valves. I had one that was stopped up and would load up very quickly and would stumble and stuff out of the hole. Just a thought.
You want the idle to max before the plates really open. If not it will hesitate.

[Dave Strong]

Seems like you may be trying to fix another issue with jetting, 46-56 is a huge jump. As was stated before, check bleed lines, check valves, routing of the lines, all can give your problem. If your not a avid user of fuel stabilizer the carbs could need a overhaul, seen alot of "green" carbs this year due to ethanol. Whats the compression-leakdown like.
Dave

[Greene]

If you are fouling plugs you may look at your bleeder valves. I had one that was stopped up and would load up very quickly and would stumble and stuff out of the hole. Just a thought.


I checked the routing of the bleeder lines..all are correct. Other than checking the line routing is there anything else that could be wrong and if so how to check.



You want the idle to max before the plates really open. If not it will hesitate.
I check this today.

[Greene]

Seems like you may be trying to fix another issue with jetting, 46-56 is a huge jump.
Dave

I know, but from what I was told... .046" was very rich for wh-22 on a 2.5L 200hp, hence the huge jump. Like you seen posted some use .070+ idles



If your not a avid user of fuel stabilizer the carbs could need a overhaul, seen alot of "green" carbs this year due to ethanol.

I crap use oil, granted, but I try to be diligent with quickleen and the startron addivtive. However, before this problem really hit home I stopped using both for about a month, but i regularly fill and use the gas. Use approx. 20-30 gallons a week on a 50 gallon tank, all gas goes through an external Racor filter which is changed annually.


Whats the compression-leakdown like.


Compression is 110-115 across the board. Don't have access to a leak-down.

Thanks
andy

[tlwjkw]

You want the idle to max before the plates really open. If not it will hesitate.

Think hes sayin' tha same thing I was referin to 'bout tha cam ta roller adjustment. It will go ta more and/or full advance almost before tha throttle plates move.
With tha 70's I mentioned are not for a normal lake boat. That works on a "start in gear then put both feet on tha floor type boat"

As much gas as your runnin' through it don't think thats tha problem. Go back ta your regular method and see if it goes away. Without being there its hard ta say what it might be...............t

[Greene]

Think hes sayin' tha same thing I was referin to 'bout tha cam ta roller adjustment. It will go ta more and/or full advance almost before tha throttle plates move.


Gotcha!



Go back ta your regular method and see if it goes away. Without being there its hard ta say what it might be...............t

Regular = Better oil and quikleen regularly or
Regular = .046" idles, better oil and quikleen regularly.

[tlwjkw]

Regular = Better oil and quikleen regularly

:thumbsup:

[wrechin2]

Use a shot needle. it should suck out but not blow in. If it will not suck air out then it is stopped up allowing fuel to pool and flood. If it goes both ways, it is bad also. The very top and bottom (crank bearings) the bottomom on is either way and the top on is a in and not out. Hope this helps.

[Greene]

Use a shot needle. it should suck out but not blow in. If it will not suck air out then it is stopped up allowing fuel to pool and flood.

The bleed lines start and end... then shouldn't one end suck and one end blow? Closer to the crankcase should suck out right?




The very top and bottom (crank bearings) the bottomom on is either way and the top on is a in and not out. Hope this helps.

Could you please repeat?:confused:

[tlwjkw]

Suck on tha front (reed end). Clyinder end is bi :eek: Goes both ways........

[wrechin2]

On the top bearing cap, the check valve is flow in. On the lower bearing cap there is no check valve. On the reed side, it will suck air out and when you try to "push" air in, if working properly, with not allow air back in. 1 way check valves. Better???

[Greene]

On the top bearing cap, the check valve is flow in. On the lower bearing cap there is no check valve. On the reed side, it will suck air out and when you try to "push" air in, if working properly, with not allow air back in. 1 way check valves. Better???

So all valves are one way, right?

And if I understand there function properly, they keep fuel from puddling in the crankcase/combustion camber area by sucking from that area and pulling towards the reed side. So if I hooked up a syringe to the check valves, it should be able to suck from the crankcase area (but not push) and push on the reed side (but not pull).

[scc82]

other way around

[Greene]

So it pushes fuel from the reed valve area to the crankcase?

[wrechin2]

Fuel pools behind the reed. On the + pressure cycle it pushes the fuel from the front half (reed area) into the cylinders. Maybe you will understand better from the diagram.

[Greene]

So here's an update.

I checked the all bleeder check valves and they were fine. However, the throttle linkage was way out of whack. As soon as you gave the motor any throttle, the carb butterflies started opening. So I adjusted the roller arm on the carb linkage so that it was far enough away at idle so that the motor could advance the timing fully before the cam hit the roller arm.

Now the motor idles beautifully, no more lean sneezes. Since I had very rich idle jets before this problem with throttle/carb linkage setup probably didn't present itself because the jets were so rich. But now that the idles are more in line with what the motor should have, the premature opening of the butterflies was problematic, glad to have it fixed. I did have to adjust the WOT screw (not timing) so that the carbs would fully open. But the motor runs just great now, idles in gear at ~700 RPMs and maxed out at 5600 RPMs with a stiff 2-3 chop and 15 kts winds.

Just wanted to thank everyone here at S&F.

Andy

[wrechin2]

What jetting did you findly settle on??? I am tuning a set of 22's on a modified 200 and still rich at idle .048's (sounds like a 4 stroke) and gotton it close with .086 mains. Plug with a 2-3 minute run and a wot chop are a darker brown with a little dampness on the piston and pulling a couple more rpms on top. With .082's they were tan.

Rans a set of 46's on another modified 2.5 and idle jets were good. Go figure......

Did I send you a manual on this engine?????

[Greene]

wrechin2-

Q1.) I running .056" idles, no vents, and .08-.084" mains. A throttle chop at 4500Rpms and the plugs look paper bag brown to darker brown.

Q2.) No you didn't sent a manual. I will gladly accept however :smiletest:

[wrechin2]

PM me your email address. I will send you a factory manual that covers 92-00 2.0L and 2.5L.

Glad to see we are pretty close on the mains. Mine is a heavy modified engine. Doing real well. Just a little sluggish out of the hole then comes alive.

[Greene]

With .056" idle, my engine takes off like lion attacking a wildebeest

[wrechin2]

Check you email....