044 Walbro HD17 woes...any pointers (video)

[Martinm210]

So I spent the last few hours pulling and pulling, tearing the carb back apart, putting it back together and pulling some more.

I installed a genuine Walbro kit in the carb, but all I can get is a few puffs like there's a few dribbles of gas making their way in there that immediately get burned and it never really does much. This video gives you an indication of what I'm getting.

I started with the recommended 1 turn out with the limiter caps removed, and tried everything on the Low Speed screw from .5 turns to 2.5 turns and never could get much of anything more. I also tried the high speed at different settings and still about the same.

I did find that my sealing o-rings were bad on the adjustment screws, so I took the good ones off my 066 and put them on the 044 screws. That seemed to fix the rather not so snug feeling on the adjustment screws but the problem persists.

I also tore apart the gas tank vent down to nothing so it's ok. Checked the impulse line, it's ok. Checked spark and it's ok.

When I pull the carb apart the fuel pump area seems to be full of gas, so it seems as if the fuel pump portion is working.

The only thing I didn't do is test the pop off pressure.

Anyhow, I'm at a bit of a loss, not sure what else to try but maybe soak the whole carb apart in some gas or carb cleaner and let is soak overnight followed by some high pressure air.

So if it doesn't even want to start other than a little tiny puff here and there, could it be the pop off pressure is too high?

Any pointers on what to look for?

Do you think the larger 046BB would make that much of a problem with this carb? Should I be looking at an 046 HD16 or other carb for a better fitting replacement?

Thanks!
Martin

Video of my failure...
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[parrisw]

did ya pull the plug and look at it??? Is is soaked(flodded) or dry

 

[Martinm210]

did ya pull the plug and look at it??? Is is soaked(flodded) or dry

I did, even changed the plug. It did look a little wet, but not quite soaked. I checked the plug gap and it was right at .020", checked spark and I could see spark in the plug when grounded.

I also tried pouring a little gas right down the carb and it didn't seem to do much.

I was also thinking flooded so I did the usual wide open throttle pulls. My darn rope is a little short on this one (New one is in the mail), so I'm not able to make full pulls as I'd like. Maybe it is just a little flooded, it's just weird acting like it's only getting very small dribbles of fuel.

Squish on the cylinder was about .030"..it wasn't quite as tight as I wanted, but let it go.

 

[parrisw]

I did, even changed the plug. It did look a little wet, but not quite soaked. I checked the plug gap and it was right at .020", checked spark and I could see spark in the plug when grounded.

I also tried pouring a little gas right down the carb and it didn't seem to do much.

I was also thinking flooded so I did the usual wide open throttle pulls. My darn rope is a little short on this one (New one is in the mail), so I'm not able to make full pulls as I'd like. Maybe it is just a little flooded, it's just weird acting like it's only getting very small dribbles of fuel.

Squish on the cylinder was about .030"..it wasn't quite as tight as I wanted, but let it go.

It shouldn't be wet, likely will not fire if its wet. Any chance your timing is out??? Flywheel on correctly?

 

[rmh3481]

Hi Martin,
It sure doesnt sound like your getting any fuel but it may be flooding. Can you smell gas while pulling it over? Did you check the plug and if so was it wet? Did you replace or change the height of the metering lever when you installed the kit? Did you follow the instructions on where the diaphragm's go in relation to the gaskets? Was the ignition known to be good?

 

[Martinm210]

It shouldn't be wet, likely will not fire if its wet. Any chance your timing is out??? Flywheel on correctly?

OK, I pulled the second plug just now, it is a little bit wet, but if I wipe it down and try a spark test it seems to spark just fine. Maybe it's just really flooded in there.

I'll also check the flywheel tomorrow. I didn't see a way I could get the 044 on wrong, but maybe I just wasn't paying attention.

I did notice the very first couple of pulled I got kickback on, so maybe there is something to that. I figured it was just the extra oil I had from installing the cylinder giving it a little too much compression. The crank bearings were bad on the saw when I got it and there is some marking on the flywheel where the ignition was rubbing the flywheel, so I'm not sure if that has something to do with it too.

The plug is a Bosch WSR6F.

I've got the carb apart soaking in a small tube of carb cleaner right now I'll leave overnight and I'll pull the flywheel and do some more tinkering with it tomorrow. The one thing that bothers me is those little adjustment screw orings were pretty bad. I could potentially have some little bits of that rubber plugging up the low speed port. I can't see anything when I look down in there and I can seem to get some compress air down through backwards, but it's hard to tell with the idle jet being so small and not removable.

That gives me some ideas to try, I'll check them out...thanks!

 

[Martinm210]

Hi Martin,
It sure doesnt sound like your getting any fuel but it may be flooding. Can you smell gas while pulling it over? Did you check the plug and if so was it wet? Did you replace or change the height of the metering lever when you installed the kit? Did you follow the instructions on where the diaphragm's go in relation to the gaskets? Was the ignition known to be good?

I can smell gas and I can see gas vapors down in the throat when I stop pulling. The plug seems to be getting wet.

I did replace the metering lever and diaphram with the kit parts, but I did NOT check the lever height. The more you all mention it, the more I'm beginning to suspect flooding, perhaps just needs an adjustment of the lever down.

The kit didn't come with any instructions, but I followed the IPL regarding location of the diaphrams and gaskets.

On the metering diaphram I installed the gasket against the carb, and the diaphram on top. I even tried it the other way around thinking that was my problem, but it didn't seem to change anything. The bottom/fuel pump area was with the diaphram against the carb and gasket under that as shown here:

 

[parrisw]

Leave the plug out of the cylinder, so it'll dry out better. And make sure the gasket goes on first on the diaphragm side. Check your inlet needle adjustment too.

 

[Martinm210]

Leave the plug out of the cylinder, so it'll dry out better. And make sure the gasket goes on first on the diaphragm side. Check your inlet needle adjustment too.

Will do...thanks!

 

[parrisw]

I can smell gas and I can see gas vapors down in the throat when I stop pulling. The plug seems to be getting wet.

I did replace the metering lever and diaphram with the kit parts, but I did NOT check the lever height. The more you all mention it, the more I'm beginning to suspect flooding, perhaps just needs an adjustment of the lever down.

The kit didn't come with any instructions, but I followed the IPL regarding location of the diaphrams and gaskets.

On the metering diaphram I installed the gasket against the carb, and the diaphram on top. I even tried it the other way around thinking that was my problem, but it didn't seem to change anything. The bottom/fuel pump area was with the diaphram against the carb and gasket under that as shown here:

When you install the diaphragm, make sure to see how it connects to the inlet needle, some of them have a ring, so you have to hook part of it under the inlet needel lever, if you don't it'll hold the needle open all the time causing flooding.

The plug shouldn't be wet.

 

[Rookie1]

If it wouldnt even start with prime in throat of carb something sounds wrong. Maybe like Parris says its flooded. opcorn:

 

[bigbadbob]

You got a good arm!!!!

 

[blsnelling]

At least it's already broken in before it fires:greenchainsaw:

 

[chainsawboy1996]

You got a good arm!!!!

you should have seen me in december, iha my dads 044 out for a warm up with 36" bar might i say heavy as hell for someone my age 12.well my impulse line went bad (didn't know before hand) sat out in the snow for an hour :jawdrop: tryin to turn that beast up finally gave up after six inches fell

 

[Martinm210]

Found the culprit.

It's called worthless cheap crap overseas aftermarket parts:censored:

I didn't even touch the port or chamfers on the exhaust port, but it appears the top ring snagged on the exhaust port and fractured. I thought I noticed a drop in compression when I was first trying to start it, but thought it may have just been the oil in the cylinder burning.

Wish I could take credit for a strong arm, but I obviously had an unintended compression release which was causing the problem. Pulled the muffler and found several pieces of piston ring.

The exhaust port was fairly square, but it wasn't that bad. I'm blaming cheap rings on this one.

The worst part is not knowing if there's anything down in the case now....

The good news is, the cylinder is salvagable (even though I don't trust it now), and the best part is...I know what my problem is.

Live and learn, we take the risk when using aftermarket P&C kits, this is NOT "Stihl" quality.

I bought the kit from a guy on ebay, but these are all the same kits. Any 046BB kit could have this same exact outcome, I've already heard about it at least once before my turn. You get what you pay for....

 

[Lakeside53]

:taped:

 

[parrisw]

That really sucks man. I would buy from Baileys for that stuff, at least they'll stand behind it.

Will