Pushing fuel out exhaust

[jayb]

Working on a super ez. Saw starts revs up but will not idle. Spark plug wet, pushes a little fuel out exhaust and around cylinder release valve. also blows a little fuel back out the carb into the air box. I rebuilt the carb with a OEM walbro kit with check valve, made no change. pressure tested fine. did find the throttle stop was bent on the carb and not even contacting the idle screw. Reeds look good. When i removed the handle/airbox the top of the cylinder gasket did fall apart so I know thats an issue. Any thoughts?

[edju1958]

That gasket is important.You can make one out of 1/64 in.Karopak gasket material.I've done it,it takes a little time.The other thing is your metering lever may be set a tad too high which may be causing your saw's flooding issues.Those HDC carbs are touchy little devils.

[jayb]

I will get back in that carb and check that metering lever. Since I will be replacing the cylinder gasket I will be pulling the cylinder anyway. Is it worth it to slip in a new piston and rings? From what I have read on here there seems to be a debate on honing or not. Money is not an issue, just doing this as a hobby in the winter months. This is my first time getting this far into a saw.

         

[edju1958]

The piston looks great with no scoring.I'm assuming the cylinder is good too.Try taking a compression test if you can.Chances are the rings are good too.These saws will run very well down to 135 psi.I believe when they were new they were running at 175-180 psi.,hence the decompression valve.

[blythkd]

Basically most of the things to look for on the fuel running through it issue are:

1. Like Ed said, the needle lever adjustmnet. This is one of the most common things to check for. Should be level with the bottom of the carb body. I've set them a few thousandths lower in a pinch, kind of a custom adjustment if nothing else works.

2. Bad inlet needle. If it has a noticeable ring around the tip, replace it.

3. Could be varnish on the tip of the inlet needle. Carb cleaner will take care of that.

4. Long shot but could also be the spring. Most of these carbs, different brands and styles, use a very similar spring that look like many of them could be interchanged between carbs. But the truth is, there are slightly different lengths and tensions that make a difference. Someone could have put the wrong spring in it at some point.

[jayb]

Well the metering lever was a bit high in the carb and I cut out a gasket to go between the air box and crankcase without pulling the cylinder. slapped it all back together and runs slightly better. I didn't run it long enough to really adjust the carb cause I noticed the gasket between the carb and intake is leaking fuel. Also noticed there is quite a bit of slop in the needle bearing on the bottom of the connecting rod. I guess it's due for a serious overhaul.

[xl130]

I definitely see some deep scratches on the piston. There looks to be a bit of damage to the rings as well. Probably not what’s causing you to flood though.

Have you checked the compression? Those little saws have noticeably good compression when you pull the recoil.

I would suggest a new piston and rings, clean the transfer off the cylinder walls and new seals It’s a big job but well worth it if you take your time.

If you’re still getting good compression and you don’t care to sell it ever then I suppose you could just run it.

If you plan to keep it in service for another 40 years then total overhaul is the way to go.

[jayb]

Feb 27, 2023 20:49:02 GMT -5 xl130 said:

If you plan to keep it in service for another 40 years then total overhaul is the way to go.

Yes, the exterior of the saw is in quite nice shape, I plan to do a complete overhaul. I have started ordering parts.