395xp: Ran Great! Now it don't.

[Jed]

O.k. Burnham emboldened me to consult the gurus before I get myself in over my head.

I bought--and paid far more than I was wise to give--a used 395 with a new big-bore kit in it about five months ago. I use it about once a week in place of my 440, and I was just starting to really like it when it "broke down" yesterday.

Here's what happened: It got nice and warmed-up after pulling through big wood for about half an hour when I ran it out of gas. I filled it up. I choked it and it burped. I flipped the blue switch in to run and it ran: for about five seconds, then died. Pull like mad on the chord on "run" with the throttle open: nothing. Put it back on choke: burps immediately. Push blue thing in to "run": starts and runs immediately--for six seconds then dies. Repeat ad nauseum.

An old-timer back at the shop said, "Yeah, try just cracking the gas-cap open again, and see what that does: sometimes the little vents get messed up, then check the fuel filter... etc. etc."

Am I up against carb trouble? Have any of you Orange Saw guys ever dealt with this before.

 

[woodworkingboy]

Jed, it sounds like it could be a number of things. Not getting sufficient fuel seems a likelihood. Start troubleshooting procedures by perhaps first checking hoses. Make sure the carb bolts are tightened down sufficiently.

 

[Jed]

Will do Jay. Thanks.

 

[SkwerI]

Vapor lock, the fuel was boiling in the fuel line so you weren't getting enough fuel to the carb. That's why it still burped when you choked it. When it happens again, choke it a little more to get it running and then run it for a minute or two without a load to cool the motor down. A running saw will cool down much faster than shutting it down and letting it cook in its own heat. Or your other option is to set it down in the shade and take a 10-15 minute break.

 

[Al Smith]

You have some type of fuel delivery problem and most likely the carb .I kid you not I've had saws that ran fine for years then all the sudden acted up for no reason .90 percent of the time it was something in the carb and usually just stiff innards .

Try as you might you can't predict when the damned things are going south .It might be an older carb or one that sat for a while then runs great for a week or so and dies on the vine .

Like I said in the thread B had on the 064 ,that little Poulan ran flawless for over 35 years then all the sudden just took a crap .The 038 Mag I got from Tom would only go about a year between rebuilds of the carb .There's no ryme nor reason to it .

 

[Jed]

Brian: Thank you very much. I really appreciate the suggestion, but this problem might be a hair beyond that. I grabbed the saw fresh out of the saw-shed today (pretty cold all night) and it did the exact same thing. It won't stay running.

Al: Thank you (also) very much. I gotta feelin' you're right.

 

[Al Smith]

Oh for crying out loud a carb rebuild is a piece of cake .It isn't like splitting the cases or something .Even the most expensive kits are less than 25 and I'd imagine if Baileys carries them about 15 or less .Take you about 45 minutes if you've never done one ,15-20 if you have .

 

[SkwerI]

Yup, if it's doing that cold then the high end jet is plugged. Carb rebuild time.

 

[Al Smith]

Kits though Baileys ,$9.99 .Search under Tillotson HS .

 

[Jed]

Can't thank you enough boys...

Time to have a go at it.

 

[SimplyArbor]

Exact same thing happened to my woods ported 359. New plug, fuel filter, and carb kit did the trick!

 

[Magnus]

Did you look at the plug? Changed it to a new correct and tested one?

It sure sound as a fuel delivery problem.

When filling up a saw you loose the pressure in the tank. Tilting it from side to side 2-3 times saves a lot of pulls. I wiggle them on the bench after i worked or fueled them a bit.
It will create a pressure in the tank that help the pump.
If there is no pressure and membrane or valve is a bit stiff it will not run right.
As saw run it will be a combination of posetive and negative pressure in the tank as fuel go out, air in and movements.

 

[woodworkingboy]

Jed, if you haven't done it before, the metering diaphragm that's the one under the four screws. If it is getting stiff or possibly torn, it is time to at least replace it or better yet, replace it and the pump diaphragm, the one on the other side. Some of the kits come with a new needle that goes beneath the metering diaphragm and the lever as well, the complete rebuild kit I think it is called. Easy to replace all those things, but just note the order of diaphragms and gaskets when you re-assemble. If you put in a new lever, check the height. Easy peasy.

Wiggling is a cool trick, Magnus, I'm glad you mentioned that before.

 

[Al Smith]

On this subject of carb rebuilds depending on the model of carb there are several levels of rebuild kits available .For example on a Tillotson model HL which is a larger carb there are three that I know of .The basic kit which is just the diaphragms and gaskets is about 5 bucks .Next level up has the more robust backers made of a mylar type material for about 8 .The complete set with the fuel lever,welch plugs and all the goodies is about 20 .

FWIW the only reason I make reference to Baileys for parts is I know the company is more familiar to people .I could list a hundred places but so can Google .

 

[Burnham]

Let us know how it goes, Jed.

 

[Cut4fun]

Just in case anyone is interested. My local dealer has new 395xp with 24" for $900 + tax now.