cleaning carburetor on Shindaiwa 488

[DJ1]

Last Summer I decided to finally buy a good brand chainsaw and a Stihl dealer pointed me at a Shindaiwa 488 in the showroom. Did a little research and then bought it. Didn't start using it until December and January when some neighbors who had downed some big Pecan trees wanted someone to carry away the big pieces which I was glad to do. The 488 ran perfectly and I was impressed it started on the third pull when the weather was below freezing. It started and ran normally about two weeks ago when I had two truckloads of Red Oak to cut down to stove length. Yesterday I went to finish the cutting and the saw won't start. It's got about 25 hours of running time on it, maybe only 7 or 8 tanks of gas, since I bought it.

I've tested the spark plug and see a spark jumping. I've found the illustrated parts list at http://www.shindaiwa.com/usa/en/_docs/ipls/chainsaws/488.pdf

But the carb on my 488 looks a little different than the one pictured by the manufacturer's parts list. That picture has an air filter like a cylinder of foam or paper while the air filter on mine is only a fine mesh plastic screen.

I've sprayed off the sawdust on the outside of the carb. I've taken the top off of the walbro carb and found very fine sawdust in the little channels on either side of the pump gasket, part #3. I used carb spray cleaner to wash out the fine sawdust, put the gasket and top back on the carb. And it still won't start.

So can I get some advice on cleaning sawdust out of the carburetor ?

TIA for your time.

 

[mbopp]

The fine sawdust in the carb is "normal." Shin screen air filters do let a lot of fine dust in. If you look on the top cover you'll see two vent holes. That's where the sawdust is getting in the carb. The sawdust inside the top cover isn't coming from the fuel.

Are you looking at the optional air filter kit? That was a dual filter setup for high dust conditions but it's been discontinued. Not listed is a new flocked filter that replaces the stock screen filter. Kyle (upstanding guy and a site sponsor) at Edge & Engine can fix you up with one. I'm surprised he hasn't responded to this post.
IIRR Shindaiwa has either a one or two year warranty. Unless you've been inside a carb before I'd be tempted to let the dealer look at it first. Removing the carb requires a bit of finesse. And there are two carb models, the new ones have a single mixture screw instead of two screws on the pre-EPA models.

Will it fire if you dribble a little fuel mix (not gas or starting fluid) in the carb throat or spark plug hole?

 

[cjrenegade82]

If its that new I would take back to the dealer and let them clean and diagnose the problem. If its a decent dealer they wont give you any problems.
Then I would buy a different filter, many guys use the original filter and have no problems but to me they let more saw dust in than any filter should.

If you tear into it first and cant get it to run you may void the warranty.

 

[DJ1]

It's working now. Sunday night after cleaning the carb I drained the gas tank and put in about two ounces of carb cleaner, Chemtrol something, cranked it about twenty times to pull the cleaner up into the carb. Cranked it again several times Monday night and it wouldn't start. Tuesday evening it started on the second pull. Drained the carb cleaner and put in a half tank of gas and it starts and runs normally now.

Cjrenegade82. I talked to the dealer Monday morning and they told me the warranty does not cover 'not starting' !! But they'd be glad to look at it ! Their service dept charges $35 just to give an estimate. So that's why I try to fix it myself first.

Mbopp. Thanks for the info about the filters. I didn't think sawdust inside the carb could be normal. However I think there is more space than just the vent holes. I noticed that underneath the OnOff switch, the metal toggle, there is a gap of about 1/4 inch which allows sawdust and small shavings to get into the carb compartment. I'm going to try stuffing some foam into that crack and see if it makes a difference. To answer your question, it wasn't firing at all, the spark plug was sparking but it never fired.

Removing the carb out of the compartment is the part that worried me. Taking it apart is easy. Putting it back together again, in the right sequence, that's the challenge.

 

[Edge & Engine]

It's working now. Sunday night after cleaning the carb I drained the gas tank and put in about two ounces of carb cleaner, Chemtrol something, cranked it about twenty times to pull the cleaner up into the carb. Cranked it again several times Monday night and it wouldn't start. Tuesday evening it started on the second pull. Drained the carb cleaner and put in a half tank of gas and it starts and runs normally now.

Cjrenegade82. I talked to the dealer Monday morning and they told me the warranty does not cover 'not starting' !! But they'd be glad to look at it ! Their service dept charges $35 just to give an estimate. So that's why I try to fix it myself first.

Mbopp. Thanks for the info about the filters. I didn't think sawdust inside the carb could be normal. However I think there is more space than just the vent holes. I noticed that underneath the OnOff switch, the metal toggle, there is a gap of about 1/4 inch which allows sawdust and small shavings to get into the carb compartment. I'm going to try stuffing some foam into that crack and see if it makes a difference. To answer your question, it wasn't firing at all, the spark plug was sparking but it never fired.

Removing the carb out of the compartment is the part that worried me. Taking it apart is easy. Putting it back together again, in the right sequence, that's the challenge.

Quite frankly, that's BS. They should have checked it out under warranty. If it was determined that it was clearly something that you, the operator, did to make it "not start", that you would have had to pay the bill. If not, it should have been warrantied.
If it was dirt in the carburetor, it wouldn't be covered under warranty unless the air filter was defective.

There are several air filter options for that saw. One is the same style as the original filter, but part of it (the first stage filter) is paper flocked. The other option is the heavy duty Power Pro filter kit. Pricey, but it gives unrivaled filtration. That being said, the stock filter is adequate in most cases. From my experience, some fine dust in the intake adapter throat is normal and will not hurt the saw.

 

[DJ1]

I'm not sure what you mean by ''that's BS''. I quoted verbatim what the Land & Coates salesman said when I told them it won't start and asked about the warranty. It's just their policy. But it's also why I don't have much trust when stores talk about warranties. I expect they'd have opened and cleaned the carb, fix it in ten minutes, charge an hour of repair time and say the warranty doesn't cover it.

I can see both sides of the issue. Was it the owner being careless or a poorly designed air filter? There's no way I can prove I've been careful with my tools. If manufacturer won't pay for their time then the customer has to.

I've never cut wood without the cap and air filter in place so I say it's a weak design for the carb to choke on sawdust after 7 or 8 tanks of gas. Fine sawdust was packed into the little channels inside the carb around the rubber diaphragm. All I was doing was bucking red oak down to stove length but there were lots of knots and crotches. I still like the 488 but if this keeps happening then I'll have to upgrade the air filter or make opening the carb for cleaning part of frequent maintenance. Thank you for your time.

 

[Edge & Engine]

I'm not sure what you mean by ''that's BS''. I quoted verbatim what the Land & Coates salesman said when I told them it won't start and asked about the warranty. It's just their policy. But it's also why I don't have much trust when stores talk about warranties. I expect they'd have opened and cleaned the carb, fix it in ten minutes, charge an hour of repair time and say the warranty doesn't cover it.

I can see both sides of the issue. Was it the owner being careless or a poorly designed air filter? There's no way I can prove I've been careful with my tools. If manufacturer won't pay for their time then the customer has to.

I've never cut wood without the cap and air filter in place so I say it's a weak design for the carb to choke on sawdust after 7 or 8 tanks of gas. Fine sawdust was packed into the little channels inside the carb around the rubber diaphragm. All I was doing was bucking red oak down to stove length but there were lots of knots and crotches. I still like the 488 but if this keeps happening then I'll have to upgrade the air filter or make opening the carb for cleaning part of frequent maintenance. Thank you for your time.

What I meant is that the dealer should not have said that warranty doesn't cover not starting. At that point, they didn't know what was causing the problem, so they didn't know whether it was going to be warranty or not.
If it was an air filter problem, you would have noticed a lot of dirt/sawdust buildup in the air intake throat and carburetor barrel. Dirt buildup inside the carburetor (under the covers) is not much of an air filter problem. The air filter filters air going into the engine, not the carburetor. Fuel goes through the carburetor, and that is filtered by a felt filter inside the tank. I do not believe that the problem you described is related to the air filter. I didn't see it, so obviously I can't say for sure, but you will frequently find fine sawdust underneath the cover of the pump side, due to the atmospheric vent there (the little hole). This will not effect operation, that area is closed off by the diaphragm and there is no direct access to the actual carb fuel channels through there.
I'm more leaning toward the idea that there was some stale gas setting in the carburetor, maybe even varnished and creating a blockage.

 

[bowtechmadman]

Find a new dealer

 

[alderman]

Flocked filter

I put one of the flocked filters on a 488 and it definately makes an improvement in stopping the fine stuff from getting through. I can't understand why Shindaiwa doesn't make this a standard item.

I've also got the HD filter set up on a couple of my saws and while some say it ain't pretty, it does keep the dirt out.

 

[GrantC]

I've also got the HD filter set up on a couple of my saws and while some say it ain't pretty, it does keep the dirt out.

I think they're downright beautiful!

 

[cjrenegade82]

I also think they look great
Do they ever get in the way?

DJ1 your dealer is lazy and full of crap find a new one

 

[GrantC]

I also think they look great
Do they ever get in the way?e

Not any more than, say, a humpbacked Stihl like the 066 or 084. Personally, I don't even notice it.

-=[ Grant ]=-

 

[mowoodchopper]

Quite frankly, that's BS. They should have checked it out under warranty. If it was determined that it was clearly something that you, the operator, did to make it "not start", that you would have had to pay the bill. If not, it should have been warrantied.
If it was dirt in the carburetor, it wouldn't be covered under warranty unless the air filter was defective.

There are several air filter options for that saw. One is the same style as the original filter, but part of it (the first stage filter) is paper flocked. The other option is the heavy duty Power Pro filter kit. Pricey, but it gives unrivaled filtration. That being said, the stock filter is adequate in most cases. From my experience, some fine dust in the intake adapter throat is normal and will not hurt the saw.

:agree2: