What's on your bench today?

[spudulike]

Well using the new tool today after fitting new seals to this 200t. The gauge is staying put and when the rank is turned it moves up and then down by 2 inhg. But stays still after movement. So looks good on vac. Just need to pressure test with my old made up one.

 

looks like you are using a red permanent marker stuffed in the carb boot as well:lol:

[Rich2484]

Yes I am.

 

Although this saw is getting to me now. Half a day on it already. It passed both vac and pressure tests. The comp is not as high as I would want but is on 150psi. It will run on half throttle but won't tickover and is a pig to start. I've changed the carb but no change. I'm looking at the tank vent at the mo. but fuel is getting in ok.

[mikerecike]

Yes I am.

 

Although this saw is getting to me now. Half a day on it already. It passed both vac and pressure tests. The comp is not as high as I would want but is on 150psi. It will run on half throttle but won't tickover and is a pig to start. I've changed the carb but no change. I'm looking at the tank vent at the mo. but fuel is getting in ok.

 

 

new plug? plug gap? flywheel gap?

[Rich2484]

Flywheel gap is done from strip down. Spark is really good outside the engine and plug is clean. Going to swap it for a new one just to be sure but not that. The impulse line is good. Removed the old tank vent completely to remove this issue.

 

I'm not getting the usual squirt of fuel from the fuel pipe when I remove it from carb with the vent in....

 

The saw will rev up but the moment it goes to tickover it will idle fast for a short while with the tickover screw all the way in then die out and won't restart unless it on half choke.

 

Eating lunch while I think about it then having another rcrack at it.

 

I do have a husky saw waiting to be checked out so if I get annoyed with the stihl I will jump on the husky.

[spudulike]

Yes I am.

 

Although this saw is getting to me now. Half a day on it already. It passed both vac and pressure tests. The comp is not as high as I would want but is on 150psi. It will run on half throttle but won't tickover and is a pig to start. I've changed the carb but no change. I'm looking at the tank vent at the mo. but fuel is getting in ok.

 

You sure the new carb is a good one? Make sure the impulse line is clear of blockage....AND connected, make sure the carb boot is alligned correctly and the impulse hole in the carb lines up with it.

 

The symptoms you have are classic for a bad carb:confused1:

 

As Mike said - check the ignition over - you may have the kill wire earthing or too large a coil to flywheel gap - this will make it run pretty bad as the ignition will be retarded!

[Rich2484]

The carb is a new 020 one from the box. It works fine as I have used it on other saws to determine the carb issue before. An dits works on other saws.

 

Will look into the impulse lines in a bit. I'm hungry

[Rich2484]

Right. Tried a total of three carbs now and the same thing each time. Re done a vac and pressure test and the crank case, impulse and boot are all leak free in either test. Spark is very good and gap is good.

 

Comp tested again and that is at 160psi.

 

The one thing that is really stuck in my head over it is the fuel tank. After trying to run and taking the fuel pipe off the carb there is no pressure in it. So o fuel squirts out of the pipe. Not sure how this would effect it much other than not enough fuel is getting into the engine. The plug Does look a bit dry when removed but the saw will go to full revs no problem then hold a high tickover before dying out. I've looked at the meter valve and it looks ok but again does the same thing on two other carbs....

[spudulike]

Strange one Rich, check the tank vent is free - not sure if you have the red rubber mushroom or the one on the tube but make sure it allows air in and seals when blown.

 

Check the fuel line is OK - you can pressure test the line with the filter off and then use your new vac gauge on the fuel line to check the tank vent is OK.

 

I guess the impulse line has been connected correctly on the underside of the handle?

 

When you pressure check, waggle the impulse line about a bit where it goes in to the engine - they often get damaged here.

 

When you are pressure/vac testing have you rotated the crank round with zero loss of pressure - you need to note what it is with the crenk in a certain position and then rotate it through 360deg but give it small back and forth "waggles" as it goes round - if it leaks at all then push on the crankshaft on the clutch side and see if air pisses out in certain positions so find out where in its rotation it leaks and apply pressure in this position - these seals go hard and lose flexibillity.

 

Other than that, make sure the carb boot tab is located slightly to the right of the corresponding mark on the cylinder - it ensures the impulse hole lines up correctly!

 

Good luck

[Rich2484]

Yep yep and yep. Checked all. The seals are new (the same ones you reccomeneded) and there is definatly no leaking when I rotate the crank or wiggle it about, well try to anyway, since the new bearings and seals went in there was no movement at all in the crank, but with the worn ones the crank would move left and right a bit.

 

Changed the fuel line and it is no squirting fuel when I pull it off and the tank vent is working fine, its the vent in the tank not the y shape pipe.

 

Will not tickover. Have to go to choke then half choke to get it to run, the tickover redrew is all the way in but the saw is not over revving on tickover, it will run for a short time then die out and to restart have to go back to choke and a half choke but still die out on tickover.

 

I think I'm actually beaten for once and I think this saw will make its way back to customer. NOT what I want to do but I just can't figure it out.

[SpannerRat]

Could it be an air leak above where you block the boot when you vac and pressure test, perhaps between boot and carb?

 

 

Sent using Arbtalk Mobile App