# Homelite XL-12



## RKDOC (Jun 20, 2006)

Working on a XL-12 chainsaw. The customer thought he had carb issues so bought and installed a new carb, when it still would not run he brought it to me. The saw has 110 lbs compression. New spark plug with good spark. The saw will start on the first or second pull but will only idel for 10 seconds. I can keep it running a little longer by pumping the throttle trigger. I have adjusted the mixture screws both up and down. To high or to low it won't start. I am wondering about the reed valve? When the saw runs it spitts fuel out the exaust, but not the carb. Is there some way to tell if the reed valve is good without removing it? If removed what do I liik for?

Also when I look up parts on the Homelite web site they ask for a UT number. The serial plate is on the right side and say's MODEL XL-12 SERIAL 50591827. Where can I find the UT number?

Thanks for any help.


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## pyro_maniac69 (Aug 12, 2007)

if you just look up an XL-12 you will be ok

take the muffler off and see if the port is clogged, those old homelites lived plugging the exhaust port, check for scratched in the cylinder also

also, if the port is clogged, check your compression again after you clean it out and see what it says


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## RKDOC (Jun 20, 2006)

Thanks Pyro. I had checked the exhaust port and it was clear. There were no scratches on the piston or cylinder. However there is a wear mark about a 1/4 inch wide directly across from the exhaust port that runs the length of the cylinder. I cannot feel any ridge associated with the mark, justs looks like somthing has been rubbing.

Thanks for the help.


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## 30yearTech (Sep 14, 2006)

The mark in the cylinder is probably just where the ring end gap is. There is a locating pin on the piston to keep the ring from rotating and this will sometime cause a discoloration on the cylinder, but it's not a problem. If the reed valve was bad, chances are you could not get it to run other then when your pulling the starter rope. I would check for a bad crankcase seal. Is this saw new enough to have solid state ignition?


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## Lawnmowertech (Nov 12, 2008)

your ut # if none is present then you have a older xl 12 need to find out if it has pts or not also do you need any parts ?

the reed valve may have trash between it if my memory is correct its a 3 piece reed system 
i had a customer who had gas coming out oif carb reed was broke and scarred the throttle body handle so i had to replace the throttle handle and reed system then the saw ran correctly 


so do some checking


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## RKDOC (Jun 20, 2006)

There is no gas spitting out of the carb. I weill check and see if it has points or electronic ignition.

What should the point gap on a 2 stroke be?

Thanks


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## pyro_maniac69 (Aug 12, 2007)

same as a 4 stroke, .020


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## 30yearTech (Sep 14, 2006)

RKDOC said:


> There is no gas spitting out of the carb. I weill check and see if it has points or electronic ignition.
> 
> What should the point gap on a 2 stroke be?
> 
> Thanks


Many times the gap setting for the points is stamped into the point housing or cover, if not .015" on most chainsaws. Could have multiple or single reed valves, the newer ones had 4 reed plates I believe and the older "blue" ones had a single one.


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## Lawnmowertech (Nov 12, 2008)

if you need a parts list diagram of the saw let me know i can email it to you


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## RKDOC (Jun 20, 2006)

This saw has points. The points are correctly gapped (gap is stamped on housing) They do not look pitted or burnt. How can I tell if the coil is bad? any test? Is there any test for the reed valves? or do I need to disasemble and visualy look at them?

Thanks.


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## RKDOC (Jun 20, 2006)

Put the saw back together. Started on the first pull, ran a couple of minutes. Adjusted carb for best (not real good) idle. engine would rev up but not very far. Tried adjusting high mixture screw to best it would do. Eventuly the saw died. Now it will start on the first or second pull but will only run (not very good) for about 5 - 10 seconds, and won't rev up. Any other suggestions?

Thanks for all your help!!!!!!

P.S. I have installed a new spark plug. Has fresh fuel and new fuel filter.


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## Lawnmowertech (Nov 12, 2008)

RKDOC said:


> This saw has points. The points are correctly gapped (gap is stamped on housing) They do not look pitted or burnt. How can I tell if the coil is bad? any test? Is there any test for the reed valves? or do I need to disasemble and visualy look at them?
> 
> Thanks.


the coil is one of them hard to find coils but i have one also have the condensers as well as pts the reed valves are not the problem if gas is not pouring out by the carb now if fuel was spurting out of the carb while running then yes the reed valve would be partial opened 

i would varnish up the pts with some emory cloth reset them at .020 and see what happens then if it still acts up let us know those saws are built like tanks tough and tough again
on the fuel line is it tygon ? or the actual replacement line for that model saw ?


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## 30yearTech (Sep 14, 2006)

Since it starts and runs at all, then the reed valves should be alright. The condenser will not cause this type of problem either, in fact you don't even need a condenser for the ignition system to work. Even though the points are gaped properly they may not be making good contact, may need to be polished. 

Take a look at the fuel line inside the tank and the pickup too. Could have a soft fuel hose that's collapsing when the engine runs up.

Best of Luck...


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## RKDOC (Jun 20, 2006)

Can a coil going bad cause this problem? I replaced the fuel line and filter to no avail.

Thanks for all the help.


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## 30yearTech (Sep 14, 2006)

Try an in line spark tester, this should tell you if your loosing spark as the rpm's increase. I would be more inclined to think the points not getting a good connection would cause a spark loss then the coil, unless it does this only after the engine heats up, then a condenser breaking down or the coil could be the issue. If it does this from the start, I would doubt the coil, but I guess it's possible.


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## Lawnmowertech (Nov 12, 2008)

i agree with 30 year tech must troubleshoot the electrical system to find the problem with it 


its not carburetion or internal so its got to be electrical

check the wires everything for possible break in the wiring somewhere that may be grounded off against metal


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## RKDOC (Jun 20, 2006)

When I first start the saw after a couple of hours, it will start and run for a couple of minutes, then die. After that it will start on the first or second pull and run for 5-10 seconds. It never will rev up. When I checked the points, I ran my point file between the points a couple of times to clean tehm. I also checked the connections to make sure they were clean and tight. Pressure tested the crankcase and has a slight leak ( won't hold pressure, but leaks off slow) Customer doesn't want to replace seals.

Thanks for all the help.


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## Lawnmowertech (Nov 12, 2008)

RKDOC said:


> When I first start the saw after a couple of hours, it will start and run for a couple of minutes, then die. After that it will start on the first or second pull and run for 5-10 seconds. It never will rev up. When I checked the points, I ran my point file between the points a couple of times to clean tehm. I also checked the connections to make sure they were clean and tight. Pressure tested the crankcase and has a slight leak ( won't hold pressure, but leaks off slow) Customer doesn't want to replace seals.
> 
> Thanks for all the help.


i love them old saws 

is this one you working on blue or is it the red one ? the reason i say is i have about 25 blue ones out back


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## RKDOC (Jun 20, 2006)

This one is Red.


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