Stihl Magnum 038 difficult to pull starter cord

[JackD]

I have a Magnum 038 chain saw that the pull start feels like it has to much compression or no outlet. I have removed the spark plug and it turns over easily. I checked the muffler by taking it off and it is clean and in like new condition. I could see the piston and what could be seen looks good. Any thoughts or suggestions?

 

[Wood Doctor]

I have an 066 Mag that seems to do the same thing. The saw runs fabulous when I get it started, but it seems way to hard to pull, even with the decompression valve down, choked or not choked. I'll be interested to see what others have to say about this.

 

[JackD]

I have an 066 Mag that seems to do the same thing. The saw runs fabulous when I get it started, but it seems way to hard to pull, even with the decompression valve down, choked or not choked. I'll be interested to see what others have to say about this.

I cannot start mine, I don't get it to turn over enough it feels like the piston might be making one cycle,

 

[drf255]

I had an 066 w a bad bearing. Piston would intermittently hit Squishband.

Also, make sure you got the right length plug in there.

If you put too long a plug, it could be acting as a stop. Look through the plug hole at the piston crown with a flashlight. See if there's a shiny spot, anywhere.

 

[Rx7man]

can you turn it over at all, and it's just difficult? or does it not turn over with the plug installed.

I'd try a compression check first.

Also, it makes a HUGE difference to have a full spool of rope on the recoil (better leverage).. take the starter cover off and make sure it's right filled up... the 2100's I have were a BEAST to crank over with 180 PSI when I didn't have a full roll on the starter, when I replaced the rope they felt like a 60cc saw in comparison! (one of them had only about 20" of rope left, giving you about a 2" diameter spool instead of the 3.25" or so it should have)

 

[albert]

Check the starter pulley for a split/crack.

 

[JackD]

I had an 066 w a bad bearing. Piston would intermittently hit Squishband.

Also, make sure you got the right length plug in there.

If you put too long a plug, it could be acting as a stop. Look through the plug hole at the piston crown with a flashlight. See if there's a shiny spot, anywhere.

Actually the plug is the original, will check for the bearing, thanks.

 

[JackD]

can you turn it over at all, and it's just difficult? or does it not turn over with the plug installed.

I'd try a compression check first.

Also, it makes a HUGE difference to have a full spool of rope on the recoil (better leverage).. take the starter cover off and make sure it's right filled up... the 2100's I have were a BEAST to crank over with 180 PSI when I didn't have a full roll on the starter, when I replaced the rope they felt like a 60cc saw in comparison! (one of them had only about 20" of rope left, giving you about a 2" diameter spool instead of the 3.25" or so it should have)

It doesn't really turn over with the plug in. I did check the pull rope and it appears to be all there.
Haven't done a compression test yet. looks like I am going to have to bring in to a shop, Cha Ching/Cha Ching

 

[Wood Doctor]

It appears JackD and I have two different problems. My 066 Mag starts really hard but runs fine. It just about jerks your arm off to start it. Compression seems huge, and cutting power is also huge. I installed a BBK at the request of the owner.

Maybe it just needs a good jockey to run it, some guy that used to whip wild stallions near the finish line.

 

[alexcagle]

Make sure the deco plug is In fact actually working on your 066 mag, (wood doctor). They have a tiny hole that can easily get plugged up with carbon and goo.
On an 038 mag without a deco; I'd try a different coil. I think some modern "all In one" coils have a circuit that retards the timing at lower rpm, and have full advance at higher rpm. Also if you don't have an elastostart, I'd put one back on it.

 

[TreeswingerPerth]

Same thing happened to my 038 Mag , after much stripping and checking I discovered the key on the flywheel had sheared and the wheel had moved slightly .
It would start eventually but was hard to pull , but once running didn't seem too bad .

 

[Conquistador3]

Even, if you already had a look, double check the exhaust port after removing the muffler.
I had an MS290 which was incredibly hard to pull-start but once started run fine. It seemed like the thing had twice the compression it should have had.
A second and closer inspection revealed some (not much really) carbon buildup on the port. Removed that and now the saw starts as it should.

 

[uglydukwling]

My 038 has been hard to start since new, but at least it was consistent (a few pulls with the choke on, it would cough, choke off, a couple more pulls and it would start and run). It finally got so it wouldn't start at all. One of my friends had the same saw with the same problem and he said he put a new carb on his and it made it into a new saw. So I tried that, but it didn't help.

It turns over easily, with about the same effort as always.
I haven't measured the compression but it seems pretty good judging by the thumb-over-the-spark-plug-hole test.
The new carb is set up according to the manual. Is there a better setting?
If I give it a whiff of ether (I'm sure that can't be good for it, but I'm beginning to think I don't have anything to lose) it starts and seems to run as well as it ever did.

What do I try next?

 

[alexcagle]

ember: 139918"]I have a Magnum 038 chain saw that the pull start feels like it has to much compression or no outlet. I have removed the spark plug and it turns over easily. I checked the muffler by taking it off and it is clean and in like new condition. I could see the piston and what could be seen looks good. Any thoughts or suggestions?[/QUOTE]
Check and see if the crankcase isn't full of fuel and causing a hydraulic lock on the downward stroke. Take the plug out and air filter off. Then with the piston at Its top dead center, point the the muffler straight up and pull the trigger to let any gas that might have pooled in the crankcase run out the carb. It's rare, but I have seen it.

 

[HarleyT]

Drain out all of the fuel, take out the plug and pull over the engine a lot, let it air dry out for a day or so.
Then put the plug back in, and then try to pull without adding fuel, see if it pulls easier.
If it does, go through the carb, and replace the needle, replace the diaphrams if they are stiff.

If it doesn't pull any easier, there may be too much carbon in the combustion chamber{top of piston, etc.}

 

[alexcagle]

I agree Harley T.
-and hold the throttle wide open it like like an old flooded Ford; till it fires up.

 

[Wood Doctor]

HarleyT said, "...Too much carbon in the combustion chamber (top of piton, etc.)..."
-------------------------------
Just out of curiosity, isn't this generally caused by running too rich at WOT? (i.e., hi-speed setscrew too far open, 4-stroking, etc.) If not, something else?