Got another stubborn one.. Stihl 017

[a. palmer jr.]

I have a Stihl 017 I've been working on for a friend, trying to get it going. I put fresh fuel in it, checked spark and it's okay, new spark plug anyway, compression tested at 130 so it should be okay. Squirted a small amount of fuel in spark plug hole, put it back together and it wouldn't hit a lick. Tried another spark plug and still wouldn't hit. I would think the thing should hit at least once with fuel in the chamber, spark, and compression. I'm not sure if I checked it for the muffler being clogged but I'll try that tomorrow. What do you think?

 

[buzz sawyer]

I've seen exhaust screens plugged up and cause low power but not no start but check it anyway. 130 is all I ever get on the 017, 170, 171 so I agree, you should be fine there. The only other thing I can think of is timing - maybe the flywheel key is damaged?

 

[L34]

+1 on key.
As above on screen.
Usually start but won't rev.

 

[Vintage Engine Repairs]

When you put fuel in, you have choke off correct? And full throttle? 130 psi should certainly be enough compression even though it’s on the lower side. Just crossing t’s and dotting I’s so we’re on the same page

 

[a. palmer jr.]

I checked the muffler and there's no screen in it so someone took it out. As for the flywheel, I got another saw to work on and never got back to it but I will and soon. When I pull the starter on the 017 it doesn't even try to hit. I had a similar one once where someone had put on the wrong flywheel, I think from a MS250 or something and it threw the timing off about 90 degrees. The coils are in a different place on the 017 compared to the 250.

 

[a. palmer jr.]

When you put fuel in, you have choke off correct? And full throttle? 130 psi should certainly be enough compression even though it’s on the lower side. Just crossing t’s and dotting I’s so we’re on the same page

Yeah, I try to not flood it. Even if you flood one it will pop a little bit; this one does nothing.

 

[Vintage Engine Repairs]

Yeah, I try to not flood it. Even if you flood one it will pop a little bit; this one does nothing.

I suggest you look into spark timing, strength and consistency.

 

[a. palmer jr.]

I suggest you look into spark timing, strength and consistency.

I already did that, it had a strong spark, but I didn't check the timing of it. That comes next. I've already changed one flywheel this year on a little Stihl saw because of a sheared key. Maybe I have another one.

 

[a. palmer jr.]

I checked the flywheel and coil today the key was intact on the flywheel, part number 1130 400 1200B. The coil numbers kinda smudged but looked like 1130 1300. There were other numbers on both but I assume they were manufacturers numbers for date, etc. The flywheel was on nice and tight so nothing seemed amiss there. I guess I could find another module to try. It had a nice healthy spark when I tested it.

 

[stihltech]

You need to check that the motor is tight in the housing, the case sealant is not leaking, and intake boot is not split or out of plate. Probe the pulse passage and check to see it is open and actually delivering a pulse.
As far as spark, not likely. Yes I could be wrong, but you would have a really rare one there.
Is the plug wet? With all the cranking and addition of fuel, it should be really flooded.
Try one more thing- pull the plug, crank the saw over holding it upside down. and the throttle wide open. Then leave the plug out, set it upright and walk away for a couple days.
When you return, put the plug back in. Crank it a few times with the choke off but on fast idle. If no start, try it like any saw- choke on, pull no more than 4 times, choke off and fast idle, pull away.
Restarted more than a few saws doing this.

 

[a. palmer jr.]

You need to check that the motor is tight in the housing, the case sealant is not leaking, and intake boot is not split or out of plate. Probe the pulse passage and check to see it is open and actually delivering a pulse.
As far as spark, not likely. Yes I could be wrong, but you would have a really rare one there.
Is the plug wet? With all the cranking and addition of fuel, it should be really flooded.
Try one more thing- pull the plug, crank the saw over holding it upside down. and the throttle wide open. Then leave the plug out, set it upright and walk away for a couple days.
When you return, put the plug back in. Crank it a few times with the choke off but on fast idle. If no start, try it like any saw- choke on, pull no more than 4 times, choke off and fast idle, pull away.
Restarted more than a few saws doing this.

I've tried that also on other saws and it has worked. I'll go out tomorrow and try to start it first and if it doesn't start I try the turning it over method. I don't think it has a seal problem because fuel is in the chamber and it should at least pop once or twice even if it doesn't start. I'm kind of leaning toward a defective ignition module that produces spark but maybe it's delayed? I think I may have another module around here someplace.
I'm kind of wondering if any 017, 018 module will work, this appears to be an old saw. Any module I would have would probably be newer.

 

[Vintage Engine Repairs]

I've tried that also on other saws and it has worked. I'll go out tomorrow and try to start it first and if it doesn't start I try the turning it over method. I don't think it has a seal problem because fuel is in the chamber and it should at least pop once or twice even if it doesn't start. I'm kind of leaning toward a defective ignition module that produces spark but maybe it's delayed? I think I may have another module around here someplace.
I'm kind of wondering if any 017, 018 module will work, this appears to be an old saw. Any module I would have would probably be newer.

You tried putting fuel into the spark plug hole directly?

 

[a. palmer jr.]

You tried putting fuel into the spark plug hole directly?

Yes, I've done that to this one and it didn't hit. Kinda why I thought it might have an ignition problem even though it had spark and compression. It looks like the coil and flywheel are the right ones for the saw but maybe the module might be defective, throwing spark out at the wrong time. Other than that I'm kinda clueless at this time. By the way, the fuel I'm using is okay in other saws so it's not a fuel issue. Might try a third spark plug.

 

[Bob Hedgecutter]

Saws with a choked up spark screen will fire, will at least pop- may not run- but that is now off the table.
So we go back to the good old four- fuel and air, entering the chamber at correct volumes- good strong spark- reasonable compression- and the timing of said spark.
If all those ducks are in a row- massive air leak will stop a saw from firing if all the above is correct.
Clamshell- so quite possibly loose engine pan as suggested above.

 

[VinceGU05]

I checked the flywheel and coil today the key was intact on the flywheel, part number 1130 400 1200B. The coil numbers kinda smudged but looked like 1130 1300. There were other numbers on both but I assume they were manufacturers numbers for date, etc. The flywheel was on nice and tight so nothing seemed amiss there. I guess I could find another module to try. It had a nice healthy spark when I tested it.

yes the flywheel is the correct number. and is used on 019 T and 190 T
the ignition module 1130 400 1302 which is used on 017 018 170 180

 

[L34]

might not be firing under compression.
had this before.

 

[Old2stroke]

might not be firing under compression.
had this before.

Yep, does happen, this is where timing light comes in handy. If you hook it up with the trigger strapped "on", due to the inductive pickup, the light will only flash if spark current has gone through the HT lead (doesn't necessarily mean the spark occurred at the plug gap) and it is so bright you can easily see it anywhere. Good way to check for spark under actual starting conditions without introducing another spark gap or fooling around with the plug HT lead cap. Can also be used to check timing if that is a suspect.

 

[a. palmer jr.]

I was just out in the garage briefly and tried it again with a small bit of fuel in sparkplug hole and it wouldn't fire a bit, choke on or off. Just to be sure I'll probably mix some more fresh fuel and try it again but I'm pretty sure the fuel I'm using is okay, 90+octane non ethanol 40:1. I'm still leaning toward a defective module though.

 

[Bob Hedgecutter]

I was just out in the garage briefly and tried it again with a small bit of fuel in sparkplug hole and it wouldn't fire a bit, choke on or off. Just to be sure I'll probably mix some more fresh fuel and try it again but I'm pretty sure the fuel I'm using is okay, 90+octane non ethanol 40:1. I'm still leaning toward a defective module though.

Have you actually pressure and vacuum tested the saw?

 

[a. palmer jr.]

Have you actually pressure and vacuum tested the saw?

No, not yet, just compression. I was hoping to avoid going too deeply into this since it's not mine and it appears to be not worth much more than $100. I have another problem saw that I'm working on at the same time, a ms250 that's about like the 170 but I have had it running. Someone before me messed up the carb a bit so I'm tinkering with that in my spare time.