Ms180 - Starter Kickback When Cold?

[ham]

I have an MS180c that I bought from a homeowner who used it once, it scared him, he put it away for years. I rebuilt the carb or possibly replaced it with an OEM carb (this was 4-5 years ago), tuned it, sharpened the chain, it's been a great limbing/fallen branches saw for me.

The only issue, and it's very obnoxious, is that when it's cold the starter wants to kick back. It reminds me of big bore 2 stroke dirtbike days, where you kick start it and the engine almost reverses on you.

Any insight here? I understand that this is often a timing issue, but my understanding of these is that it's almost impossible to have a timing issue. It's definitely not flooding, this will happen with no choke.

It's possible that the recoil itself is binding, but I really don't think that's the case.

I know it's a small saw, but I greatly prefer it to my ms290 due to weight and size. 95% of what I do are cutting down small trees, bushes, fallen branches, and it's perfect for that. But this kickback stuff is tiring.

 

[ZinTrees]

check the flywheel key, if its sheared it will throw timing off

super easy and cheap fix if it is the key

 

[ham]

check the flywheel key, if its sheared it will throw timing off

super easy and cheap fix if it is the key

Is there a decent manual for this thing? I assume remove recoil, remove flywheel bolt with an impact. Normal or reverse thread?

 

[singinwoodwackr]

Post in thread 'Stihl Illustrated Parts Lists (IPL)'
https://www.arboristsite.com/threads/stihl-illustrated-parts-lists-ipl.317358/post-6461561

Ray Benson will have the manual

 

[buzz sawyer]

Is there a decent manual for this thing? I assume remove recoil, remove flywheel bolt with an impact. Normal or reverse thread?

The recoil cover is a little tricky. You have to remove the oil cap and chain brake handle screw, then hold that side of the chain brake handle out of the way while pulling the cover. Flywheel is right hand threads but since you have to use a piston stop anyway for reassembly, I start with that and use a wrench. Not a big fan of impact tools on small parts. I can't imagine what else it could be besides timing. It's not a real high compression engine - 130 - 140psi.

 

[ZinTrees]

Is there a decent manual for this thing? I assume remove recoil, remove flywheel bolt with an impact. Normal or reverse thread?

Normal thread, should be 4 t27 to remove the recoil

Loosen the nut just barely off the flywheel but leaving as many threads on the crankshaft as possible, now smack the nut fairly sharply with a hammer, this will shave the whole saw sideways and pop the flywheel right off

Let me check for a manual

 

[ZinTrees]

The recoil cover is a little tricky. You have to remove the oil cap and chain brake handle screw, then hold that side of the chain brake handle out of the way while pulling the cover. Flywheel is right hand threads but since you have to use a piston stop anyway for reassembly, I start with that and use a wrench. Not a big fan of impact tools on small parts. I can't imagine what else it could be besides timing. It's not a real high compression engine - 130 - 140psi.

Poston stop? I always just zip the nut on and off with an impact driver, leave the plug in it and the compressions holds it fine

 

[singinwoodwackr]

Poston stop? I always just zip the nut on and off with an impact driver, leave the plug in it and the compressions holds it fine

I use a Makita 1/4" impact that has 4-speeds and 4 torque settings. Easy to dial it down for smaller parts.

 

[ham]

Thanks all. I've removed flywheels from these small engines before. Zip off with impact, put nut back on, put on socket+extension, rap a tap tap while holding the saw up by the flywheel.

Googling around, it looks like the flywheel has an integrated key. I'll dig into it this weekend.

 

[buzz sawyer]

I use a Makita 1/4" impact that has 4-speeds and 4 torque settings. Easy to dial it down for smaller parts.

That works fine if you have it. A piece of rope cost much less and doesn't need to be charged.

 

[TheJollyLogger]

Just throwing it out there... the ms 170/180s aren't particularly high compression saws... but... they are very lightweight as well... the OP hasn't complained about running issues, just the fact that when it gets colder the saw can "kick back" when starting. Ockham's razor, I have seen this as well with 170, 180s especially drop starting them after running larger saws... they can hang up on compression and bounce in your hand, especially compared to a larger saw with more non reciprocating mass.

If the saw runs fine once started and this is the only symptom, it could just be the OP getting accustomed to that small a saw... just a thought...

 

[ham]

Just throwing it out there... the ms 170/180s aren't particularly high compression saws... but... they are very lightweight as well... the OP hasn't complained about running issues, just the fact that when it gets colder the saw can "kick back" when starting. Ockham's razor, I have seen this as well with 170, 180s especially drop starting them after running larger saws... they can hang up on compression and bounce in your hand, especially compared to a larger saw with more non reciprocating mass.

If the saw runs fine once started and this is the only symptom, it could just be the OP getting accustomed to that small a saw... just a thought...

It does run fine once started. I start saws on the ground. It might not be pre ignition kick back but it sure does feel like it. First pull is fine. Second or third pull it yanks the starter handle right out of my hand.

 

[ham]

Also, I had an ms170 that didn’t exhibit this behaviour at all

 

[ZinTrees]

if the flywheel key is intact, then id put an elastostart handle on it just to help a little
perhaps try pulling just a little harder/faster, you might be pulling it just slow enough that momentum isnt carrying the piston past TDC?

 

[blknblu]

I have a MS180 and can verify it should start easily, with no kickback.
Something is definitely off.

 

[grizz55chev]

It does run fine once started. I start saws on the ground. It might not be pre ignition kick back but it sure does feel like it. First pull is fine. Second or third pull it yanks the starter handle right out of my hand.

Check the coil to flywheel gap, use a business card to set the gap.

 

[coffeebrk]

Have you pulled muffler when starting cold? Just eliminate carbon build up adding to your issue.

 

[stihltech]

This can be anything from a module not starting in a reduced timing mode to fuel to a tired operator to improper starting procedure. I would try a different module. I am lucky as I have many parts saws.

 

[singinwoodwackr]

This can be anything from a module not starting in a reduced timing mode to fuel to a tired operator to improper starting procedure. I would try a different module. I am lucky as I have many parts saws.

Module, on a 170?

 

[stihltech]

If it is electronic it is a module, not just a coil. Modules have electronics inside to replace points and set advance. A coil is used on an ignition with points or a separate trigger module.