My dad has a hard starting 084. Any ideas?

[andydodgegeek]

I am asking a question for my dad, he doesnt have access to or know how to use a computer. He has a Stihl 084 with a 41" bar (will be mine someday), and it is extremely hard to start. Here is what it does. Push in compression release and start pulling cord, once cord is out about 4" compression release pops out. Alot of the time you will try pulling it over and it will try to remove your hand or arm when it rips the pull cord out of it. He and I are thinking the timing is off, like it is firing a little soon. Is this a common problem? He says it used to start easier thinks maybe at one time he may have hit chain brake accidentally when saw was running at high rpm, could this have damaged it? Does fly wheel have key way, and could it be damaged? I told him I would ask my chainsawing buddies, that means all of you. Where should I start? He did put in a new compression release button after someone told him to and it made no difference. Thanks in advance you folks are very helpfull.

 

[jbighump]

sheared key is what im thinking check it out,,,opcorn:

 

[gink595]

Maybe it is his starting habits? Does he pull it to TDC before he gives a big ole yank? if it is at BDC and he yanks it, it will yank back. My 880 has given me sore hand one or twice in a row:hmm3grin2orange:

 

[Jacob J.]

It could be that the flywheel key is damaged and the flywheel has moved, that's a sound theory. It could also be that the compression release valve is coked (carboned) up. Also, if the compression release gets worn down it will get very weak and pop out with the slightest pressure. So those are all things to check.

Pull the flywheel and check the timing.
Pull the compression release and clean it out real good and check to see how much snap it has.

 

[mdavlee]

Some of those big saws pop the decomp out seems like on every pull. Will it run fine the way it is?

 

[ECsaws]

Maybe it is his starting habits? Does he pull it to TDC before he gives a big ole yank? if it is at BDC and he yanks it, it will yank back. My 880 has given me sore hand one or twice in a row:hmm3grin2orange:

You cant sissy crank it :msp_smile:

 

[Jacob J.]

You cant sissy crank it :msp_smile:

An 084 in good repair is not very hard to start, unlike a Mac kartsaw which will eat your tendons for a light snack.

 

[andydodgegeek]

You can get it started and it seems to run good but it is a nasty one to start. My dad is 74 years old and has been chainsawing since the 60s, he isnt new to starting big saws.

 

[TonyRumore]

Sounds like it just needs a new compression release.

 

[andydodgegeek]

Already replaced compression release, no difference. Tried another compression release from another saw, no difference. I am going to try pulling flywheel see what I can see.

 

[ECsaws]

An 084 in good repair is not very hard to start, unlike a Mac kartsaw which will eat your tendons for a light snack.

His is in good repair, its just not quite how stihl made it....

 

[Stumpys Customs]

I will second or third?? checking the flywheel key.:msp_thumbsup:

 

[gink595]

If I remember right the 084 I rebuilt had two positions you could locate flywheel.

 

[gink595]

His is in good repair, its just not quite how stihl made it....

It got the oriental massage treatment:hmm3grin2orange:

 

[andydodgegeek]

If I remember right the 084 I rebuilt had two positions you could locate flywheel.

Any one else confirm this. I dont know just asking.

 

[zogger]

Why would that compression release valve pop out after only four inches of pull? Shouldn't it stay in-making it easier to pull- until the thing really fires and starts to run, a good full yank? Ask you dad how it used to work, that just doesn't seem right to me, as in, what would be the point of even having it if it didn't work to relieve some compression for the starting sequence?

disclaimer: not familiar with that saw, just wondering on general principles

 

[Jacob J.]

There is one 084 flywheel that has dual keyways, but there's two others that don't.

 

[gink595]

Why would that compression release valve pop out after only four inches of pull? Shouldn't it stay in-making it easier to pull- until the thing really fires and starts to run, a good full yank? Ask you dad how it used to work, that just doesn't seem right to me, as in, what would be the point of even having it if it didn't work to relieve some compression for the starting sequence?

disclaimer: not familiar with that saw, just wondering on general principles

Thats why I think the piston is on it's way up when he is pulling it instead of going down from TDC???

 

[andydodgegeek]

He does pull it to tdc before he yanks it.

 

[TonyRumore]

I just tried both of mine and if you pull the starter like you're starting an 036 or something, the compression release will stay down (on). If you put some serious a$$ behind it, the release will pop up about half way through the pull stroke. Pulling it with the compression release off would probably break the rope, handle, or dislocate your shoulder.

Tony