So I am hoping someone can help me here - I recently got a used Remington Outlaw RM4620 20" saw and basically the problem is it will not stay running. It starts easily but then cuts out after a few seconds. If I give it gas, it will run a little longer but eventually it cuts out maybe after 20 or so seconds even with full throttle. So far I have: Replaced the fuel filter and fuel line that runs from it into the carb, drained the fuel tank and replaced it with fresh gas, replaced the air filter, cleaned out the spark arrester, and cleaned out the bar oil channel (so that is working fine at least). Still it is happening. I even can remove the air filter and it happens. Choke and intake seem to work and look clean. Spark plug looks OK. It sounds to me like a fuel delivery problem. Any ideas? Do I have to take the carb out, clean or rebuild it? Could it be the mixture or idle speed? When it start, it appears to idle briefly at a reasonable rate. It was not expensive and I would rather not put much money in it. Thanks
Saw starts right up but then cuts out
- Thread starter Chintzel
- Start date
So it came to you secondhand?
Idle briefly - at a reasonable rate?- so it starts idle increases a bit then dies?
First thing to do is take the muffler off, cycle the engine by hand and look at the piston through the exhaust port- if it is all blackish and scratched/scored vertically up the piston face- its toast.
From what you are describing, I would expect the engine has developed an air leak somewhere, been run lean and burned out the piston to a point of very little compression.
Idle briefly - at a reasonable rate?- so it starts idle increases a bit then dies?
First thing to do is take the muffler off, cycle the engine by hand and look at the piston through the exhaust port- if it is all blackish and scratched/scored vertically up the piston face- its toast.
From what you are describing, I would expect the engine has developed an air leak somewhere, been run lean and burned out the piston to a point of very little compression.
Yikes. That would suck. Well, it was only 75$. And yes, bought it second hand. It idles for a few seconds then cuts out - if I rev it it will run a bit longer but even at full throttle it does not run more than about 20-30 seconds. Tomorrow I will do what you suggest and cross my fingers!
Muffler off and check the piston is the first thing I suggest to most.
There is no point throwing parts at a saw, or guessing problems if the engine internals are toast.
Indeed it is a good check to make at point of sale- before you hand over cash- take a few basic tools, remove the muffler and check the piston- if it looks damaged- say no thanks and walk away with all your money still in your wallet.
Check and see- it might be all good, in which case we start looking at other possibles.
There is no point throwing parts at a saw, or guessing problems if the engine internals are toast.
Indeed it is a good check to make at point of sale- before you hand over cash- take a few basic tools, remove the muffler and check the piston- if it looks damaged- say no thanks and walk away with all your money still in your wallet.
Check and see- it might be all good, in which case we start looking at other possibles.
Excellent photos- would have been better to have a second, one showing the top of the piston and rings in the grooves- but nice all the same.
For my money, thats damage- the vertical streaks look to be transfer of the heated piston to the cylinder walls, but certainly not the worst I have seen and may possibly be savable if new piston rings can be found.
Will entail a complete strip down of the upper of the saw, cylinder off- piston cleaned up and re ringed, all transfer cleaned off the inside of the cylinder and reassembly. Hopefully in amongst all that you can figure out why it happened and find an area that was leaking- like a loose engine pan, crank seals, leaking intake or decide it was just lean saw settings or straight/low oil mix fuel was used and correct anything found or it will just do the same again.
You have to decide if this is too daunting of a task, or to uneconomic to try.
For my money, thats damage- the vertical streaks look to be transfer of the heated piston to the cylinder walls, but certainly not the worst I have seen and may possibly be savable if new piston rings can be found.
Will entail a complete strip down of the upper of the saw, cylinder off- piston cleaned up and re ringed, all transfer cleaned off the inside of the cylinder and reassembly. Hopefully in amongst all that you can figure out why it happened and find an area that was leaking- like a loose engine pan, crank seals, leaking intake or decide it was just lean saw settings or straight/low oil mix fuel was used and correct anything found or it will just do the same again.
You have to decide if this is too daunting of a task, or to uneconomic to try.
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Yikes. Probably not worth the time or money since the site isn’t worth a very much and if I were to attempt this, it would be more of a learning/fun product than anything else since I’ve nrbrt done anything like that before. Thanks for the info. Do you think theoretically anything else could be the cause besides this? Something relatively simple? Like the idle mixture or something?
It could be carbon build up in the exhaust port, heavy carbon deposits right at the interface where cylinder becomes port- build up of peaks there can score the piston- usually nick the ring grooves and trap the rings after a while. Near as bad as a lean running saw, usually caused by low grade oils and incorrect mix ratios/tuning.
However you exhaust port, though oily looking- does not seem to be heavily carboned.
Can still be a learning/fun project and can be done here- lots of photos help. What have you to loose- if you do get it to run as is- it will burn up bad if its an air leak. So you do not really have a "current resale value", so what is there to loose from pulling it apart and learn while you go?
One easy test to see if the rings are trapped or compression is down to the point the saw will not run- is to remove the sparkplug, pour about a teaspoons worth of oil in the plug hole on top of the piston, put the plug back in, swill the oil about to coat the top of the piston and cylinder walls- try to start the saw.
If it runs- it will SMOKE! But if it runs it proves the compression (or lack thereof) is your problem.
However you exhaust port, though oily looking- does not seem to be heavily carboned.
Can still be a learning/fun project and can be done here- lots of photos help. What have you to loose- if you do get it to run as is- it will burn up bad if its an air leak. So you do not really have a "current resale value", so what is there to loose from pulling it apart and learn while you go?
One easy test to see if the rings are trapped or compression is down to the point the saw will not run- is to remove the sparkplug, pour about a teaspoons worth of oil in the plug hole on top of the piston, put the plug back in, swill the oil about to coat the top of the piston and cylinder walls- try to start the saw.
If it runs- it will SMOKE! But if it runs it proves the compression (or lack thereof) is your problem.
IF it starts it proves somewhat that compression is low (the oil provides temporary coating and "thickness" to the cylinder walls- taking up the missing slack) and low compression is bad- well bad to the point of needing at least a new set of rings minimum and the cylinder needs removed to accomplish that.
Get someone to video it if you do give it a try- if a teaspoon of oil doesnt do it- try two!
Eventually the oil will form a hydrolock and near tear the starter handle through your fingers- you need to drain some out then......
Eventually the oil will form a hydrolock and near tear the starter handle through your fingers- you need to drain some out then......
Nope, it needs fuel to run.
OK so the test was a success. Or should I say failure? It started up pretty easily and smoked like mad. Do you think the main thing that I need is a new piston ring? Or is something more likely shot as well?
Excellent- but no video?
I do not know what you "need" nor do you until you dig in there- BUT what it does is confirm the saw has low compression and needs something done to correct that.
So you have to pull the cylinder- might be just a new ring is needed and clean up the piston, or it might need a new piston and ring, or it might need a new cylinder piston and ring.......
You just don't know till you go look at the internals to see how good/bad things are.
Plus you need to decide why it scored the ring/piston up- was is bad fuel mix, air leak, loose engine pan, bad oil seals on the crank, bad manifold, bad impulse, tuned lean from the factory to meet EPA and worked hard with a blunt chain- you have to find the culprit and correct it- or any repairs will chew out the top end again and possibly in less than a tank of fuel.
your choice- is it worth your time and any cost of parts to have a box store consumer grade saw?
But, if you are going to pull it apart- take video or photographs as you go so you have a reference to put it back together correctly.
Get some snap lock plastic bags to put parts in and a vivid pen to write on the bags what they contain - try to keep all parts together- like all the clutch parts and that side of the saw in one bag, the starter side and ignition parts in another, airbox parts and carb in another etc.
But, if you are going to pull it apart- take video or photographs as you go so you have a reference to put it back together correctly.
Get some snap lock plastic bags to put parts in and a vivid pen to write on the bags what they contain - try to keep all parts together- like all the clutch parts and that side of the saw in one bag, the starter side and ignition parts in another, airbox parts and carb in another etc.
I think when I get a chance I will take it apart - no harm in seeing what is going on. It will be an interesting exercise at the least. And I will record it and post what I can. Certainly probably not worth investing in a bunch of parts unless they are very cheap but at least I could get a feel for what is going on with it - for future reference. Thanks!
