would running 87 octane in a trimmer that require 89 cause hard starting?

[The motor guy]

I have echo equipment that I use commercially. I've had a complaint about their latest trimmer, that over time the pull cord becomes very notchy when pulling. 3 or 4 times a day it feels like the trimmer locked up and it's very difficult to pull the cord. I have two that are like this, just bought a new one and it's a night and day difference, pulling the pull cord. It's not getting hung up like the old ones do. I mean it has just a tad, but no where near as bad as the older ones. The only difference is I decided to use 93 octane, but I find it hard to believe the fuel is what's making the difference. Opinions?

 

[Barkleymut]

My 2601 Echo has run just fine on 87 octane for over 25 years. Guessing the difference is in the recoil spring.

 

[dnewton3]

Octane is the resistance to pre-detonation. So in THEORY ... the lower octane fuel should actually ignite a tad bit easier; it would have lower resistance to igniting.

All I have ever run in mine it 87 gas in all my OPE. Never had one issue regarding starting.

 

[The motor guy]

My 2601 Echo has run just fine on 87 octane for over 25 years. Guessing the difference is in the recoil spring.

Yeah they don't use those dampner springs anymore on the newer stuff.

 

[The motor guy]

Octane is the resistance to pre-detonation. So in THEORY ... the lower octane fuel should actually ignite a tad bit easier; it would have lower resistance to igniting.

All I have ever run in mine it 87 gas in all my OPE. Never had one issue regarding starting.

oh it runs great once it's started, I just don't think a trimmer should be as hard as a chainsaw to start.

 

[RDY4WAR]

The difference in octane shouldn't cause hard starting. Vapor lock, flooding, fuel not vaporizing (cold weather), water in the fuel, clogged jet in the carb, and some other factors can cause hard starting. Spray a little ether down its throat (though not much).

Octane is the resistance to pre-detonation. So in THEORY ... the lower octane fuel should actually ignite a tad bit easier; it would have lower resistance to igniting.

All I have ever run in mine it 87 gas in all my OPE. Never had one issue regarding starting.

In theory, yes, but not in real world conditions of a combustion chamber. The arc is hot and powerful enough to ignite the fuel regardless of the octane. It's just the auto-ignition point of the end gases, ahead of the flame front, that is reflected with the octane rating.

 

[racer12306]

Ever run 112 octane in OPE, now that's a bit of hard start

We had some old race gas to burn up and burned it through the mower, it definitely cranked more before it started.

 

[Brian123]

I have echo equipment that I use commercially. I've had a complaint about their latest trimmer, that over time the pull cord becomes very notchy when pulling. 3 or 4 times a day it feels like the trimmer locked up and it's very difficult to pull the cord. I have two that are like this, just bought a new one and it's a night and day difference, pulling the pull cord. It's not getting hung up like the old ones do. I mean it has just a tad, but no where near as bad as the older ones. The only difference is I decided to use 93 octane, but I find it hard to believe the fuel is what's making the difference. Opinions?

Maybe Google Echo Pull Cord Problems and check out some of the Videos on YouTube.

 

[Zee09]

Shell gas gave me hard starting in everything I have. (OPE)
The station was local and once I switched the issues went away.
I use 87 in everything too. Try a new brand of gas and see.

 

[BMWTurboDzl]

Ever run 112 octane in OPE, now that's a bit of hard start

We had some old race gas to burn up and burned it through the mower, it definitely cranked more before it started.

Yikes. So you weren't concerned about the lead?

 

[RDY4WAR]

Ever run 112 octane in OPE, now that's a bit of hard start

We had some old race gas to burn up and burned it through the mower, it definitely cranked more before it started.

I ran VP C25 (118 octane) through a push mower, and it fired on the first pull. That's due to C25 being a highly volatile, fast evaporating and burning fuel. The 112 you used was likely a boost/nitrous favored fuel with a much higher temperature distillation curve thus not vaporizing readily at ambient temp on startup. Fuel cannot ignite as a liquid. It must be a vapor.

 

[walterjay]

I used to have hard starting on my 2 cycle engines. Switching to a higher octane fuel made a remarkable difference.

 

[JohnnyG]

It's possible IN THEORY that you might be getting pre-ignition on startup. I'd say this would be more noticeable on a warm engine, but other than mechanical issues, it's the only thing I can think of that would cause the notchyness when pulling the starter cord.

 

[2005jettatdi]

Not Echo, but my Stihl Farm Boss chainsaw said to run it on 89 octane gas. I thought that was silly and ran it on 87 octane at first. It would not run well. I switched to high octane and it runs just fine. I won't try to explain it since I don't understand it.

 

[97prizm]

I have echo equipment that I use commercially. I've had a complaint about their latest trimmer, that over time the pull cord becomes very notchy when pulling. 3 or 4 times a day it feels like the trimmer locked up and it's very difficult to pull the cord. I have two that are like this, just bought a new one and it's a night and day difference, pulling the pull cord. It's not getting hung up like the old ones do. I mean it has just a tad, but no where near as bad as the older ones. The only difference is I decided to use 93 octane, but I find it hard to believe the fuel is what's making the difference. Opinions?

It's most likely the recoil spring going bad which can cause the pull cord to not retract correctly causing binding. As far as octane goes my Stihl reccomends no Lower than 87 but if I remember suggested premium. My Stihl fs-38 definitely runs smoother and has better throttle response with premium. Remember gas trimmers tend to be fairly high compression and air cooled. I run 100LL with 2 stroke mix from the airport. It's only a gallon or two a year for me.

 

[Rand]

So a new one works right and its on 93 and old ones dont work right on 87..
there is no cause and effect there.
its not the 87 gas.
How do you run your trimmers? full out? partial throttle somewhere in-between?

I run 100LL with 2 stroke mix from the airport. It's only a gallon or two a year for me.

Lead fumes are not what I want to breathe in. Do you have to clean lead off the spark plug electrodes? or does it all just blow out in exhaust?

 

[Skippy722]

My Husqvarna 525L calls for 87 minimum but also says “When working at continuous high revs a higher octane rating is recommended.” It’s never seen anything less than 94 (VP premix because I use a gallon or less a year) and never had an issue starting.


I think it’s just parts wearing out in your case.

 

[The motor guy]

It's possible IN THEORY that you might be getting pre-ignition on startup. I'd say this would be more noticeable on a warm engine, but other than mechanical issues, it's the only thing I can think of that would cause the notchyness when pulling the starter cord.

If it sits for 10 minutes it's usually when it will do it.

So a new one works right and its on 93 and old ones dont work right on 87..
there is no cause and effect there.
its not the 87 gas.
How do you run your trimmers? full out? partial throttle somewhere in-between?


Lead fumes are not what I want to breathe in. Do you have to clean lead off the spark plug electrodes? or does it all just blow out in exhaust?

The dealer said they do it because people just lolly gag about with them and don't give them enough throttle, so they carbon up. Pffft, I take the guards off mine, they get plenty hot.

 

[The motor guy]

If it sits for 10 minutes it's usually when it will do it.

The dealer said they do it because people just lolly gag about with them and don't give them enough throttle, so they carbon up. Pffft, I take the guards off mine, they get plenty hot.

I've run them full tilt for an hour straight, which makes me wonder, maybe they got too hot and seized or something.

 

[4WD]

Not Echo, but my Stihl Farm Boss chainsaw said to run it on 89 octane gas. I thought that was silly and ran it on 87 octane at first. It would not run well. I switched to high octane and it runs just fine. I won't try to explain it since I don't understand it.

The only thing I run “brand can” fuel in - I use corded and cordless saws more often - but want that Stihl to start when needed …