If you do not make it a habit of running it out of fuel when you put it away varnish builds up in the carb, a trick I learned that has worked on some is to get it running let it warm up so you can start it easily. Now mix 1oz oil and 5oz acetone dump out the fuel in the tank fill it with the new mix, it should start right up on the little gas left in the lines. You will smell when it is running on hte new mix, run it dry then refill with regular fuel. It does not work in all cases but has saved me from pulling apart a few carbs.

Phil

 

Thanks, I do have some acetone, does that have a good shelf life? I'd bet my can is at least 5 years old. I don't use it much, can't even remember what I purchased it for.

What about 1 oz oil and 5 oz Seafoam? Seafoam has a lot of advocates on the collection of forums. I have run some stiff Seafoam mixes and it has helped in the past, but not this fall.

 

I have had a Mantis tiller for at least 5 years and it starts on 1st pull every time and runs great. I have 7 or 8 of these type of tools and if they all started and ran like the Mantis I would be 1 happy camper.

 

Interesting on engine experience, I mean just the opposite experience. I have read on this forum several complaints about the "industrial strength" 2-cycle engine used on the Mantis... and strong recommendations to pay a little more and get a Mantis with a 4-cycle engine.

The only other engine I have that is anywhere as finicky is my 2 cylinder 9.9 HP 2-cycle OMC Evinrude outboard. Its main problem is running at full power, not starting. Once running it will start with half-a-pull, but will sometimes not deliver full power until it has been run for 10 minutes... assume carb problems here too, and Seafoam has been only a minor help, maybe no help.

 

I bought a Mantis used at an auction that hadnt been started in years and I thought it was "just me"; this carb has been dunked and kitted twice; I think it's time for a different carb.

 

Mine had started 1st or 2nd pull till this spirng. I finally put a Carb kit in it last month and it runs and starts great again. I am using Quick Silver now and am thinking of switching to Omni 2. :thThumbsU For the first 4 years I never drained or run it out of gas for the winter and for that long to go with no problems I thoughtwas very good.

 

First thing that comes to mind with a 2-cycle that doesn't run well is leaky crankshaft seals. Any chance these engines might have inherently bad seals?

I would expect to see some oil seepage around the seals if they are leaking, but probably not much and especially so if they're running 50:1 or less oil.

 

A Mantis 2 cycle tiller will have an ECHO manufactured engine on it, the older ones that pre=dated the ECHO name were branded Kioritz (echo's parent company).

Echo engines are among the easiest starting, most reliable 2 cycle engines produced, and always have been.

If it doesnt start on 1-2, maybe 3 pulls if sitting a few months, there is a problem. My 20 year old mantis with its old old engine, no primer bulb, starts on 3 pulls from a dead sit...

Being a certified Echo service tech, I service/repair around 20 mantis tillers of varying ages each year...the powerheads are nearly bulletproof, Ive only had 1 that had too much damage to repair..and it had been run for 12 years with no air filter foam insert, ate the rings up.

I would start with a tuneup. New plug, fuel filter, carb kit, fresh fuel in a clean tank...also check the muffler for being plugged up.

 

also...

50:1 echo power blend, mixed with 92octane gas, with NO ETHANOL CONTENT....

They love it...we get max power and longevity on this mix, on all makes of equipment.

 

I can't find any gas around here without ethanol added. Well, other than avgas.

 

You can make your own with high octane gas from the gas station by removing the ethanol from the gas by adding water. Youtube videos will show you how. Start with highest octane because removing the ethanol from 87 will result in a lower than 87 octane gas.

 

My mantis has been running strong for 10 years with no special treatment. When it finally blows up, I'll let you know what went!

 

Update, with a happy face ":trink40: on my no power Mantis 2-cycle. As I may have posted the machine is about 2 years old and has no more than 15 hours run time on it.

I pulled it out of the shed to till my small garden, really to see if I could get it to run.

I put in fresh gas with a heavy dose of Seafoam, hoping that would clean out the problem. I took a few pumps on the primer and a a few pulls (maybe 5 or 6) on the cord with full choke to get it to kick over. It would not start without a choke, but it did become very easy to start at full choke. I kept it running and tried to move the coke back and it would die.

I then looked at the manual and decided to try to adjust the carb. Set the high speed jet (red) at full open (counter clockwise) and the low speed jet (white) at about mid-point. It will rotate only about 120 degrees. The machine then started and did better with the choke off. I opened the low speed a bit more and it started to run better and when warmed up (2 minutes) it ran at full throttle. I took it to the garden and it developed (I estimate) full power. I tilled the garden, taking about 1/4th a tank of gas... yes small garden. I will add more fuel/oil and till again. It may run even better with a normal dose of Seafoam.

Funny in my mind why adjusting the low speed carb jet corrects a high RPM problem. I have a similar problem on my 9.9 hp Eveinrude outboard.. I'll look up how to adjust its carb.

So, the Mantis engine may give me some good service after all.

 

:congrats::congrats::congrats:

 

It's difficult to get to a clean top end if your bottom end circuit is too lean to allow a good transition. Low speed jet on a bike reaches considerably higher into the RPM band than most appreciate until they fatten it up a mite (especially since the smog Nazis & gasahol types took over).

 

One thing that I have found that happens a lot on chainsaws,I don't know if they use them on all 2cyl engines or not but it would be worth a look.Under the muffler,they use a spark arrestor that is nothing more than a screen that the exhaust needs to go through before it goes to the muffler.The little holes in those screens get clogged with carbon,the more holes that get clogged,the less power you have.I've fixed 6 or 8 saws in the past couple years that all that was wrong with them was that those screens were clogged.You can take them out and clean them usually without too much trouble and the engine will run fine again.

 

These as with most newer small 2 cycles are set very lean from the factory. I repaired 4 Mantis's last year and 3 needed carb overhauls. You should even go as far as cutting off the limiter caps from the adjustment needles to get the full and proper tune on these engines. The only way to really get em' dialed in. I've got 2 nice little tillers within the last year for free. The last one needed a new piston/ring as the p.o. ran it without the air filter installed. Not too smooth in my book. Luckily I just happened to have a nice lightly used 21cc slug from an Echo SRM-210 trimmer laying around. Popped it in and was back-n-bidness.

 

jerry_nj, thanks for the post, it offers some great discussion on 2-stroke gas & Oil. I have seen several threads related to Gas & Oil mixtures which prompted me to do some research and I started a separate forum thread.

In this thread I am looking for MTF user input on Gas & Oil ratio mixtures and keeping information about their gas tool items. I am hoping some of the users posting to your thread could assist me as well. You can access the thread's link by clicking here.