Mantis tiller won't run

[Southeast Overland]

I have one of those little Mantis tillers that I can not get to run.

I bought it for $5 at an estate sale about 2 years ago. It looked like like crud. Old gas was still in the tank and about as thick as jelly but for $5 I couldn't pass it up. I took it to a small engine repair shop and told them to see if they could get it running. When I got it back it ran OK but really liked to be at full throttle to stay going. It didn't like to idle. I meant to take it back but never got around to it.

Fast forward a year to this past weekend. I decided to try and tune-up all my yard equipment. I got my hedge trimmer working great. The old beat-up lawn mower runs fine anyways but I still tuned it a bit. I'm waiting on some gaskets for my blower and then jumped on this tiller and got no love.

The tiller wouldn't start so I drained the gas and put in new gas, installed a new spark plug, the air filter looks OK but I'm picking up a new one anyways. I pulled the carb and cleaned it out well. It looks like the repair shop put a new carb on. I cleaned out all the old gas from the carb and found what appeared to be a little bit of thin plastic blocking part of the carb which I removed. I put everything back together exactly like I took it apart and the sucker wouldn't start.

If I let her sit for a few hours and then give her a pull she will turn over for maybe a second and then she won't even attempt to start for anything.

Does anyone have any ideas? I'm too dang broke to take it to a shop to get fixed. I might take it back to the original shop if I have to (1.5 hours away but near my mom's house) and see if they can figure it out.

Anything?

Oh, I even sprayed starter fluid in the carb and it wouldn't start. I sprayed just a brief mist to a few seconds of starter fluid and nuttin'. Do you think I'm not getting spark?

 

[D'Animal]

How old is it?

The original Mantis Tillers used Kioritz (Echo) engines that had points in them. You may need to clean and/or adjust them.

I would check the compression before I spend any money on it.

Hard starting and only runs WOT (Wide open Throttle) would make me believe that rings may be worn and you do not have at least 100lbs compression, which is what it takes to make most standard 2-cycyles run at idle.

 

[Southeast Overland]

I don't know how old it is but it is old enough not to have a primer bulb. My grandfather has the same tiller but his is only about 5 years old or so and does have a primer bulb.

Well hell...

 

[D'Animal]

Most hand held equipment has a primer bulb.

They started using them back in the mid 1970's.

The bulbs on the newer equipment are purge bulbs, they are not true primer. They just purge the air out of the system.

Check your fuel line for cracks as well as the primer bulb.

 

[Southeast Overland]

Fuel line was replaced ~ 1.5 years ago and looks good.

This Mantis does not have a primer/purge bulb. I'll take pics tonight.

 

[D'Animal]

Then is just has a choke lever on it.

No primer, no problem.

 

[Southeast Overland]

Then is just has a choke lever on it.

No primer, no problem.

Correct - does have a choke lever (really a pull).

 

[romegadave]

I've got the later version of the Mantis with a bulb...and it can be a PITA to start. In fact I need to crank mine tomorrow just cause these little buggars seem to be prone to aggrivation if not cranked pretty regular.

My boss has one too and he sez problems seem to always occur in the carb....I'm always checking my fuel line too since it gave trouble before.

 

[raydouble]

Did you ever replace the in tank fuel filter?

 

[D'Animal]

Have you checked the compression yet?

How old is it?

The original Mantis Tillers used Kioritz (Echo) engines that had points in them. You may need to clean and/or adjust them.

I would check the compression before I spend any money on it.

Hard starting and only runs WOT (Wide open Throttle) would make me believe that rings may be worn and you do not have at least 100lbs compression, which is what it takes to make most standard 2-cycyles run at idle.

You may have a bad crankshaft seal as well.

 

[Southeast Overland]

Did you ever replace the in tank fuel filter?

Nope - I'll replace it - could be clogged I guess. I did spray it off w/ cleaner.

Have you checked the compression yet?

You may have a bad crankshaft seal as well.

Nope - I haven't been able to do much of anything in the garage for a few weeks. I just gave the compression tester I had back to its owner. I'll pick it up again and check the compression.

Thanks again.

 

[smallmoto]

Spark Arrester Screen Clogged

Re: Mantis tiller no spark

by smallmoto » Mon Jun 24, 2013 4:40 pm
Mike,
I just finished working on a SV4/B Type 1-E Mantis Tiller that would not start/run.
Installed a new plug, no start.
Installed a new carb, no start.
Installed new fuel line/filter/breather, no start.
New fuel mix, no start.
Hmmmmmmm...................
I took off the cover to the muffler/screen spark arrester, and the small metal screen was totally clogged.
Cleaned it with carb cleaner and a wire brush.
Reinstalled screen.
Tiller now fires up and runs fine.
If this spark arrester screen is clogged, the engine can't exhaust or breath, so no start up or only idle running at best.

I cleaned the ignition coil/flywheel magneto contact plates with fine sandpaper until they were rust-free and shiny.
I set the gap to .015, Mantis recommends .014, but I hear .012-.018 will work.

Clean the contact plates, adjust gap to .014, clean the spark arrester screen in the muffler, reassemble and see what happens.

The spark arrester screen needs cleaning yearly or two, as I just had to clean the screen on my SV5/C2 which is only 3 years old...it would not start at all until I cleaned the screen.