Mantis tiller - dies when throttle is pulled

[2manyrocks]

Not having a Mantis, I can't say for sure, but most 2 stroke carbs I've seen have four screws holding a plate on them that contains the fuel pump diaphram. I'd look for a parts schematic for your model and see if there isn't a carb kit for it.

Today's rotten gas will foul a carb in a month.

While your at it, be sure to check all your fuel lines because methanol will ruin them too, if they weren't designed for it.

 

[Bird]

I guess I am going to buy a new carb. If I am understanding it correctly there is no way to pull apart the carb, as it is one single block.

Not having a Mantis, I can't say for sure, but most 2 stroke carbs I've seen have four screws holding a plate on them that contains the fuel pump diaphram. I'd look for a parts schematic for your model and see if there isn't a carb kit for it.

I figured Paul & I had the same model, but that may not be the case. However, page 17 of my owner's manual shows "SV-5C/2 ENGINE PARTS ASSEMBLIES CARBURETOR" and shows an exploded view of the carb and a parts list (38 parts) which includes a part number A021001090 for "Carburetor - C1U-K82" for the whole thing and part number 12530013120 for "Repair Kit - includes items 24-33" so yes, you can take it apart and overhaul it if it's the same as mine.

But at least, Paul, those numbers should tell whether we have the same machine or not.

 

[Soundguy]

if it was built.. I'm surprised it can't be rebuilt.

even if a monolithic block.. there must be galley plugs for drilling the jets..e tc.

soundguy

 

[PapaPerk]

You can certainly rebuild the carb! You don't even need to do that. Just disassemble, clean, and reassemble. Should run fine after that! Good luck

 

[bilrus61]

We've had our Echo engine Mantis for about ten years. Runs great. I basically use it as a edger for our driveway and sidewalks. Get some carb cleaner and let it just idle. Check the muffler and see if a dirt dobber wasp has clogged it up. You can run some trimmer line into the muffler to clean out any wasp mud. Just a tad of mud will restrict your airflow.

 

[RonMar]

There is an internal rubber diaphram, and some acetate membranes that act as check valves. These get old and dry out/get stiff. 4 years sounds about right, if you left fuel set in it for any length of time. the rubber diaphram modulates the needle valve used above idle, so that is probably your issue.

They are actually fairly simple to overhaul. The carbs are basically similar to the walbro series carbs, if it isn't an actual one. If you google the P/N stamped on the carburettor you can probably determine the actual manufacturer. If you go onto Youtube and search walbro carb setup, overhaul or tuning, there are several videos that walk you thru overhaul and tuning these simple carbs. There are also some mantis specific maintenance and troubleshooting videos that might help you...

Good Luck

 

[2manyrocks]

The good news it is a Mantis and so it's probably a common carb and not some mystery carb from places unknown.

 

[Jim Thompson]

The good news it is a Mantis and so it's probably a common carb and not some mystery carb from places unknown.

Zama C1U is a very common carburetor and pretty easy to service. Same carb that a lot of Echo equipment uses. I used to buy the fuel pump diaphragm and metering diaphragm by the ten pack. Most of the time you don't have to remove the clean out plugs, but if you do, be sure to reseal them. I use clear fingernail polish.
I would suggest going the the Zama web site and click on the technical section for lots of good info.

Jim