How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Curtis B. Your Own Question
Curtis B.
Curtis B., Technician
Category: Small Engine
Satisfied Customers: 28119
Experience:  Service manager and technician for all brands of engines with 40 + years of experience.
30244710
Type Your Small Engine Question Here...
Curtis B. is online now

Mountfield 1740h engine runs normally but when elecromagnetic

Resolved Question:

Mountfield 1740h engine runs normally but when elecromagnetic clutch is engaged engine backfires and shears the flywheel key
Submitted: 1 year ago.
Category: Small Engine
Expert:  Curtis B. replied 1 year ago.
With engine off, can you turn the electric clutch pulley and the deck assembly? The clutch may be locked and is locking up the engine on engagement. ???
Customer: replied 1 year ago.

Dear Sir,

The cutter blades on the deck moves freely and the Clutch moves freely and the micro switch works.

When I depress the "clutch Switch" it immediately backfires and shearers the key

Customer: replied 1 year ago.

Dear Sir,

The cutter blades on the deck moves freely and the Clutch moves freely and the micro switch works.

When I depress the "clutch Switch" it immediately backfires and shearers the key

Expert:  Curtis B. replied 1 year ago.
Unplug the wires from the electric clutch, then turn on switch to see if it does the same. What are you torquing the flywheel bolt to? What is engine model number?
Customer: replied 1 year ago.

.

Briggs and Stratton 1740H

Model : 31G777

Type : 0120E1

Code : 021213ZE

Torque : 60 Ft. Pds

After 10 sheared woodruff keys flywheel has cracked.

Waiting for new flywheel to be delivered from USA

Unable to run test at present

Expert:  Curtis B. replied 1 year ago.
http://outdoorpowerinfo.com/engine_specs/briggs_fly_torque.asp
Expert:  Curtis B. replied 1 year ago.
Torque looks to be 100 ftlbs
Expert:  Curtis B. replied 1 year ago.
How did this all begin?
Customer: replied 1 year ago.

Cutter blades struck a mole hill and sheared the flywheel Key

After many attempts "9" in total ran out of shear pins and a cracked

Flywheel.

Without energising the Clutch the engine would start on the key and run sweetly .On pressing the Clutch switch, Very loud backfire and sheared flywheel key.

On examination each time clutch was not seized and blades free.

Could it be carburation and or governor

I will have to put you on hold until I receive the flywheel before I can run your latest test

Yours Aye,

Jim

Expert:  Curtis B. replied 1 year ago.
I think the problem is you are not putting enough torque on the flywheel bolt/nut, shows to be 100 FT. LBS.!
Expert:  Curtis B. replied 1 year ago.
Key shears as soon as load is put on engine, then it backfires!
Curtis B. and other Small Engine Specialists are ready to help you

Related Small Engine Questions