Mountfield R28M ride on Mower not starting (Again!!)

WIAWSNB

Yes but...yes but... we didn't actually do anything here

Fingers crossed, but if it reverts to previous behaviour, I think assume a poor connection somewhere.

Section62

sujsuj said:

Thanks so much to everyone here for the support. Every time I hit a challenge, you all come through with advice and encouragement. You helped me get through it again this time!

I hate to be the bank holiday raincloud on your moment of triumph, but that engine is running rougher than a badger's bottom.  You've got something fundamentally wrong with it if it will only start in the circumstances described, and it makes that noise when running.

Same advice as before, you've done about all you can on a DIY basis, it really needs looking over by a professional who could give it a mid-life overhaul and keep it running for years to come.  Saving the cost of that overhaul may well cost you a new lawnmower much sooner than necessary, which would be a real shame.

sujsuj said:

The only major change I made was keeping the battery on charge for over 48 hours. Before starting (same as yesterday), I pushed the pinion back to its lower position. I also manually rotated the blades — every 4–5 turns it would get stiff (due to shaft?), so I made sure the engine is in the sequence where it rotate easily  before ignition.

Your mower has a clutch between the engine and blades - so where the blades are positioned should make zero difference to how easily the engine starts.  If the blades are turning when you try to start the engine then it suggests you've left the clutch in, or else the clutch isn't releasing properly (perhaps due to misadjustment).  Starting the engine with the blades engaged will damage the engine.

The blades should rotate freely and not 'get stiff'.  Which suggests maybe the clutch isn't disengaged and the 'stiffness' is due to you reaching the compression (/power) stroke of the engine?  If the stiffness is due to the mower deck rather than the engine then it would point to a bearing failure*, which again is something you need to deal with ASAP. (* I don't think your mower has a blade brake, but if it does then it could be that instead)

Hopefully you removed the spark plug lead and grounded it before manually rotating the blades?  If the clutch isn't working properly and the engine is turning the blades all the time then the reverse is probably true - that rotating the blades will rotate the engine.  If the spark plug lead isn't disconnected and grounded then there is a risk of the engine firing (starting) which would lead to anything near the blades being sliced like salami.

But the early videos you posted showed that the starter pinion wasn't moving to engage the ring gear on the flywheel.  That fault has nothing to do with the blades (or clutch), and as you eliminated a faulty battery by jumpstarting from your car it means either the starter motor is faulty, or else there's  wiring problem as has been pointed out a few times.

WIAWSNB

I thought it ran quite sweetly! But possibly a bit of exhaust blow?

Totally agree - SS, get it fully checked over and serviced, if you want it to last.

greyteam1959

I don't think an engine running as rough as that it's going to cut any grass at all !!

sujsuj

I know many of you mentioned the sound of the mower in the video I shared yesterday. In fact, when I managed to start it yesterday, I was so excited that I forgot to move the lever away from the starter position. That’s why it sounded like that. I moved back to normal ride position soon after that video ended.

I’ll post another video tomorrow with the normal sound—this time with the lever in the correct position.

Apologies for the confusion, and thanks for pointing it out!

sujsuj

greyteam1959 said:

I don't think an engine running as rough as that it's going to cut any grass at all !!

Section62 said:

sujsuj said:

Thanks so much to everyone here for the support. Every time I hit a challenge, you all come through with advice and encouragement. You helped me get through it again this time!

I hate to be the bank holiday raincloud on your moment of triumph, but that engine is running rougher than a badger's bottom.  You've got something fundamentally wrong with it if it will only start in the circumstances described, and it makes that noise when running.

I explained it in my post earlier today that video was when teh level was in starter position

Same advice as before, you've done about all you can on a DIY basis, it really needs looking over by a professional who could give it a mid-life overhaul and keep it running for years to come.  Saving the cost of that overhaul may well cost you a new lawnmower much sooner than necessary, which would be a real shame.

Sure Thanks

sujsuj said:

The only major change I made was keeping the battery on charge for over 48 hours. Before starting (same as yesterday), I pushed the pinion back to its lower position. I also manually rotated the blades — every 4–5 turns it would get stiff (due to shaft?), so I made sure the engine is in the sequence where it rotate easily  before ignition.

Your mower has a clutch between the engine and blades - so where the blades are positioned should make zero difference to how easily the engine starts.  If the blades are turning when you try to start the engine then it suggests you've left the clutch in, or else the clutch isn't releasing properly (perhaps due to misadjustment).  Starting the engine with the blades engaged will damage the engine.

So while starting the engine should i engage clutch or not.?

The blades should rotate freely and not 'get stiff'.  Which suggests maybe the clutch isn't disengaged and the 'stiffness' is due to you reaching the compression (/power) stroke of the engine?  If the stiffness is due to the mower deck rather than the engine then it would point to a bearing failure*, which again is something you need to deal with ASAP. (* I don't think your mower has a blade brake, but if it does then it could be that instead)

Hopefully you removed the spark plug lead and grounded it before manually rotating the blades?  If the clutch isn't working properly and the engine is turning the blades all the time then the reverse is probably true - that rotating the blades will rotate the engine.  If the spark plug lead isn't disconnected and grounded then there is a risk of the engine firing (starting) which would lead to anything near the blades being sliced like salami.

Thanks for highlighting that danger

But the early videos you posted showed that the starter pinion wasn't moving to engage the ring gear on the flywheel.  That fault has nothing to do with the blades (or clutch), and as you eliminated a faulty battery by jumpstarting from your car it means either the starter motor is faulty, or else there's  wiring problem as has been pointed out a few times.

I planned to do a service soon, problem is I may have to take it to a store as Mower mobile services are rare I think. But i will have a look. thanks

sujsuj

I bought these battery from Amazon and Mower is working normal. Thanks very much everyone.

Lawnmower Battery Ultramax 12V 20Ah - (Replaces F19-12B)       

https://www.amazon.co.uk/dp/B00TPOWDNE?ref=ppx_yo2ov_dt_b_fed_asin_title