Lawnflite belt replacement

[RobWilsher]

I am trying to replace the motion drive belt on my ageing & trusted MTD/Lawnflite sit on tractor mower model no. 133 528 611 C213A

I am not sure how it fits around the engine drive pulley - there is a protection plate with 2 flanges. I think that on 1 side the belt goes inside the flange and on the other side, outside the flange. If I get it wrong, I am sure the belt will be damaged.

The picture in my manual (photocopied) is not clear.

HELP!!

Thanks, Rob

[richard p]

my lawnflite is chain drive to the rear axle, so im only generalising, usually the bracket arround the pulley is there to keep the loose belt in the groove when its slackened by pushing down the clutch pedal. so i would expect both metal bits to be outside the belt and not in contact with the belt when its tight.... the belt should only touch rotating pullies when its tight

hope this helps.. someone else who actually knows what they're talking about may be along later.

[RobWilsher]

Thanks Richard.
My machine also has a chain drive from the gearbox output to the rear axle. You are absolutely right about the belt tightening up when the clutch is released. On release it appears that the belt would be better aligned with the engine drive pulley outside the flange but I used to think that the metal protection plate was to ensure the belt stayed on the pulley wheel!

What model have you got?

Cheers
Rob

[richard p]

think its an 11/26 or something like that, 11hp b&s engine with a 26 inch cutting deck , rear discharge, got a grey bonnet . ill try and grovel under this afternoon to see if theres a belt between the engine and gearbox,... if there is it hasnt broken yet .

[RobWilsher]

It seems Richard that you have a similar machine to mine-I have a photocopied manual that I can copy for you if any use.

I have recently redrilled and tapped the exhaust box bolt threads and also the ones for the starting motor.

Have just totally overhauled the electrics and got the "headlights" working again-(nothing like mowing at midnight!)

I also have an older one that I use as a donor for parts that I cannot get easily. The engine mounting rubbers have been replaced several times-again very expensive but I now make them by splitting some rubber tubing of the right size!
I can get a 62" drive belt for a fiver, locally.
Cheers, Rob

[richard p]

ive had a look under mine , there is a drive belt from the engine to gear box, above the one to the cutting deck. the top crankshaft pulley is half surrounded (front half) by what apears to be part of the chassis (or a lump of metal bolted to it) there is an idler pulley directly behind the the crankshaft pulleyon the outside of the belt so it wraps the belt arround the crankshaft pulley so it drives on about 3/4 of the circumferance of the crankshaft pulley, theres a seperate tensioner/clutch pulley as well.
ill see if i can get a pic tomorrow evening.

[RobWilsher]

Great success!
Belt replaced and machine working well
EXCEPT?

A wiring wierdness

The engine will only start with the headlamps switched on and the other strange thing is the lights don't stay on they just flicker occasionally. Once the engine is going the lightswitch can be turned off and it keeps going!

It must help the solenoid to work the starter motor is what I guess but I can't understand why-does anybody?

[richard p]

the wirings wrong somewhere, may be easier to run a new wire from the start switch via the cluch safety switch to the solenoid and then rewire the headlights than trying to trace the fault on the existing wiring.

[RobWilsher]

Thanks Richard

I think you're right.
Funny thing is I checked every safety switch (opened them up, cleaned and lubricated them with Maplin's special juices) checked all the cables for continuity with a multi meter and was sure that all would be well when the major service was over.

From the manual that I have got it appears that the feed for the headlights comes straight from the alternator (under the fan) and via a switch to the lights and then the metal body completes the circuit. That is exactly how it is on my machine but some how it affects and assists the starting circuit.

There is another lead that goes into the engine on the other side (carb side)and I'm not exactly sure what it is for and I think I need to check that one out aswell - do you know when these machines were made? Mine sounds similar to yours - its a 5 speed 10 HP 26" cut with B&S engine with MTD/Lawnflite on each side of the bonnet. Spares are tricky to get and extortionately priced too.

I'm also trying to find out whether there should be a gasket between the exhaust silencer and the exhaust port ( a very hot spot!)- mine doesn't have one and I have to retighten the exhaust bolts regularly from vibration even with the knock over tabs in place.

Cheers

rob

[oldherbaceous]

Dear Rob, i was wondering if it could be an earth fault, this often causes weird problems.

Alright Clive, you can get back on the chair you have just fell off.

[Clive.]

I'm hiding under my chair Old H'....keeping out the way.. ....cos I know nothing about ride on electrics..and especially nothing about MTD/Lawnflite brand.. ..

..however some idea of age of machine can be determined from age of engine, if original,...usual B&S Model, Type Code numbers stamped into engine tinwork..with Code reading Year, Month, Day, Factory.

..also I have a feeling that on some B&S engines on ride on types they had seperate alternator coils under the flywheel...one to feed rectified for battery charge and another for AC lighting power.??..to give lights with engine on without drawing down battery or affecting battery charge input...

So unfortunately..other than a few musings..I know nothing.!!

Edit...to add...with those B&S engines numbers found..a few more answers...ref gasket..and perhaps even wiring can be found using numbers via this link; http://www2.briggsandstratton.com/maint ... _and_more/

I seem to think some exhaust boxes may not have had a gasket others an aluminium plate that perhaps gave some shielding...??

...and another edit. ...thinking on, a proportion of B&S engines have/had the facility to fit a threaded pipe with lock ring type of exhaust instead of a bolt on exhaust box. If threaded as such it would give a further option if the bolt mounting threads go terminally poorly..

Clive.

[RobWilsher]

Thanks Clive,

seems like you know a hell of a lot!

You are correct about the electical generator under the flywheel-one output through a diode for charging battery and one output for the lights.
It appears that this machine was made circa 1983 and I just like keeping things going if I can.

I really can't be bothered about the lights but I am determined to discover why the starter motor will only turn over when the lighting circuit is switched on

Cheers

Rob

[vancrasher]

Hi Rob, sorry to but in and I know its now 2013, however I too have a lawnflite its 906 and model no/ 13AO765N611 and I am in desperate ned on a mower deck pan (item no/ 683-0081B) and they are obsolete!! do you know where I might be able to get one.
Jimmy
Anglesey