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Ot: Briggs engine run without oil
tegwin - 18/9/15 at 10:53 AM

My grandmother has a ride on tractor with a 15hp Briggs and Stratton engine in it. The gardener chap who uses it to mow her lawns is a monumental buffoon and hadn't checked the oil for months meaning the inevitable happened and it stopped working....


The engine still seems to turn over so isn't seized... I've not pulled it apart yet.

Does anyone know much about these engines? Can they be sufficiently disassembled to allow them to be repaired and recover from no oil?

It's had a pretty hard life as the garden is steep and the aformentioned gardener has no mechanical sympathy Atall.


Recon it's worth taking it apart to repair or is it likeley to be FUBAR inside?


cloudy - 18/9/15 at 11:24 AM

Normally the conrod snaps first when these run out/low of oil. Had the same with my B&S - if the engine turns over faster than usual it's probably that. £25 odd for a pattern conrod and you'll probably be fine if the journals survived

James


tegwin - 18/9/15 at 11:27 AM

That would be nice if it is just a conrod.... If the journals are scored I guess they can't easily be reground? Only way to find out is to take it apart I guess...


cloudy - 18/9/15 at 11:41 AM

Pretty repairable, plenty of parts available so yeah I'd split the casings and take a peek...


Mr Whippy - 18/9/15 at 11:53 AM

tbh this has happened a few times as my dad is just as good at checking his lawn tractor and it has more than once ran out and stopped. All I have done after filling it with oil is take the plug out, squirt oil into the cylinder and thumped the piston back down with an socket extension bar! sounds brutal but nothing has broken and the performance is just the same afterwards. They're really quite robust engines and can take huge abuse. Main bearings are usually ball so not so prone to damage with low oil.

The weak points on lawn tractors are the gearboxes and they need good grease and the tractor stopped before selecting gears. Starter motors also tend to be lots of fun.


HowardB - 18/9/15 at 12:45 PM

mine seems to run with and without oil, it either burns it or it leaks out,. I try to remember to refill it, but sometimes I forget,......

oh well, it was free and as above seems to thrive on abuse


Staple balls - 18/9/15 at 01:06 PM

We've got a few things with smallish briggs engines in em.

Cannot. Frigging. Kill. Them.

I've got a lawnmower that runs on stale petrol and whatever oil dregs I have about (mainly because it gets through a lot of it) I think it's on mobil 1 atm, last time it was classic sh!tbox 20-50.


Also have a rotorvator that'd been salvaged for parts, Banged a sparkplug in there, filled the float bowl with 2 stroke (I was out of clean petrol), pulled the string. Puked a load of oil/water emulsion out the exhaust, started running on the 4th pull. No idea how it looks internally, but it goes.


Saying all that, I seem to remember some of the bigger briggs engines have horrible things like plastic camshafts, which could be entertaining at some level.

[Edited on 18/9/15 by Staple balls]


britishtrident - 18/9/15 at 01:54 PM

If it is turning over and you can feel compression check for a spark and condition of spark plug , having written that my money would be on the carb and fuel tank needing cleaned. The carbs on B&S engines have an internal fuel filter that gets choked up with grass dust and paint flakes from the tank.

[Edited on 18/9/15 by britishtrident]


Irony - 18/9/15 at 06:18 PM

I think they are mostly designed to run without much oil. My missus has tried to kill mine several times.


lsdweb - 18/9/15 at 09:17 PM

Our Husqvarna (b&s) ride on snapped a rod ( light load and pretty well maintained) . It was carnage! Whole bottom end was scrap. 450 quid for a bare bottom end and hours to strip and rebuild. It does sound really sweet now though!

Wyn


Doctor Derek Doctors - 18/9/15 at 09:37 PM

I think.I must be the only person who.has ever managed to kill one by the sounds of it! I ran my Briggs engined lawn mower out of oil, refilled it but a few weeks later the conrod came flying out of the casing!


coozer - 19/9/15 at 07:05 PM

Ive took the balancer thing off my lawnmower and replaced the springs with bits of hard wire so I can rev it like my bikes

Cuts wet grass in a jiffy, lets see how the long the thing lasts!


Brian R - 19/9/15 at 11:32 PM

Some Briggs have a low oil level sensor that cuts the ignition and stops the engine to save it. It could just be that.
Tip some oil in it and try it.