Just need it clarified... 3.5hp B+S

LILACSPLASH · « **on:** February 26, 2008, 23:30 »

Ok, this one might be specifically to GWIZ (or other knowhows!) I might sound dim, and maybe I am but.... can it run out of petrol, get some more and work fine, switch it off, bring it out a day later and not start 'cos the petrol level is too low? thinking here of the two pipes (in the tank) and one being longer than the other - if this makes sense?...
Ness

jack russell · « **Reply #1 on:** February 27, 2008, 00:12 »

Hi Ness first thoughts are that if the petrol is low to the point where you are concerned then top it up. I would think you are on the right track with your thoughts about the uptake pipe thingy

but i may be wrong, I have been before

Have you tried it with more fuel :?:

LILACSPLASH · « **Reply #2 on:** February 27, 2008, 00:23 »

it went well lower when it ran out, only a puddle left, but then when your happliy rotovating with the up + down of the land... so put more in + give it a go. Has half a tank now and still wont start. As the only female that does mechanical i'll have to put more petrol in covertly to avoid the inevitable red face.
P.S have to get the beasty running soon as i've promised the primary school i'll get there lotty garden up + running this spring :? :shock:

LILACSPLASH · « **Reply #3 on:** February 27, 2008, 00:31 »

Cant be the gap tween flywheel + magneto done that + up tight, but could be the plastic thingy that clips in (condenser?

) done the 1.5 turns on the carb screw/ still wont run :x ran for half a tank after, so not bunged up, perhaps i'll go back to a girlie thing + i worked it too hard last time!!!

Gwiz · « **Reply #4 on:** February 27, 2008, 05:52 »

Sorry for the delay, I'm an early to work person, so I have to "turn in" early to bed!
The answer to your question is yes. With the Briggs engine ( fuel tank fitted to bottom of carb model) The engine relys on its induction stroke vacumm to pull up the petrol from the tank. This is aided to a degree by a very small gasket in the body of the carb.
As the machine gets a bit older, a couple of things tend to happen, firstly the filters that are on the ends of the tubes in the tank become a little blocked, so the amount of petrol "sucked" is lower, and secondly, the compression in the engine becomes a little less, so there isn't so much "suck" in the first place.
It is possable to increase the compression with new piston rings and whatnot, but I find it's much easier to sort out the problem of the blocked filters by removing the tank and stripping and cleaning it all.
A short term fix is to try starting the engine with the fuel tank never less than 3/4 full.
all the best, let me know how you get on.

As an after thought, you have got a spark, haven't you? if you haven't allready checked, put the throttle lever into the run position, remove spark plug, rest it on the top of the engine, attached to the plug lead, and give the rope a good pull. you should get quite a good visable blue spark, if not, you might need to start delveing into the ignition side of things a bit more....
I thought i had better ask, you never know......I've done it myself, spent AGES fixing one problem, for it to turn out to be another....DOH! :roll:

LILACSPLASH · « **Reply #5 on:** February 27, 2008, 13:50 »

Cheers, I think I might just be getting the hang of this engine lark :o
It's nice for someone to understand what I'm trying to explain and how I got to thinking which bit wasn't working right, I generally get the Roger Moore look followed by sniggering!
Anyway, I think I'll opt for the 3/4's of a tank approach until that doesn't work anymore, then a strip down.
I did try to get the cover off the diaphram before but it was on really tight and I didn't want to muller it, so left it. But if it has to come off I'll show no mercy :twisted:

Gwiz · « **Reply #6 on:** February 27, 2008, 17:10 »

yeah it can be a tadge tight. Undo the screws and give it a tap downwards with a small hammer to loosen.
if you're gonna have to strip and clean the filters, best left till then!!
Have you tried the "more petrol method" yet?

If you lived closer, I'd give you an interveiw for our apprentice mechanic vacancy!!
we've been advertising within the company, and outside of it, and we've only had two people apply, one of thems a girly of 18. I've got to say, she's our prefered candidate at the moment because she is keen, and knows what a spanner is!!! ( unlike the other one who thinks it's gonna be a skive ) :twisted:

Bigbadfrankie · « **Reply #7 on:** February 28, 2008, 12:26 »

which town in sunny cornwall or which school ?

LILACSPLASH · « **Reply #8 on:** March 19, 2008, 21:47 »

Guess what it was after all this... :roll: was the idle speed screw vibrated on to, too slow to go. The spring must have lost it's springyness, still never mind I'll get another one from room 101 (the cupboard under the stairs!)
Many thanks to everyone,
Ness
frankie - I live at the crossroads (calweton)...

Just need it clarified... 3.5hp B+S

Gwiz

Gwiz