Briggs mower won't start

[38racing]

Friend's 103m020003f1 ser 16...... [103M02-0003-F1] on an MTD self propelled. pretty new unit. will only start and then stop on a shot of carb cleaner. will continue to run only on continued carb cleaner. I had a neighbour's similar unit last year which I resolved by carb removal but my conclusion was maybe bad gas. If memory serves me I did a quick bowl drop on this current unit and carb is different than the other. it's the one with a 3 tower main jet. anything other than a bit of ethanol crap is likely the issue here?

[KE4AVB]

First stop using that starter fluid it is damaging to cylinder. Just use the fuel the engine is intended to run on.

Now there has been a couple service bulletins related to this carburetor design in reference One pertains main to 08P and 09P series but can also apply to the 103M as it is the same carb design. And the other one covers erratic operations. With this in mind it is highly possible you have a clogged jet assembly. Reference DSB1054 and DSB1060. Available for download or viewing in the Downloads under Briggs Advance Service info directory.

[38racing]

Not using starting fluid (ether), using choke/carb cleaner. Someone suggested a penetrating oil because of the oil in it but I haven't tried to see if it's flammable enough. donyboy3 on youtube recommended a quaker state product (quik lube?) because of the oil in it but I was never able to find it.

[38racing]

I forgot to note that this is a ready start system, no choke , no primer. How does briggs achieve the cold start?

[KE4AVB]

The ready start system does have a choke. It just thermal operated version. They have thermal valve on the muffler that opens the choke as the engine warms up. When the engine is cold a spring pulls the choke closed. These systems can give trouble if not let to warm up fully as the choke will opened too much for a quick restart.

To me carburetor cleaner is just as bad as starter fluid. I haven't had a can of either one in my shop in over 4 yrs now. If you want something with oil it that is flammable just use some 2 cycle fuel mix. Actually can run these engines on it through they can smoke because of the oil. I do this as it is easier thing for me to put my hands here in the shop.

[Luffydog]

Yes the little plastic $30 carb. When you take the bowl off there's the white piece that is removable in the bottom is a little ball that gets stuck I found that if u push that out clean and put it back in and only push the ball in to where it gets stuck usually fixes the issue.

[38racing]

Yes the little plastic $30 carb. When you take the bowl off there's the white piece that is removable in the bottom is a little ball that gets stuck I found that if u push that out clean and put it back in and only push the ball in to where it gets stuck usually fixes the issue.

thanks. I been trying to find a manual in the the download section that includes103m series. so far no luck. is it best to remove that jet from the carb on the bench or leave carb attached?

[Luffydog]

Remove it that way u can inspect it. Note the way the bowl is on can't hardly remember but it seems like something is coming to mind about the bowl and the way it goes on but do remember the little silver ball that it causes some issues in most I have seen the white part is replaceable. The whole carb is like 30.

[KE4AVB]

Briggs hasn't release at specifically covers the 103M or 104M so we basically on our own. Briggs has been lacking on the latest engines promising manual on the way but haven't delivered on any.

The nozzle/jet assembly is levered out with a flat blade screw driver. One thing of note those carburetors related to the fuel bowl that I found after customer did it. It is to not over tighten the retaining screw or they will strip out the plastic carburetor base. Definitely easier to work on the carburetor off the engine and on the bench.

Luffy if you remember after a couple pots of Joe let us know as these carburetor are just now showing in my shop and so far I only seen two of them in last 3 years.

[38racing]

Of course that $30 carb is close to $70 cdn with tax ($53 USD at today's exchange) for us canadians.