Hi All, Seen several threads along this line but nothing that seems to help me.
I have a Briggs & Stratton Model 303777 Vanguard (on a 1994 Snapper SR170 Rider).

The engine turns over well, but will not start. I am not getting any "thump" when it turns. I am not hearing any clicking from the solenoid (which some threads suggest I should be hearing).

The plugs are new and correctly gapped.
The battery is new.
The fuel line is new.
The fuel filter is new.
The fuel is new.
The carb seems to be clean.

I do not believe I have any "dead man" switches (there is nothing under the seat and I do not see anything in the operation manual about them).

At this point, I am stumped. It "feels" electrical, but I don't know where to go from there.
Any help would be appreciated!!

Have you checked compression? You do not need to invest in a tester on a OHV engine compression loss is more likley a valve train issue rather than wear, meaning either it is there or not. Do you feel any resistance on the compression stroke? If not you have issues.

Have you checked for spark, lots of threads discuss the methods.

If there is compression then to diagnose spark locate the coil grounding (kill) wire coming from under the fan housing and disconnect it from the terminal. This will isolate and eliminate the posibility of a dead mans switch. If still no spark then your ignition coil is bad.

This forum works well for diagnostics but when you say you have replaced those parts it would help if we know why and what was done in the way of diagnostics..
Good luck,
Don

Thanks, Don.

As to compression, yes, it has compression.

At this point, I am leaning towards the magneto armatures (with their integrated coils).

I popped the cowling off the top of the engine and both solid-state magnetos are badly corroded (the flywheel also had some corrosion, but I think it cleaned up OK).

I tried the dead man disconnect with no luck.

As to why I replaced everything I described in the first post, this was a "brother-in-law" special -- meaning he parked it in the back yard two years ago +/- and hasn't touched it since (and didn't cover / weatherproof it). The fuel hose was a little stiff, so I replaced it and the filter and spark plugs just for good measure (better to try the cheap things first, and then move up to the more expensive stuff).

I'm off to test for spark now, but I'm not holding out a lot of hope for those magnetos!

Thanks,

Rquick2

A magneto failure would cause loss of spark on one cylinder, It would still run but have no power. A twin is unlike an auto you do not experience a rough run just loss of power.

All riders come with safety switches, yours may have been disabled. Check spark on both sides, if no spark on either side probably a switch SOMEWHERE< isolate the coils.

Don