Vanguard 18hp won't start after maintenance

[srfnson]

Ok could use a little help on this guys....

I have been working on my 2004 bigfoot this winter changing chains, doing body work, and engine maintenance. Argo was running fine a few months ago before I drained gas out of it. Been sitting outside (covered) in very cold temps with battery maintainer on it.

Changed fuel filter, plugs, battery, throttle cable, oil, and installed new winch, bilge, accessory plug and digital battery meter tapping into existing electrical. All electrical devices work fine now.

Fresh gas in the tank, engine turns over but doesn't start or sound like it's getting spark. Tried started fluid but no effect. Checked spark and either not getting spark or getting weak orange spark in tester. Put old plugs in and no difference. New battery looks fully charged.

Also noticed new fuel filter (installed correctly) is hardly filling up with any gas. Ensured gas line was not pinched and gas was getting to filter. Pulled line off pump that goes to carb and tried starter and fuel squirts out but filter still seems to have barely any fuel in it. Took filter out and connected lines together and tried it but no go.

Checked ground wire to engine with multimeter and getting good ground. Also checked gas tank vent line and it is unobstructed.

So seems to me I have both a fuel delivery and electrical (spark) issue. Will change fuel line and pump tonight and clean out carb but doubt that's my issue. I'm stumped as it was running so well before I drained fuel and added various electrical accessories.

Any suggestions would be greatly appreciated....

[hydromike]

Also noticed new fuel filter (installed correctly) is hardly filling up with any gas.

Hey srfnson,

Many filters won't "fill up" with gas, even though they're transmitting plenty of fuel. It's tough for gas to drive the air out when the filters are laying on their side. I'm going to bet (and especially since you eliminated the filter once and it still wouldn't fire...) that it's not the problem.

If you can't **SEE** a spark at both plugs, and you can't get the pig to fire on ether, I'm going to lean towards a purely ignition-related problem. Are you getting bad spark at BOTH plugs? The Vanguards have a wire with a diode in it that connects the coils, and can lead to one cylinder not firing when it goes bad. I'm not going to bet on this either though. Ether and even a small spark usually gets some result.

It looks like you did quite bit of electrical work on it during the maintenance season. Can you eliminate the majority of the electrical going to the engine (including the key switch) to see if you can get it to fire? Try it as a stand-alone engine and work forwards from that, perhaps.

[CBass]

I had some issues on my last Busco ride back last April when my had been running strong all day then it just wouldnt start when I got back to camp. I even replaced the wire with the diode and still nothing. I check my spark plugs and even replaced them. We tossed around idea after idea. We check the spark plugs again and found that it was going in too deep and had got hit by the top of the piston so I and a crush washer that was on the old plugs, still nothing but solved that problem with the spark plug. It all came down to valve adjustment. I google how to do one and using a thickness gage we adjusted my valves. It cranked right up! Not saying that is the case here but it might be worth a check just to see.

[Mike]

I think that hydromike is probably right about it being an electrical issue but you can always remove the air cleaner and spray some starting fluid directly in the carburetor. That will quickly help you eliminate fuel being an issue if it doesn't start.

[eddieb1965]

I dont use any starting fluid ever,if it is a fuel related problem,you can give it a shot of gas with a oil can with a pistol grip.If it were to start with the starting fluid it offers little to no lubricating propertys no matter what it says on the can.

[srfnson]

Thanks guys!

Hydromike nailed it...definitely electrical.

Here's the situation...

I removed the winch and accessory connections from the battery and still couldn't get it to fire up. Then I was fiddling with the key and discovered if I turn the key to the start position to activate the starter motor and then quickly turn the key to the off position she fires and runs fine with the key in the off position. I figure I must have tapped off the wrong power wires coming off the ignition switch when I installed the digital voltage meter.

When I hooked up all the battery cables I'd disconnected this trick with the ignition key doesn't work.

So heading out this morning to first remove the digital voltmeter connection and see if that fixes it. If not perhaps it's the winch switch wire that's tapped into the ignition switch.

Will have to study the wiring schematic to see if I can figure out the proper + wire to tap off of on the ignition switch.

While I'm at it going to check the valves as well so thanks for that suggestion too.

Thanks again for everyone's suggestions and help!

Paul