5e gas smell solved

Liberty44140

first off I’m well aware that any gas smell is bad so I’ve been chasing this for a bit. When I shut down my genny I’d smell gas in the cabin. Running blower after shut down helped but that’s a band aid. I changed filters, looked over fuel lines, rebuilt carb, new choke, tried several things to stop it. Last summer I ran it and then shut it down while in the engine room to see if I could see a fuel leak or smell. Nothing found. Keep in mind that the cabin gas smell was sporadic, sometimes worse than others. This winter I read a blog on how holding down the stop button too long when shutting it down could be priming and kind of flooding it causing the smell. When I shut down historically I hold the stop button until it’s completely off. So, this year when I shut down I hold the button for just a half second at most. I just press stop quickly and that’s it. Gas smell gone! I was flooding it or something...

Black_Diamond

The anti-diesel valve should be closing off the fuel flow at shut down. 

Interesting solution!  Glad it worked. 

reneechris14

Never got a smell but will do this now. Admiral has a nose that can pick up a smell.

Liberty44140

Black_Diamond said:

The anti-diesel valve should be closing off the fuel flow at shut down. 

Interesting solution!  Glad it worked. 

Should have put that I changed the ads too. My theory is that fuel pump keeps running while your holding stop until it’s off but I don’t know where the fuel would go before the ads. 

Liberty44140

How long do you all typically hold down stop on the cabin button? Just a press of the button?

Black_Diamond

I hold the stop switch until the genny has stopped. Never had the gas smell with mine. 

Liberty44140

Interesting. I should note that this is only with the ac on thus pulling air and smells in to the cabin 

bella-vita

I hit stop for a sec than let it go it shuts itself off.

Dream_Inn

Liberty44140 said:

Interesting. I should note that this is only with the ac on thus pulling air and smells in to the cabin 

Are you saying that your AC is running when you power down the genny?  I've always ran my genny for 3-5 minutes under no load before shutting it off.  This allows proper cool down.

Liberty44140

Dream_Inn said:

Liberty44140 said:

Interesting. I should note that this is only with the ac on thus pulling air and smells in to the cabin 

Are you saying that your AC is running when you power down the genny?  I've always ran my genny for 3-5 minutes under no load before shutting it off.  This allows proper cool down.

Ac is running on shore power. Same as you I turn everything off, switch to shore power, and turn everything back on letting the genny run with no load for about 5 min. To cool. Definitely not stopping genny while it’s running the ac. 

PickleRick

In theory your anti after fire solenoid (anti diesel) should cut off any fuel entering the venturi of the carb.  

A couple things id check.  What kind of fuel pump does she have?  I just had a 1 yr old kohler 30 hp on a saw mill pushing 10 plus psi on a rocker arm driven fuel pump. Should only see 5 to 6 psi. This is common on mechanical fuel pumps even on a v8.

Next is the seat on both the fuel inlet needle and the solenoid.  When i rebuild them i polish the brass seating areas with a q tip and fine valve lapping compound.  Its important to be sure this is thoroughly cleaned out after.


Also equally important is to check the solenoid to be sure its opening and closing fully.  Honda twins will pull enough compression to run with a faulty solenoid in the off position, it's lean but runs.  

Liberty44140

I replaced the fuel pump summer 2016 with this pump. Was a drop in replacement but did come from a different site than the Koehler parts and was half the price. 

https://www.pegasusautoracing.com/productdetails.asp?RecID=7550

PickleRick

Ive had customers use the aftermarket ones in the past.  Ive so far only had one that put out too much pressure for the carb to hold.  A mr gasket inline fuel pressure gauge took care of it.  I just had my holly 4bbl rebuilt and installed a new Carter fuel pump for good measure and put an inline fuel pressure gauge/adjustable regulator for good back up.  

Usually my customers using these are setting up carpet cleaning vans where a propane hot water heater is just feet from the motor.  

A fuel pressure test kit is sub 40 bucks at harbor freight.