Honda 390 hard to pull start - ball valve is open

Machine Repairs
1

I have been having a growing issues with my first start of the day on my Honda 390. It simply will not let me pull the recoil without some messing around. I have my DN10 ball valve wide open at the end of my high pressure line so there is no issue there.

When I can finally finesse the recoil to pull it take about 6 or 7 pulls and the first 2-3 show a liquid shooting out of the muffler. I wonder if the cylinder is filling with gas and creating a hydro-lock. Heck, I even pulled the entire DS injector off the pump and it still was hard to pull.

I do pull from a buffer tank and the water is right up to the pump inlet.

Due to the liquid shooting out of the muffler I can’t help think the float bowl is stuck causing the machine to flood and somehow the gas is entering the cylinder. I can totally see this as being the issue.

Thoughts?

2

If you can confirm its gas coming out of the muffler then yes, the gas supply is trickling past the needle in the carb / fuel solenoid. Perhaps drop the fuel bowl, gasket, needle and carefully check the seat in the carb to ensure no trash/debris is there preventing a proper seal or cut-off of fuel.

For kicks, check the engine oil level. If it’s too high, drain it to proper level. If it’s too high the next day then you definitely have an issue as described above. Repair blockage, drain all engine oil, add new oil.

3

If you pull the carb off the machine and dissect it, be sure to not blow the small rubber seat out with an air compressor.

  • OR - you could intently try to shoot the small rubber seat out with an air compressor, but be sure to point it at someone who is wearing safety glasses. It is not advised to practice this technique on women or small children. Also, this may be known to cause cancer in the state of California.
4

Great advice, thanks! I really should have confirmed it’s gas shooting out the muffler. I’d wager with 95% certainty it is gas from a flooded cylinder. I will pull the carb like you said and look at the float and needle and needle seat.

Thanks again - it’s nice to finally be washing with my new setup!

1 Like
5

Do you by chance have this machine on a trailer? I bought mine in January of this year and it ran great. I reconfigured my trailer recently and the machine now sit towards the rear where it feels the rough roadway a little more than the front of the trailer. Mine has been hard to start taking near 5-10 pulls. I too had gas coming out the muffler, changed the spark plug and it still didn’t make a difference. I started to shut the gas off during transport and haven’t had anymore issues. Thought I would pass it along.

6

Hey thanks! I do have it on the rear of the trailer as well, very strange we have similar issues. I also thought to shut the fuel off at the last job so we’ll see how it starts next time. Thanks again!

7

Been happening to me too, but i have a fuel shutoff that i need to be using. When it happens I’ll pull the sp plug or drain the bowl.

8

I had to adjust the valves, actually got so hard to pull I broke a valve lifter ( it thinks thats what it is called) and had to replace it. Seems to be a common issue. Super simple to do and replacement parts were cheap and next day on amazon.

9

Yea, the more I thought about what Pwest21 said, the more I am convinced he is right. All float bowls have floats which rely on a level surface to maintain a certain float level. If my trailer is at a bit of an upward or downward angle it would cause the float to rise in order to fill with gas. The gas is so full it likely fills the cylinder too, hence the gas shooting out of the muffler when pulling the recoil.

Luckily I have a built-in fuel shut-off and will turn the gas off at the end of the job. When I was building my trailer I must have fired up the engine 15-20 times with no issue. The only thing that has changed is that it’s attached to my hitch and I am towing it around - both of these would perfectly explain my new issue.

Thanks!!!

1 Like
10

I bet i was on the way to this problem it seems…my last job my 390 ball valve open just wouldnt turn over , so i hit choke over like its warmed up and cranked up but i have been leaving my fuel switch on last few jobs i believe…i made to cut it off so well see how it goes
I had no gas or anything comijg out of muffler yet or hard to pull just only started once i flipped choke over so :person_shrugging: maybe flooded it a bit bouncing around :sweat_smile: