Jump to content
The Gman

418 long in the tooth to start

Recommended Posts

The Gman

Starting to scratch my head on this one. Getting my 418 serviced and ready for snow duty for my daughter to use at the farm but after sitting for three days at a time it takes a good 10 to 15 sec. of cranking to start with full choke. It's still 18 - 20C up in my neck of the woods so I can just imagine at 10 - 15 below in Jan.

All the others in the herd are starting to giggle at it.

 

Bought it in late spring this year and ran it through its paces back then no problems. Sat in the horse house for three months. Cold start took about 10 sec. first time out but started like a champ each time after that. Seems to be after a two or three day sit it takes too much crank time to start.

Here's what I've done to date:

- Change the fuel filter.

- Checked the output of the pump, good flow, squirts at me when I thumb it off to check pressure.

- Placed a napkin under the fuel bowel to see if there is a leak. Nope.... clean after a day.

- checked choke plate for full closure. Hard too see but looks good.

- Checked the carb to intake, intake to cylinder bolts. All tight. Even put a little vacuum grease around the gasket areas just in case.

 

When i take the air filter/housing off and palm (hand) the the intake it springs to life. No 15 sec. wait. It's a walboro fix jet cab from the looks of it. Noticed yesterday that when its running and i pull the choke on. It only makes a 5 - 10% dip in engine performance.  If I need to pull the carb I will but looking for some ideas of what to look for.

 

Air leaking by the throttle or choke shaft?

Choke plate???????

Gas siphon back out of the carb thru the pump?

 

I'm starting to wear a quarter sized bare spot on my head.

B)

 

20180921_110827.jpg

20180921_110752.jpg

Share this post


Link to post
Share on other sites
 
pfrederi

My 418 took forever cranking to fire up after it sat for a few days.  Electric fuel pump completely solved that issue...now if I could just make the hydro lift work immediately....

  • Like 3
  • Haha 1

Share this post


Link to post
Share on other sites
 
WHX??

All my Onan's like that G .... only thing that will get them fired  up after a set is s fluid. I'm with Paul on the pump but have not done it ....Yet. I'm thinkin gas siphons back to the tank.

  • Like 2

Share this post


Link to post
Share on other sites
 
953 nut

Your fuel pump is on the top of the engine and the fuel tank is under the seat, takes a lot of suction to lift the fuel up to the pump. Once the check valves in the pump begin to weaken and the fuel drains back to the tank the situation worsens.

Like Paul, I replaced the mechanical pump with an electric pump mounted low enough that the fuel line is above it and now it starts up immediately.

 

  • Like 1

Share this post


Link to post
Share on other sites
 
pfrederi

I have to admit his is odd  all my twin under seat tank tractors were terrible about cranking forever (as was my C141...but for reasons unknown to me the 310-8 with a K241 fires up almost instantly Go figure

Share this post


Link to post
Share on other sites
 
WHX??

I have a better solution G.... fire it up every day and get yourself some seat time! :lol:

  • Like 1
  • Haha 2

Share this post


Link to post
Share on other sites
 
gwest_ca

A closed choke increases the vacuum in the carb but the throttle plate needs to be open a bit for the choke to be effective. That is built in in auto carbs but not the small engine carbs unless they have an automatic choke and few do any more.

I found multiple short cranking periods more effective than continually cranking.

 

Garry

  • Like 3
  • Excellent 1

Share this post


Link to post
Share on other sites
 
buckrancher

simple solution is to put a primer bulb like the kind that comes on a portable outboard boat motor fuel tank

inline near the engine a couple of squeeze's by hand and your good too go

 

Brian

  • Like 3

Share this post


Link to post
Share on other sites
 
The Gman

Thanks for the input guys..... gave me some ideas to check out and thought of a few more things to look at. Will let you know.

 

More seat time is always at the top.

Edited by The Gman
  • Like 1
  • Excellent 1

Share this post


Link to post
Share on other sites
 

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...