Jump to content

Nominations for Tractor of the Month
Garden Tractors and Parts on eBay



Photo
- - - - -

Briggs part help please


  • Please log in to reply
5 replies to this topic

#1 mjay OFFLINE  

mjay

    Member

  • Member
  • Member No: 1209
  • 6 Thanks
  • 65 posts

Posted May 16, 2011 - 01:06 PM

I have replaced a metal fuel pump on a briggs engine with a new plastic one.

With the plastic pump came a note saying I needed to order vaccum hose part no 694000 (goes from rocker cover onto the fuel pump).

Does anyone know if this is anything special? Does it have a restrictor in it or anything?

The engine is overfuelling badly and I wonder if it could be because the new pump is supplying too much fuel and forcing it through the carb.

It is a Briggs Vanguard V twin vertical.
Initially fuel was pooling up at the back of the carb in the inlet manifold, and then eventually running to the front and out the air filter.
I replaced the float valve, and I changed the float height so it shut off sooner. The fuel pump was corroded inside so I replaced it anyway. This seemed to make it work well, so I sent it back, but a week later it was back with this backfiring etc again.

Symptoms are that it is intermittently backfiring through the carb, and occasionally pushing out a huge cloud of black smoke. This happens every few seconds or so, inbetween it runs fine.
I'm not the first person to be fiddling with this engine, so I dont really know what has been done before me.

I'm wondering if there is an ignition problem? Plugs are black on both sides as you would expect.
The carb isnt adjustable so no luck there.

#2 NUTNDUN OFFLINE  

NUTNDUN

    Lost in Cyber Space

  • Admin
  • Staff
  • -GTt Supporter-
  • Contributor
  • Member No: 3
  • 10,266 Thanks
  • 15,618 posts
  • Location: Pennsylvania

Posted May 16, 2011 - 01:40 PM

Have you checked the valve clearances? They are pretty easy to check on the Vanguards since they are right there on the side. We have a Huskee lawn tractor with a 22hp Vanguard. Our problem was it was missing alot and backfiring. I checked the valve clearances and sure enough one of the push rods had fallen out of place. I put it back together and within another week the other cylinder dropped the push rod, only this time it bent. Briggs used aluminum push rods on the intake side for some reason and they are easily bent. The good thing is though the push rods for the exhaust valves are the same and I replaced both of the aluminum intake pushrods with the steel ones.

Ours started popping and carrying on again and here the clearances loosened up some more, I readjusted the valves again and all has been good. Might be something to check.

#3 NUTNDUN OFFLINE  

NUTNDUN

    Lost in Cyber Space

  • Admin
  • Staff
  • -GTt Supporter-
  • Contributor
  • Member No: 3
  • 10,266 Thanks
  • 15,618 posts
  • Location: Pennsylvania

Posted May 16, 2011 - 01:42 PM

I should also add that if you are careful removing the valve covers you will be able to reuse the gaskets provided they are not dried out.

As for the vacuum tube, I don't know if they would have a restrictor in the line or not since they call for a specific part number to be used. It kind of sounds like you might have an intake valve that isn't working, whether it is because of a bent pushrod or one that dropped out or some other reason.

#4 olcowhand ONLINE  

olcowhand

    Red Tractor Nut & Diesel Addict

  • Staff Admin
  • Staff
  • -GTt Supporter-
  • Sponsor
  • Contributor
  • Member No: 20
  • 35,568 Thanks
  • 29,820 posts
  • Location: South Central Kentucky

Posted May 16, 2011 - 02:58 PM

Jim, that part lists for less than $2, so I doubt it's anything special.

#5 mjay OFFLINE  

mjay

    Member

  • Member
  • Member No: 1209
  • 6 Thanks
  • 65 posts

Posted May 18, 2011 - 01:25 AM

Are the clearances 10 and 14 on this engine?

#6 olcowhand ONLINE  

olcowhand

    Red Tractor Nut & Diesel Addict

  • Staff Admin
  • Staff
  • -GTt Supporter-
  • Sponsor
  • Contributor
  • Member No: 20
  • 35,568 Thanks
  • 29,820 posts
  • Location: South Central Kentucky

Posted May 18, 2011 - 04:28 PM

As I see on the online chart, all the vanguard twins are .004 to .006" on both intake & exhaust. Briggs and Stratton Valve Clearances




Top