Vanguard 35 fuel issues

[gyrusabsurd]

Welcome back, and it's great to hear that your health is improving! We're glad to see you around again.

Regarding the Vanguard 613477-3048-G1 issue, it sounds like you've covered a fair amount of troubleshooting already. If the engine runs fine when gravity-fed from a test tank but there's no fuel pumping to the carb, it could be a challenge with the fuel pump or the connection to the intake.

Since you've tried multiple pumps, it might be worth double-checking the connections and ensuring there are no blockages in the fuel line. If the hose from the engine to the pump is fine, you might want to inspect the connection points for any potential issues.

Considering the engine ran for a few hours with the existing setup, there might be a specific point where the fuel delivery is being interrupted. If all else fails, installing an electric pump could be a viable option.

Feel free to keep us updated on your progress, and the community is here to offer further assistance. Wishing you smooth troubleshooting and successful resolution!

[BLES]

OK. Here goes. Tried all the suggestions. Nothing conclusive, but...
Running on gravity test tank with air filter re-installed (It was removed for access to carb and fittings) to see if it would produce more vacuum to pump, it started pumping fuel into a container! I switched pump line with gravity feed and it quit again.... it was low on fuel! There was a line in the tank which appeared to be fuel level, but it was actually lower. With more fuel, and air filter installed, it's running again!

So, very embarrassing for me. A couple of "rookie" mistakes, but also what appears to be a very weak system at best. I have another exact engine that a neighbor dropped off. Similar story. Low hours, runs terrible if at all. Maybe I'll learn something with it.

Thanks again, gentlemen.

[KE4AVB]

Making progress I see...

Still looking like you are going need bite the bullet and switch to a low pressure electric fuel pump system. I know it is going cost more but sometimes it is necessary.

[bluemower]

The new big block service manual is available on the power portal - not sure about this site. On page 60, there is a drawing of the fuel pump and the pulse connection to the intake manifold. I have had positive experiences with electric fuel pumps on equipment that is also equipped with the pulse pump. I installed with a fuse and push button. Instructed the operator to push the button for a few seconds prior to starting the engine. After the engine started, the pulse pump kept the engines going. This setup also worked well with riders that experienced vapor locking. Previously NAPA offered 4 psi pumps - don't know if these are still available.

[KE4AVB]

Actually there is three manuals in the downloads. The manual you referring to is under file "69_80114787 Vanguard BIG BLOCK 54, 61 Diagnostic and Repair Ver A"

[KE4AVB]

According the number of views of this thread (over 4000+) there must be a lot fuel issues with the Vanguard 35 engines.