DIY fix key fails to activate fuel cut off. w123

[123mike]

My ignition switch was dripping oil on my foot and not sending vacuum to cut fuel. The only way to shut engine off was by opening hood and pushing red lever. I got a 2 Valve fish tank bubbler control and connected the vacuum lines to it.

Positions
RUN. both closed
STOP Left open. Connects vacuum to fuel cut. Engine stops
Release vacuum. Open right
Then close both

I'm so proud of myself....

[Diesel911]

Originally Posted by 123mike

My ignition switch was dripping oil on my foot and not sending vacuum to cut fuel. The only way to shut engine off was by opening hood and pushing red lever. I got a 2 Valve fish tank bubbler control and connected the vacuum lines to it.

Positions
RUN. both closed
STOP Left open. Connects vacuum to fuel cut. Engine stops
Release vacuum. Open right
Then close both

I'm so proud of myself....

The reason that is happening is the oil is getting pulled through the vacuum shutoff diaphragm. If you replace the vacuum shutoff, I will suspect it would work normally, and no oil has no way to get into the vacuum tubing.

However, if you replace the vacuum shutoff on the Fuel Injection pump you need to read up on that because if you get it in wrong the engine goes to full fuel, and you need to block off the fuel or the air to stop it.

A job to read ahead on so that does not happen.

[123mike]

Diesel911, thanks, I will check that out! I thought the key switch was bad and that looked like a too big job. MIKE

[unkl300d]

Mike, Diesel911 is correct.

Additionally, if you have alot of oil present in the ignition vac lines, it might be a good idea to 'flush' it out before testing the new vac shut off unit ! Adding a clear fuel filter to the vac line at the vac shut off valve may allow you to see oil contamination from a future failing diaphragm before it gets messy.