Not shutting off

[fireball]

Greetings all,
I'm pretty sure I saw someone mentioned this before but the Tappa talk search function is less than stellar. My BJ 74 has just started the strange habit of not shutting off when I turn the key off and remove it from the ignition.

Can anyone help explain why this is happening? Or better yet, how to fix it!

It is quite embarrassing to have to stall it out after coming to i'll stop in a parking lot. Especially because usually by this time a sizable crowd has gathered to oogle and awe over the JDM diesel goodness!

 

[peterb]

The shut off is vacuum activated. It's likely that the hose is leaking and not providing sufficient vacuum to kill the engine. You can search this when you're near a real computer.
Good luck
Peter

 

[jblueridge]

Yeah, my Vacuum Shutter Valve (Toyota name for it) stopped working and it caused the motor to die. With the hose disconnected (as knowledgeable folks here directed) engine would run forever if I didn't stall it out.
Definitely check the mushroom shaped diaphragm mechanism connected to throttle/air intake and the small vacuum line attached to it.

 

[jblueridge]

This thread is my reverse situation
https://forum.ih8mud.com/threads/13bt-died-while-driving.843828/
but it explains the whole deal.

 

[Oldtoy74]

Pretty standard for the bj74, things to check specifically is the vacum switching valve, located above starter , also check vacum pressure to butterfly intake, and where my issues was, the clutch booster seal has ripped thus not creating enough suction to pull the butterfly closed. Have a read through the posts it will get clearer more the you read.

 

[Malahki]

Yup clutch booster is a common cause of this. Is your pedal getting stiff? In the meantime until you diagnose and repair the problem manualy pull the lever on the bottom of the vaccum diaphram unit to shut off the engine

 

[fireball]

Yes. Pedal is stiff intermittently. Here is live shot from a few minutes ago. A few bars of cell service but no internet cafes around

 

[Malahki]

Great Pic!! I've always missed that photo opp when in Moab. What trail is that off of?

So your best bet it to replace the little output seal on your booster. Here is a link to another thread on the subject as well as a pic of the seal with part number
https://forum.ih8mud.com/threads/bj74-clutch-booster-question.281615/

 

[fireball]

Many thanks for the quick and helpful replies. Any chance of it getting too much worse or failing completely? Both the engine not shutting off and the heavy clutch pedal are intermittent now. We have another day or so of dirt roads planned then the highway back home.

That photo is at the end of the top of the world trail about an hour northeast of moab.

 

[cruiserdan]

The issues are likely interrealted and it will continue to deteriorate. Vacuum issues will also affect shifting in and out of 4WD.

 

[fireball]

Dan you are a prophet!

Driving down the highway for a few hrs now the green illumination ring of the h4 button is intermittently slightly illuminating. Maybe that is just the trucks way of telling me it's angry at being done with all of the fun off road driving of the trip and now on to the 1800 mile slog across Route 70 back home…