Vacuum components on the ohv?

[Otto]

Does anyone know where there's a diagram or page with all vacuum components for the 4.0 ohv? I'm trying to diagnose what I think is a vacuum leak somewhere..

 

[F150hybred]

Best diagram available will be on your radiator support.

 

[Kalwren]

I guess it would make the most sense for me to post here.

I have a similar question.

I'm thinking that I may have a vacuum leak that is causing a lean condition when my engine is hot.

I don't know how to track down a vacuum leak. I've never done it before. I know how to find a leak when something is leaking air - just squirt some soapy water around until you find bubbles.

But how can I track down a vacuum leak?

 

[Otto]

I dont know whether to laugh hysterically at that last post or agree lol

Same though, there's a whistling sound coming from around the transmission/engine when the motor is hot. Are there any vacuum lines from the tranny?

 

[Kalwren]

Lol...

I've read information that a vacuum leak can cause a lean condition and cause the engine to stutter.

When starting out in first gear, if I'm on a slight incline - the engine will stall out. I have to push in the clutch and reaccelerate and I can drive normally. If the truck is on a downward slope, it's fine. It only does it when it has to go up hill. In order to not double-clutch it, I have to practically break the tire loose and burn out to avoid the stall out.

I've heard it can be a vacuum problem, so I'd like to know where to look and how to trace it out.

After pulling off the freeway, the engine will stall when it's hot out. it'll usually start right back up and I keep driving.

It's a gremlin and it's annoying the hell out of me.

 

[Nhaz]

I guess it would make the most sense for me to post here.

I have a similar question.

I'm thinking that I may have a vacuum leak that is causing a lean condition when my engine is hot.

I don't know how to track down a vacuum leak. I've never done it before. I know how to find a leak when something is leaking air - just squirt some soapy water around until you find bubbles.

But how can I track down a vacuum leak?

Tracking down a vacuum leak is easier then you may think.

First grab a propane torch. Don't Light it. we want the fuel, not the flame.

Start the truck. make sure it will idle or if its stalling have someone keep it going at a steady rpm. steady rpm is important.

Take that propane torch and open the valve Don't light it. Wave the propane around the suspect vacuum lines. If you have a vacuum leak the propane gas gets sucked into the engine and burns causing the engine to rpm up some. so keep the propane away from the intake.

This also works for finding vacuum leaks in intake manifold gaskets.

 

[Kalwren]

Tracking down a vacuum leak is easier then you may think.

First grab a propane torch. Don't Light it. we want the fuel, not the flame.

Start the truck. make sure it will idle or if its stalling have someone keep it going at a steady rpm. steady rpm is important.

Take that propane torch and open the valve Don't light it. Wave the propane around the suspect vacuum lines. If you have a vacuum leak the propane gas gets sucked into the engine and burns causing the engine to rpm up some. so keep the propane away from the intake.

This also works for finding vacuum leaks in intake manifold gaskets.

Wow, thanks for the advice...

That sounds dangerous and scary as hell, lol! Is this seriously the way the professionals find a vacuum leak? It sounds like an explosion waiting to happen.

 

[Nhaz]

the professionals ive seen usually use spray brake cleaner. if anything its more explosive. =>

the propane if it lights outside the engine will go Poof fast

(unlikely unless you have a outside ignition source like a badly hooked up wire) .

The brake cleaner leaves a residue that can continue to burn after the first whoomph!

Its about as dangerous as lighting a BBQ => you don't need large amounts of propane. If there's a leak it will get sucked in pretty quick and the engine will let you know pretty quick as well.

The alternative is to use something that will bog the engine down. Like fogging oil or something. This takes longer to find the leak and then you get left over with fogging oil in the vacuum system and over everything else, also takes a while to work out of the vacuum system.

 

[Kalwren]

the professionals ive seen usually use spray brake cleaner. if anything its more explosive. =>

the propane if it lights outside the engine will go Poof fast

(unlikely unless you have a outside ignition source like a badly hooked up wire) .

The brake cleaner leaves a residue that can continue to burn after the first whoomph!

Its about as dangerous as lighting a BBQ => you don't need large amounts of propane. If there's a leak it will get sucked in pretty quick and the engine will let you know pretty quick as well.

The alternative is to use something that will bog the engine down. Like fogging oil or something. This takes longer to find the leak and then you get left over with fogging oil in the vacuum system and over everything else, also takes a while to work out of the vacuum system.

Lol... Thanks for the info! Maybe I'll give this a whirl and see how it goes. It'll give me a good reason to buy a propane torch. Guys need one of those, right? j/k

 

[travisswett]

you can also use an electrical contact cleaner they are none flamable and will stumbl the engine.

 

[Nhaz]

heh working on any old vehicle. You must have a propane torch. Bolts/nuts need heating at times. I have a really bad habit of snapping them off. Even with the heat.

I seriously like it when I end up with a car that someone decided to cover the entire under body with a undercoat or a oil spray. and kept it up. bolts and nuts actually come off, in the correct shape and in one piece !.

 

[travisswett]

the best way to check is with an electrial parts cleaner ( beacuase it's not flamable) thus not going poof and burning your hair or wires...