When to change lower intake gasket

[2'91fords]

I know the 4liter has problems with leaking intake gaskets, but how can you determine if they are leaking? I have close to 160,000 mi. Is this an inevitable problem?

 

[TheCableGuy]

I am by far not a great mechanic or anything but I was trying to figure out the exact thing. All I did was hit the lower intake with some starter fluid that I use for my lawn mower and listened for the change in idle. Mine are apparently ok by this test...meaning that I got no change what so ever.

Good luck!

 

[MrShorty]

Other symptoms that show up frequently with a bad lower intake manifold gasket:

1) Pinging under load
2) oil and/or coolant loss. can be internal or external. If internal, it often shows up as deposits on the spark plugs, and is often associated with cylinder #5.

 

[2'91fords]

Thanks. i did try his test before and had no change in idle, no major oil or coolant loss, and my plugs are clean. guess my gaskets are ok for now

 

[savagefan]

If it aint broke don't fix it, and wear a fire suit when you spray ether around a running engine.

 

[Tony H]

Sounds like you are OK for now.
With this engine 'usually' you will get an external Coolant leak running down the front of the engine very close to where the Temperature sensor is. There is a water jacket that runs up into the Manifold right there, there is 1 bolt on the inner side of that jacket but not the Outer side, so it's a weak spot for pressure coolant.

 

[86caprirs]

Well mine is squirting coolant out in a fine mist from the lower intake at the rear r/s back of engine...That will be the time.