Vaccum Leak? Please help.

[YosemiteMatt]

Help.

I have a vaccum leak that I can't find. It is coming from the back end of my engine. Comes and goes???? I think it may be affecting my oil pressure.

Any ideas?

 

[YELLAHEEP]

LOL! How's a vacuum leak gonna affect oil pressure? :dunno:

Easiest way to find a vac. leak is to use a propane torch (un-lit of course) with the valve open and point it around the area you suspect is leaking. If the idle picks up a bit, you've located the source.

 

[ColoradoRaptor]

LOL! How's a vacuum leak gonna affect oil pressure? :dunno:

Easiest way to find a vac. leak is to use a propane torch (un-lit of course) with the valve open and point it around the area you suspect is leaking. If the idle picks up a bit, you've located the source.

Was wonderin the same thing....:dunno:

 

[YosemiteMatt]

LOL! How's a vacuum leak gonna affect oil pressure? :dunno:

Easiest way to find a vac. leak is to use a propane torch (un-lit of course) with the valve open and point it around the area you suspect is leaking. If the idle picks up a bit, you've located the source.

Let me say this... I am a newb at shade tree mechanics. The reason I thought they may be related is when I for example..." bring the engine back to an idol after having run it down the road for a period of time, i get some chatter from my lifters or so it sounds like. I thought maybe the oil pressure might be falling do to the vaccum leak." Either way I have a horrible vaccum leak and I have some lifter noise. I recently changed the oil and thought that would help. Do you think it could be rings, oil pump... hell I have no idea!
this is about how I feel at the moment:firedevil

 

[ColoradoRaptor]

Let me say this... I am a newb at shade tree mechanics. The reason I thought they may be related is when I for example..." bring the engine back to an idol after having run it down the road for a period of time, i get some chatter from my lifters or so it sounds like. I thought maybe the oil pressure might be falling do to the vaccum leak." Either way I have a horrible vaccum leak and I have some lifter noise. I recently changed the oil and thought that would help. Do you think it could be rings, oil pump... hell I have no idea!
this is about how I feel at the moment:firedevil

Sounds like your motor has a lot of miles, probably some hard ones! The oil pressure dropping is due to your bearings being worn and the oil pump not having enough pressure to keep up. As long as your pressure is above 0psi you are going to be ok. As far as lifter noise is concerned, there are many 4.0's out there with it and doing just fine. You should have nothing to worry about unless the lifter noise is exteme. Your vacuum leak can be found by doing just as Yellaheep described and then replacing the damaged line.

 

[YosemiteMatt]

Sounds like your motor has a lot of miles, probably some hard ones! The oil pressure dropping is due to your bearings being worn and the oil pump not having enough pressure to keep up. As long as your pressure is above 0psi you are going to be ok. As far as lifter noise is concerned, there are many 4.0's out there with it and doing just fine. You should have nothing to worry about unless the lifter noise is exteme. Your vacuum leak can be found by doing just as Yellaheep described and then replacing the damaged line.

Thank you so so much. That makes so much since.

Do you think replacing the oil pump would be advantagous at all or just let it ride?

 

[ColoradoRaptor]

Thank you so so much. That makes so much since.

Do you think replacing the oil pump would be advantagous at all or just let it ride?

Changing the oil pump would do little to help your pressure as the bearings will still be worn, unless you were to use a high volume or pressure pump. But you would still have the worn bearings to deal with later. I would not worry about it unless your pressure drops to 0psi then you will have no chioce but to rebuild at that point. My father has a 1968 Dodge w200 w/ a 318 that has over half a million miles on it and half of that has been with lower than normal oil pressure. It still runs great and fires up first turn of the key!!

 

[YosemiteMatt]

That's encouraging. Thanks for all you insight.

 

[ColoradoRaptor]

That's encouraging. Thanks for all you insight.

Just run a higher viscosity oil like 20w-50 summer and 5w-30 or so winter!! I like to run a 5w-50 full synthetic all the time but that is me! Oil is a personel choice and some may flame me but I have had great luck with my choices of lubes!! I also run +4 in my auto, and some would flame for that as well but like I said my Junk runs great and my oil pressure is awesome!!