hey there!

so Im trying to pin point where an oil leak is happening. for a while I noticed that the valve covers would leak oil so i just recently replaced the gaskets. unfortunately I snapped one of the bolts on the valve covers (the first one up front up towards the carburetor) but Im not seeing any leaks from the valves covers, despite the missing bolt there. I was following the instructions on the torque, however my torque wrench failed to notify me when I reached the limit, and I don't really know what 11 to 14 foot pounds feels like so here we are, classic rookie mistake. I will tend to that when I can of course.

However, I noticed a large amount of white smoke coming out from the back of the engine originating from the exhaust manifold, and the exhaust breather (I think thats what it's called, its like a small clothes dryer vent tube that connects from the exhaust manifold into the snorkel of the air filter) is like a chimney of white smoke. Those are the only spots where I see white smoke.

there is oil underneath the engine near the oil pan and transmission, and past the headers going down. I don't think the head gaskets are messed up cause it drives wonderfully, and I dont think its the valve covers cause Im not seeing any leaks from there, despite the missing bolt.

my conclusion is that the exhaust manifold gaskets are shot. can any one help me confirm this?


one more thing. while I was replacing the valve cover gasketsI noticed a vacuum line that was broken off. its a metal tube that runs from the exhaust manifold, then transfers to a small gauge rubber tube and then It connected to a small metal tube that doesn't have any threading on the other end, and I don't see evidence of the small metal tube being "snapped off" or pinched off of something. I could not for the life of me find where it went!

i have videos to show the white smoke issue and and pictures of the mysterious vacuum line, or whatever its function is.

pardon my ignorance on these matters Im still fresh at this

 

Hey, Montag! It will help if you tell what engine? You mentioned "valve covers", so I am guessing a V8.

 

sorry, Correct!

its a 5.0L 302 V8

 

11 to 14 FOOT lbs sounds like to much for a litte valve cover bolt.
You sure that was not INCH lbs?
​​​​​​
A 1/4" stub ratchet is all you need and don't go ape with it.
Dave - - - -

 

according to the haynes book it says 132 to 168 in-lbs for small block engines which if i converted correctly translates to 11 to 14 foot pounds

 

The factory Spec is 8-10 ft lbs for AL valve cover and steel gasket
4-6 Ft lbs with steel valve cover and cork gasket.

 

You will learn quickly why the Haynes manuals are trash and should not be trusted. Also I should point out a beam style torque wrench should always be used on critical measurements.

 

Now that iv'e learned that all the information I carefully gathered was in vein on my first go lol, does any one have a direction about the white smoke coming from the breather and the back of the engine near the exhaust manifold?

 

White smoke is normally associated with oil burning.

 

i understand that, Im wondering if its burning because oil is leaking on to the exhaust manifold. its not leaking from the valve covers, so i think the gasket in the exhaust manifold is busted and needed to be replaced in order to stop the burning of oil. Hopefully my hypothesis makes sense.

 

So you are saying the gasket between the manifold & head is bad and why the smoke is coming out?
Is there ant white smoke coming out the tail pipe? If not then I would say it is not coming from inside the motor thru a bad manifold gasket.

Could it be old oil that is on the manifold from before the gasket change?
Can you post a picture of where this smoke is coming from we may see something you don't.
Dave ----

 

All:
I have oil in the same area too: right past the oil pan and in front of the transmission (mine is a AOD). No white smoke from the tailpipe though.
BTW, I have a 1986 F-150 4X4 with a 5.0 302 EFI. Did a Carfax and found out that it has 149,000 miles on it.
I too would be interested to learn what the gurus in the forum think is the possible cause or causes and what if anything can be done to stop the leak.

 

first you need to clean the living crap out of the engine to figure out where the leak is coming from, and start there. Either rotten gasket or overtightened (and compromised gasket integrity), or something of that nature. If it started after you did something, whatever you did "may" have created the issue. Real easy for valve covers to get overtightened and leak like a faucet. I use one hand on valve cover bolts, I don't use torque wrench, because I guess I'm not that concerned it's a critical measurement. Maybe I've done it so much I don't think much about it.
if you use rubber valve cover gaskets, don't use silicone also, it'll creep and slide. if you use cork, you can glue to the valve cover, let it sit up, and then use a very heavy grease (think wheel bearing grease) on the side that touches that head and those will be removable in the future and can be reused, if torqueing doesn't ruin the cork after once or twice. my favorite are the new gaskets that are rubber with metal inserts to keep you from going too far on your torque. Very easy to create valve cover leaks and it will certainly smoke like the proverbial freight train.

 

Update:

So i swapped out the the valve covers for bran new ones and got bran new Gaskets and finally it is not leaking from the valve covers. how ever there is still white smoke coming up from the same spot. Back of the engine left hand side. I did notice a bubbles coming out of the connection of the air crossover. Could oil be leaking from there?

also, I found this on the ground while I was swapping valve covers. I have no idea where it came from but it felt like it had fresh oil on it as if it was recently on the truck.The spring fits perfectly on the Bolt/thing and I assume the washer is a part of it.



the only thing I know I put on the ground was the air filter housing, the air filter, and the PCV valve with its tube that connects to the carb. thats it. everything else was contained in the engine or was bran new, so there couldn't have been oil on it or that grimy.


Also, i notice my truck when running feels slightly different, a little rumbly, like almost not enough gas to keep it running but it runs fine when out of idle. any ideas?

 

in my first post i have two videos showing where the white smoke is coming from. do they not work?