Valley pan lesson..

[beanhead]

...And I had to learn the hard way. I'm sure many of you don't need this info but hey if it helps someone having similar issues....Since I fired up my rebuilt 440 a few months back I've had a lot of weird issues as some of you may have read ( a big thanks to all that have taken the time to offer their advice, that's awesome..) big irregular shake, missing, weird vacuum readings, black plugs, idle surging(sometimes) and a few other odd maladies.(considering, this thing ran pretty decent, no smoke whatsoever..) Welp after popping the top on this motor I found, again, oil leaks under the valley pan getting into the ports (and little puddles of oil resting casually on the back of the valves!) I originally used just the pan with permatex #3 but that stuff never sets so it would get hot and gooey and let vacuum leaks develop, then I tried again hi-tacking the paper gaskets to the pan(again hot & gooey) with copper seal on the head and intake surfaces (that stuff seemed to work good) but still failed. Since my intake bolted down pretty easy I was hesitant to blame it, but the block has been decked a little so I decided to take it to be milled..well my machine shop guy (who I wish had built this motor originally because he's awesome) investigated and we found that it was the tin pan that has been causing the leaks all along. With the milled deck, the sealing surface of the heads that is below the ports hangs a little lower than the part of the pan it supposed to seal against. The pan flattened out a tad when I would bolt it together and it's bottom edge lifted ever so slightly, and the bottom edge of the intake does not press it against the head; it would have to 'stretch' the pan to sit it down properly..He assured me no sealer in the world would seal my intake as long as I used the pan, he also said no intake milling was needed in my case(good salesman, huh?) just the separate cover setup with some ultra gray RTV, and the right thickness gaskets.. Point being ( I know, sorry for the long story) If your block has been decked, heads milled, etc...you may consider ditching the tin pan and going directly to the valley cover w/ separate gaskets and saving a headache. Wish I had!

*Edit...The usual means of checking for vacuum leaks never indicated a leak, spraying around the intake etc..covering the carb killed it instantly, etc... but the gague always said otherwise--trust the gague!!

 

[69Bee]

For this misalignment to happen, the heads and decks would have to be milled quite a bit. Also, the front and rear rails need to be milled accordingly, and if they had, the pan would have sat lower in the valley and sealed just fine. I hate having to use a lot of RTV, and usually only use spray copper on both sides of the pan to seal the heads and intake. RTV in the four corners though.

 

[Dennis H]

A small pool has appeard in the valley pan. Second time. Was dry for the first 50k miles. has developed over time. Was recommended use dum dum on threads and 2 gaskets not felpro this time. Also, torque unexpectedly high at 35 lb. Different than op, but current for me.

 

[beanhead]

I wish I knew exactly how much was shaved down, the front and rear were milled also as I checked that against a friend's unmilled block and mine's slightly narrower at the rails( we're only talking thousandths), I guess it just squeezes the pan into a little caddy-wompus as the heads get closer together.......Dennis I've heard about oil weeping up those threads over time? Hopefully that's all it is!

 

[IQ52]

For this misalignment to happen, the heads and decks would have to be milled quite a bit. Also, the front and rear rails need to be milled accordingly, and if they had, the pan would have sat lower in the valley and sealed just fine. I hate having to use a lot of RTV, and usually only use spray copper on both sides of the pan to seal the heads and intake. RTV in the four corners though.

Yep, how often do we not say that for every .010" you mill off the deck that you should mill .017" off the pan rails.

 

[IQ52]

If the pan won't seal all by itself, most likely the intake manifold and head surfaces aren't parallel. Place the intake down with no gaskets and check with feeler gauges the spacing between the intake and head. Mill the manifold to correct the differences.

 

[69Bee]

Alignment could be off too. I use a BHJ Block-Tru, and you align off of the plate. This squares the decks and assures that they are parallel to the crank.

 

[beanhead]

Thanks guys, I appreciate you taking the time to give me advice..Local machinist had me do the same test, and it fit well, the bolt holes in the heads went slightly off-center towards the top of the intake holes.. With a set of thin paper gaskets everything fits perfectly, couldn't get my smallest feeler gague in anywhere. Tried it again with just the pan and no go...maybe I got a poorly qc'd pan who knows...aftermarket

 

[Dennis H]

Thanks guys, I appreciate you taking the time to give me advice..Local machinist had me do the same test, and it fit well, the bolt holes in the heads went slightly off-center towards the top of the intake holes.. With a set of thin paper gaskets everything fits perfectly, couldn't get my smallest feeler gague in anywhere. Tried it again with just the pan and no go...maybe I got a poorly qc'd pan who knows...aftermarket

So, felpro, mr gasket, or? Who else makes them?

 

[beanhead]

So, felpro, mr gasket, or? Who else makes them?

I've only used the felpro...usually spot-on. I thought mopar had one but that may have been for a large-port engine

 

[Mopartisus]

View attachment 421622 A small pool has appeard in the valley pan. Second time. Was dry for the first 50k miles. has developed over time. Was recommended use dum dum on threads and 2 gaskets not felpro this time. Also, torque unexpectedly high at 35 lb. Different than op, but current for me.

I'm having the same problem with oil pooling in the valley pan. Are ya'll saying thread sealer or something similar should be used on the intake bolt threads?

 

[WileE]

No. Intake bolts are not wet.

 

[Daves69]

View attachment 421622 A small pool has appeard in the valley pan. Second time. Was dry for the first 50k miles. has developed over time. Was recommended use dum dum on threads and 2 gaskets not felpro this time. Also, torque unexpectedly high at 35 lb. Different than op, but current for me.

Outside the box, I've seen the pans develop a crack and leak oil causing a puddling of oil on top of the pan.
Careful on that torque. You don't want to strip out the hole threads.

 

[dvw]

Liquid Teflon will seal bolt threads if the oil is wicking up the thread. I've never seen a leak around the bolts since using it.
Doug

 

[Kern Dog]

No. Intake bolts are not wet.

Not wet as far as water but they do have open ends into the lifter valley, right??
I have used Permatex Teflon paste on the intake bolts, "dum-dum" as Dennis called it.
I also use a Mr Gasket intake paper #301 or the Fel Pro #MS90175.

 

[Mopartisus]

Grrrrrr, I appreciate all of the help but I'm getting confused. What would cause oil to pool in the valley pan?

 

[Dennis H]

3rd time is the charm. Mine is dry after a 900 mile romp to Los Angeles. If it were to leak, it would have. Cleaned, schmutzed and reinstalled. Like trying to seal the drivers side valve cover. 3 times and a lot of grief.

 

[moper]

Oil will wick up the threads of the intake bolts and it can show up in the valley and in the low spots where the bolts go through the intake. The intake has to fit properly and I've seen posts saying it was fine to pry them into place to get the bolts in...lol. One should be able to start the bolts with your fingers. Threads in the heads should have been degreased, and use liquid Teflon on the bolts when you assemble.

 

[beanhead]

Grrrrrr, I appreciate all of the help but I'm getting confused. What would cause oil to pool in the valley pan?

Crankase pressure can push oil around the intake ports, or at the front or rear edges where the pan meets the block, if not sealed perfectly. As was the long rambling point of the original post, imperfections in fit between the intake/pan/block will cause leaks

 

[Daves69]

Crankase pressure can push oil around the intake ports...............

It can also cause the pan to flex and crack over time just like any piece of tin flopping around. Years ago big blocks had foil covered insulation between the intake and the valley pan.

Grrrrrr, I appreciate all of the help but I'm getting confused. What would cause oil to pool in the valley pan?

Root cause analysis. Find the leak/where it's coming from.
A leak will likely pool at the rear of the pan. Don't wipe anything off. Take the intake off, turn it over and inspect it for oil around the ports. Also inspect the top side of the pan for any oil leaking from the head intake ports. Take the pan off and inspect it for a crack.