I am having an absolute nightmare trying to get this upper oil pan to stop leaking. I have removed the upper oil pan now 2 times and re-installed it only to be cursed with yet again more leaks. Here are some pics of my last attempt at wrapping up my motor build. This is the only thing holding e back from getting some miles on the car, breaking her in properly and getting a nice tune.
Any help is appreciated.

Got myself a fresh set of O-rings for the oil pan:


Got the Grey RTV, since we re going FI, you can't go with what the manual says, we need to go better and stronger...Hence the Grey stuff.


Remove the engine nuts that hold it down to the cross member & hoist the engine up a bit...Only 5 inches or so:


Drop the lower oil pan:


Remove the pulleys...This can be a pain with the radiator and fans in place...its very cramped.


Drop and remove support frame bar...this also helps to hold up the crossmember:


Here you can see that the upper oil pan has been loosened and fell down a bit:


With the cross member lowered, and the steering knuckle removed, there is just enough space to pull down the cross member and get the oil pan out.


Well, my dad, was standing around watching, so I put him to work getting out the old RTV so the oil pan surface is clean and ready for a fresh coat:




Here is a view of a bit of a surprise...I was expecting to find a groove cut to drop the O-rings into, but No Such Luck.


Apparently Nissan wants you to lightly squeeze them into the bottom of the block. Here is a view looking up at the bottom passenger front corner of the block..You can see one of the 2 O-rings in place:


Here are some of the other corners cleaned of old RTV.




Used Brake cleaner to get some of the tough stuff out. Let it air dry, used a different degreaser and finally a dry clean rag to go over the metal one last time. Safe to say it was very clean before attempting to re-install.



BAD NEWS!! After all was said and done, I still suffer from an oil leak in the following 2 areas:



I need some assistance. Anyone know of an aftermarket pre-formed gasket made for high horsepower applications. Not that my application is record-breaking, but I am looking for a different route to go since I tried the RTV Grey, Red combo and failed both times.

Open for suggestions:

 

when I do an oil pan i use a fine wire wheel on my drill to clean off all of the old rtv. I also use the high temp red for all of that stuff.

 

Just use the Ultra Grey. The high temp stuff isn't rated for oil and fluid apps. It's more for sealing turbo downpipes, exhaust manifolds, etc...

 

Randy - as I told you several weeks ago, I'm still going to cast my vote for it being a leaking rear main seal - it is very common, very stubborn to fix, and located right in the exact same area where you are describing.

When the car is left on the ground, sitting, and the rear plastic underpanels removed, where exactly is the drop centered around?

The red rtv is exactly what should be used - it's what Nissan recommends for that area as well, and with the way the o rings sit recessed into the block, there really is no way for oil to leak at those areas, though a rear main seal leak will easily spill oil all over the subject areas.

Otherwise, you might want to consider using a micrometer to check that your mating services are perfectly flat and that you didn't grind too much away at one part

 

the area he circled is at the front of the pan, not the rear. I was thinking rear main seal, too until I saw where he circled.

did you check to make sure you are getting a leak from the oil pressure sensor housing? I had one there, but it was an easy fix.

it is odd that you be having multiple leaks from the upper pan. the RTV is pretty thick and goos (sp?) out to make a nice seal.

 

those o rings you have are usually an orange color that go in there. maybe you have the wrong o rings.


also, make sure you have ALL the bolts back in , there should be five that go in the from the lower oil pan opening. i have seen not having all the bolts in to cause a leak..



the rtv doesnt matter if it is installed properly. orange or grey will work just fine. i like the nissan orange stuff for the upper oil pan.

 

ah..I was looking at it backwards

 

I am getting a lot of mixed info regarding which RTV. I feel that Red should be left for stock motors, but since we are stepping it up with a built block, we should also step up the RTV. So I am voting for the grey.

Yes Adam, The leak is in the front, not the rear. The rear so far has not been the problem.

I didn't shave anything off with a grinder, I used a knife and small screwdriver to scrape out the old RTV.

I cleaned the surface, scraped off the old, cleaned with brake cleaner, dried it off, used a second degreaser product, allowed that to dry, wiped it clean a third time, then applied a layer of RTV.

HOWEVER, due to the placement of the oil pan...back under the engine, I was not able to lay one continuous line of RTV. BUT, in regards to the area that is leaking it was continuous. I even went back and added a second line of RTV, just to be safe. Then I allowed the RTV about 7-8 minutes before putting in place. I lightly bolted it up, making sure the RTV was squeezed out of every corner evenly demonstrating that all surface areas were covered. Then I applied the appropriate torque after another 5 minutes or so.

I let it cure for 2 days before putting any oil back in the block.
I started the car and everything was fine. Once I ran it around the neighborhood and put some load on the car, it started pissing oil in those 2 areas circled. I didn't realize the oil pan was subject to pressure.

Is there pressure building in the oil pan area???

 

The o-rings were purchased from the dealer. Does the color really matter? But I do have to say that the O-rings purchased seemed kind of flimsy. I would like to put some thicker O-rings in there.

And yes, I have done this so many times already, I made sure all 5 (interior) bolts were in before closing her up.

 

man I admire your persistance after reading your thread of building your motor and having to pull the oil pan several times your sticking with it well. Like someone else said I use red rtv but I don't think that's your problem anyways, any rtv should hold up for longer than what you are getting.

 

Oh, the Nissan red stuff is fine to use. That's what I used on my shortblock. I was referring to the high temp ultra copper stuff, that shouldn't be used to seal against oil and fluids. I thought that was what merlin was saying to use. If he meant Nissan red, then I apologize

 

Has anyone heard of racing teams using custom made gaskets with steel sheets and a cork layer or something to that effect?

My father is trying to convince me that I could very well buy a cork sheet and cut to shape and use that, but if there is any kind of pressure developing in that area, the cork might just get blown out. Any thoughts?

 

Nah man, normal RTV should seal it up just fine. There's an underlying problem there that needs to be discovered and corrected. Fabbing up a custom gasket would just be a bandaid, and honestly probably wouldn't work any better than the RTV. I almost wonder if the oil isn't coming from somewhere else.....

Have you double and triple checked that the the mating surfaces are perfectly flat?

Are you following the service manual exactly when applying the bead of sealant? It's very specific on going outside certain bolt holes, but inside of others.

One last thing, it looks as if the front drivers side corner of the upper pan is pretty scratched up...I don't know if that could cause problems or not. Good luck.

 

How much does a new upper oil pan cost? Just thinking if you have to do it again, don't mess with this part again... your time is money too.

 

I just checked with Turbo Toys down in Florida. $90 for a new one. I will be ordering one tomorrow. Good recommendation. I don't understand though, my current one worked well before with the stock block. Now with this new block, I am wondering if that part is perfectly straight...But I will assume that when it was machined, all ends were checked. Assumption is a *****. I am desperate for this thing to be finished with already. $90 at this point won't kill me.

 

Does any engine builder know if there is pressure in the oil pan? Why else would the RTV keep blowing out? I've got the o-rings in place...I don't get it.

 

Do you let the RTV sit first for a while.. Then screw it (pan) on.. wait another hour or two.. then tighten all the way.. Otherwise it may be too wet.. Then let it sit 24 hours at least..

 

hopefully, it isn't your block that doesn't have a flat mating surface.

i think it has to be something else though. the rtv will make up for a gap or irregular mating surfcae,

 

...

 

if your getting a good bead of rtv outside the oil pan when your bolting it up then that should be a good sign that everything is sealed well. Also make sure you don't get too much rtv inside because when it breaks off it could clog the pickup screen. I really don't think the rtv is your problem but rather one of those o-rings or a leak somewhere else that makes it appear your upper oil pan is leaking.