Sealing Oil Pan Flange

[Duke]

I have been having a hell of a time getting the oil pan to seal up on my KA24de.  I have tried just RTV (as they come from the factory), cork/rubber gaskets, gaskets with rtv, etc, etc, etc. and I cannot for the life of me get it to seal.  The pan is custom made using a 1/4" thick flange.  It is flat.  I am making sure that both the block and pan are CLEAN, and then cleaning them again just to be sure (using lacquer thinner).  But no matter what I do,  the flange still leaks where it mates to the block.  It's not major, just a single drop from about 30 minutes of running, but I want it SEALED and DRY!

 

Anybody have any special techniques, sealants, witch craft, or black magic that they use to seal oil pan flanges?  Hit me with them!

[datzenmike]

Where is the drip??? if close to the back might be the rear crank seal.

[Duke]

Drips on the exhaust side of the engine.  I can sit and watch oil weep out and accumulate on the pan rail.  Definitely not the front or rear main seal.

[datzenmike]

Well then the either the pan is not flat, the block is cracked, one or the other surfaces are not clean.

 

Is your PCV valve connected and working? Is oil dripping down from the block vent.

[Duke]

10 hours ago, datzenmike said:

Well then the either the pan is not flat, the block is cracked, one or the other surfaces are not clean.

 

Is your PCV valve connected and working? Is oil dripping down from the block vent.

As I said in the first post, engine is a KA24de, so the PCV is on the intake side of the block (actually attaches to the front cover), and yes it is hooked up to a catch can as I run dual Mikuni's so there provision for the PCV in the intake.  I would be very surprised if the block was cracked, but I will give it a good inspection.

 

Like I originally stated, I'm really just looking for suggestion on sealing.  I have ruled out anything else that may be an issue.  I should also mention that the engine is in the car so I am doing this all overhead.  I'm wondering if even though the block is clean when I install the pan, oil may be dripping down before the sealant has set up and fouling it.

[demo243]

I had trouble with RTV on my KA as well...  down in the same area as well if I remember... I was so mad because it was a fresh build and it start leaking immediately. 

I think this is the stuff I ended up using, and it has been holding good since ---

https://www.oreillyauto.com/detail/b/the-right-stuff-1-minute-5911/chemicals---fluids-16461/glues--adhesives---sealants-19861/gasket-makers---sealers-19581/166cc2694828/permatex-the-right-stuff-1-minute-gasket-maker/25238/6236126?pos=62

Edited May 21, 2020 by demo243

[Draker]

I personally like to go with the OEM sealants. Hyundai/kia grey rtv, Hondabond.. etc.

If you've ever had to remove one of their pan which is held on by just sealant, it's a pain in the ass. I've heard a lot of good things about the right stuff as well. People seem to swear by it, but I've never used it personally.

[G8KeaPoR]

So if the block turns out to be cracked there are some guides out there for welding the block back up Typically you drill straight holes along each crack and stick weld them up. followed by resurfacing the gasket seat.  I recommend letting a machinist do that though.  No RTV is going to fix a crack.  That said if it isn't cracked might I suggest the RTV sealant specifically made by Mazda for the third gen RX7.  I don't know what it is about that RTV but it has sealed things that I couldn't otherwise seal up.   

[datzenmike]

 Does this KA have a crank girdle??? Maybe the girdle interferes with the pan fitment.

[Stoffregen Motorsports]

Good question. If the girdle is touching the pan anywhere, it would cause the problems.

 

Personally, I hate having to seal an oil pan in the installed position. Sometimes I will remove the pan and let it drip for a day or two before I re-install the pan. Best to do this job out of the car on an engine stand, but I get it, that's not realistic.

 

The right stuff if the best RTV I have ever used, period. I use it on oil pans, differentials and diff covers, transmission and t-case housings and adapters. Basically anything that holds oil. If a drop of oil gets onto the sealing surface, the right stuff should work around it, but I would still try for a perfectly dry surface. Apply it around all bolt holes and make sure none of the bolts holes are "wet", meaning they go into an oil cavity. I don't believe any of the oil pan holes on a KA are wet though.

 

Could be your rear seal housing is leaking.

[Duke]

Good call on the crank girdle.  The pan is pretty low profile to clear the rack and pinion setup that I have in my car.  I will take a look at that to make sure I have clearance.  None of the bolts are "wet" so that isn't the issue.  I have the pan off right now and am going to let things sit for a day or two to let all the oil settle.  I have been cleaning the block thoroughly every half a day or so to make sure it is oil free when I give this another shot.

 

I have been leaning towards giving "The Right Stuff" a try.  I have heard good things from multiple sources and I like the short cure time.  Less time for oil to drip down and fowl the seal as thing cure.

[demo243]

1 hour ago, Duke said:

I have been leaning towards giving "The Right Stuff" a try.  I have heard good things from multiple sources and I like the short cure time.  Less time for oil to drip down and fowl the seal as thing cure.

Thats why I tried it. RTV takes forever to cure, I wanted to be able to pull the engine, pull the pan and reseal and drop the engine back in in one day. 

Drained the engine, pulled it, pulled the pan, cleaned the pan and block real well, applied right stuff to pan, installed the pan, let it sit for a bit updsidedown on the stand,  dropped it back in, filled it back up, and ran it same day. Still holding for me *** fingers crossed... knock on wood.... ***

Thought about trying to do it with the engine in the car, but decided it would be just as hard and annoying working around the crossmember and steering linkage as it would be to just pull the engine... I got pretty quick at pulling the engine at the end of the build anyway... and its just easier to deal with the pan when the engine is upside down, less likely to move it before all the bolts are in. 

[Icehouse]

The answer is always Honda bond.  I've tried others OEM glues and they just aren't as good.  You can get two tubes on Amazon for the price of 1 at the dealer.  If the surfaces are clean it works amazing!!  I even used it on my kitchen sink as plumbers putty is a joke.  

[Stinky]

The "Right Stuff" can be found at Napa.

 

Also, you need "Ultra RTV."  Standard RTV wont cut it.  It doesnt have the oil resistance that you need.

 

Remember....silicone is not just for boobs, it has a variety of uses.

Edited May 22, 2020 by Stinky

[grannyknot]

As Icehouse says, Honda Bond has been the go to sealant for decades with good reason, I also like Threebond 1184 and Permatex Motoseal is pretty good too.

[datsuntech]

Hondabond is good, but I prefer the factory approved sealant. From factory Nissan uses a grey RTV, If the engine has been touched by a Nissan dealer it will have orange RTV. 

This is all I use. 

[Stoffregen Motorsports]

Threebond is a major supplier to OEMs. Honda, Toyota, Nissan and others all sell rebranded Threebond products.

 

Yes, I do like the grey RTV used by Nissan, but for oil pans, I feel that the right stuff is a better product.

[grannyknot]

4 hours ago, Stoffregen Motorsports said:

Threebond is a major supplier to OEMs. Honda, Toyota, Nissan and others all sell rebranded Threebond products.

 

Yes, I do like the grey RTV used by Nissan, but for oil pans, I feel that the right stuff is a better product.

I'm going to pick up a tube of the Right Stuff, never tried it because it sounded like a "Can do Anything" product but I've heard a few people now singing its praise so there must be something there.  Thanks.

[Stoffregen Motorsports]

It doesn't dry as hard as the grey "Hondabond",  and it is sort of fibrous, both of which I feel make it better for oil pans and diff covers.

[K Appley]

I second Threebond! Only way to build a non leaking British engine and if it will work on them it will work on anything!

[DanielC]

This is what I do to oil pans to help them seal.  First I take a small ball peen hammer, and hold it on each bolt hole, and hit the face of the ball peen hammer with another hammer, enough to remove the distortion on the bolt holes from previous over tightening.

 

Then I use a feeler gauge to check if the pan has any bend or twist.  This pan is on the bare block, no gasket to check for flatness.

 

I think I used about a .015 feeler gauge for this.

[Duncan]

On 5/25/2020 at 9:32 AM, Stoffregen Motorsports said:

Yes, I do like the grey RTV used by Nissan, but for oil pans, I feel that the right stuff is a better product.

 

Just curious here, but do you guys use this stuff in place of a gasket, or do you use this as a gasket sealer? 

 

 

[datsuntech]

22 minutes ago, Duncan said:

 

Just curious here, but do you guys use this stuff in place of a gasket, or do you use this as a gasket sealer? 

 

 

90s Nissans didn't use a gasket just RTV.

If done right the pan will tend to get bent trying to remove it after it's cured it sticks that well.

You need a special tool to do it without mangling it. 

Similar to this.

 

Or a sharp putty knife and a hammer.

Edited August 2, 2020 by datsuntech

[Duncan]

24 minutes ago, datsuntech said:

Or a sharp putty knife and a hammer.

 

That would be more my style 🙂

 

I had to take the front cover off my motor, and the pan gasket got torn.  Was thinking about buying another gasket and cutting and fitting the front section on, but I'm liking the idea of just using sealer along the front...

[datsuntech]

@Duncan

What engine are we talking about?