Changing the oil pan gasket

[BDA]

Ok, this seems like a silly thing to ask about. I've changed oil pan gaskets lots of times. It was a long time ago but it's not rocket science and I still remember *basically" how I did it:

Drain the oil, loosen all the bolts holding the pan and pull the pan off. Clean out the oil pan and clean the mating surfaces of the block and oil pan. Spread a smear of silicone gasket maker on the pan and stick the gasket on it making sure all the holes align. I think I had to size the cork gasket around both ends of the crank trimming it with a sharp knife. I don't remember if I glued those crank gaskets to the pan or the block but I used silicone goo. Then I spread silicone goo on the gasket and the crank seals. Then I bolted the pan back in place making sure to tighten them evenly and not to over tighten them

As I say, that has always seemed to work for me but I was looking around on youtube and one guy who seemed to know what he was doing glued the gasket to the pan with super glue and did not use any gasket dressing at all. Another guy warned against using RTV silicone. That got me to wondering if my old technique could be improved upon.

I suspect there are at least several ways to skin this cat so I'm wondering if you have a particular technique that works for  you that you'll share.

[jbcollier]

Silicone sealer can be tricky.  Used sparingly, and allowed to set, it will work just fine.  The trick is not to use so much that it forms “globs” on the inside.

It really depends on the design of the pan/block.  The Renault is flat all round so I use yellow contact cement and glue the gasket to the pan.  I then use Permatex Aviation Gasket Maker #3 on the gasket and that’s it.  No leaks though I do have to snug the oil pan bolts every 5k or so.

IIRC the TC pan has rounded sections at either end.  There I would use silicone sealer on the rounded sections after gluing the gasket in place, especially in the corners — though remember the sparingly bit.

There is no one right way.  Just be careful and thoughtful about what you do… and don’t overdo things!

[BDA]

Thanks for the advice, JB! I agree that silicone should be used sparingly. Using too much is a common mistake.

[EuropaTC]

Firstly I'll second the general feeling that silicone is fine in moderation and that's what I normally use.

Here's a real blue sky one for you..... the sump gaskets on my Europa are currently rubber, cut from a sheet using the sump itself for patterns.  And the cam cover gasket is the same, cut from a sheet using the cam cover as pattern. Both held in place with a very thin smear of silicone.

They work well, no leaks, no relaxation of the joints that I've found although it's not a daily driver so maybe that's why.

Cork is just so 20th century.....

Brian

[BDA]

20th century… 

What kind of rubber do you use and where do you get it?

[EuropaTC]

Nitrile, fairly standard for oil resistance although I think if you are using it for unleaded petrol there's a modified version. I'm not 100% sure on that, it's a vague memory from t'internet.   Fairly soft, 60 Shore, nothing special.

There were two reasons to try it, firstly the modern cars I've worked on have used rubber cam cover gaskets with no leaks and they are also re-usable. I've had both sump & cam covers off and simply cleaned & re-stuck the rubber gaskets.

Brian

[Bryan Boyle]

Thanks for the advice, JB! I agree that silicone should be used sparingly. Using too much is a common mistake.

And end up with snakes (or worse) in the pan...lol.  I think the illustrations in Wickins' book are instructive; thin bead, smooth down.  Don't forget on the TC you have to drop the exhaust from what I can see.  Renault not necessary to do so, if memory serves.


Although, there is a lot to be said for aviation form-a-gasket.  Smells better too when it warms up. 

[BDA]

That's an interesting idea for sump and cam cover gaskets, Brian. I used to help a buddy with his big V-8 Mustang race car and it had rubber valve cover gaskets. I didn't like them I think because I was afraid they would squish out but they did seem to work. I don't remember what his oil pan gaskets were made of. I had no problem with the thick cork valve cover gaskets on my Spridget but I hated the thin cork gasket for the cam cover of my BDA. They were redesigned and now they are a rather rigid sheet with a sealing strip, probably made of some rubber, that does the actual sealing. MUCH better!!

Speaking of snakes, I once knew a guy who used too much silicone on his fuel system (I assume it was for sealing his fuel cell in his race car). One day, he couldn't get it started. For some reason, he wasn't getting any fuel. it turns out he had used too much silicone and it formed a rope in his fuel line! It's easy to use too much of that stuff and it's not as impervious to gasoline as some think.

Yeah, it's a bit more involved on a TC; more so on my car since it has a dry sump. I have a new clutch disc that I'll be installing sooner rather than later and that will probably be when it gets done.

Since I got interested in this, I've gotten a better understanding of just how bewildering the assortment of gasket goos there are. Just one example is the Aviation Form-a-gasket #3 JB and Bryan mentioned. I have a can of something very similar also from Permatex called Super 300. From Permatex's website, the difference seems to be that Super 300 is formulated especially for synthetic oils. Then there's the different types of Permatex gasket goos (RTV, anaerobic, and solvent based) and different kinds of RTV (conventional, ultra, and elastomeric), and on and on. Permatex also makes a silicone goo that is specially designed or synthetic oils (of interest to me since I use synthetic oil) and another specially designed just for gear oils. And that's just some of the gasket goo that Permatex makes! Then there's Hylomar, gasket shellac, and a host of other gasket goos out there!

It's been a ride so far!

[Bryan Boyle]

That's an interesting idea for sump and cam cover gaskets, Brian. I used to help a buddy with his big V-8 Mustang race car and it had rubber valve cover gaskets. I didn't like them I think because I was afraid they would squish out but they did seem to work. I don't remember what his oil pan gaskets were made of. I had no problem with the thick cork valve cover gaskets on my Spridget but I hated the thin cork gasket for the cam cover of my BDA. They were redesigned and now they are a rather rigid sheet with a sealing strip, probably made of some rubber, that does the actual sealing. MUCH better!!

GM thought they were being progressive with their engineering when they released the first Northstar V8s....the block was actually a split block to pick up the crank...and the two halves were a neoprene gasket with NO locating tits to keep it from moving in between the two halves' bolts.  Guess what?  Luckily I had a GM service contract...because they had to split the case in situ and they had a running change that resolved that problem (among others in that engine...was a strong performer, but its longevity of the early versions was less than stellar).

Speaking of snakes, I once knew a guy who used too much silicone on his fuel system (I assume it was for sealing his fuel cell in his race car). One day, he couldn't get it started. For some reason, he wasn't getting any fuel. it turns out he had used too much silicone and it formed a rope in his fuel line! It's easy to use too much of that stuff and it's not as impervious to gasoline as some think.

Yeah, it's a bit more involved on a TC; more so on my car since it has a dry sump. I have a new clutch disc that I'll be installing sooner rather than later and that will probably be when it gets done.

Since I got interested in this, I've gotten a better understanding of just how bewildering the assortment of gasket goos there are. Just one example is the Aviation Form-a-gasket #3 JB and Bryan mentioned. I have a can of something very similar also from Permatex called Super 300. From Permatex's website, the difference seems to be that Super 300 is formulated especially for synthetic oils. Then there's the different types of Permatex gasket goos (RTV, anaerobic, and solvent based) and different kinds of RTV (conventional, ultra, and elastomeric), and on and on. Permatex also makes a silicone goo that is specially designed or synthetic oils (of interest to me since I use synthetic oil) and another specially designed just for gear oils. And that's just some of the gasket goo that Permatex makes! Then there's Hylomar, gasket shellac, and a host of other gasket goos out there!

I'm partial to the aviation goop; I've used it successfully on a number of lycoming and continental rebuilds between the case halves...and besides having a BIG can of it, it somehow lasts for 2000 hours (most of the time, if you follow the case sealing directions religiously).  On aluminum, I prefer the non-acetic acid RTVs that they have out there, and of course, there is proseal (which we use on wet wings to seal the joints and fittings) and high-temp RTV for areas that get hot.  I know Wickens doesn't like Hylomar anymore (there are better solutions).

I think the key is use it sparingly, thin bead, smooth out...it's just meant to seal, not make up gaps where precision manufactured parts should require minimal sealing; that's what the neoprene/cork/synthetic stuff is there for (of course, that includes the head with its copper cylinder seals...)

[BDA]

That's interesting that Wickens no longer likes Hylomar. I used to use it on the end cover of the Hewland in my race car. It was easy to clean up and so was handy for that application. I have a tube now that I've used once to seal the head to cam carrier joint and it seems to be working well there but I admit, I don't use it generally.

You got my attention talking about "aeroplane" engines!

I haven't decided how I'll do my oil pan gasket yet. I have two sets of oil pan gaskets so I don't think I'll cut my own rubber gasket even though it sound intriguing.

As always, I appreciate everyone's comments!

[EuropaTC]

I haven't decided how I'll do my oil pan gasket yet. I have two sets of oil pan gaskets so I don't think I'll cut my own rubber gasket even though it sound intriguing.

To be fair, I didn't start off thinking "I need a rubber gasket on the sump".  I originally wanted a cam cover gasket because the MR2 (and others) had them and were so easy to seal. The trick of course is to locate the gasket and generally the surfaces are designed to retain the rubber, not so on the Lotus cam cover. And you can buy rubber TC cover gaskets which are rubber/Aluminium composites to prevent movement (Cometic, £25 each) 

There's no real pressure either from inside or bolting forces so I thought plain rubber tacked in place for assembly would work and it did. After that I had sheet left over so when I had to remove the sump later on, it was a "I wonder if...." moment.

Brian

[Bryan Boyle]

I haven't decided how I'll do my oil pan gasket yet. I have two sets of oil pan gaskets so I don't think I'll cut my own rubber gasket even though it sound intriguing.

***DELETIA***

There's no real pressure either from inside or bolting forces so I thought plain rubber tacked in place for assembly would work and it did. After that I had sheet left over so when I had to remove the sump later on, it was a "I wonder if...." moment.

Brian

"I wonder if..." is the source of all great advances in our journeys...taking a philosophical detour....to me, ranks up there with "it's easier to ask forgiveness than to ask permission..."

[EuropaTC]

"it's easier to ask forgiveness than to ask permission..."

and so much quicker....