Oil pan gasket

Coupefan

Coupefan

True Classic
I've always used those thin paper-like gaskets on the oil pan. While cleaning up yesterday, I found a pretty thick rubber-like gasket, clearly SOHC oil pan gasket. I'm not sure where and when I got it...I have so much crap (car parts) stored everywhere. Thinking it's for a steel pan, not an aluminum? Thoughts? Not petrified, so still usable.
 
Coupefan said:
I've always used those thin paper-like gaskets on the oil pan. While cleaning up yesterday, I found a pretty thick rubber-like gasket, clearly SOHC oil pan gasket. I'm not sure where and when I got it...I have so much crap (car parts) stored everywhere. Thinking it's for a steel pan, not an aluminum? Thoughts? Not petrified, so still usable.
Click to expand...
Correct, paper for the X1/9 with aluminum oil pan, rubber for the steel oil pan on other SOHC applications.
 
Yep. No idea how I ended up with it. Likely one of my early 2000s EBay 'lot o'misc pieces' purchases
 
By comparison with experiences of rubber pan gaskets on other engines, I would think it should work really well on the aluminum pan. Would the added thickness create any obstacles?
 
Been using the thick rubber gasket for years. I've always had good luck with them but you need the right length bolts to use them.
 
MWB sells the rubber version, as well as the standard variety - I used it this last time around. I like it. Do need to check the bolts over time however, they do seem to require retightening.
 
The rubber looks more substantial, but it creeps with heat and time. Unless your flanges are totally jacked-up, you are better off with the paper gasket as its compressed thickness will be much more stable and thus retain bolt tension far better. You'll be forever re-tightening the bolts with the rubber. The rubber is used with the stamped pans because they aren't as stiff or flat and need the extra gap-filling ability that the rubber offers.
 
A related event. I did some more cleaning, found another rubber oil pan gasket. But this one had chew marks in it and missing chunks. I believe I've located a rodent infestation. This is not good.
 
And just to muddy-up the water a bit more...I'll throw this out.

Ages ago most gasket makers offered "cork" gaskets for oil pans and valve covers (not necessarily Fiat application, but speaking generally). I liked them but others did not. For me they had just enough 'give' or 'cushion' to make up for any variances better than paper could, but did not have so much 'squish' as to require constant re-torquing, and did not 'creep' like rubber can.

On the subject of having to re-torque regularly, I've always thought the use of a "constant tension" type bolt would be a good idea for oil pans and valve covers. I'm thinking something along the lines of the bolts used on "constant tension" hose clamps (see the example photo below). But to my knowledge they haven't made them.
MMCLAMP-325T_2.png
 
I have to agree with Paul's assessement of the rubber version. I will likely have to replace it with a original, as I don't want to be removing the crossmember every 6 months to access those innermost bolts...

Jeff, I would say that would be serious overkill, nevermind extremely fiddly to work with. I never had an problems with the pan bolts loosening over time with the stock gasket. The only slight pita is getting a little sealant in the just the right spots to cover where the front & rear engine seal covers meet the pan gasket.
 
The 124 motors use thick rubber oil pan gaskets (sheet metal oil pans) but the bolts all had odd looking spring washers and these bolts never got loose. That was my comfort zone so I was confused the first time I took an oil pan off an X and found the bolts just used simple washers. Now I understand the difference.
 
carl said:
the bolts all had odd looking spring washers
Click to expand...
Carl, its been ages since I had my hands on a 124. Is this the one?
fiat parts 54-4373.JPG


If so then it reminds me of the "Nord" type lock washers (which work very well):
sp_washers1-625x287.jpg


If that isn't it then please see if you can find an image to show, thanks.
 
Thanks Jeff. The Fiat washers shown sort have have both features reminiscent if the "Stage 8" header bolt locking kit and the Nord washers; in this case the flat sides of the washer will hit the pan and prevent the washer from turning (much like the tabs on the Stage 8), and the washer's 'ribs' will hold the bolt head (much like the Nord washers).
 
Dr.Jeff said:
On the subject of having to re-torque regularly, I've always thought the use of a "constant tension" type bolt would be a good idea for oil pans and valve covers. I'm thinking something along the lines of the bolts used on "constant tension" hose clamps (see the example photo below). But to my knowledge they haven't made them.
View attachment 4482
Click to expand...
You'd make a good inventor! The idea of stretch bolts is basically just that. The metal is deformed past yield but still within the elastic limit so it is like a spring. Even if things "relax" a little with heat cylces, time, etc, you still maintain tension. Also, I have seen shoulder bolts with springs on exhaust bolts where there is a spherical joint.
8802.jpg
 
Yea, that's the guy....too much work for me to dig one up and take a picture but I guess I should have.
 
phillips82 said:
Rubber gasket and a dab of blue loctite on each bolt. Works like a dream.
Click to expand...
Yep - the loctite makes all the difference in the world. This is another example of a joint that doesn't require a lot of preload in the fasteners... just need to compress the rubber adequately, and the force required to do that isn't enough to keep the bolts in place without the threadlocker or some form of sophisticated washer.

You'll find that if you use the paper gaskets you'll need to be appreciably more careful about evenly torquing the bolts to a level high enough that they won't loosen - and that's much more torque than you can use with the rubber gaskets.
 
If a thread-locker is used there may be a couple considerations. Primarily, as we are talking about oil pans, be sure to clean all oil residue from the threads on both sides of the interface (bolt and block).

Paul Valente said:
You'd make a good inventor!
Click to expand...
Thanks Paul, actually I am an inventor of sorts. As a professional consultant to automotive aftermarket companies I have developed many new products and applications.
 
You must log in or register to reply here.
Back
Top