o-ring vs perma-cool

[baddog8it]

In the process of replacing the oil filter adapter with an external oil thermostat and filter.  The oil filter adapter will be replaced by a perma-cool model 3791 dual port adapter.  The problem is that the o-ring that comes with it is too big.  It can be forced into the recess if held in place the whole circumference, but I'm afraid that I'm just as likely to pinch and not form a good seal.  I contacted perma-cool on the day I received it, but have yet to hear back.  I'm tempted to chuck up the part in my drill press and try to machine out the groove a bit.

I've looked online for other o-rings, but they seem to come in 1/8" increments.  I think the next available size would be too small.

Any suggestions?

[Rembrant]

baddog8it wrote

I've looked online for other o-rings, but they seem to come in 1/8" increments.  I think the next available size would be too small.

Do you have a hydraulic repair shop close by?

Bring the part in with you. I use a local shop for all of our industrial stuff, and they have never let me down when finding odd size o-rings. If the 1/8" increments don't work, try the closest metric sizes (if they have them).

[baddog8it]

Loctite makes an o-ring making/splicing kit.  If I remove a very small portion of the o-ring and splice it back together, I could get the right size.

Anybody have any experience with these?

[Rembrant]

baddog8it wrote

Loctite makes an o-ring making/splicing kit.  If I remove a very small portion of the o-ring and splice it back together, I could get the right size.

Anybody have any experience with these?

I've used the Loctite kits before, but it was years ago. I seem to recall there being a little jig to align the two cut ends perfectly. That is the hardest part to accomplish. I forget where I was when I used the kit...but it was either on an offshore oil rig or in a mine up north...both places where there were no other options. It worked, but I have no idea how long it lasted.

[Gary Lewis]

I think I would try to find an o-ring that fit rather than machine the fitting.  That's a critical place in the scheme of engine lubrication, and any leak could cause big problems as well as a big mess.

[baddog8it]

Other than machining the fitting I have (which I don't want to do), all of the other options mean additional time (stores that are open, mail order, etc).  That being said, I think I'll spend the money and get a better fitting that is sure to have a proper fitting seal.

Thanks for all of the input.

I'll have a full blown write up with pics when the project is complete.