O-ring & Shim from My New Used Engine

[Rob Valdez 79 R65]

I thought you might like to see.

I guess I will go back to using a paper gasket.

I wonder if my filter chamber could be driven in a little more?  

At least none of the cover screw threads were stripped!




click for more

[Rob Valdez 79 R65]

My canister is 0.3mm less deep than Bill's.

My calculation: 4.0 + 0.3 - 3.3 / 4.0 x 100 = 25%.

That is right at the maximum compression recommended.
This is a '82 engine.  Were the canisters safe, by then, allowing me to not use a shim?

I wonder if the local dealer has any paper gaskets on the shelf?  


From Mike V., on Barry's thread:

I wanted to share Oak's percentage formula with all those who aren't aware of it.  It's a pretty simple formula based on a target 10% to 25% O-ring compression. From an old Airmail Airtech article titled "$2000 O-Ring Revisited - Critical Installation Criteria". Oak's formula works well for me and is nice and simple when you wrap your head around it.
Basically...
O-ring + shim - cover gasket (if used) - measured cannister depth / O-ring x 100 = % O-ring Compression. Target is 10 % to 25%.

Here's my numbers plugged in from my 81 R65,
4.0 + 0.3 -3.6 / 4.0 x 100 = 17.5% (no cover gasket used)

Constants:
O-ring = 4.0 mm
Shim = 0.3 mm
Cover Gasket = 0.5 mm

As Oak states in the article "if less than 10% or more than 25% adjustments are needed. Different trials can be made with more shims or the use of the cover gasket.

As a reminder; always use a precision depth gauge when measuring your cannister depth and a good idea to check your new shim, gasket and O-ring thickness as I learned to do thanks to Barry. A check with new filter parts in the box revealed the above values to be in conformance with my measurements.

[Bob_Roller]

I'd install the paper gasket if it doesn't have one, that should put you in about the middle of the range .

From the looks of the metal washer, I'd be inclined to say that the previous filter change, wasn't done correctly .

Looks like the o-ring is deformed on one side, not all the way around .

I'd go with an observation, that these parts were installed at an angle somehow .

To make yourself feel better, take it apart in 500-1,000 miles, and see what it looks like then .

[Barry]

Familiar pictures Rob.  My O ring looked like that - definitely over compressed. I would fit the gasket I guess your going to need a new shim anyway.

[Mike V]

Rob,
Definately a lot of compression. Even at this condition I doubt you're facing a problem unless you're collapsing the filter, but you are at the limits of maximum. Try taking multiple canister depth measurements, maybe 12, 3, 6, and 9 o'clock. May be interesting to see if your canister is not perfectly aligned - mine wasn't to the tune of ±0.5mm. I based my calculation on the average taking note of the high and low. A trial calculation seems to result a 12.5% compression with the use of a cover gasket. I have some extra cover gaskets in the toolbox, I can mail them out to you tonight if you like if you don't have access to a parts supplier or you could make your own if you have some adequate thickness gasket material laying around.

[Barry]

May be interesting to see if your canister is not perfectly aligned - mine wasn't to the tune of ±0.5mm. I based my calculation on the average taking note of the high and low.

Mine was the same Mike I had readings ranging from approx. 2.7mm to 3.00mm. I spent ages with a digital vernier to make sure.  This oil filter business doesn't get any simpler does it.

[Mike V]

Barry,
Funny you mention the difficulty in the measurements...I found it to be a test in manual dexterity as well. I think your fix is a simple addition of a cover gasket. The addition of the gasket may remove some unwanted tension on the filter canister for those cold start-ups.
I also agree this whole excercise is a little like picking the fly sh*t out of the pepper bowl but once it's determined - it's a constant that you can rely on and have some confidence for future oil filter changes. One of those things that if you don't go through the excercise and cause engine damage due to no O-ring compression - you wish you would have. I think what once was called the " $2000 O-Ring " could go well into the $3000 bracket these days.

[Rob Valdez 79 R65]

Sorry Mike - I already buttoned it up and I have the valve covers off.  I was really worried - it too for what seemed like forever to get oil coming out the top end!  So worried, that I loosened the filter cover, but was relieved to see oil dripping, so I tightened it back up.

On the next try or two, oil began coming from the left side first, then the right.

Well, I am off to charge my battery and check my valve adjustments.

Both valve cover center nuts were on with 20 lb of torque! (when I couldn't break it loose with the tool from my tool kit, I decided to use the beam wrench to see what I was dealing with.), and the left one came off with the stud.
But the threads look clean.  I am hoping I can get a tap down in there.

[Mike V]

Jeez, sounds like our bikes are related. My left side center v cover stud came out with the nut on my bike also. There was no thread damage so I double nutted it and reinserted it with some red locktite. Some say to use blue. Why do you need to tap? Are the threads damaged? 20 pounds is way too much. I never use a torque wrench on the covers just by feel and sequence with the 10mm nuts to make sure the cover gasket is snug and sealing. I have recommended torque values if you're interested, I can look them up for you or I'm sure Bob or someone has advice for that.

[Rob Valdez 79 R65]

Torque value for the center nut?  Nah - if it falls off, I'll run without it, just like I did for the past many years.  Ask Ed Miller - he understands.

As for the side nuts, I haven't needed a torque wrench in 30 years.  why spoil a good thing, now!