April 23, 2017

The Down Side of Brain Storms

Illustration by George Danby

Illustration by George Danby

By John F. Chisholm •

Changing the oil on the Daimler is easy.  The drain plug is at the bottom on the left side of the oil pan.  Simple.  Even I can do it, no problems.

Alas!  Changing the oil filter is another operation altogether.  The car uses an insert filter.  The canister is on the right side of the block.  A cylinder head is immediately above it.  An exhaust manifold abuts it on the right.  The single bolt holding the whole thing together is on top.  That’s right.  In the unreachable, untouchable, unseen and un-seeable area immediately beneath a massive, cast aluminum cylinder head and close behind a burning hot exhaust manifold lies the fastener that retains the oil filter in place.

Good luck.

I should mention that while the canister is visible from below, it’s obscured by the now combined exhaust headers in what has become a large, potentially molten, exhaust pipe.  Yeah.  Removing this filter is anything but simple.  In fact, it’s easier trespassing at the White House.  Much.

Nevertheless, it’s my car.  I have to try.  All the time, effort and money invested in this engine and I’m not changing the oil filter?  Ha!  Keep dreaming.

I waited until the engine was cold.  What else could I do?  (Like most mechanics, I prefer changing the oil and oil filter while they’re hot.  You remove more of the dirty oil.  It’s quicker.  It’s cleaner, too.  Oil has a lower viscosity when it’s hot.)

I jacked the car up and removed the right, front wheel for good measure.  I wanted all the room I could arrange.  Then I unbolted the entire oil filter unit from the car, base plate included.  Sure, it’s four fasteners rather than just one but at least it’s possible to reach them.  Barely.

Please don’t imagine that it was fun.  It wasn’t easy, either.  Perhaps you heard me while I worked.  But once the unit is extracted, removing the old filter is a snap.

But now stop.  Think about this.  Would you want to go through this enormous rigmarole every twenty-five hundred miles just to change your oil filter?
Me, either.  Remember, too, that I’m not done.  The unit still has to be reinstalled once the filter is changed.

That’s what got me thinking.  In fact, that’s when it struck.  The brain storm.  My scalp prickled, growing hot.  Sweat beaded my brow.  My right eye twitched.  The corner of my mouth developed a tic.  “This is sheer genius,” I exclaimed, finger pointing skyward.  I decided right then to re-machine my oil filter canister so that it would come apart from the bottom.  Simple, right?  In fact, why didn’t Daimler do this?

I worked at the transformation all Saturday.  It’s more complex than it sounds.  I drilled and tapped the base, made a long bolt to penetrate the entire length, welded a reinforcing washer to the bottom of the canister and generally carried on.  The seal at the bottom gave me fits.  But finally I came up with a solution, fitted the whole thing back together and checked for leaks.

There weren’t any.  Ta-da-a-a!

Then I cleaned, primed and painted the whole thing, hanging it up to dry.

Leaving the garage, I was positively smug.  Sure, altering that filter unit was a lot of work.  But look at that shining light ahead of me; the goal.  Just think of all that future effort I’ll avoid, thanks to my alteration.

Sunday morning I reinstalled the canister.  My.  I’m glad I started fresh.  A gasket goes in-between the unit base and the block.  I made one.  Of course the old one has to be removed first.  That would be easy if you could get at it.  You can’t.  That much didn’t change overnight.

Then all four bolts have to be restarted while holding the canister aloft in the other hand.  Don’t forget that you’re doing this remotely using a socket and short extender to hold each fastener.  Did you imagine that removal was fun?  Reinstallation is even better.  I promise.

But I succeeded.  Finally.  When finished, I lay back under the car, looking up, admiring my handiwork. “That’s perfect,” I crowed.  “Now all I have to do when changing filters is remove that nut, the canister comes free and ― Voila!  The job is done.”  I peered more closely.  The drop light provided harsh illumination.  Something about the proximity of the nut to the exhaust pipe worried me.

“Okay-y-y,” I muttered on the exhale, drawing out the word in dread.  “Let’s see how it works.”  I grabbed a wrench.

That retaining nut came right off.  “It sure ought to,” I declared.  “Not only can you get at it, the threads are brand new.”

Then I grabbed the canister.  It rattled.  I rattled it harder.  In fact, I shook the whole car, pulling and swearing for good measure.  No matter.  Because that’s where disassembly stopped.

Wouldn’t you just guess?

I’m no further ahead despite all my efforts.

So much for my brain storms.

It turns out that the exhaust pipe is in the way of canister removal from the bottom.

Wake Up, Obsessive Dreamer

By John F. Chisholm •