'01 Mercedes AMG, Problem Solving

Mercedes CLK55 – Oil Filter Housing Leak Solved

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The 2001 CLK55 engine sprung a leak, evidenced one morning by a visible oil puddle behind the right front wheel. It was a narrow lake of oil, probably no more than a couple tablespoons, originating near the rear of the engine. After putting the car on ramps I crawled under to take a look.

The evidence
The likely sources, the oil filter housing and the oil filler cap. Yellow is pointing at filter housing that must be removed

I uploaded the photo and had a bit of consultation with ChatGPT as to the possible source of the leak, and eventually discovered there was oil on the front of the engine below the oil filter housing, and a bit near the oil filler cap.

The yellow arrow points to the oil filter housing, which needed to be removed. I feared the worst, but found that it is a simple job. There are two rubber seals between the filter housing and the finned oil cooler, attached with four bolts removed with a T30 socket. The filter housing also has upper and lower halves, with a rubber seal between them. These are held together with a large hollow “bolt” that requires a 46 mm socket for removal.

Four T30 socket bolts hold this cooler to the filter housing
This bolt gives the most grief, tight space for a ratchet down there
That one!
At bottom of housing, the 46 mm “bolt”
I used a 1 13/16″ socket, which set me back $20 at Tractor Supply
The torque spec is around 50 lb/ft, but it took two pulling on a 3 foot lever to break it loose.
Old flattened, hard rubber seals
Found the seals online at Autozone
Bottom seal lubed and in place
Ditto for the two seals between housing and cooler
New filter going in, job nearly finished
All buttoned up. After a couple long drives, not a drop of oil under the car!

When I first spotted the oil, I was tempted to donate the car to charity. However, what I feared would be a time consuming, difficult, and expensive repair turned out to be simple and straightforward.

I am an advocate of AI for help diagnosing car issues but ChatGPT was a bit off with this repair. First it insisted that I could replace the oil level sensor without removing the oil pan, telling me that it was removed from bottom of the pan, held by 3 bolts. NOT!

And then it was pretty clueless about the 46 mm bolt securing the upper half of the filter housing to the lower half that bolts to the engine block. By providing photos and working through it, I’m hoping it got a little smarter.

No plastic plate secured with 3 bolts down here
This is the oil level sensor, not critical, but annoying
Seen here roughly above the drain plug, it’s accessed after removing the oil pan

Next up, in a few thousand miles, replacing that oil level sensor. And then… fixing the ABS/ESP/BAS fault, which means having the pump rebuilt.

'01 Mercedes AMG, Problem Solving

Mercedes CLK55 – Oil Level Sensor Replacement

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The oil sensor quit working a few months ago. I would have let it go since I check my oil regularly, but in my pursuit of leaks it became clear that the sensor was a problem. These engines have an upper and lower oil pan, both cast aluminum. The oil sensor is bolted to the upper oil pan and is accessed by removing the lower pan. Part of the oil sensor protrudes through the upper oil pan in a little flat area, approximately above the drain plug, where a connector plugs it into the ECU. The rubber o-ring was no longer doing its job of keeping the oil inside the engine.

On the CLK55, the oil level sensor cannot be replaced without removing the lower oil pan.

It was a mistake to have F1 on the TV, apparently I can no longer multi-task
The sensor shows itself here, above the drain plug
Where the plug connects sensor to ECU

I used the E10 socket to remove a dozen bolts securing the lower oil pan, plus two more holding pipes to the pan. Then I removed the two brackets holding the sway bar in position under the oil pan, allowing it to swing down and out of the way. As long as the front wheels are at the same height there should be no tension on the sway bar, and it doesn’t matter if they’re on a ramp like mine or hanging freely.

The pan felt like it was welded on, and wouldn’t budge even with several hard raps with the rubber mallet, side to side and front to back. I sprayed PB Blaster liberally all the way around where the two pans join and let it sit overnight. The next morning, a couple more knocks with the mallet broke the seal loose.

Essential tools
Sway bar bracket
Finally separated
Oil level sensor goes through upper pan here
O-ring clearly not doing its job
New sensor, attached by four E10 bolts
Lower pan cleaned up using razor blades, abrasive pad, and chemicals
The upper pan also should be spotless
Take care cleaning the mating surfaces, I relied on Goof-Off and engine degreaser to loosen the old sealant then with a light touch used the straight razor blade and some Scotch-brite to ready the upper and lower pans for fresh sealant.

Pans bolted back together
These ramps give me 20 inches of elbow room… less than $200
The Mercedes sealant, Permatex Ultra-grey also does the job
The bead should be a couple millimeters wide.
The service drop-off area at Mercedes dealership. The sealant was twice as expensive here.

I do like the local Mercedes dealership, and they had taken care of our ML diesel before we swapped it for the Subaru Outback. It’s a great looking facility and of course the new cars on display are marvelous, but parts and service tend to be pricey. On the plus side, the parts department is totally open and honest about where the parts can be found at lower prices.

Now, with the oil filter housing and oil pan leaks addressed, hopefully the CLK55 engine is buttoned up for a few more miles. Next on the agenda is the transmission oil pan which seems to have sprung a leak.

Conversations, Elections

Who Is This Candidate, Really?

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Sources of information

How do we find out who a political candidate really is? We can follow the money, examine who is financing the campaign, compare the candidate’s public statements with voting records, and look beyond campaign advertising to see what the candidate has actually said and done.

THE MONEY

Find out who is backing the candidates

Federal Election Commission campaign-finance database — the primary source 

This should be the foundation. The FEC lets you search every Senate candidate, the candidate’s authorized committee, contributions received, PAC contributions, and—particularly important for our purposes—independent expenditures supporting or opposing that candidate.

Issue One — particularly good for the dark-money layer 

This is becoming especially useful in this election cycle. Issue One is already tracing 2026 money flowing from nonprofits into the major congressional super PACs.

OpenSecrets — best first-pass analytical source 

Utilize this as your initial lens to pinpoint major contributors, key industrial sectors, and independent groups; subsequently, pivot to raw FEC records to substantiate the specific financial movements.

THE CANDIDATES 

Who are these people, what they have said, and what they have done?

OnTheIssues.org — 2026 Senate races

It has already assembled a 2026 Senate section, organized by state and candidate. More importantly, it collects statements by issue from campaign websites, press releases, debates, interviews and previous public statements. It preserves dated quotations, which helps you track changes in a candidate’s position.

Ballotpedia

Ballotpedia is a good starting point for biographical information: age, education, occupation, previous offices, electoral history, endorsements and campaign information.

Vote Smart

Vote Smart is especially valuable for candidates who have previously held public office because it combines biography, issue positions, ratings by interest groups, public statements and voting records.

Congress.gov gives us legislation sponsored and cosponsored, roll-call information and congressional activity.

For senators, U.S. Senate roll-call votes gives us the actual voting record.

For representatives running for Senate, U.S. House roll-call votes does the same.

That gives us something measurable.

For very recent issues, add contemporary news searches

This is necessary because the databases inevitably lag behind events.

So for rapidly developing subjects, search AP, Reuters, local newspapers, television interviews, debate transcripts and the candidates’ own statements rather than depending entirely upon Ballotpedia or OnTheIssues.