Bad Fuel Cap

[emerydc8]

I had been smelling fuel while working on the rear brakes of my car but couldn't find any leaks. I took the car through emissions testing today and they discovered that the gas cap had failed. At first, I thought it was BS and was preparing for an argument, but they showed me where the rubber seal was cracking and letting fumes through. I don't think this cap was that old -- Maybe three or four years. It's not a bad idea to put new fuel caps into your next parts order as preventative maintenance.

 

[gerryvz]

You can get a new rubber seal for the cap -- I don't believe you have to buy the entire cap. Same for the oil cap and coolant expansion tank cap.

Those hot climes in the south and southwest are NOT kind to rubber. I found that out very quickly living in Texas. You tend to only get 25-50% of the life on rubber items in those climates, that you do in more moderate places like the Pacific Northwest and even what I'm seeing on the East Coast.

 

[nocfn]

I think the ladies prefer that you buy the larger profile oil cap . Equally impressive is a new seal for the power steering reservoir. I always change the expansion cap in whole, the bling is recognizable

 

[The Emperor]

The 500E Originality Police decree that original caps should be retained wherever possible, and only new rubber seals be used.

Failure to adhere will get you a force-choke from me or my apprentice, @clarkz71.

 

[gerryvz]

I think the ladies prefer that you buy the larger profile oil cap . Equally impressive is a new seal for the power steering reservoir. I always change the expansion cap in whole, the bling is recognizable

Perhaps you can get a new power steering reservoir cap knob for your fellow Texan, the guy in Prosper TX who just sold the 500E for $22K. His car REALLY needs a reservoir cap knob.

 

[nocfn]

Not being a lady myself, I hadn't noticed.

 

[gerryvz]

For those needing them, here are the part numbers for the rubber seals for the pertinent underhood caps:

Gas cap rubber seal: 140 471 00 79

Oil filler cap rubber seal: 102 018 03 80

Power steering reservoir cap rubber seal: 000 466 16 80

For the coolant expansion tank, you just have to get a new cap. The gaskets are not available separately.

For the Prosper, TX 500E seller, the part number for the power steering reservoir cap knob is: 000 466 03 68. MB list price $22.

 

[Ntrepid]

$11.50 for a gas cap rubber seal. Must be sold in lots of 10 so find 9 friends who need it or...,

...that is just the cost for a single $0.04 part :-(

There’s margin and then there is MARGIN!


Robert

 

[JC220]

$11.50 for a gas cap rubber seal. Must be sold in lots of 10 so find 9 friends who need it or...,

...that is just the cost for a single $0.04 part :-(

There’s margin and then there is MARGIN!


Robert

Or have 10 benzes that take the same rubber seal - just sayin!

 

[gerryvz]

One note: many of the aftermarket sites carry the Rein Automotive coolant expansion tank caps. These caps are actually OEM caps that have been repackaged in Rein packaging. They are made in Germany, and are less than one-half of the price of the factory MB caps with the star, but are otherwise identical.

I purchased three of these caps last year and replaced all of the caps on my vehicles with them. With the exception of the MB star, the Rein-packaged caps are identical in every way. This is one of the few Rein-reboxed parts that I would recommend purchasing, because it is essentially the factory part at significantly less cost.

Examples of these caps:

https://www.autohausaz.com/catalog/c/mercedes/1994/1195635-e500/16-cooling_system/2068-radiator_capexpansion_tank_cap?s=d&page=1

Mercedes-Benz E500 Expansion Tank Cap Parts | FCP Euro

Mercedes-Benz E500 Expansion Tank Cap parts online. Buy OEM & Genuine parts with a Lifetime Warranty, Free Shipping and Unlimited 365 Day Returns.

www.fcpeuro.com

 

[luckymike]

You can also buy bulk 3mm rubber sheet: US Black 152*152*3mm Square Rubber Sheet Chemical Resistance High Temperature | eBay to make your own seal. I did that and it's still holding several years later.

 

[gerryvz]

I guess it's a calculation for time and materials to purchase, vs. tacking $11.50 onto a parts order. This is one where I'd (personally) just BOGU it and get the factory part.

That said, I recently (as part of my Top-End Rebuild) did replace the rubber on the ETA cable clamp (where it clamps to the top of the intake manifold) with rubber from a Home Depot clamp of the same size. I bought a two-pack of the Home Depot clamps for $1.50, and remove the rubber from one clamp, removed the fossilized/cracked/flaking rubber from the MB clamp, and applied the Home Depot clamp rubber onto the MB clamp. Fit perfectly. Here are the Home Depot clamps (one without rubber is the one I cannibalized).

 

[gsxr]

Yeah, but is Home Depot rubber made in Germany?

New MB clamp was 000000-001045, rolled to 000-995-92-42, under $5 from MB at discount.

 

[nocfn]

When I refreshed the M117, I used heat shrink tubes on all of those to refrsh

 

[French02chris]

I know those posts are from last year....but I checked my cap today, and yep the seal is cracking!!!
SO I did order a new one!!! LOL