1980 300SD - Simpler air filter? I can't keep my U-Tube attached - PeachParts Mercedes-Benz Forum

lombrozo · #1 09-24-2013, 12:37 PM

I have endless difficulty installing the U-Tube between the turbo and the stock air filter. I have replaced the rubber gaskets, but they tend to push down into the tube when trying to force it onto the turbo inlet and the air filter.

I would be perfectly happy to hose-clamp a K&N or equivalent filter onto the end of the turbo and be done with it. Any experience with this? Do I need to make an extension hose or size adapter to control temperature or provide a better fit?

I don't care about cold air, better breathing, or looking like a ricer Honda, just want to keep my engine alive forever.

The car is a 1980 300SD W116, 430,000 miles but I put in a used engine 50,000 ago.

Thanks for your ideas
David

sixto · #2 09-24-2013, 12:42 PM

Where did I put that flame suit?

You would be perfectly happy with a K&N or other open element air filter but the engine wouldn't be. Such filters are at odds with keeping your engine alive forever.

Use the money instead to buy a forum member a beer in exchange for showing you how to get the u-tube to stay in place.

Sixto
87 300D

mach4 · #3 09-24-2013, 01:23 PM

You could possibly use a variant of what I did on my Cali 617 project, which is outlined here - 380SL Diesel Conversion Project

On the Cali version the turbo sits higher so there may be more room. You'd need to just try it. I can definitely say that I love the ability to use standard Ford paper element filters, available anywhere for dirt cheap.

You may need to do something about the oil breather. I use a custom catch can on mine that ensures that the oil goes back to the sump and the clean vapor goes to the intake ahead of the turbo.

Zacharias · #4 09-24-2013, 02:39 PM

I had a '79 300sd, those U-shaped hoses are a bear when the material ages and gets stiff and deformed (sort of like me).

You said gasketS. You don't really need one at the air cleaner end, as I remember (I certainly never had one).

Boil up some water in a pan (or on a hot day, try leaving it in direct sun for a few hours). Either way, try to make the end that goes over the turbo inlet it more pliable.

Remove the round seal that isn't cooperating and put it aside, then work the end of the now-hopefully-pliable hose around the turbo inlet, to try to temporarily expand it a bit.

It's a huge PITA job but it can be done....

lombrozo · #5 09-24-2013, 06:52 PM

Do you put the rubber gasket in the turbo inlet and push the tube over it, or put it in the tube and try to work it over the turbo?

I cut a slit in the air filter sheet metal and crimped it a little smaller, that helped a lot, but how to get the turbo part properly assembled?

I agree with not WANTING a K&N filter, I have been following the hatred of those for a long time on a lot of forums.

I just want a reliable way to mount this tube. I will give boiling a shot, I had to do that to replace the under-the-intake manifold Idle Air Controller hose on a 190E the other day.

Zacharias · #6 09-24-2013, 06:57 PM

I could only make it work by putting the sealing ring inside the hose. You can also apply some oil on the turbo inlet tube to help things along.

The first time I had to do it, I was convinced the dealer had sold me the wrong sealing ring.

Maybe the hoses contract over time? I never had any problem on the air filter end, it slid right on (but I didn't put a sealing ring on that end either).

bricktron · #7 09-24-2013, 08:06 PM

i installed an airaid filter with a 2.5" ID flange. works great. i recommend against getting one of the oiled style of filters (like K&N), see if you can find a dry one instead. sixto, please elaborate on how this affects engine life.

sixto · #8 09-24-2013, 08:26 PM

You caught me. I'm a drone repeating what I read in this forum and others too often.

Sixto
87 300D

Simpler=Better · #9 09-24-2013, 10:20 PM

Quote:

Originally Posted by bricktron

i installed an airaid filter with a 2.5" ID flange. works great. i recommend against getting one of the oiled style of filters (like K&N), see if you can find a dry one instead. sixto, please elaborate on how this affects engine life.

Have a good read by the OCD oil guys:

Debunking the K&N Myth - Why OEM is Better : Nissan Articles

That being said, my 600cc bike runs 4x K&Ns and my 440cc runs 2x emgos because the stock airboxes took up too much space and the paper filters were a pain to find.

lombrozo · #10 09-25-2013, 05:26 PM

Just like K&N, they are proud of their world-beating quality. Do we believe they are different than K&N?
I only see one with a 2.5 inch throat - it is 5 3/8 dia at the base, tapering to 4 3/8, and 5 inches long. Is this the one you used?

Is the supplied hose clamp enough for reliable attachment, or do you think a bracket is needed as well?

Not looking for more power or more noise, just a filter that doesn't fall off!

Simpler=Better · #11 09-26-2013, 09:29 AM

The easiest by far is the #8038 paper filter, it's around $20. Combine that with a rubber coupler and a PVC elbow from your favorite hardware store and you're all set.

As seen on poleshady's car:

Or Torkey's setup:

compu_85 · #12 09-26-2013, 09:40 AM

That looks like a high quality filter - should keep out dirt a lot better than the oiled options.

-J

Simpler=Better · #13 09-26-2013, 11:08 AM

You will need to do something about the CCV-the cheapo option is to plumb it back into the pre-turbo pipe. An oil separator can be made by stuffing an large compressed air dryer with steel wool (there are pics around here somewhere)

pgringo · #14 09-26-2013, 08:47 PM

Step by step with parts list...

catch can & cold / hot air intake how to

Zacharias · #15 11-14-2013, 11:54 AM

I am starting to like this whole idea but would prefer to end up with a housing for the filter, a la Mach4's work on his diesel SL (pic attached from another thread).

Any ideas?