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Air filter foam for carb intake hose???

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I've heard of some DR's sucking in enough dirt and grit through the carb intake hose to ruin the motor. The little plastic "breather/dust settler" on the hose seems to need some filter material. Has anyone ever used something like an oiled filter inside of the "breather"? I'm about to take a piece of small engine air filter foam and insert it into the "breather". Give me your thoughts on this....

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What are you talking about?:applause: The engine breather?

I think he's refering to the carb diaphragm vent hose with it's little filter lying on top of the air box by the snorkel. Yeah, the Sarge had engine failure from sand making it's way into his engine through that filter/breather.

http://www.unifilter.com/online%20catalog/accessories.html Uni Breathers down the page a bit might be a good answer to the problem.

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I think he's refering to the carb diaphragm vent hose with it's little filter lyinh on top of the air box by the snorkel. Yeah, the Sarge had engine failure from sand making it's way into his engine through that filter/breather.

http://www.unifilter.com/online%20catalog/accessories.html Uni Breathers down the page a bit might be a good answer to the problem.

Yep.......it's the carb vent hose filter/breather. I think a piece of oiled foam cut to fit and inserted into the opening will do the trick. If the foam works for Briggs and Stratton it will work fine for this application. I don't want Mr. Sandman to visit my DR!

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Yes, this little filter was the cause of getting a new topend on my bike. :lol: That thing sucks for any riding except street only!!

What I did was take a filter foam for a lawnmower and cut it to fill the cartridge up the rest of the way to the top and squirt it full of hightack filter oil.:applause:

Ive had it in some very dusty conditions since, and its working out good .you can take (the chunk) of filter out with needle nose plyers and wash/reoil it very easily.. Also Ive had my diaphram cover off to check inside and its still shiney and new lookig in there.

This filter must of been an oversight on Suz's part, I mean come on these bikes do go in the dirt. And that thing does have suction on it.

Oh well, lesson learned the hard way by me. Maybe having this info on TT will save someone the problem I had..:applause:

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Rob -

> I think he's refering to the carb diaphragm vent hose with it's little filter

> lying on top of the air box by the snorkel.

Isn't that the float bowl vent hose? Could sand get sucked into the engine through the vacuum chamber diaphragm hose?

Just curious.

Rick

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Float bowl vent hose? Is there such a thing on a DR? :scratch: Not on mine...

(he was referring to the diaphragm vent hose)

And the only way dust can get into the engine is through the small hole in the carb slide. The fact that Suzuki decided to place an air filter on that vent line proves to me that dust indeed can get into the engine through this hose.

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Yep.......it's the carb vent hose filter/breather. I think a piece of oiled foam cut to fit and inserted into the opening will do the trick. If the foam works for Briggs and Stratton it will work fine for this application. I don't want Mr. Sandman to visit my DR!

That's what I did, but I think this big hose is the crankcase breather.

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That's what I did, but I think this big hose is the crankcase breather.

Nope, the crankcase breather hose connects at the back of the transmission then travels up under the tank and back down to the air box. That extra trip up under the tank is to allow any oil mist that might get drawn up to drain back into the tranny. The diaphragm vent hose connects to the non-vacuum side of the diaphragm housing. Even through it is on the non vacuum side of the diaphram, leakage past the slide in the slide track can suck a slight amount through this hose. Plus its design is to allow a place for the displaced volume on the non-vacuum side of the diaphram a place to go. Basically this vent is breathing in as you open the throttle and out as you close the throttle. So, the bottom line is: hell yes there should be a good filter on this line! :applause:

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Max -

> Float bowl vent hose? Is there such a thing on a DR? :scratch: Not on

> mine...

Two vent hoses come off the carburetor. One comes off the diaphragm cover on top. It has no filter. The other comes off the right side of the carb and has a filter.

The diaphragm moves up and down with the slide. It is not clear to me how sand could get sucked into the engine through the diaphragm vent hose and past the diaphragm.

> (he was referring to the diaphragm vent hose)

That is why I asked the question.

> And the only way dust can get into the engine is through the small hole in

> the carb slide. The fact that Suzuki decided to place an air filter on that

> vent line proves to me that dust indeed can get into the engine through

> this hose.

If the vent hose with filter is a float bowl vent hose, sand could indeed get sucked into the engine if sand found its way into fuel in the float bowl.

Rick

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Max -

> Float bowl vent hose? Is there such a thing on a DR? :scratch: Not on

> mine...

Sure there is... its the hose the comes off the carb body just below the diaphram vent hose or Carb Air Hose as they call it in the manual. Without a float bowl vent there would be no place for the displaced air to go as the float bowl fills.

Two vent hoses come off the carburetor. One comes off the diaphragm cover on top. It has no filter.

That is your vacuum petcock hose.

The other comes off the right side of the carb and has a filter.

The diaphragm moves up and down with the slide. It is not clear to me how sand could get sucked into the engine through the diaphragm vent hose and past the diaphragm.

Because there is clearance between the slide and the track that the slide travels up and down in.

> And the only way dust can get into the engine is through the small hole in

> the carb slide. The fact that Suzuki decided to place an air filter on that

> vent line proves to me that dust indeed can get into the engine through

> this hose.

Getting dirt on the top side of the diaphragm to be sucked down through the vacuum ports would be a real feat....

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Rob -

I wrote:

>> Two vent hoses come off the carburetor. One comes off the diaphragm

>> cover on top. It has no filter...

You wrote:

> That is your vacuum petcock hose...

I write: Oops. You're right. Forgot about that. Thank you.

Rick

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Sure there is... its the hose the comes off the carb body just below the diaphram vent hose or Carb Air Hose as they call it in the manual. Without a float bowl vent there would be no place for the displaced air to go as the float bowl fills.

Yeah, makes sense. Sorry

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Has anyone found a replacement filter similar to the one mentioned in this article?

filter_comparo-250x187.jpg

Bottom of the page - http://www.topgunmotorcycles.com/techinsight.html

If I was in the US I would buy one from the author's but I figure it would be more practical to track something down locally?

Hey Burren,

Any place that sells Uni filters should have those. I just picked one up from a local Cycle Gear store this weekend. Here is the link to Uni's website that lists the filter.

http://www.unifilter.com/online%20catalog/accessories.html

Hope this helps!

John

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Do not know what one to get Clamp-on type or push-in type what size did you get :D SIZE: 3/8” or SIZE: 5/8” or SIZE: 1/2” or SIZE: 5/16” :D:D:busted::banghead:

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Do not know what one to get Clamp-on type or push-in type what size did you get :D SIZE: 3/8” or SIZE: 5/8” or SIZE: 1/2” or SIZE: 5/16” :D:D :D :banghead:

Push in type for a 1/2 hose I believe. Mine actaully measures about .61 in OD not including the barb flange.

You can just buy one here: http://www.multisurfacemotorcycling.com/products/drprod.htm

That way you know you'll be getting the correct one... besides they have other cool stuff to look at. :busted:

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I had a little K&N laying around,the breather hose fits on it tight.When I first got the bike and seen that,it just didn't look right.

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