This is for a friend.


He has done a carb rebuild kit, and posted a picture of his diaphragm and gasket.

This is included below.

I noticed, there are some tan brown fibers.

And to me, I believe this may be coming from a felt clunk.

SO I asked him, are you using a Felt Clunk??

and he replied yes.

SO i can see now, that is a problem.


However, I use felt clunks.

I get mine all from Taildragger RC,
and I have opened up my carbs and never seen this before.

and this is with hundreds of flights.

SO my question to you all??

Which felt clunks are the bad ones to get?

Because I am sure you will have good ones and bad ones out there.

And, I would like to say, I swear by felt clunks. I love them.

Gets rid of burbles from long down lines, ,motor runs smooth throughout, and it will suck every last drop out of the tank.

I got one from northwest Rc and so far it's holding up. I have not taken apart the carb.

I was told only use walbro clunks and northwest said theirs are similar.

Originally Posted by Keith Cannon

I got one from northwest Rc and so far it's holding up. I have not taken apart the carb.

I was told only use walbro clunks and northwest said theirs are similar.

Yes, thank you so much Keith, that is the name of the brand,. I appreciate you

Yeah walbro is the little carbs on a lot of our gassers and power equipment like stihl. The local power equipment store should have them. The walbro felt clunks I got for a friend are for a Honda product and its in a honda bag but it says walbro on clunk.

Its a Honda part number 17672-ZOH-003

They seemed to work great in my buddies tank, stopped bubbles and drains tank and line dry before air hits carb as witnessed on test stand.

My ceramic clunk in the fiji tank I bought from wrongway rc functions just the same. You may consult them as well.

Go a little further for you here.

http://www.wrongwayrc.com/index.php?...product_id=213

http://www.ereplacementparts.com/fil...-p-559076.html

https://www.powerequipmentwarehouse.com/filter-fuel-17

Originally Posted by PremixMike

Yeah walbro is the little carbs on a lot of our gassers and power equipment like stihl. The local power equipment store should have them. The walbro felt clunks I got for a friend are for a Honda product and its in a honda bag but it says walbro on clunk.

Its a Honda part number 17672-ZOH-003

They seemed to work great in my buddies tank, stopped bubbles and drains tank and line dry before air hits carb as witnessed on test stand.

My ceramic clunk in the fiji tank I bought from wrongway rc functions just the same. You may consult them as well.

Go a little further for you here.

http://www.wrongwayrc.com/index.php?...product_id=213

http://www.ereplacementparts.com/fil...-p-559076.html

https://www.powerequipmentwarehouse.com/filter-fuel-17

could you give me your opinion on how the ceramic filters work compared to felt ones?

I have never used a ceramic filter, but like the idea of it, since it should not allow any particles to get to the carb.

Originally Posted by orthobird

could you give me your opinion on how the ceramic filters work compared to felt ones?

I have never used a ceramic filter, but like the idea of it, since it should not allow any particles to get to the carb.

Personally I think my ceramic clunk works great. It appears to be same clunk in my jersey modeler pump can as well. I hhavea little over 4 gallons through my dle35ra and no problems to speak of and less of a chance of fibers I guess.

My buddies fiji tank with strait through metal clunks was grabbing all kinds of bubbles at different rpms just sitting still on test stand. We used mine with ceramic clunk and no bubbles came down line and it sucks tank dry before air. Even to the extreme of shaking tank like a paint can with engine running, no bubbles.

The felt walbro replacement in my buddies tank acted the same way when shaking tank, no bubbles up line of running engine.

Not sure how the felt clunk reacts to reverse flow cleaning but my ceramic clunk had filtered 4 gallons and was showing a little color at the point of my sukhoi going down and the tank sat for several months in my storage shed and gas was bad and clunk looked dirty. I decided to pour dirty bad fuel from vent line then pump some fresh fuel in from the line that comes from ceramic clunk instead of fill line and it flushed the ceramic filter to bright white and new looking then I poured that gas out vent line and repeated for good measure.

Id say as long as you have one or the other and a 3 line tank youre doing the right thing for filtering the tank, stoping bubbles and not risking other points of air entry by running an inline filter or filler tee

Originally Posted by PremixMike

Personally I think my ceramic clunk works great. It appears to be same clunk in my jersey modeler pump can as well. I hhavea little over 4 gallons through my dle35ra and no problems to speak of and less of a chance of fibers I guess.

My buddies fiji tank with strait through metal clunks was grabbing all kinds of bubbles at different rpms just sitting still on test stand. We used mine with ceramic clunk and no bubbles came down line and it sucks tank dry before air. Even to the extreme of shaking tank like a paint can with engine running, no bubbles.

The felt walbro replacement in my buddies tank acted the same way when shaking tank, no bubbles up line of running engine.

Not sure how the felt clunk reacts to reverse flow cleaning but my ceramic clunk had filtered 4 gallons and was showing a little color at the point of my sukhoi going down and the tank sat for several months in my storage shed and gas was bad and clunk looked dirty. I decided to pour dirty bad fuel from vent line then pump some fresh fuel in from the line that comes from ceramic clunk instead of fill line and it flushed the ceramic filter to bright white and new looking then I poured that gas out vent line and repeated for good measure.

Id say as long as you have one or the other and a 3 line tank youre doing the right thing for filtering the tank, stoping bubbles and not risking other points of air entry by running an inline filter or filler tee

thank you so much for your excellent reply. Very good info there. Will research more on the ceramic clunks. Best regards, Cam

Originally Posted by orthobird

thank you so much for your excellent reply. Very good info there. Will research more on the ceramic clunks. Best regards, Cam

No problem. Glad to help.

Just ordered some of the ceramic filters. Thanks Mike! I let you know how they work out!

Can you give us a source?
I have had bad experiences with felt as well
The cheapie that came with the tank

Originally Posted by machzx

Can you give us a source?
I have had bad experiences with felt as well
The cheapie that came with the tank

http://www.wrongwayrc.com/index.php?...product_id=213

Just got done changing the felt clunk in my tank. Engine just refused to start one day. Had good spark so I decided to troubleshoot starting at the tank and working to the carb. Took the felt clunk off the clunk line and could barely blow through it. If you take the felt clunk apart, they are basically a felt plug clamped over a fine mesh screen. Very effective, but the felt portion of my clunk was rock hard. Didn't look dirty at all; just wouldn't pass fuel. Piss poor maintenance on my part as I skipped fuel tank overhaul on this plane since I hadn't flown it much last year. I'll be replacing it every year going forward and not being lazy.

I got a couple tanks from wrong way rc and they use fugi bottles with ceramic clunks and Viton line. I haven't had any issues yet.

^^ That there is about as bullet proof as you can get for a fuel tank installation

Just finished installing this.

Felt clunk is gone

Zip ties or steel wires are gone


ceramic clunk, Black Viton tubing, PSP cap, and tygon bands to compress the tubing to the nipples.