YS Header
 

Hi Guys,

My YS header keeps coming loose. I have tried different methods to try and stop it from loosening, but nothing has been completely effective.

Does any one else have this problem? Also, those of you that don't, what is the method you use to keep them tight?

Advice appreciated.

Regards
Scott

Tighten the header and then run the engine until it gets hot, re-tighten header while it's still hot. This has always worked for me.

Hi Scott,

On my gas engines' exhausts I use Loctite Ultra Copper high temp gasket maker. It has worked very well. But I don't know if it would work on the YS. Similar exhaust temps between the two types of engines. I would just add a thin layer to the nut, snug it down and let it cure for 24 hours.

Hi Matt and Russmall. I've tried both of these suggestions. It works for awhile, but it still eventually comes loose.

Thanks.

Are we talking about the bit that screws into the head or the two flanges that bolt together, or have you got the fancy one that tightens up with that big locking ring thingy?

For the usual Hatori type, I make sure the flange tightens up on the copper washer rather than binding up in the threads and bolt the two bits together with the supplied screws and graphite gasket. I've never used the fancy one??

Yeah it's the "fancy one" Brett. Lol.

The flange that screws into the head is fine. It's the big locking ring thingy that keeps coming loose.

I had to tighten it again yesterday, so I have logged the flight number and will see how many flights 'till it comes loose again. If I can get a consistent number of flights, I just may have check it before that number is up.
i suppose you could call it preventative maintenance.

drac:
I was wondering if you have the copper crush washer that goes between the header pipe and the head. This is the copper washer that absorbs the compression (much like the washer or an automobile spark plug) when the "nut" is tightened. I have found that if you do not use a washer or if you use an old washer then the header nut will loosen. I install a new copper crush washer, tighten everything down, run the engine, retighten when hot (tighten the nut IMMEDIATELY after engine shut down). I go thru three of these cycles and I have had hundreds of runs on my YS 140 and 160 without problems.

Ed

Hi Ed,

Which header are you using? I think it may be different to the one I have. Can you post a photo?

The YS header has a copper washer that goes between the flange and head, (I use 2 washers here). The flange is threaded and has a female taper, the header has a male taper that fits in and is held on by a single castellated aluminium nut. These tapers match perfectly and seal when tightened. It's the aluminium nut that comes loose, not the flange in the head.

How about drilling holes in the bolt head and safety wiring it?

It doesn't have a bolt.

Shame it's giving you trouble, they look really neat.

Yeah, it can be positioned any where and it's light.

I've always had the problem, but thought i'd ask here if anyone else has the same issue. Maybe it's the way I fit it, but there's only one way to do that.

Might just have to put up with it, work out how many flights I can do then tighten and tighten before every comp.

drac1

Brett and I have many hundreds of flights on multiple YS headers and have never had a issue with them breaking, coming loose ect.
They are by far the best lightest and user friendly header out there.
It`s a shame you are having issues with it. I suspect there is something wrong with the taper nut.
One thing though, if it has a split washer inside the female taper nut ,take it out.
I`ve seen some come with this and they jam/tighten prematurely and will not let you tighten them properly.

Bryan

Hi Bryan,

Thanks for the feed back. There is no split washer.

The mystery continues.

PS. How tight do you tighten the nut with the C spanner? Just by hand or tap it a bit?

drac

I use a 6" extender on the spanner wrench and bear down on it :)

Also ,YS has a new flange installer tool with three pins for the male side flange . On the single pin tool the lock pin will bend and distort the flange face and cause it not to seal correctly on the header face. Sometimes because of this, it will leak and not tighten correctly.
You can resurface it with some 400 wet sandpaper if that's the problem. I don't recommend the extender on the male flange to the engine because the washer takes care of the problem with keeping it tight and sealing the face.

I recommend getting the three pin installer it`s much better. Or drill and install your own pins like I did.

Bryan

They way I use the spanner wrench.

Hold the engine with one hand on the propeller shaft put the spanner parallel to the shaft and tighten the nut, try to use one hand to push the spanner and pull the shaft at the same time until you can't move it, this way I never got it to get loose. Also this method do not put any stress on the airframe, so even if you use a lot of force you won't break anything.

Regards

Alejandro

All the problems I had with the fancy aluminum ringy thingy Y.S. header were a thing in the past after gobbling up as many of the old style Hatori headers I could find. Since I've switched to electric, don't have much use for anything (pattern) glow.

Steve

Bingo!!!!!!!!!!!!!!!!!!!!!!!

Teflon tape...Wrap the threads with Teflon tape. You can find it in the plumbers section at your choice of Loews or Home Depot...

Sticking with glow. Don't want my house or car to burn down with lipo fires and only a 7 min run time.

Hi Steve,

Are you saying you had the same problem?

Hi Bryan,

It doesn't leak, just comes loose. I'll try your suggestions.

PM sent.

Hi Alejandro,

With the engine in the plane, I support under the prop shaft and tap the spanner with a small hammer. It seems to get plenty tight enough, so can't explain why it comes loose.

Tried that flycatch. Thanks.

Hi Mr Sheppard,

I've used hi temp silicon on the threads with no success. I have plenty of thread tape, so might try that.

Thanks.

Batteries are for driving servos. :).

drac:
I am using one of the headers here. Specifically I use # HAT 822:
http://www.centralhobbies.com/Exhaust/headers.html

After seeing your reply it appears as though we are using different units. Is your unit different than the one on the link above?

Ed

The only problem I have with YS is the lack of mufflers and headers for the larger engines. It seems like the only thing available is Hatori canisters or Pitts style wrap-around. Any suggestions? I've thought about having an adapter made to mate with the many gas engine mufflers.

I haven't come across anything else. Adapting a different muffler should be OK, but why wouldn't the Pitts style or canister work for you?

This is the YS header.

Scott,
This has always worked for me…
Wrap your muffler bolts in teflon plumbers tape,assemble the header but don't tighten the bolts fully.
Start the engine and warm it up
After it's pretty warm fully tighten the header bolts all the way and you should be good to go.

Hope this helps,
paul

Yessir. I don't recall the name of the manufacturer. A copper gasket onto an internal wrenching threaded male steel fitting through the header and iinstalled into the female threads of the aluminum motor head using a large allen wrench. An internal wrenching aluminum threaded cover was then installed on the header to seal the deal. Always tight when cool, gradually loosening when motor gets hot. Mine kept coming loose on my 140 Sport and 140L motors and after repeated attempts to tighten when hot, the wrenching forces exerted on the aluminum cover plate with the large allen wrench would ruin the cover plate. If not careful, could ruin the female threads on the motor head.

Whoa! I'm not familiar with that one!

The thread tape must be Teflon. I'm very surprised that no one else has chimed in to say it works and is the simplest solution. Just 3 or so wraps around the threads is all it takes. Good luck.

I didn't know there was any other type. PTFE is all I've used for 30+ years. Now that makes me sound old. Lol.

1 or 2 others have mentioned it.

Thanks all for the advice.

Drill and lockwire.

The first plane I put it on was a Aero-Works .90-1.20 Yak which was the only reasonable priced ARF that I could find in the correct weight range. The canister wouldn't fit and the Pitts requires the motor to be mounted inverted. I had to backset the firewall 1/2" to get the engine on a Hyde mount to fit in the cowl. I don't think I'm buying any more ARFs. I'll build my own to get the size and weight range I want, the color scheme I like, and it will be built stronger and more durable.

Mounting inverted is the easiest way to fit most engines. YS's don't have any issues being inverted. I fitted a DZ140 to a 65" Seagull Seafury ARF. The engine is mounted inverted on a Dubro soft mount with a Slimline Pitts muffler. Sounds great and runs perfectly.

I use the black high temp rtv gasket maker. I've found it VERY important to make sure there is NO trace of oil on the parts. I use a can of brake parts cleaner to degrease the parts. It's relatively cheap and it very convenient to use.

Ken

Hi Ken,

Silicon doesn't seem to work too well. I have taken Bryans advice and made an extension so to be able to get some more leverage. It's only had 27 flights since, but so far so good. When I get to 50, I'll start get hopefull.