RunRyder RC
 3  Topic Subscribe
WATCH
 1 page 544 views POST REPLY
Scorpion Power ProModeler
HelicopterCentury Radikal G20-30 N640 Hawk Predator › Predator gasser pipe keeps getting loose
06-06-2010 11:43 AM  7 years agoPost 1
trillian

Veteran

London, UK

My Posts: All  Forum  Topic

What do you guys do to keep the pipe from coming loose on the gassers?

I have a Predator SE, 26cc Hanson engine and V3 pipe. I bought the heli 2nd hand and it was fine for quite a while but just recently the pipe vibrated loose in flight. I tightened it to what I thought should be very secure and yet it just keeps coming loose. (tried tightening while hot as well).

PM  EMAIL  GALLERY  Attn:RR
06-06-2010 03:15 PM  7 years agoPost 2
Billme

Elite Veteran

MS

My Posts: All  Forum  Topic

If its been running good, I would change the spark plug.. If that doesn't do it, check the fuel system, change the clunk, new line, clean screen in carb...
If you still having problem, most likely you are sucking air...If its not the insulator, it can be the head gasket, or rear seal under the magneto...

PM  EMAIL  GALLERY  Attn:RR
06-06-2010 07:18 PM  7 years agoPost 3
trillian

Veteran

London, UK

My Posts: All  Forum  Topic

Hi Bill,

So how do those things affect the exhaust pipe coming loose? Is it heat or something?

It seems to be running quite well as far as I can tell but I have not pulled the plug to check the colour.

PM  EMAIL  GALLERY  Attn:RR
06-06-2010 07:39 PM  7 years agoPost 4
Billme

Elite Veteran

MS

My Posts: All  Forum  Topic

Plug fouling changing the timing of the cycle... Air leaks such as head gaskets on the down stroke leaking can lean the mixture enough to cause hard hitting...

Or, you may not be putting the muffler on correctly and not noticng it till its real loose. This will cause the engine to hit hard and loosen the muffler, because it to can cause the engine to lean out, when back pressure changes.
I helicoil mine and face the muffler to get rid of the hi spots, then tightenn it up once after a run...
I use to have to put goop on the motor but since using the W motor, this is not a problem. Do the easy stuff first..

Leaks are the number one problem..Do not tolerate leaks, period..

PM  EMAIL  GALLERY  Attn:RR
06-06-2010 09:19 PM  7 years agoPost 5
trillian

Veteran

London, UK

My Posts: All  Forum  Topic

At the moment I have no reason to suspect an air leak really.

I have just removed the pipe and there is a gasket that looks like it needs replacing. It is unevenly smashed a bit and one end is considerably thinner than the other.

The thing is I bought this heli 2nd hand.

Yesterday was the first time I took it out since December. It seems to start easily and runs reliably and has plenty of power.

I think the pipe just rattled loose of it's own accord. I have no idea how tight it was to begin with and also it could be partly the jarring in transit and having not been run to full operating temp for some time until now.

The facing of the pipe and engine could do with a bit of sanding and I'll get a new gasket and then I suspect it should be fine.

It occurs to me also that nylon lock nuts might be able to fit behind the mounts on the engine (but perhaps the heat will melt the nylon bit ?).

PM  EMAIL  GALLERY  Attn:RR
06-07-2010 03:29 AM  7 years agoPost 6
Billme

Elite Veteran

MS

My Posts: All  Forum  Topic

If you run a gasket, the vario copper gasket is the only one that works..The stock gaskets have paper coated, and will compress, and allow the muffler to slowly work loose.. Copper doesn't compress as much and will last longer..Good luck

PM  EMAIL  GALLERY  Attn:RR
06-07-2010 05:00 PM  7 years agoPost 7
oldfart

rrProfessor

Vancouver, Canada

My Posts: All  Forum  Topic

Bill gives good advise re the gasket.

I have also uses aluminum ones in the past.

I have also found that once up to temp, a brief landing and a re-tightening of the bolts (now that all surfaces have expanded to what they are at operating temp) will insure a good secure attachment for a long time unless you run overly lean.

Phil

PM  EMAIL  GALLERY  Attn:RR
06-07-2010 05:52 PM  7 years agoPost 8
trillian

Veteran

London, UK

My Posts: All  Forum  Topic

Thanks for the input on this.

Do you think it's better to not use a gasket?

PM  EMAIL  GALLERY  Attn:RR
06-07-2010 10:57 PM  7 years agoPost 9
oldfart

rrProfessor

Vancouver, Canada

My Posts: All  Forum  Topic

I do not use any on mine which only results in a very insignificant blow by. But your mileage may vary, IMHO, it is well worth trying it without and then seeing what amount of blow-by you get.

Phil

PM  EMAIL  GALLERY  Attn:RR
WATCH
 1 page 544 views POST REPLY
Scorpion Power ProModeler
HelicopterCentury Radikal G20-30 N640 Hawk Predator › Predator gasser pipe keeps getting loose
 Print TOPIC  Make Suggestion 

 3  Topic Subscribe

Tuesday, August 22 - 10:21 am - Copyright © 2000-2017 RunRyder   EMAILEnable Cookies

Login Here
 New Subscriptions 
 Buddies Online