|
|
06-04-2003, 09:12 AM | #11 |
RCC Apprentice
|
I'm no expert but it seems to me that if it waits till the second flight, something has to change by the second flight. Perhaps the engine is hotter (metal is expanded more)which shows up a problem. Unfortunately, I have no idea what that problem would be. Helpful eh?
__________________
Trees wreck planes!! |
. |
Sponsored Links - Subscribe to remove this ad. |
|
06-04-2003, 11:16 AM | #12 |
Guest
|
ok - I did flush the engine.
Temperature and humidity outside, no change I'm talking minutes between flights. The problem is not consistent with a 1/2 tank, 1/4 or 3/4 tank type thing. I'm still leaning towards the air leak. Is it possible that after the first flight the engine heats and cools and changes some gasket/metal differential and hence an air leak. If so where is that most likley... RD |
. |
06-04-2003, 11:33 AM | #13 |
RCC Supreme Contributor
I am: Andrew Coholic
Join Date: Sep 2002
Location: Timmins, Northern Ontario
Radio of choice:
JR 12X, 28X Feedback: 47 / 100%
Posts: 12,277
Total Props: 61
|
air leaking into the carb is the prime culprit - a leaky backplate, or even a head gasket/ glowplug gasket will NOT give the troubles you state.
__________________
Andrew Coholic -MAAC #26287L 1/2A to giant scale, IMAC, SAM, R/C sport, turbine jets, Heli's... if its got a wing or two and an engine - I like it! |
. |
|
|
06-04-2003, 03:13 PM | #14 |
RCC Supreme Contributor
I am: Jim McIntyre
Join Date: Aug 2002
Location: Claremont Ontario
Radio of choice:
JR/Spectrum # of RCs: 999
Feedback: 1 / 100%
Posts: 4,343
Total Props: 1
|
Really?
I'd be the first to admit that you probably know more about engines than I do Andrew but, a paper gasket is a well known cure to similar problems on the LA .15 (locally popular combat engine) in these parts. The theory (as I understand it) is inability to develop a reliable vacuum. I do agree that carb leaks are a common problem, typically related to carb seating, O-ring decay or needle valve 'trauma'. ---------------------- It's the presence of water that tweaks my curiosity. Consider that a small amount of water could accumulate in the muffler to be kept out of the engine while it's running by the simple fact that it is running... When the engine is shut down, there would be no flow to keep it from running back into the port.... : Then again, it may have something to do with the airspeed velocity of African swallows.
__________________
ScaleBuilder MAAC# 12719 6EQUJ5 WOW!! Si fractum non sit, noli id reficere - (If it ain't broke, don't fix it). |
. |
06-04-2003, 06:25 PM | #15 |
RCC Supreme Contributor
I am: Andrew Coholic
Join Date: Sep 2002
Location: Timmins, Northern Ontario
Radio of choice:
JR 12X, 28X Feedback: 47 / 100%
Posts: 12,277
Total Props: 61
|
Jim,
All I know Is I have run many engine with backplates that were tapped for pressure with nothing hooked up to them and they run fine. Sure there is some loss but it will not cause an engine to do funny things part way into a run. Same as a leaky head, its hard on the engine and messy but unless its bad enough to not run in the first place wont see that type of change. If you dont think an engine will run with a leaky backplate, take a beater, drill out a 1/16 or 3/32 hole in the back and see if it will run. I bet it will Now if there is a noticeable leak I take it forgranted that it should be fixed. Just wont cause the type of problem that the fellow is experiencing IMO... It would be MUCH easier if you could actually get the engine to run rather than "guess' at the cause.... ANyone near this guy??
__________________
Andrew Coholic -MAAC #26287L 1/2A to giant scale, IMAC, SAM, R/C sport, turbine jets, Heli's... if its got a wing or two and an engine - I like it! |
. |
06-04-2003, 08:26 PM | #17 |
RCC Supreme Contributor
I am: Andrew Coholic
Join Date: Sep 2002
Location: Timmins, Northern Ontario
Radio of choice:
JR 12X, 28X Feedback: 47 / 100%
Posts: 12,277
Total Props: 61
|
I was talking to my flying buddy Dan Nadeau this evening while we were flying about this... we also asked the same question - the engine is possibly 'over the hill"...
__________________
Andrew Coholic -MAAC #26287L 1/2A to giant scale, IMAC, SAM, R/C sport, turbine jets, Heli's... if its got a wing or two and an engine - I like it! |
. |
06-04-2003, 08:30 PM | #18 |
RCC Supreme Contributor
I am: Bob D.
Join Date: Aug 2002
Location: Whitby, Ontario
Radio of choice:
Futaba 12FG # of RCs: 1+
Feedback: 0 / 0%
Posts: 3,312
Total Props: 0
|
rdemy is part of the same club as Derrick, Jim Mc, Jim Moss, Fodder, Sholtz, H.I.P. and myself (and I'm sure a few others who remain anonymous ) . I'm sure if he brings it out, someone can assist.
(Hey, we have a lot of club members here eh? ) Bob
__________________
Bob D. Ajax RC Club Indoor Aero-Choppers Member of MAAC since I joined Lighten Up, Life is waaaaaayyyy too short |
. |
06-05-2003, 06:48 AM | #19 |
Guest
|
Wow - thanks for all the great ideas...
The engine is at least 5 years old and well used by me. So here's what I think I'm going to do. 1) Swap it for a newer .46 TT, I have. This will make the problem at the lake go away. 2) Have one of my club members look at the removed engine to see if it's a carb leak. I could take it apart, but unless the o-ring falls out in pieces I'd never know. Thanks everyone, I appreciated your advice... RD |
. |
07-03-2003, 06:57 PM | #20 |
Guest
|
PLEASE READ!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
sorry for posting this so late but..... i recently had an O.S 46 and to be brutally honest i have only had trouble with it. i know this TT 46 may not be any O.S but howerver i had the same problem as you my o.s 46 would conk out after giving it throttle now i know enough about engines to say this isnt any plug or high/low speed needle problem i would bet you a new set of bearings that the problem is directly related to your bearing some symptoms include.....
-loss of power - very hot to the touch after only minutes of flight and engine cut out after only minutes of running so the solution would be to take off your back plate and see if your back bearings are rusted that means they cannot have any dull looking surface on them then remove them if neccesarry and replace them with new ones. thats my bit of advice. i dont want to sound like im really smart or good with engines but i have had a problem axtremly close to the same as yours. and after all i am only 16! hahaha but the bet still remains (if you own the engine)! |
. |
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests) | |
Thread Tools | |
Display Modes | |
|