W.P. Hurst

Bax, this is a FS120 Surpass that leaks fuel from the regulator and pump. Has been setting for some time. I have run 15% thru it and runs strong until I remove the hot shot from the glow plug. Ran about 30cc's of fuel and seems to leak more. Towers has the carb assembly and pump, but if I can avoid the cost repairing this one. Any hope?

cahusker

My Feedback: (50)

I have had some luck in stopping the regulator from leaking by replacing the cover with this one https://www.towerhobbies.com/cgi-bin...p?I=LXLYD5&P=Z
It seems like the older one warps and doesn't seal as well as it needs to and the newer one has an improved design that seems stronger and does the job.
Your results may differ though.

W.P. Hurst

Thanks, I'll try one.

W.P. Hurst

Well, I replaced the regulater cover and that stoppoed the leak. I also replaced the pump, it to was leaking, now as soon as I remove the glow starter it quits. Been adjusting and get a good idle, then quits as soon as the glow starter is removed. I would like to get it running good, but about to give up. Does anyone have some suggestions?

cahusker

My Feedback: (50)

Here are a couple of ideas to try. Look down into the carb opening with the throttle wide open and you should see the low speed needle sticking across the opening.There should be a slight gap where the smaller pin goes into the other side as you begin to close the throttle, about 1/16 of an inch. If that needs adjusting then turn the low speed needle until the gap looks that wide with the throttle wide open. Now set the high speed needle open 1.5 to 2 turns from fully closed. This should give you a good start point to begin tuning. If the engine is not pretty rich when you start it with these settings then something may be blocking the pump or regulator. Also if the engine does start and is in fact rich and still quits when the glow plug igniter is removed, you might want to change the glow plug for a new one. Hope this helps you, Lane

W.P. Hurst

Thanks, I'll give that a try in the morning. Will let you know. Thanks alot.

CHassan

My Feedback: (13)

Replace the plug?

W.P. Hurst

Yes, new os 4 stroke. Tried another to, no luck. It will idle rich for maybe a minute or less then sputters and wants to quit, Then I put the hot shot on and tweak a little more . When I get to lean with the low needle it will quit suddenly. Seems to have a very short window, even idling good it will still load up and quit. I tried the tee in the line from pump to carb with no luck. O-ring on the high needle valve looks good and the valves are really clean. Using cahusker's advice got it close, just can't find that sweet spot.

cahusker

My Feedback: (50)

One more thing to try. Start it and get it to full throttle, then open the high needle until it is really rich and let it run that way for a minute or two. Now close the high needle until you get max rpm's and just back off a click. If the engine will run steady at this high speed setting then start on the low speed needle and get it to where it will idle good and transition well..Sometime when these engines have been sitting for a long time the oil congeals in the needle areas and act like a blockage that just doesn't clear out at normal settings but does with the needle open wide.
If this doesn't work I would be willing to look at the engine for you if you were willing to send it to me, I'm 50+ years in the hobby and have repaired engines for many folks over the last 30+ years. Lane

W.P. Hurst

pm sent

W.P. Hurst

Sounds good to me. Sent you a couple pm's. Let me know, Thanks Bill

mvarzoni1

Hello hurst, I´ve got the very same engine as yours.
It ran Really well for 5 flights and than begun to leak on the Pressure regulator.
Did you have any luck on yours? Is it running in a reliable way?

thank you
Mauricio