Page 1 of 2

Starting question

Posted: Thu Aug 23, 2012 10:49 pm
by seneca2e
I tried to start the Brantly today and it hit a few licks before we discovered a massive oil leak from the adapter plate oil seal where the fuel pump attaches. Oil would just drip from one of the fuel pump stud nuts. After we replace that we'll try again. I'm still concerned about twisting the tail rotor short shaft with my outer rotor blades off or wrinkling the blades with the blades on if I have a botched start. Even with the rotor brake on tight just a little surge made the main blades and tail rotor move a few inches on one attempt. I don't think it hurt anything but it really put me on edge. What would be wrong with just disconnecting the tail rotor shaft at the flex coupling behind the tranny and starting it like that(with the outer blades off as they are now)? Has anyone went that route or see anything wrong with that procedure?

Re: Starting question

Posted: Fri Aug 24, 2012 9:48 pm
by 9121u
HI yes that is a good way to run it .and you can also check your balance this way for your in board blades also if your blades try to turn with rotor brake on tight at idle.means your centrifugal clutch spring probably needs to be greased this needs to be done every 300 hrs.. or clutch plates are warped.you still have to be careful on run up speeds.. lycoming engines like some type of load on them.. its just like a airplane engine.not supposed to run with out a prop

Re: Starting question

Posted: Sat Aug 25, 2012 5:21 pm
by Randy Strock
Hey Tom......would you please expound a little bit about your comment that "you can check your balance this way" ? trying to figure out what you meant. thanks Randy

Re: Starting question

Posted: Sat Aug 25, 2012 8:06 pm
by 9121u
HI RANDY good that you said that.. I thought abought it after I posted it.. hear goes.. you can not balance any thing at this point its a... check.. to get the balance better later on and saves time.the in boards should be very smooth at this point.and if not then there's a problem with the bearings or out of phase or other components have been changed that wear not equal in weight. and also after the thrust bearings have been greased good time to grease this now. this gets read of the extra grease. it will get slung out the vent hole.. because if the grease is not.. equal.. this will cause a imbalance problem later when you install outer blades and now all has to be done is to balance the main blades to inboard.all the weights have to be removed all so just need to take note where they were located.IF this all goes good then hook the tail rotor back up and check its balance.but that another story.you have to be very careful doing this.if the person doing is not.. experienced.. can cause some serious hidden damage to drive components and not no it..... BILL or RON . chime in on this.. its very hard to tell some one how to do something with showing.I can only offer advice on what to check and look for and not to tell any one how to repair... the way it should be..hopes this helps.....tom

Re: Starting question

Posted: Sat Aug 25, 2012 9:38 pm
by seneca2e
What concerns me is the long period this machine has sat between starts. Still thinking it might be worth the trouble to disconnect the tail rotor shaft to guard against a problem on the next start attempt. It shouldn't be a problem if I keep the rotor brake tight and watch the fuel prime but still the components on this helicopter are very rare and expensive so I want to get this right :-)

Re: Starting question

Posted: Sun Aug 26, 2012 6:59 am
by 9121u
HI yes I would disconnect the drive shaft at the MR gear box you will be OK then. just run her up slow on RPMS to 2000 that's all i have ever done. should be fine....just glad to here your getting back in the air...let us no how you made out. also now would be a good time to bleed out oil pressure line at the gage. brantlys are known for the oil pressure to come up slow because of air in the line.tom

Re: Starting question

Posted: Tue Aug 28, 2012 11:13 pm
by seneca2e
I got it started today!! Outer blades off so I used extreme care. Decided to do a sprag clutch check and split the needles. I immediately thought maybe that wasn't a good idea with the outer blades off. No harm seems to have ensued though. I really can't believe I let it set for over two years after I bought it. I guess other projects kept relegating it to the back of the hangar. Next comes mounting the outer blades and well you know what comes after that!!!!!!!!!!!!

Re: Starting question

Posted: Wed Aug 29, 2012 4:28 am
by Ron Spiker
Best of luck with getting it back in the air again. Sounds like you are quite excited about it, and we are for you, too. Keep us posted how it goes.

Re: Starting question

Posted: Wed Aug 29, 2012 6:37 pm
by seneca2e
Thanks Ron. It's been a long time coming. Probably going to have some more maintenance isssues-I'm expecting it-but just getting the thing rotating at least gives me a slight tailwind lol.

Re: Starting question

Posted: Sun Sep 02, 2012 12:44 pm
by seneca2e
Ran it for the second time. Had a engine tach cable shear(should have pulled and lubed it before I ran it). Got a small leak at #1 cylinder exhaust-it had 3 no blow thick spiral gaskets on the other cylinders and the thin sheet metal ones you use in pairs on #1. Cylinder exhaust port surface still looked really good so it gets a thick exhaust gasket(as well as #3 since I had to loosen it to get #1 off). One of the exhaust studs turned out with the nut so I'll replace that with an oversize one and some red locktite. Hopefully Gary will have the tach cable and a few seals I need. My manifold pressure didn't come up much even with it at 2800rpm but running it with the blades off and the collective down this could be normal. The gauge appears almost new and goes to ambient pressure(29 inches or so) at shutdown and down to 12 inches when it's running so that should be about right. When I get to raise the collective hopefuly the MP should indicate more. Only other thing was a defective hobbs meter(checked oil pressure switch which was fine) but that is a cheap, easy replacement.

Stlil not sure what I should put in the ldg gear oleo struts. Supposed to have red 5606 but someone put in oil of an undetermined weight-I've seen this done before on aircraft since 5606 is thin as water and leaks easily. Has anyone used oil vrs the hydraulic fluid(5606)? If so what kind and weight? Just wonder about the dampening effect-I assume it'd make it a bit stiffer.

Re: Starting question

Posted: Sun Sep 02, 2012 3:05 pm
by Ron Spiker
Each tach cable has to be custom made. I suggest going to a motorcycle shop with the length and type of ends you need and have them make you one.

Re: Starting questionlanding gear oil

Posted: Mon Sep 03, 2012 8:50 am
by fixnfly
Use 5606 in the gear, If it leaks out rebuild the strut, done correctly it shouldn't leak.

Re: Starting question

Posted: Mon Sep 03, 2012 12:34 pm
by 9121u
HI bill thanks for reply .where do you buy the oil at.do they sell this type at parts store....thanks tom

Re: Starting question

Posted: Mon Sep 03, 2012 5:22 pm
by seneca2e
Thanks for the replys. Tom you can get 5606 hydraulic fluid from Aircraft Spruce for about $5 per quart. Most all FBO's have it in stock as well as it is widely used in all GA aircraft brakes and most retractable gear hydraulic systems. I buy mine from Aviall or Spruce usually.

Re: Starting question

Posted: Sat Sep 08, 2012 11:36 pm
by seneca2e
Well I got the exhaust back on today with a couple no blow gaskets installed on #1 and #3 with just a thin smattering of Copper RTV(good to 700 degrees intermittent). I normally don't use it but some of the more notable experienced mechanics in the industry have taken a stand in favor of using it so I thought I'd try it sparingly. It is NOT going to seal up a badly eroded cylinder flange but could help seal some small irregularities between the no blow gasket, cylinder head, and exhaust pipe flange. I replaced one exhaust stud and used new nuts and washers and all seems fine there now.

The engine tach cable proved a different story. Turned out the inner cable apparently left some balled up material in the cable sheath so no joy on just replacing the inner core wire. Removed the whole cable-it measured 91 and 1/2 inches long from end of ferrule to end of ferrule. When I pieced the inner cable together it measured 93 1/4. Aircraft Spruce sells made to order cables and depending on how many bends you have the inner cable shortens(11/16 inch per each 360 degree bend supposedly). Tricky deal replacing a mundane cable. I'll order a new one Monday and hope it fits correctly. Pulled the even longer inner cable out of the rotor tach and cleaned it and relubed with Mobile SHC 100 synthetic wheel bearing grease which has a super wide temperature range. Don't lube the last few inches before the instrument and make sure you get the correct Lay cable. Althought A/C Spruce says most standard instruments take left lay cables(which is a counter clockwise drive shaft at tach drive socket as you look at it straight on) it sure appears as though the Brantly will take a right lay cable as it has a clockwise rotation as you look straight on). If you get the wrong lay cable they'll unwind over time and you'll be fixing it again before you know it.