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Engine basics => Engine set up tips => Topic started by: Bootlegger on June 30, 2017, 08:05:44 AM

Title: tower 40
Post by: Bootlegger on June 30, 2017, 08:05:44 AM

  Guys, My Tower 40 seems to be "binding" or real "tight" when I run it.  It should have about two (2) hours of run time on it, or more.
 I am running an APC 11x4 prop with 5-10 % nitro and 22% oil, with a OS 762 muffler with the stinger removed and the exhaust opened up to .375 or more, however when I run a Scott Dinger tube muffler it doesn't seem to be as tight..

  Got any suggestions??  I am also running a T/Bolt long reach idle bar plug and a S/T knock off nva...
Title: Re: tower 40
Post by: Dan McEntee on June 30, 2017, 08:23:24 AM
   There should be quite a bit on the forum on this subject. The Tower .40 is a clone of the FP.40 but with much better fits and a true ABC construction. They tend to varnish up and get sticky. A friend of mine here in town had this very thing happen with his. You can tear it down and physically clean everything with some elbow grease, solvent and a scotch-brite. I think the problem area ion my friends engine was in the crank bearing area. Another thing you may want to try is to bench run it with a smaller prop, like a 9-5 or 9-4, and run it back in with some fuel with more synthetic or all synthetic oil in it, and run it at peak RPMS for a few tank fulls and see if it loosens up. It may not be running as hot with the Dinger muffler because it can breath a little better. Those 762 muffler were pretty restrictive and you just don't have it as open as the Dinger muffler. If you do the bench run method, I would do that without the muffler, just to give it a better chance of running a bit cooler, and less loaded down so all the crap can work it's way out..
   Type at you later,
   Dan McEntee
Title: Re: tower 40
Post by: RandySmith on June 30, 2017, 01:08:43 PM
  Guys, My Tower 40 seems to be "binding" or real "tight" when I run it.  It should have about two (2) hours of run time on it, or more.
 I am running an APC 11x4 prop with 5-10 % nitro and 22% oil, with a OS 762 muffler with the stinger removed and the exhaust opened up to .375 or more, however when I run a Scott Dinger tube muffler it doesn't seem to be as tight..

  Got any suggestions??  I am also running a T/Bolt long reach idle bar plug and a S/T knock off nva...

The Rods get stuck easy, and the cranks were  ultra tight in the motors, clean it, check the rod top bottom, and look close at the bushings, check to see if the crank is  tight, a tiny bit of sand or debris going into the intake  can galled a small line around the inside case bushing and lock the  crank tighter in the case
I have tons of parts for these

Randy
Title: Re: tower 40
Post by: M Spencer on June 30, 2017, 07:59:48 PM
Quote
I have tons of parts for these

Piston & Liners ??

Cheaper by the ton  VD~ S?P

Gudgeon & rod too .

Do these take circlips or the nylon pads ,

Thanks Randy .

Title: Re: tower 40
Post by: RandySmith on June 30, 2017, 11:17:07 PM
Piston & Liners ??

Cheaper by the ton  VD~ S?P

Gudgeon & rod too .

Do these take circlips or the nylon pads ,

Thanks Randy .

Rods    pins,  Venturies   NVAs,   Heads  ,  crankshafts, mufflers, a case or 2 , maybe  1 or 2  piston sleeves , bolt sets, drive washers, prop washers , prop nuts , or I will  use these  to make  whole motors  to sale,  I have  made and  sold  many dozens of these, and will still do so,  so I may not sale out of just the popular parts
and  yes  they rake teflon pads on the wrist pin ends

Randy
Title: Re: tower 40
Post by: Bootlegger on July 01, 2017, 06:25:34 PM

  Well today I got a chance to run the engine using 10% N and 22% all synthetic, it runs much better now, I got about 30min total on it today with a 10x4 prop running about 95-9800 R P M, next time will be an the model.

  Thanks for all the suggestions/help..