Join the C34 Association Today!
[C34 Home] [C34Tech Notes] [C34 Tech Wiki] [Join!]
Please login or register.
Advanced search  

News:

Pages: 1 2 3 [4]   Go Down

Author Topic: Propeller reconditioning  (Read 1173 times)

0 Members and 1 Guest are viewing this topic.

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 52
  • Posts: 6573
    • View Profile
Re: Propeller reconditioning
« Reply #45 on: January 21, 2019, 09:15:48 AM »

Noah : Unless Bob has "reengined", he should have a M25XP engine with a Hurth 50 Transmission.

A thought
Logged
Ron, Apache #788

Bobg

  • Forum - Petty Officer 1st Class
  • *****
  • Karma: 2
  • Posts: 372
    • View Profile
Re: Propeller reconditioning
« Reply #46 on: January 21, 2019, 10:18:07 AM »

Thanks Ron, yes I have the 25xp with the Hurth 50.  it is a 2;1 reduction, using a handheld laser  with reflecting tape on the crank pully and output shaft on the tranny, I read 50 RPM low at all speeds, i;e at 2000 rpm, I get 950 on the transmission shaft, never did check it before my prop re pitch, 50 rpm below half rpm probably not enough to reflect that much speed loss, can't turn the prop by hand while on the hard in gear, (one of the tests that was suggested to do on the tranny)
 just wondering if its a possibility that a over pitch prop can cause the transmission to start slipping.  Is it something to consider when re pitching prop?
Logged
Bob Gatz, 1988 catalina 34, Hull#818, "Ghostrider" sail lake superior Apostle Islands

Breakin Away

  • Forum - Petty Officer 1st Class
  • *****
  • Karma: 2
  • Posts: 291
    • View Profile
Re: Propeller reconditioning
« Reply #47 on: January 21, 2019, 10:32:18 AM »

My spec sheet says Hurth 50 is 2.05:1 ratio. If correct, that accounts for half your discrepancy.

Iím not an expert at this, but I canít imagine turning over the motor by turning the prop (especially at 2:1 nominal ratio) unless you have a compression release lever, and I donít think Universals have those, do they?
« Last Edit: January 21, 2019, 10:33:43 AM by Breakin Away »
Logged

2001 MkII Breakin' Away, #1535, TR/WK, M35BC, Mantus 35# (at Rock Hall Landing Marina)

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 52
  • Posts: 6573
    • View Profile
Re: Propeller reconditioning
« Reply #48 on: January 21, 2019, 02:43:53 PM »

Breaking : FYI, both the M25 & M25XP have compression release levers!!

A thought
Logged
Ron, Apache #788

Noah

  • Forum - Master Chief Petty Officer
  • *******
  • Karma: 19
  • Posts: 1352
    • View Profile
Re: Propeller reconditioning
« Reply #49 on: January 21, 2019, 03:00:54 PM »

Ronó curious did you or anyone  every successfully try to hand crank one?
Logged
1990 hull #1014, San Diego, CA,  Fin Keel,
Standard Rig

Ron Hill

  • Forum - Master Chief Petty Officer of the Navy
  • ********
  • Karma: 52
  • Posts: 6573
    • View Profile
Re: Propeller reconditioning
« Reply #50 on: January 22, 2019, 02:29:53 PM »

Noah : Don't know about the hand cranking, but I do know of someone that had a low battery start.

He hit the starter spinning the engine with compression release lever open and then closed it - causing the flywheel to continue to turn and it started the engine!!!
He's the same guy that showed me how to by pass the starter solenoid, by laying a long screwdriver shank on the threads of the starter  solenoid and then touching the engine block.  The starter immediately turns the engine over - don't leave the screwdriver on the block for more than a second!
 
He was an older gentleman ( had an early 1986 C34 M25) and was a line chief on B17s during WWII. 

A few thoughts
« Last Edit: January 22, 2019, 02:41:46 PM by Ron Hill »
Logged
Ron, Apache #788
Pages: 1 2 3 [4]   Go Up