News:


  • May 05, 2024, 02:47:32 AM

Login with username, password and session length

« previous next »
Pages: [1]   Go Down

Author Topic: OS20FP crank bearings?  (Read 4711 times)

Offline James Holford

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1515
OS20FP crank bearings?
« on: January 22, 2017, 06:55:04 PM »
Might be getting a OS20FP but low and behold the guy says it needs crank bearings as its really loose by the prop washer judging by the video he sent me.

 Is it worth to get and fix? Costly fix?  Only engine itself only gona run me $20 bucks.

Ideas?

Sent from my SAMSUNG-SM-G891A using Tapatalk
Logged
Jamie Holford
Baton Rouge Bi-Liners
Lafayette, La
AMA #1126767

Offline Reptoid

  • Trade Count: (0)
  • Captain
  • *****
  • Posts: 437
Re: OS20FP crank bearings?
« Reply #1 on: January 22, 2017, 09:10:52 PM »
The 20 FP is a bushing crank engine (no Ball bearings) Case has an integral non-replaceable bushing that the crank runs in.
Logged
Regards,
       Don
       AMA # 3882

Offline Dan McEntee

  • 23 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 6879
Re: OS20FP crank bearings?
« Reply #2 on: January 22, 2017, 09:27:57 PM »
  Describe loose? Does it go in and out or up and down? If it's in and out, that is normal end play and is necessary. If it's up and down, and not too bad, just put a little more oil in your fuel. For twenty bucks it's worth the gamble. And you could always keep your eye open for a parts engine with a good case.
   Type at you later,
     Dan
Logged
AMA 28784
EAA  1038824
AMA 480405 (American Motorcyclist Association)

Offline James Holford

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1515
Re: Re: OS20FP crank bearings?
« Reply #3 on: January 23, 2017, 03:57:28 AM »
Quote from: Dan McEntee on January 22, 2017, 09:27:57 PM
  Describe loose? Does it go in and out or up and down? If it's in and out, that is normal end play and is necessary. If it's up and down, and not too bad, just put a little more oil in your fuel. For twenty bucks it's worth the gamble. And you could always keep your eye open for a parts engine with a good case.
   Type at you later,
     Dan
In and out

Sent from my SAMSUNG-SM-G891A using Tapatalk

Logged
Jamie Holford
Baton Rouge Bi-Liners
Lafayette, La
AMA #1126767

Offline James Holford

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1515
Re: OS20FP crank bearings?
« Reply #4 on: January 23, 2017, 04:32:55 AM »
Video he sent me of it




Sent from my SAMSUNG-SM-G891A using Tapatalk

Logged
Jamie Holford
Baton Rouge Bi-Liners
Lafayette, La
AMA #1126767

Offline Motorman

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 3267
Re: OS20FP crank bearings?
« Reply #5 on: January 23, 2017, 06:45:14 AM »
blank
« Last Edit: March 06, 2022, 04:09:11 PM by Motorman »
Logged

Offline Mike Bufkin

  • 2017
  • Trade Count: (0)
  • Lieutenant
  • *
  • Posts: 79
Re: OS20FP crank bearings?
« Reply #6 on: January 23, 2017, 12:58:57 PM »
Yep,thats normal,it's even the ABN one,if it has the right muffler I'd definately buy it.
E-2030 muffler I think
Mike
Logged

Offline Tim Wescott

  • 2016 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 12813
Re: OS20FP crank bearings?
« Reply #7 on: January 23, 2017, 02:41:45 PM »
Quote from: Reptoid on January 22, 2017, 09:10:52 PM
The 20 FP is a bushing crank engine (no Ball bearings) Case has an integral non-replaceable bushing that the crank runs in.

Which an accomplished machinist might replace on a bet, but which isn't a cost-effective repair given all the engines on eBay.  Save it for 50 years; then it'll be a Valuable Antique and someone who isn't born yet will do the job just to have their very own running example.
Logged
AMA 64232

The problem with electric is that once you get the smoke generator and sound system installed, the plane is too heavy.

Offline James Holford

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1515
Re:
« Reply #8 on: January 23, 2017, 02:51:52 PM »
I used to have a 20fp on a 6ft Telemaster that would start on the first flip everytime no matter how hot or cold... think Dane Martin has it now.


 I don't really need this engine as I now have a nice assortment of .25s . But hey another engine can't hurt.. may make good trade bait ;)

Sent from my SAMSUNG-SM-G891A using Tapatalk

Logged
Jamie Holford
Baton Rouge Bi-Liners
Lafayette, La
AMA #1126767

Offline Air Ministry .

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 5004
Re: OS20FP crank bearings?
« Reply #9 on: January 23, 2017, 04:12:18 PM »
Some people whine that the 20s better than the 25 . AND the guts are transferable - either way .

As it hasnt got a prop to lock the drive washer , half the slacks the prop driver loose .  LL~

looks like theyres another two hiding behind it . Ive got a couple of butchered for classic B T/R cases  spare . Wouldnt take a muffler unless it was custom curved in as the stacks are gone .
Logged

Offline James Holford

  • 2020 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1515
Re:
« Reply #10 on: January 23, 2017, 04:15:50 PM »
I wouldn't use the muffler anyways:)

Sent from my SAMSUNG-SM-G891A using Tapatalk

Logged
Jamie Holford
Baton Rouge Bi-Liners
Lafayette, La
AMA #1126767

Offline Robert Zambelli

  • 23 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2927
Re: OS20FP crank bearings?
« Reply #11 on: January 24, 2017, 05:39:05 PM »
For what it's worth, I've re-bushed quite a few engines with excellent results.
I make the bushings from a special manganese bronze alloy, which is formulated for high speed sliding motion.

Here are a few photos but I can publish the entire article if anyone is interested.

  Bob Z.
Logged

Offline Russell Shaffer

  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1333
Re: OS20FP crank bearings?
« Reply #12 on: January 24, 2017, 09:26:55 PM »
That's nice work, Bob.
Logged
Russell Shaffer
Klamath Falls, Oregon
Just North of the California border

Offline Robert Zambelli

  • 23 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2927
Re: OS20FP crank bearings?
« Reply #13 on: January 25, 2017, 08:29:05 PM »
Thank you, Russ.

Most of the mods I've done have been McCoy and Fox.
When I do McCoys, I also polish the crankshaft but before polishing, I put a .010 deep oil groove opposite the intake port and 3/16 inch from the front.

   Bob Z.
Logged

Offline Phil Krankowski

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1031
Re: OS20FP crank bearings?
« Reply #14 on: January 25, 2017, 09:37:15 PM »
Is that pinned or otherwise indexed, or just a press/shrink fit?

Phil
Logged

Offline Robert Zambelli

  • 23 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2927
Re: OS20FP crank bearings?
« Reply #15 on: January 26, 2017, 01:16:50 PM »
Hi, Phil.
I machine the parts for a line-to-line fit.
Then, I freeze the bushing and heat the case to around 350.
It usually slips right in.
Next step is to bore the intake port.
Finally, bore to accept the crank.
Logged

Offline Russell Shaffer

  • AMA Member
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 1333
Re: OS20FP crank bearings?
« Reply #16 on: January 26, 2017, 01:47:42 PM »
And, if you went into business and charged even a nominal sum for your hourly rate, you could buy several new engines for one bushing.  A fun job if you do it for yourself, though. 
Logged
Russell Shaffer
Klamath Falls, Oregon
Just North of the California border

Offline Phil Krankowski

  • Trade Count: (0)
  • Admiral
  • ******
  • Posts: 1031
Re: OS20FP crank bearings?
« Reply #17 on: January 26, 2017, 06:23:43 PM »
Thank you Robert.  That is a straightforward process.

Phil
Logged

Offline phil c

  • 21 supporter
  • Trade Count: (0)
  • Admiral
  • *
  • Posts: 2480
Re: OS20FP crank bearings?
« Reply #18 on: January 27, 2017, 09:31:16 AM »
For $20     if it runs well, that's a good price.  Even if you have to eventually replace the piston/liner the cost is still reasonable for what is a very good engine.
The end play is nothing as long as the crank doesn't visibly rock while running.  That makes lot of noise and erratic running that even extra oil won't fix.

OS made the FP's very well for the price.  Kept clean with adequate oil they run a very long time.

IF you already have the needed machines and tooling or a buddy willing to donate the time to do it, as Bob Z. says, it's pretty straight forward.  Figure a day for someone doing it that knows what they're doing.
Logged
phil Cartier

Advertise Here
Pages: [1]   Go Up
« previous next »
Tags:
 


Advertise Here