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Engine basics => Engine set up tips => Topic started by: Gary Anderson on August 05, 2009, 09:42:32 PM

Title: OS 46 LA or K&B 40
Post by: Gary Anderson on August 05, 2009, 09:42:32 PM
Hi guys,

Here is the question:

Which engine has the most power, runs the best, will last the longest etc. etc. I have both engines the OS 46 LA and both types of K&B 40's (Plain bearing and ball bearing) The K&B has a dyke's ring. The K&B doesn't start as easy as the OS 46 LA but once the starter touch the prop and spins the prop she fires and runs a real nice 4-2-4 or a hard 2, if you want her too. The OS 46 LA can be run many different ways also. I'm not sure how long a OS will stand up but mine has run for four years and still seems to be good, same with my old sweet heart the K&B. I have flown both engines in the same plane and I think the good old K&B has a little more in the tough spots. I would appreciate your opinion. Yes, you have to be able to play with each engine, rules rules Ha Ha, Gary
Title: Re: OS 46 LA or K&B 40
Post by: Martin Quartim on August 05, 2009, 11:49:58 PM
 I'd put a Bowman ring in your K&B engine and I'll bet your engine will start first flip and run much much better.


Martin
Title: Re: OS 46 LA or K&B 40
Post by: Greg L Bahrman on August 06, 2009, 12:39:53 AM
Are the weights equal??
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 06, 2009, 08:21:39 AM
Are the weights equal??
Hi Greg,

I don't have a digital scale, my K&B weighs right at 8 ounces, I believe the OS 46 weighs around 9.2 ounces.

Hi Martin,
Yes, I have Mr. Frank Bowman's ring in her. (Frank installed it a few years ago) Both engine are great, I would hate to have to my a choice of one over the other. The K&B is not made anymore but there is a lot of them around. Several years ago seemed like everyone had some of the K&B's hanging around. Gary
Title: Re: OS 46 LA or K&B 40
Post by: Jim Thomerson on August 06, 2009, 05:19:24 PM
I wasn't aware that K&B made a plain bearing 40.  Inquiring mind want to know.
Title: Re: OS 46 LA or K&B 40
Post by: Alan Hahn on August 06, 2009, 06:11:26 PM
I wasn't aware that K&B made a plain bearing 40.  Inquiring mind want to know.

Yes that is news to me too. The early K&B 40, the 8011 had a pinned thrust washer, and a pressed crankpin. The later 4011 had a machined crankpin, and either a collet or a D crankshaft (don't recall right now).

The last versions were ABC (don't recall those numbers). They included the Brodak version.

I don't recall any being plain bearing. That doesn't mean there wasn't one I am not aware of---of course.
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 06, 2009, 08:56:56 PM
Hi guys,
I'm sure I stated it wrong, so I'm sending a picture of two different type K&B Engines. The one I have in the plane seems to be mild compared to the one sitting on the wing. Both of these engines run very well, I also have a few that don't have lugs for a muffler, all I'm sure of, is that the K&B has been a good engine for me. They seem to like fuel but the one I have in my Tutor runs a little longer on the same tank. The OS 46 LA doesn't run quite as long as the K&B using the same plane and tank. The K&B I use on my plane called My Mess has a bigger venturi and it takes 6 1/2 ounces and you have to hurry to complete the pattern and yes the K&B on My Mess runs stronger. I guess the venturi makes a difference.

Gary
Title: Re: OS 46 LA or K&B 40
Post by: Balsa Butcher on August 07, 2009, 07:27:58 AM
Gary, checked out your pic.  Both engines have front bearings.  The one in the plane looks like a 4011, later versions had an ABC piston and sleeve and were sold be Brodak. The one on the tank looks like a Torpedo, an earlier hotter model with a smaller, lighter front bearing. 8)
Title: Re: OS 46 LA or K&B 40
Post by: Jim Thomerson on August 07, 2009, 10:40:55 AM
I really like the K&B 40's.  I have the impression from my experience that they run really well upright and inverted, but I was disappointed in them on two different profile airplanes.  On one of the profiles a Tower 40 ran as well as one could ask. 
Title: Re: OS 46 LA or K&B 40
Post by: don Burke on August 07, 2009, 11:55:47 AM
The engine on the plane is a "4011" 40, the other an "8011" 40.  They should be identical except for the front end assy. 
The difference is the bearings.  Both of yours have the same venturi boss bore.  There is an 8011 front end that has a smaller boss.  There are also early 40s and/or 35s that have an integral venturi, they were the first ones made for CL only.  The bosses with the removable feature were made when K&B got into R/C versions.  There is also a plain bearing version.  It is distinguished by a polished aluminum crankcase.  There are also muffler bolt hole versions, which yours are, and "wide by-pass" versions with no provision for muffler mounting.

As far as chooosing between the OS and the K&B, you pays your money and you takes your choice.
Title: Re: OS 46 LA or K&B 40
Post by: Jim Thomerson on August 08, 2009, 11:27:16 AM
I think the shiny case version you mention is the Series 75 35.  We used them in Midwest Sport Race.  A nice engine.
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 11, 2009, 02:04:05 PM
Hi guys,

Here's another old but goody, Gary
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 13, 2009, 03:06:39 PM
Hi guys,

Here's a couple more sweet babies. The Veco 61 and the K&B 61, not sure which one is the best, the Veco has a big prop shaft, where as the K&B has a 1/4" removable stud. They both will run at a low rpm, they both seem to have a small venture compared to the K&B C/L engine Mecoa sells. I'm not sure of the power but they both seemed to be pulling  pretty darn good on the test stand. Not many seem to want to play with these toys, most would rather play with the high dollar stuff which is great if you have the money. Being just a sport flier and a wannabe I'll just have to stick with my babies until I get pass the maybes. I wonder if Mr. Lee had anything to do with making my Veco, doesn't have his name on it but what I read, I believe he developed this baby, just having fun, Gary
Title: Re: OS 46 LA or K&B 40
Post by: Jim Thomerson on August 13, 2009, 05:23:39 PM
Some years ago, Tom Dixon did a review of the K&B 61. It is a one ounce heavier, slightly wider Super Tigre 61.  Same timing, same RPM on the same props.  I have a couple I have to build something for.
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 13, 2009, 05:52:08 PM
Some years ago, Tom Dixon did a review of the K&B 61. It is a one ounce heavier, slightly wider Super Tigre 61.  Same timing, same RPM on the same props.  I have a couple I have to build something for.
Hi Jim,

I really like both the K&B 40 and 61. Some say they're to heavy, my K&B 40 is lighter than my OS 46 and seems to pull the same size plane without a problem. I have Super Tigre 60 engines also, the K&B 61 seems to be a stronger engine than my stock ST 60. My brother has one of the K&B's that mecoa sells and the venturi seems to be a little larger than the venturi on mine. My brother's engine seems to run a little harder than mine but mine will run hard also.. I bench run the Veco 61 using a 14/5 prop and she just purred, I have a 13/5 on the K&B and got just about the same run. The Veco and K&B 61 will start with just a few flips bye hand. I guess I'm just a K&B kinda guy?? I'm kidding, I love them all, Gary
Title: Re: OS 46 LA or K&B 40
Post by: Bill Little on August 19, 2009, 09:00:31 AM
Hi Gary,

In its day, the K&B 40 was the cat's meow!  If I am not mistaken, Les used one in his Stiletto for the NATS and WC wins!  Stan Powell reworked them for *stunt* runs, retiming, etc..  I know the Stiletto in the AMA Museum has *K&B 40* on the cowl.

Papa Dave Hemstraught used the K&B 40s (from Stan) in his PT 19s for quite a while, eventually going to the higher tech engines.

I have one, retimed like Stan's, which I have never run, but always have wanted to. ;D

I do not have a lot of experience with the LA engines yet.  I think they are great for what they are.

Big Bear
Title: Re: OS 46 LA or K&B 40
Post by: Gary Anderson on August 29, 2009, 02:04:58 PM
Hi guys,

OS 46 LA, K&B 40 and the famous ST 46, which one is the best engine??? I believe most will state that the ST 46 is the best. I believe each engine can show off if used in the proper plane. The OS 46 is pretty cheap compared to the ST 46, which isn't made anymore but can be bought with real money. I don't believe the K&B 40 is being made, advertised on Mecoa but I don't believe he's made any to sell. There is a lot of K&B 40 that can be bought for not much money, so I believe its still a good engine for the money. So I guess if you compare each engine and cost, it would depend on how much you want to spend. I believe for the money the OS 46 LA's is one of the best deals going for wannabees, Gary