HarleyTechTalk

Technical Forums => General => Topic started by: motorhogman on February 03, 2020, 06:45:55 AM

Title: Cam support plates "B" vs A motors..
Post by: motorhogman on February 03, 2020, 06:45:55 AM
https://www.youtube.com/watch?v=HbOuoQbPwzo


Could somebody smarter than me take a peek at this video from the 4 minute mark to about 4 min and 30 seconds.

Is he correct in saying that plate with the oil passage is for a B motor..

I have my oem plate and one that was replaced under warranty years ago.. Both have that oil passage. My bike is a 2001 FLHT..

My oil pressure is great..

OK.. I just figured out why that port does't matter.. The port it would feed in the case is blocked.. 

I decided to post this even though I figured out what the answer was.  maybe somebody else will learn from it ..
Title: Re: Cam support plates "B" vs A motors..
Post by: les on February 03, 2020, 07:15:20 AM
One check that can be done is to go to an online parts finder and cross check part numbers between the A and the B engines.
Title: Re: Cam support plates "B" vs A motors..
Post by: motorhogman on February 03, 2020, 07:48:57 AM
Quote from: les on February 03, 2020, 07:15:20 AM
One check that can be done is to go to an online parts finder and cross check part numbers between the A and the B engines.

Good idea Les.

I checked and found the SoftTail and the FLHT use the same cam plate (25284-11) for 2001 anyway.  Guess the engine passage was blocked on that year ( maybe others to)   to facilitate the use of one plate PN.. 

One thing i noticed different is the small oil hole for oiling the cams is relocated from between the cams on my original plate to above the rear cam on the one the dealer replaced under warranty.
Title: Re: Cam support plates "B" vs A motors..
Post by: MikeL on February 03, 2020, 07:56:55 AM
Same part numbers 25284-11 2002 model years A&B
I have never had an oil pressure problem. I'm sure I have mixed and matched cam plates between A&B engines.


                                                                                               MIKE



Title: Re: Cam support plates "B" vs A motors..
Post by: motorhogman on February 03, 2020, 08:06:36 AM
Quote from: MIKEL on February 03, 2020, 07:56:55 AM
Same part numbers 25284-11 2002 model years A&B
I have never had an oil pressure problem. I'm sure I have mixed and matched cam plates between A&B engines.


                                                                                               MIKE

Yea.. I suspect that the case oil passage for the balancers is blocked on Touring models.  Just watching that video made me  :scratch:..
Title: Re: Cam support plates "B" vs A motors..
Post by: Boe Cole on February 03, 2020, 09:42:57 AM
Over the years I've run into similar issues where a manufacturer will have a common part (carburetors mostly) with passages that do not have a corresponding passage in the engine.
Title: Re: Cam support plates "B" vs A motors..
Post by: motorhogman on February 03, 2020, 10:31:12 AM
Yes.  I have noticed that quite often on small engine carbs. lawn tractors, string mowers, generators, and chain saws..   thanx to the crap we have for gas today I've had several occasions to observe this. 
Title: Re: Cam support plates "B" vs A motors..
Post by: Scotty on February 03, 2020, 10:41:02 AM
Early twin cam (1999 models) motors did not have the boss and they used to supply a bolt to block that hole on the new 2000 up cam plates otherwise oil would blow out everywhere and no pressure.
For the 2000 model year they included the blank boss for A motors so they could use the same cam plate in A & B motors.
So unless you have a 99 A motor you would never know the difference.
Title: Re: Cam support plates "B" vs A motors..
Post by: smoserx1 on February 03, 2020, 03:23:43 PM
Yes I had first hand knowledge about this issue because I have an early 1999 motor that lacks the oil boss and when I went to conversion cams with the 2007 cam plate I had to block the hole.  The kit that Harley supplied was this:

https://www.ebay.com.au/itm/KIT-TAPON-PLACA-DISTRIBUCION-HARLEY-DAVIDSON-94667-00-Cam-Plate-Support-Kit-/322253759962

It uses a self tapping pan head screw and I have heard is hard to find these days.  Andrews recommends using a 1/4 X 20 X 1/2 inch headless set screw instead after tapping threads in the hole.  Either way should work fine but every now and then someone updates the cam plate on an early 99 and does not know about this.  Oil will flow freely out of the unblocked hole flooding the cam cavity and reducing pressure and flow anywhere downstream of this port, but the issue is rarely encountered anymore since it only applies to the early 99 engines.  Definitely not an issue for anyone with a 2000 or later motor, A or B.
Title: Re: Cam support plates "B" vs A motors..
Post by: motorhogman on February 03, 2020, 03:54:06 PM
Smoserx1 and Scotty.. Good information.  hopefully somebody will benefit from this thread in the future. 

Wondering why we need an o ring on that blocked port.. To stop oil from spurting out the sides of it ? 

Title: Re: Cam support plates "B" vs A motors..
Post by: Scotty on February 03, 2020, 04:00:29 PM
Quote from: motorhogman on February 03, 2020, 03:54:06 PM
Smoserx1 and Scotty.. Good information.  hopefully somebody will benefit from this thread in the future. 

Wondering why we need an o ring on that blocked port.. To stop oil from spurting out the sides of it ?

Yes the oring stops the oil leaking around it.
Also don't use a 99 cam plate in a softail motor or the balancers won't get any oil  :oil:
I still have a few of the HD kits here with the bolt to plug the port as I only ever used one.