Hello All:

             Whenever I tighten the prop nut, my engine, it becomes very tight and difficult to turn.  The engine is a HP .40 Silver Star.   I have 6 other HP .40 engines that I have,  do not do this.  What is wrong? I can not see any difference in the way that these engines are assembled.

              Suggestions/comments?

                                                                                                    Tia,

                                                                                                     Frank McCune

                                                 

Frank
you have a bearing that is not in properly, or not seated, OR  you have a collet on the front that is not  pushed all the way back to touch the inside race of the  front  bearing, most likely 1 of the 2

Randy

             Hello All:

             Whenever I tighten the prop nut, my engine, it becomes very tight and difficult to turn.  The engine is a HP .40 Silver Star.   I have 6 other HP .40 engines that I have,  do not do this.  What is wrong? I can not see any difference in the way that these engines are assembled.

              Suggestions/comments?

                                                                                                    Tia,

                                                                                                     Frank McCune

                                                 

Is this engine  recently, just  put back  together ?

Randy

          Hello All:

          Thanks to all of those who replied!

           After a night’s rest, I made the following observations:

The p&c still have a great seal.

I do not know if this engine was recently assembled as I received it with an unknown history

I pulled the prop driver off three other HP 40 engines and I noticed that the front bearing is recessed about 030” in the case. The problem engine has the front bearing flush with the case. Perhaps it is time to pull the front bearing to determine why the bearing is not fully seating.

           I “found” a steel shim that will fit over the crankshaft and inside of the case  It is about 030” thick. Does this belong in the bearing assembly If so, where

           How does one remove the crankshaft and bearings from the front housing of this engine

                                                                                              Tia,

                                                                                              Frank McCune

Don't remove any bearings.

Put a prop on it, heat up the case to about "spit" hot, and while it is still hot tap on the end of the crank shaft with a mallet to seat the front bearing.

Tighten up the prop again, repeat as required.

You can also tap on the back of the crankshaft to seat the rear bearing. Works better if the rod has been removed.
 I have various  little delrin tools that fit in the case and have a hole in them to clear the crank pin to make this easier.
I made mine after I saw Henry Nelson install the bearings in one of my N15RV this way.

If this all fails then you might be missing the spacer that was previously mentioned.

I know ideally you would press on the outer races to install both front and rear bearings, but without special tools you do what you can.
Pressing from the inner races this way can (and probably does) lead to damage to balls and races, but in my experience this is not an issue.

(flame suit on )

Pat MacKenzie

Some of the PAW diesels have this problem and it mentions it in the insructions.

Do those engines have a spacer behind the front bearing like a SuperTigre?

We referred to that part as the forget-me-not.

     Hi Brian:

     Thanks for the info.  Thus far, I have not seen any shims for the HP engines.  I will continue to look for them.

     The slit collet intrigues me as it appeared to be slightly flared on the larger end.  This may be an indication that the thrust washer may have been forced too far to the rear.  If this were the case, I doubt that a shim would have served a useful purpose.

      Be well,

       Frank

     Hi Brian:

     Thanks for the info.  Thus far, I have not seen any shims for the HP engines.  I will continue to look for them.

     The slit collet intrigues me as it appeared to be slightly flared on the larger end.  This may be an indication that the thrust washer may have been forced too far to the rear.  If this were the case, I doubt that a shim would have served a useful purpose.

  If so then the shim will provide the necessary clearance. It's pushes the entire collet forward, which is 1:1 with the clearance to the case.

     Brett

p.s. by the way, reading back through this thread, I would caution everyone about doing anything to load the inner race of the bearing to either pull it out or push it in. If the press fit is on the outer race, you want to press on the outer race only. That keeps the balls and ball race out of the load path. I see several suggestions about pushing the bearing from the inner race above. If you do that because there's no other way (like to get it out from pushing from behind), then, assume it is damaged and replace it. A bearing is cheap compared to losing an entire weekend at a contest after it fails, or collateral damage from a failure trying to work itself out the exhaust.