DAKOTANOVASS

My Feedback: (17)

I am currently trying to rebuild a FS-48 and can not get the wrist pin out. So was thinking of cutting the rod to get it apart. I noticed the new cranks are steel versus the stock aluminum in the motor. Is their anything wrong with the new steel cranks.

Terrell

cahusker

My Feedback: (50)

Have you removed the sleeve? You have to take it out first then you can get the rod off the crank pin, it might take a bit of a tug. You can't get if off otherwise.

proptop

My Feedback: (8)

Not sure exactly what you mean, but I think you're talking about getting the bottom end of the connecting rod off the crank pin?

All of the O.S connecting rods that I have ever come across are Aluminum.

I think what you need to do is slide the con rod back far enough to get it off the crank pin.
There might be varnish/gum on the wrist pin which is preventing that?

Edit: I think we have a terminology problem here?

rainedave

My Feedback: (1)

I'm not sure about the .48, but the FS .40 Surpass has a hole in the back of the crankcase that is used to extract the wrist pin.

If your engine has a hole in the back of the case you will not be able to get the connecting rod off of the crankpin with the piston still attached.

You must pull out the wrist pin through the hole.

Do this by using a drill bit that will fit snug into the hole in the wrist pin and pull it out. You might have to heat the engine in a 300° oven or soak it in a solvent first if it's stuck.

Please do not saw through the connecting rod.

David

proptop

My Feedback: (8)

rainedave has it...
You might need some penetrating oil as well PB Blaster works well.

Campgems

I'm assuming that it's a four stroke. Pull the head. Notice the hole in the back of the crank case, Pull the sleeve up just enought to get full access through this hole. Crank the engine over until the wrist pin is lined up with the hole. You should see a white teflon button with a small hole in it. Use a #2 sheet metal screw slightly turned into the hole and pull out this teflon button. If you are lucky, you can tap the wrist pin out, but I've never been that lucky. Try a $4 sheet metal screw into the hole of the wrist pin and once it bites, you can usually pull the pin out by continuing to tighen the screw whill pulling it out at the same time. People have also used small easy outs to lock onto a stubborn wrist pin.

The reason not to fully remove the sleve is that if you do, you stand a very good chance of breaking the ring. If the engine isn't really baddly worn, you don't want to mess with the ring.

I'm sure you don't mean the crank is aluminum, the push rod maybe. There is nothing wrong with aluminum rods,

Don

DAKOTANOVASS

My Feedback: (17)

I have the sleeve out, it has soaked in PB Blaster for days, I have tried heating the piston and rod. The hole in the pin is between any drill bit I have, also have tried using screws to extract the pin. Nothing works on this blasted pin. As far as the connecting rod, I held a magnet to it and does not stick so it must be aluminum. On Tower Hobbies they list theirs as being steel with brass bushings. My concern is with reciprocating weight. I would prefer to keep the aluminum one, but if I cant get the pin out, I will have to cut it apart.

gkamysz

My Feedback: (19)

Tower Hobbies often has incorrect item descriptions. The replacement rods are aluminum. Try a screw extractor to get the wrist pin out. If you try that slide the piston back into the sleeve so you don't damage the piston.

proptop

My Feedback: (8)

Yep...use an "easy out" and tap it in gently with a light hammer then grab it w/ vice grips and pull/twist after heating it up again.

w8ye

My Feedback: (16)

small deck screws seem to work pretty well. They are hardened and the threads will not strip off

chistech

I rebuilt my 48 about 2 years ago. Mine wrist pin also was stuck. I did everything that you did and it too, like yours, didn't want to come out. I have a industrial heat gun so I put it blowing on the back of the open motor and left it. After about 15-20 minutes and it being extremely hot, I sprayed the wrist pin end with WD-40. It smoked a lot and I went to work with the easy out. It did come out. It is a pain but be persistent. If you need a ring, Frank Bowman has it and they are great. If I was you I would replace the ring. I also changed the carb out with a Magnum 52 carb because I run this motor inverted and couldn't get it to idle consistently with the original air bleed carb. This motor starts and runs great and turns a 12x4 prop at 10,100. It is just a great all around motor and now has many hours on it. Good luck with yours.

w8ye

My Feedback: (16)

[email protected]
Frank C. Bowman
1211 N Allen Ave.
Farmington, NM 87401
505 327 0696

w8ye

My Feedback: (16)

Here's the Magnum 52 carb. Your original intake manifold will work with the new carb
The carb will fit the engine like it was made for it.
http://www.hobbypeople.net/gallery/280010.asp

chistech

Sorry, forgot to tell you another thing I did to help get it out. I took a piece of hard wire and put a 90 degree bend in it. I then ground the end flat and also the inside of the 90 making it a hook. I ground it enough so it would fit into the wrist pin hole. Harden the wire with heat to treat it. If you push it into the wrist pin through the hole in the back of the crankcase while holding the piston against the back of the cylinder it will push out the other teflon end. If you made it right you can use it to "hook" over the back end of the wrist pin to pull it out. I used the largest wire drill I had that would fit in the wrist pin hole along with my "puller" wire. This helps keep the puller hooked and doesn't allow it to slip off the end. I know it is a small hole and there is not much room but with a little thought you will be able to make it work.

DAKOTANOVASS

My Feedback: (17)

I finally did get it out tonight with an easy out. Now the darn pin is stuck on the easy out. I also have a new ring coming from Frank already. I would like to put on the 52 carb, but money issue comes into play.

Terrell

w8ye

My Feedback: (16)

I had a OS 52 carb on mine.

The pin is the same in the OS 52 if you need one and the pads. The bore is the same.

And the 48 pin is still available
http://www3.towerhobbies.com/cgi-bin...?&I=LXCT12&P=7

Campgems

Get a couple 1/4" slices of hardwood. A ruller, Yard stick or make your own. Clampn one on each side of th pin, with the grain running 90 degrees to the length of the pin. Grab them with visegrips set quite tight and then take the easy out out. Just rememter to screw it in.

Don

DarZeelon

Quote:

ORIGINAL: rainedave

If your engine has a hole in the back of the case, you will not be able to get the connecting-rod off of the crank-pin with the piston still attached.

David,


"[link=http://en.wikipedia.org/wiki/It_Ain%27t_Necessarily_So]It ain't necessarily so[/link]" (©-George and Ira Gershwin 1935 - Porgy and Bess. Also sung by several others in later years)...


Webra Speed .40 engines also have this aluminium screw plugged hole, in the back of the crankcase, for access to the wrist-pin (the pin retainer clip must first be removed)...

...Yet, if one removes the cylinder sleeve and slides the rod's top-end as far back as it will go along the wrist-pin, in the underside of the piston; the rod's bottom-end can EASILY be unhooked from the crank-pin, like in most other engines with a one-piece crankcase.


Off-subject, maybe; but important nevertheless.

EDIT: Grammar.

gkamysz

My Feedback: (19)

Dar, I like how this is questionable, and yet if a bearing has a seal it must be hermetic.

rainedave

My Feedback: (1)

I enjoy Dar's critical epistemology of what he might call "model engine dogma."

David

DarZeelon

Greg,


I have always preferred black/white to varying shades of gray, so to speak.

Also, I prefer accurate terms, to 'borrowed' terms.


So, a bearing seal should seal and a bearing shield should shield. And if a seal cannot seal under its stated operating conditions, but does shield the bearing from ingestion of dust and grit, then it is a shield, regardless of what its manufacturer calls it...

And if some newbie says his single-cylinder glow engine 'spools up', or 'flamed out' (both terms 'borrowed' from turbine engines), I will correct him, because these do not correctly describe what happens in his engine...

...If this person is offended because I 'blew his turbine bubble', then he should simply face the fact that his glow engine is actually not the turbine he had dreamt of owning...


And David, yes, I have burst some 'model engine dogmas' in this forum, such as the 'popular thought' that accumulated fuel in the crankcase during idling (loading-up), is used by the engine to make up for the non-existence of an acceleration pump in its carburettor.

I do like blowing away mistaken thoughts and 'myths'... Especially I am fond of arguing with those that 'defend' a widespread 'belief' that nobody gave a thought to, before simply accepting it, as G-d's own words...
Some people do not let actual facts confuse them; and thus require a lot of 'verbal arm-twisting', before they are ready to accept the new facts as such (and their previous mis-belief as such...).

gkamysz

My Feedback: (19)

But you are insusceptible to verbal arm twisting. I tried to get you to just say, wow I didn't know that, or thank you for pointing out my ignorance, but nothing. Not even an explanation of your stance other than defining the term used. I think we already new what the word seal means. Everyone says that a woman is either pregnant or not. She can't be a little pregnant. The fact is, even though she is pregnant, there may not be a bright bouncing baby 40 weeks later, by choice or not by choice, and there are times when she is blessed with more than one baby. Clearly being pregnant guarantees little more than bringing your wife ice cream and pickles at 2 AM.

We live in an analog world in the digital age. Not everything is a 0 or 1.

If an engineer denies the "what if?" situations he will be sorely surprised when it occurs.

Dar, I still enjoy your posts, but you can't deny your peers to review your responses.

DarZeelon

Greg,


I must say that I also enjoy reading your posts.
You are knowledgeable and also know what you are talking about (note the nuances...).

I even enjoy arguing with you over the forum, as it is both enlightening and challenging...


I have my faults and I am quite opinionated, but I believe I do, or at least I try listening to reason and I have been proven wrong on occasion.


If I have I always stand corrected. I will never argue to make my incorrect assumption, or incorrect statement, correct.


I also use that pregnancy example that you had pointed out... However, Greg, in our digital world there is nothing but binary ones and zeros...Anything in between is analog. (Gotcha! )

gkamysz

My Feedback: (19)

Dar, then we can agree.

My CD player sounds better with a tube preamp output stage and a tube input stage amplifier. I don't have a pure tube amp, but I don't have time anymore for audiophile hobbies. I did dump all my CRT's for LCD's, though I did prefer a good CRT for CAD work.

rainedave

My Feedback: (1)

Greg, another tube head! Cool.

I had an Ah! Tjoeb tube CD player but sold it since I like vinyl better.

David