Cat 225 LC rear main seal replacement project

[Nige]

Nige, how does the melting of candle wax on threaded fasteners actually work??

I think it's capillary action, similar to what happens with soft (lead) solder on copper pipes. You get the copper hot then touch the stick of solder to it and as if by magic the solder gets drawn into the joint. That would make sense to me but I am not 100% sure that's how it works. The candle wax trick definitely works on threaded fasteners, there's no reason why the wax wouldn't wick into the gap between the plate and the flywheel in theis case.

 

[Dapperdan16]

Raining in NJ... say it ain't so....lol


Hey zbo2, it seems like there is no end in sight with all this rain/thunderstorms, kinda like the adapter plate I'm trying to remove from the Cat 225, haha
Danny

 

[Dapperdan16]

I think it's capillary action, similar to what happens with soft (lead) solder on copper pipes. You get the copper hot then touch the stick of solder to it and as if by magic the solder gets drawn into the joint. That would make sense to me but I am not 100% sure that's how it works. The candle wax trick definitely works on threaded fasteners, there's no reason why the wax wouldn't wick into the gap between the plate and the flywheel in theis case.

Makes sense to me Nige, just got home from work, gonna go put some heat on the adapter plate. I'll report back and let everyone know how it went, "Fingers Crossed"
Danny

 

[Dapperdan16]

Well, the heat did not work. I tried just heating the flywheel outer edge best I could with no results, then I tried heating the face of the adapter plate with no luck, tapping on the face of the plate and the puller with a hammer. At this point, I feel like something is still fastened or I am not using the puller correctly???????? but I know that's not the case. Thats how tight it's on there. I guess the last thing I can try is the wax trick Nige mentioned, it was getting to late to try tonight. I do have one question, how hot am I supposed to get it, just warmed up pretty good, red, cherry red??
Danny

 

[mitch504]

A good glowing orange.

 

[Dapperdan16]

A good glowing orange.

Thanks Mitch, I didn't have it close to that hot, I was afraid of warping it or damaging it in some sort of way. I'll be back at it tomorrow after work. I still can't believe how tight it's on there, the puller is so tight that the 5/8 puller bolts started to bend. Have you ever personally removed one of these adapter plates before? also, have you ever replaced a rear main seal in a 225 with the 3304 engine? thanks again
Danny

 

[mitch504]

I did one in a 215 w/ a 3304, I just used my healthy Snap-On puller and a BFH, one thing that might help you is to change those single flat washers for thick hardened ones. My puller has thick, square pieces of tool steel that actually hook over the outer edges.

 

[Dapperdan16]

I did one in a 215 w/ a 3304, I just used my healthy Snap-On puller and a BFH, one thing that might help you is to change those single flat washers for thick hardened ones. My puller has thick, square pieces of tool steel that actually hook over the outer edges.

Very good point, the one in the manual actually hooks over the edge. I haven't lost hope, so I guess thats good. I love a challenge and really am enjoing working on this excavator with my 75 yr old father "it's my first excavator" thanks again
Danny

 

[lantraxco]

Very good point, the one in the manual actually hooks over the edge.

Hooks over what edges?

 

[mitch504]

The puller I was talking about looks vaguely like his, and has plates that extend over the sides of the puller to keep the puller from spreading.

 

[Cmark]

Don't go nuts on the puller. The last thing you want to do is strip the threads out of the plate.

 

[mitch504]

Good thought, a little pessimistic, but good.

 

[Nige]

Personally I think heat could be the key - lots of it .......

 

[Cmark]

Good thought, a little pessimistic, but good.

When you've been doing it for a while you develop a knack for spotting disasters on the horizon.

 

[etd66ss]

I have been following this thread. I have to say, from personal experience turning wrenches on stuff for ~25 years, I don't like the cherry red/orange heat idea in a situation like this. The puller you have on there right now is what I would use, and I agree with mitch504 about the washers. Regular washers, even grade 8, are not going to cut it. The washers will just get extruded into the puller H-Beam. All steel acts like a spring, you need to add more inertia to the washers or spacers you use to decrease deflection, you do this by making them thicker. You also have to keep the "tuning fork" portion of the H-Beam puller from splaying apart. If you have thin springy washers in there, when you pound on the puller screw you're not transmitting the shock loading to the adaptor plate in a manner that will break it loose. Much thicker spacers or proper keeper plates, and making sure the bolts threaded into the adapter plate are FULLY engaged in all the threads available is where you need to start. Without having a parts book for this unit to see a cross section, I am making some assumptions on the anatomy of the assembly, I'm going by what I see in your pictures, I could have it way wrong.

I made a mock up of what you're trying to do and rendered out some pictures:





I see that you have nuts and washers on both sides of your H-Beam puller, that seems wrong to me if the H-Beam has a threaded hole in it. If that hole has wiped out threads, or if it is just a thru hole, it makes the puller a bit more cumbersome than it should be.

I personally would not overheat anything here... This is a part that sees vibration and flexure. When you heat steel hot enough, you change the crystalline structure of the steel and you can make it brittle. The adapter plate could become brittle and grenade apart on you at some point in the future.

IMO, moderate heat (map gas torch from Home Depot etc) while keeping a ****ton of torque on that center puller bolt while hammering on the end of said bolt with a steel 6lb sledge should do the job. Again, if your H-Beam is splaying, and your washers/spacer are springy, you're not transmitting the shock loading properly, and it makes it hard to break the pilot press fit free.

Full resolution of the above pics can be seen here: http://imgur.com/a/WrmhZ

 

[mitch504]

That's exactly the type of washers or plates I was talking about, etd.

Fantastic drawings, BTW.

 

[lantraxco]

Anybody got a picture of the actual CAT tooling, just out of curiosity?

 

[Nige]

Anybody got a picture of the actual CAT tooling, just out of curiosity?

Pretty much identical to what was posted on the previous page ......

 

[kshansen]

I made a mock up of what you're trying to do and rendered out some pictures:

Quick question. What program did you use to make those drawings, very nice!

 

[etd66ss]

Quick question. What program did you use to make those drawings, very nice!

I'm a mechanical design engineer by day, the software is called Autodesk Inventor, it's a 3D CAD design software package. http://www.autodesk.com/products/inventor/overview