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MrDan
01-05-2011, 11:05 AM
I've been collecting parts for building a log splitter, referenced in a previous thread. I've been able to scrounge a basically new cylinder that I'm going to use for the splitter, but since it's off of a very large piece of equipment, the cylinder does about 88 tons of force. Rather than be rational and use a smaller cylinder, I want to use this overly large cylinder and also use this project as a hydraulic press/forge. The issue with using an oversized cylinder is it takes a bit more oomphf to drive it. I scrounged up an 18hp gas engine we had in a broken welder but according the the math I need something closer to 25-30hp to drive this thing. I checked around with our guys and it turns out we have a Perkins 3 cylinder diesel engine with about 40 hours on it that "spun a bearing." The engine is complete and seems fine other than the bearing issue. It was replaced for the customer under warranty with a complete new engine so we have a basically new engine that I have zero cost in.

Here is the data plate on the engine. http://gallery.me.com/mrdan27611#100071/IMG_0013

My first thought was to tear the engine down and see what I've got. We did most of that (the crank is still in the engine, everything else is out) and the bearing hasn't "spun", it just got cocked and scored the rod journal on the #2 piston. I thought we could order oversize bearings to get this thing back together but Perkins wants over $500 at our cost for the bearings. Then I thought maybe just buy the crank but they want about $1100 for the crank, which still needs regular bearings for a few more hundred dollars. I can take pictures of the damage to the journal if it matters, but my choices seem to be:

1. Forget it. Use the 18hp engine.
2. Try to weld the journal up in the block to hold it. Then try to get it back in true somehow as best as possible. Then pull the crank, turn it down on the lathe and grind/hone/etc.
3. Spend $500 and get oversize bearings. Pull the crank and turn it down, grind/hone/etc. then put everything back with oversized bearings.
4. One of you guys tell me where I can get oversize bearings and not get raped on the price.
5. One of you guys tell me the obvious thing I'm missing and why I should be doing this another way.
6. Wait for another engine to appear, we do get them on occasion but they tend to be 150hp and have other issues.

Option 1 Pros are, already done, and it's free. Cylinder may be slow, may not. Don't know till I try. Cons, if it's slow, then I have to undo all the work to get it together. I don't like doing things twice.
Option 2. Welding is not recommended on this by a few people and I don't know if I'll ever get the crank back in true. If I really screw it up, I can always buy a crank anyway. TIG isn't my forte and I'm told it's the way to do a crank if I'm dumb enough to try.
Option 3. I still do all the machining work, and I'm not sure I can hone the journals appropriately anyway. Trying on a free crank is just practice and a good learning experience. Trying when I have $500 invested is now a serious need to be right.
Option 4. I'm hoping you guys can pull me out with Bearings-are-us.com for some generic bearing.
Option 5. As the newb, I'm used to being shown the obvious everyone else knows.
Option 6. Not bad. The next engine may be 40 hp, or have a pump with it. I'd just really like to get this project started and finished this winter. I don't do much in the shop after March 15th so I'd have to wait till next winter, which means I won't have any wood next winter without buying it. Not the end of the world but not preferrable.

As always, thanks for your help and information. I can of course provide additional details that I probably did miss.

Carld
01-05-2011, 11:16 AM
I will suggest you contact some after market bearing suppliers. Federal Mogul and others for instance. If the crank is not scored you may be able to polish it out and use standard bearings. You can use Alum to possibly remove any build up from the crank. Even if you have to have it turned down .010" under you should be able to get bearings at a reasonable price from outside sources.

The 18 hp engine will work, it just may not get the full pressure and you may not need it anyway. There is an alternative, you can go to a double stage pump and avoid the problem. The double stage uses the low pressure high volume until the high pressure is needed and switches over to a low flow high pressure system.

You don't want to try welding unless your very good at heat control, fracture diagnosis and have a crank grinding machine.

Willy
01-05-2011, 11:43 AM
Exactly what Carl said.

What are the flow and pressure requirements?
Do you have a pump already?
Will you be using all 88 tons of the cylinder's capacity?

Stepside
01-05-2011, 02:46 PM
Even a lawn mower engine would do the job. It is an issue of how fast you want to move the piston in the cylinder. A small pump with a small motor is capable of creating the same PSI as a large pump with a large motor. With one you use a stopwatch to time it and the other you use a calendar.

My wood splitter uses a 20 ton hydraulic jack. If I have a bunch to split I rent the largest one I can find. The jack serves double or triple duty as my hydroformer press as well as a "jack of all tasks".

Black_Moons
01-05-2011, 02:49 PM
Id recommend the 18HP and spend the money you saved on a nice two stage pump...
PS: with big cylinder, you'll need a big resavor that could be.. excessively big.

Oldbrock
01-05-2011, 03:05 PM
Have you measured the throw? Could be the size is still good, a little galling can be polished out and standard shells used. If the journal is out of round and undersize, pull the crank and just have that one journal ground and get one underize set of shells. Make a note on the engine plate that #2 throw is 10 thou under. Should be good to go. You don't say what size pump you have. The 18hp should be good with the right pump. Sizing it is not my forte, I'm a machinist not hydraulic wise. The Perkins brings up memories of Home Improvement where a hemi was put on a lawnmower. Whatever you do, good luck and have fun, Peter

MrDan
01-05-2011, 10:20 PM
I knew I'd leave out half the details. Sorry about that. I got home and took a picture, as best I could, of the rod journal.
http://gallery.me.com/mrdan27611#100076/IMG_0019

I can't catch a nail on the scoring that is visible. I'm basing the need for repairs on one of our master techs who tore this engine down the first time and diagnosed the problems. He basically said, "Spun bearing, needs a new crank and bearings." Now one thing our guys are guilty of being that we are a dealership is, if it's broken, cracked, worn, bent, etc, pull it off and slap a new one on and bill somebody. We really don't do a lot of fix it it'll be ok repairs. Anyway, I'm not really sure at this point what the root cause was of the failure and if just polishing out the journal is a realistic option. I'm assuming at this point that the journal had to be some kind of undersized to allow the bearing to spin in the first place. I guess the next step would be to go ahead and pull the crank since welding is frowned upon by you guys as well. Then I can do some measuring and see what we have, and hopefully post better pictures.

As for HP vs. pressure and what not. I completely left that part out, sorry. You are all correct, HP doesn't equal pressure so much as it equals flow. I'm specing about 3000 psi and I'd like this cylinder to move at about 3" per second unloaded, which works out formula wise to about 30HP and 25GPM if I recall. I do plan on having a two stage pump, but am currently trying to scrounge up a pump from work so may have to just take what I can get. We had a pressure compensating pump we just got rid off which would have been great so my hopes are up for something else that may come along in the warranty/scrap bin. We use some pretty amazing pumps in our work so scoring one from work would probably beat most anything I could buy.

As for the reservoir being large, I already did the math on that and what I have now will work as long as I don't run into heating problems with too little reserve capacity, which with the duty cycle shouldn't be a problem. I'm not using any hydraulic coolers. I'm using a box section cross beam for an axle and it'll hold the oil I need and not really add to any dimensions. Plus it has lots of surface area so that should help with cooling as well.

As for the comment about Tool Time and the hemi lawnmower, I'd say you're spot on except if that were the case I'd be bolting a 150hp John Deere 4045 engine up and trying to make it work, or maybe a 6068 with 200+. (Insert Tim Taylor grunting here) It's easier for me to get those than these little dinky Perkins engines, and easier to get parts/pumps/etc too. :)

Part of the appeal of using this Perkins engine is that this is a shop project for me to learn on. Originally the thought was that I have a zero cost engine that was literally going in the scrap bin so if I can fix it, great, I'm a hero. If I can't, it goes in the scrap bin where it was headed anyway. The kink in that plan is $500 for oversize bearings. If I spend $500 and then throw it away, that's bad. The name of an aftermarket bearing company was exactly what I needed. Thank you, CarlD, we'll start running that down tomorrow.

As for using the whole 88 tons, who knows. I have some plans to do some forging and being able put plenty of force into hot metal in a hurry would be pretty handy. I know 20 tons would probably do what I need but I've always gone oversize on tools and never been sorry, especially when I'm scrounging the parts gratis.

If anybody has any other companies that might have bearings I'd sure appreciate the leads.

Thanks, as always.

Don Young
01-05-2011, 10:50 PM
Looking at that picture, I would judge that you need to have that journal reground by someone with a crankshaft grinder. It is not expensive, you just need to convince him that you only want that one journal ground as it is common to grind all rod journals to the same size. Don't waste time and money trying to smooth it any other way.

Unless there is something very special about that engine the shop that grinds your crankshaft should be able to get a correct UNDERSIZE bearing for less than $100. The correct size cannot be determined until the crankshaft is ground. I find it hard to believe that $500 is the correct price for one bearing from Perkins, maybe for a complete set.

As others have said, horsepower is a measure of how fast work can be done, not whether it can be done. You can operate a full size car with a 1HP engine, it just won't go very fast. I think 18HP would be enough power for a reasonable speed in your application.

Oldbrock
01-05-2011, 11:18 PM
Oh, good grief, that throw looks totally fried. Might clean up at 10 under but I doubt it. The rod will have to be resized too as it is likely stretched out of round. 20 thou under is no biggie and undersized shells should be available from the jobbers.

Robg
01-05-2011, 11:22 PM
I ran an automotive machine shop for many years (teaching Mechanics now) but I'm an amateur in the home machine shop. Even though the picture is so-so, I can tell you that the crank & rods must come out and go to a auto machine shop. First, have the crank magnafluxed for cracks before you do anything. If cracked, you have a boat anchor. Must be ground undersize with a crank grinder if ok. Next, resize the con rod big ends and align hone/bore the main bearing bores - this is a MUST-do, don't cheap out or you will regret it later. Trust me - I speak from long experience here. A new oil pump is a given. Check the pump pickup for flaws - cracks, air leaks, etc. Clean everything.
Shop around for price on the bearings. I can't advise if the engine is suitable for your requirements. Hope this helps.

914Wilhelm
01-05-2011, 11:31 PM
Building a C-shaped open press at 88 tons (the basic shape of a log splitter) is going to take a helluva a lot of steel not to deform. All that steel plus a large diesel engine is going to make an unwieldy hard-to-manhandle log splitter you will rapidly decide it is a pain in the butt to use. I'd use the 18 hp plus a 25 ton cylinder to make something I would be able to use. Save the 88 ton cylinder for a H-frame press that you won't destroy.

bborr01
01-06-2011, 12:54 AM
Mr Dan,

If you want an 88 ton log splitter that will do other things, that is fine.

Just understand what 88 tons of force will do. I have had things happen inside of a press at 75 or 100 tons that cracked the 1" lexan shielding around the press. The sound kind of reminds me of a 30.06 going off only maybe a little louder.

Be careful with that kind of power.

Brian

MrDan
01-06-2011, 06:20 AM
Building a C-shaped open press at 88 tons (the basic shape of a log splitter) is going to take a helluva a lot of steel not to deform. All that steel plus a large diesel engine is going to make an unwieldy hard-to-manhandle log splitter you will rapidly decide it is a pain in the butt to use. I'd use the 18 hp plus a 25 ton cylinder to make something I would be able to use. Save the 88 ton cylinder for a H-frame press that you won't destroy.

I agree with everyone here, 88 tons is just stupid over the top. Had I not come across this cylinder I wouldn't consider it but eh, I've got basically nothing in it. Why not overbuild it? The main beam I beam will give out (start to flex) long before the cylinder does, even though it's quite stout so we won't be seeing 88 tons in use, and for wood splitting we'll only see whatever it takes to split he wood itself. For forging it'll be overkill as well, I'm sure. Duly noted though, safety first. I've got a small H frame press in the works as well that will do more of the real pressing in the shop. This thing is sort of like building a hot rod. Fun, good learning experience, totally over the top, but it's useful only in a straight line or pretty Sundays.

As for being to unwieldy to use, of course you are correct. No picking up the tongue to hook it to the truck, but my intention for the splitter on day one was to make it electric with a large motor and have it sit permanently in one spot. It'll most likely never leave the farm and if it does, you are talking to the guy who keeps a crane parked on site. I'm sorta used to oversize and unwieldy.

Thanks for the advice on getting the crank ground. 500 is for a complete set of oversize bearings, but that's the only way they will sell them. They will not sell just one. Of course, a complete set of standard bearings is $140 from Perkins. I'm starting to reach the point where the outside money spent is going to outweigh the extra few horsepower of this engine. I've got $0 in the 18hp so just on cost I may have to go back to it. It would be fun to fix this thing in my shop if I could, as a learning experience. Outside money takes the joy out of it, though.

And because you can get in trouble on youtube, someone point out the flaws as to what is going on here. http://www.youtube.com/watch?v=V82WnutmFAk&feature=mfu_in_order&list=UL

Besides him not covering up his ways and then grinding, I mean. I get that mine needs oversize bearings and crankshaft grinding, I'm just curious here. He's "polishing" he says, only taking a few thou off, but with no tolerances. I'm working on the assumption that on this crank we can't be off a 10 thou. I mean, it's a crank shaft. Thoughts?

MrDan
01-06-2011, 06:44 AM
I ran an automotive machine shop for many years (teaching Mechanics now) but I'm an amateur in the home machine shop. Even though the picture is so-so, I can tell you that the crank & rods must come out and go to a auto machine shop. First, have the crank magnafluxed for cracks before you do anything. If cracked, you have a boat anchor. Must be ground undersize with a crank grinder if ok. Next, resize the con rod big ends and align hone/bore the main bearing bores - this is a MUST-do, don't cheap out or you will regret it later. Trust me - I speak from long experience here. A new oil pump is a given. Check the pump pickup for flaws - cracks, air leaks, etc. Clean everything.
Shop around for price on the bearings. I can't advise if the engine is suitable for your requirements. Hope this helps.

This is the advice that is scaring me off this project. Pretty much everything you're suggesting is outside work or new parts. I'm certain that this engine would be tip top if I did all this, but it is for a log splitter for home use. This sounds like what we would do if we were to put it back into a customers hands. I really was hoping for a not simple but doable home project but all this is sounding like too much for my abilities. This thing may have to go back in the scrap bin for .10 a pound instead. Shame too, because otherwise it's basically new.

Ed P
01-06-2011, 09:13 AM
If you want to speed up the cylinder rod speed, before it gets loaded up, just use a regenerative circuit.

Ed P

tdmidget
01-06-2011, 09:29 AM
The data plate foto is to small to read. What is the engine family?

MrDan
01-06-2011, 11:39 AM
The data plate foto is to small to read. What is the engine family?
Sorry, it was really huge when I uploaded it. Don't know what happened.

The family number is 6H3XL1.13SLV

tdmidget
01-06-2011, 11:33 PM
Check 'em out:
http://www.agkits.com/Perkins-Connecting-Rod-Bearings.aspx

Willy
01-07-2011, 12:59 AM
tdmidget, the OP's engine is a 1.13L engine, much smaller, and more importantly much less common than those listed in your link.
Those engines have been used in every conceivable application for many years, hence the low prices.

Without having made phone calls to Perkins engine parts suppliers, (which won't be a waste of time), I have yet to see a listing for bearings for the engine in question. I have a Clevite engine bearing catalog for example that I thought was very comprehensive, and although it lists a lot of Perkins engines, there is no mention of the 1.13l engine.

Perhaps a reason for the high bearing price.

GKman
01-07-2011, 07:05 AM
Put it back together as a twin and see what happens.

tdmidget
01-07-2011, 07:09 AM
Willy, I said check 'em out, I didn't say here it is. Odds are that a Clevite dealer who sells parts for a Buda will have no trouble with a Perkins.

JCHannum
01-07-2011, 08:48 AM
I am a minimalist and cheap. The photos of the crank throw and the description are kind of at odds to each other. By the description, the throw sounds salvageable, with what appears to be scoring in the photos being detritus from the bearing shell welded to the crank.

If this is the case, I would clean up the crank in place by polishing it out with emery cloth shoe shine style. Start around 240 grit and work up to crocus cloth. See what it looks like and take a measurement. You might still be able to use a standard bearing. It takes quite a bit of work to remove a significant amount of material from the crank, but the bearing material will come off quite easily.

In use, the engine will not be heavily loaded, the duty cycle of a log splitter is probably 25% or less, idling most of the time, and unless it is a business, use is sporadic. Even with light scoring, that engine could run a long time, the only risk is some time, abrasive cloth and a bearing.

tdmidget
01-08-2011, 11:40 AM
Well Dan, were they able to help you?