rod bearing help

[rentthis]

One of my non Kubota machines has a small Perkins diesel engine. I'm rebuilding the engine. The problem I have encountered is getting rod bearings. They are available in standard for $140.00. That's to high but doable. 10 over bearings are $925.00. I have tried to find out what the difference in price is but no luck. My question is, does anyone know of anyone that manufactures bearings that might be able to copy or match what I have in 10 over? Are these bearings proprietary to the engine or is there a way to match them some other way? I can have the crank welded back to standard and use standard bearings but it costs $250.00 per journal to do that. That's a lot to pay to lower the bearing price. Not to mention not a good idea considering the heat necessary in welding. Thanks in advance for any assistance.

Mike

 

[85Hokie]

"That's to high but doable. 10 over bearings are $925.00."

does this include the new crank?

That does sound a bit strange - I hope there is a misprint somewhere?

 

[007kubotaguy]

What engine are you working on.

Lance

 

[North Idaho Wolfman]

Yea the engine spec / model would help us out!

 

[Tooljunkie]

So i bet you can import from england much cheaper than quoted price. I did a quick search and there are aftermarket perkins parts suppliers in the UK.

Im just thinking $925 is the "we got you over a barrel"price.

 

[rentthis]

I can't come up with a reason for the price. I have ordered them after market and the bearings I get are way too big. I clicked on Hudson's Ebay link and found another after market source that has them in a different brand. I spent $45.00 to order his set hoping for a fit. The model number is Perkins 403c-11 and the build number is HH35118UC. I did get a price from England. They have them for 350.00 pounds sterling. I'm told that translates to just shy of $500.00 not to mention figuring out getting them here and wondering if they will be the right size.

Thanks for your replies. This has been a pita but I can't say it hasn't been interesting. The part number Perkins gave me is u5me0031a. The 4 cylinder version of the same bearing is u5me0011a

 

[Kubota Newbie]

Hmmm, been away a long while.
You can go to any reputable automotive machine shop and they'll have a bearing book (or two). Aside from being able to look up the bearing by application you can usually cross from the part number on the original. They'll also usually give you the bore diameter of the rod (or main cap) and the journal diameter so you can be sure what you're ordering is the size you want. For what it's worth, you said you were trying to find .010 "over" bearings. If the crank is worn and being resurfaced what you are really looking for is .010 "under" standard (unless it's been ground once before already). The over-under is referring to the finished journal diameter as compared to std. Very few manufacturers offer "over" rod or main bearings and they are normally quite pricey (BMW used to offer matched over & under rod bearing sets for the old air-head twins, but I can't think of any others other than custom orders).

 

[Kubota Newbie]

Perkins manual indicates maximum amount of undersize grind is -.020 inch for that engine. Std should be 1.612 inches so the minimum allowable rod journal diameter would be 1.593 +/- (assuming no differences in the build specs along the line somewhere as compared to the specs available on-line). Grab yourself a dial caliper and see if you're close to that.

 

[rentthis]

wow! thanks for the info. the existing measurement on the rod journal is 1.609. That's with a cheap caliper but it puts it right on the measurement you provided. That bears out the fact that the company that has been sending me these bearings has been ending the wrong thing. I understand the over/under thing. Everyone around here has always referred to oversized bearings, wrongly, as over. I guess I was just in the habit. yesterday, I found another aftermarket company, thanks to Hudson, that has this bearing in undersized for $45.00 delivered. I had him ship me a set to see if he gets it right.
Thanks again for your input. You obviously have a better understanding of this thing than anyone else with which I have spoken.

Mike

 

[Kubota Newbie]

Brother in law owns automotive machine shop, lets me do my own work there usually so I get free training on all sorts of engine machining operations and ordering accompanying parts.
There ARE of course "oversize" bearings, usually referring to the outside diameter though. Maybe for a cam bore that had to be re-machined or I suppose possibly for a stepped cap rod that was out of round and needed to be honed round again without having the cap ground so it could be re-sized to standard (although a shop manual would probably say to scrap those).
It wouldn't be absolutely necessary... but the shop that is re-grinding your crank would appreciate having the new bearings and rods in-hand. If they're the detail oriented type they'll install a bearing in a rod and torque it to spec so they can measure it and grind & polish the crank so that it is in the middle of the clearance spec.

 

[rentthis]

My guys are all of the above. They won't start without the bearings in hand. My brother in law owns a towing company. He moves everything I need moved but he won't let me drive.