Mysterios metal in oil sump

[CHRISEEBOY]

Hello everyone.

I have recently aquired my very own JCB 3C mk3. I removed the oil sump in order to replace the gasket and to my horror I found several strange pieces of metal. They are all the same more or less and a few look a bit chewed up, I'm hoping someone might have some idea what they are? They are a yellowish metal so im presuming brass. They each have a small silver pin running through them and two of them are actually connected together with a pin. Could they have oringinally been one large piece, some sort of cog? Where could they have come from?

Thank you in advance for your thoughts.

[gecko.cx]

Ooooo - nasty.
Pretty sure it's a bearing cage. It doesn't do much in it's own right, but keeps the balls (of a ball bearing) evenly spaced.
Ignoring the metal going around, the offending bearing is no longer supporting its shaft.

https://www.rmbearings.co.uk/pictures/p ... 0TYPES.pdf

[Jeremy Rowland]

Hi Chris and welcome as Ian states these parts do look like parts of a bearing cage; please forgive my ignorance here but you say you removed the oil sump, I am assuming this is the transmission sump and not the engine sump? The reason I say this is that to my knowledge there would not normally be any bearings of that type in an engine on that machine (that I can think of)

Jeremy

[CHRISEEBOY]

Hi chaps, thank you for your swift responses. I can confirm that we are talking about the main engine sump of a leyland 4/98NT. The JCB was running as it should when I bought it but when it arrived on the low loader the guy started it up and about 2minutes later it stalled and he couldnt start it up again. He had to pull it off the low loader with another JCB! Since then I have had the engine apart, head off, sump off etc. The big end on cylinder #1 had welded its self to the crank. New bearing shells on and crank polished back to chrome. Just putting it back together now but very worried about the metal in the sump. A bearing cage you say? As in ball bearings not bearing shells? Will the engine run ok without it? Looks like it had been there long before the engine sieze...

[Slooby]

It certainly looks like a two piece brass bearing cage from either a roller or ball bearing race. Quite what it's doing in the engine sump is a real mystery because the only things engine related likely to use a ball/roller bearings are the oil and water pumps, and I can't see how either of them could deposit their bearings into the sump without some massive block failure! That is unless of course there is a drive that comes off the crank for the hydraulic pump of course...

[essexpete]

Someone on the farming forum wondered if it could be from the balancer unit although I thought the Power train may not have had a balancer? I know some got into problems putting a truck based unbalanced engine in the fixed frame skids.

[Jeremy Rowland]

Hi chaps, thank you for your swift responses. I can confirm that we are talking about the main engine sump of a leyland 4/98NT. The JCB was running as it should when I bought it but when it arrived on the low loader the guy started it up and about 2minutes later it stalled and he couldnt start it up again. He had to pull it off the low loader with another JCB! Since then I have had the engine apart, head off, sump off etc. The big end on cylinder #1 had welded its self to the crank. New bearing shells on and crank polished back to chrome. Just putting it back together now but very worried about the metal in the sump. A bearing cage you say? As in ball bearings not bearing shells? Will the engine run ok without it? Looks like it had been there long before the engine sieze...

Ahh thanks Chris; right then, years ago now, as an apprentice mechanic working on trucks, the fitter who I was working with got me to drain the oil on a Rolls Royce Eagle Diesel engine, as I took the sump plug out I heard a distinctive 'plop' as something dropped into the draining oil, I put my hand and arm (should not really ever do this) into the oil and pulled out a chunk of gear tooth.
To cut a very long story short the gear tooth was not from any of the gear teeth in that engine; the only way it could have got in was that the engine must have been topped up with a can oil with contaminated bits in it, either that or it was deliberately put in there to sabotage the engine.

This was why I asked about what the sump was from, now I know it would appear that these bits are foreign (as in they are not part of your engine) and they have either been put in there deliberately or accidentally; the one piece of advice that I would offer to you is to ensure that all of the engines oil galleries and oil ways are free from any other metallic debris including the crankshaft before you put the whole thing back together, you don't want it going bang after much time and expense.

The only engines that I know of that use roller bearings are some older large Kawasaki motorcycles (old Z1000 main bearings) some smaller two stroke ones and Maybach engines (Tiger tank vintage and diesel loco) so it's very rare to find an engine that has it's main bearings as roller balls.

Jeremy

[CHRISEEBOY]

Well its reasuring to know that they are foriegn objects, thanjs Jeremy. Like I said, the engine was working fine but they guy i purchased it from obviously didnt want to shell out £20 for some oil prior to selling it. When I dropped the sump plug I caught 1.8L of oil and I belive it takes 9L. Even if there was a liter or two still clinging to the engine or trapped in the oil filter, it was dreadfully low hence the engine sieze. Everything is back on now, apart from rocker cover and oil sump. I gave it a 1 second turn over using the starter motor and the valves danced up and down nicely without any horrible sounds! I think that metal has been in there some time, it was all right at the bottom of the sump, underneath a kind of plate that sits inside tge sump just above the plug. If i hadnt completely cleaned out the whole sump I'd have missed them.

Thanks for all your input, i think we can put this thread to bed now.

[Slooby]

The only engines that I know of that use roller bearings are some older large Kawasaki motorcycles (old Z1000 main bearings) some smaller two stroke ones and Maybach engines (Tiger tank vintage and diesel loco) so it's very rare to find an engine that has it's main bearings as roller balls.

Lots of two strokes run roller bearings, and Honda loved needle roller bearings on some of their 4 strokes, but I think we're all in agreement that Leyland heavy diesels are somewhat unlikely to have anything as sophisticated as that inside them

It does begger belief how abusive some people can be when it comes to maintaining equipment and the time they will spend on bodging something up for the want of ordering a cheap replacement part...

[CHRISEEBOY]

It certainly looks like a two piece brass bearing cage from either a roller or ball bearing race. Quite what it's doing in the engine sump is a real mystery because the only things engine related likely to use a ball/roller bearings are the oil and water pumps, and I can't see how either of them could deposit their bearings into the sump without some massive block failure! That is unless of course there is a drive that comes off the crank for the hydraulic pump of course...

Slooby, you mentioned a drive for the hydraulic pump... well there is a prop shaft coming straight off the main crank pully that connects to the hydraulic pump via two CV joints. How is this related to the broken bearing cage in the oil sump?