Don't like the look of this.......

[Timleech]

I'd still do the simple magnet test on the debris before getting too despondent.

 

Tim

[monkeyhanger]

I'd still do the simple magnet test on the debris before getting too despondent.

 

Tim

I'm feeling pretty despondent already, Tim, but thanks for providing a (possible) light at the end of the tunnel. Jack

[MtB]

So what exactly IS the 'white metal' used in bearing shells?

 

I've often wondered, and I don't think I've ever noticed it in the Periodic Table

 

 

MtB

[Timleech]

So what exactly IS the 'white metal' used in bearing shells?

 

I've often wondered, and I don't think I've ever noticed it in the Periodic Table

 

 

MtB

 

For diesel engines, it should be an alloy of tin and various other metals, including IIRC Antimony.

Lead based alloys used to be used, possibly still are, though not recommended for the higher stresses in diesels relative to the older petrol engines where they were common.

 

I've got a Hoyt book somewhere which they produced as a guide to poured metal bearings, which details some of the alloys used, but can't lay my hands on it this early in the morning.

 

Tim

[Timleech]

Just to add a couple of web links, these are the people who took over Hoyt:-

 

http://www.ecka-granules.com/en/products/plain-bearing-alloys/

 

and this is a US supplier, which lists actual percentages. The tendency in the US is to refer to 'Babbit metal' rather than 'White metal'

 

http://www.rotometals.com/Babbit-Bearing-Alloys-s/2.htm

 

White metal is also used as a description for some low temperature alloys used for casting models, the modern equivalent of Lead soldiers, I suppose.

 

Tim

[by'eck]

White metal is also used as a description for some low temperature alloys used for casting models, the modern equivalent of Lead soldiers, I suppose.

 

Tim

And in jewelry apparently.

[martyn 1]

No need to get to dispondent to quickly. Just get methodical and work out where it came from. metalic bits floating around is not a good thing and ignoring it would not be a good idea. We have had to deal with the result of that too many times. Like Tim has mentioned try and identify what materials the bits are. if they are non magnetic and obviously not brass then you are most likely looking at white metal from a bearing or possibly aluminium from a piston if its picked up but less likely. if it is magnetic or brass then it will steer you down a different route.

 

If there was sufficent amount to cause you concern and it is non magnetic/looks like white metal then I would check the crank bearings just to be make sure as if you catch it soon enough it isnt going to be to detrimental other than the inconvienience of doing the work. but ignore it and you may well cause irrepairable damage to the rest of the engine. We have had a JP3M that the owner ignored low oil pressure on for so long, by the time we stripped it the once standard crank had to be ground to maximum undersize because of the damage that had been caused by using it like this. I have also rebuilt more than one JP2 that has snapped its crankshaft caused by excessive play in the main bearings and as they have no centre main they dont like excessive play.

 

I also wouldnt follow the "my engine has only done low hours over the last x years so should be fine route" as depending on how they are stored we have had a fair few JP's that have known hours "400 or less" since new (backup generators etc) and on stripdown the bearing surface had pretty much crumbled away.

 

Check it out sooner rather than later and it soundn't cause to many dramas.

Edited November 23, 2014 by martyn 1

[monkeyhanger]

No need to get to dispondent to quickly. Just get methodical and work out where it came from. metalic bits floating around is not a good thing and ignoring it would not be a good idea. We have had to deal with the result of that too many times. Like Tim has mentioned try and identify what materials the bits are. if they are non magnetic and obviously not brass then you are most likely looking at white metal from a bearing or possibly aluminium from a piston if its picked up but less likely. if it is magnetic or brass then it will steer you down a different route.

 

If there was sufficent amount to cause you concern and it is non magnetic/looks like white metal then I would check the crank bearings just to be make sure as if you catch it soon enough it isnt going to be to detrimental other than the inconvienience of doing the work. but ignore it and you may well cause irrepairable damage to the rest of the engine. We have had a JP3M that the owner ignored low oil pressure on for so long, by the time we stripped it the once standard crank had to be ground to maximum undersize because of the damage that had been caused by using it like this. I have also rebuilt more than one JP2 that has snapped its crankshaft caused by excessive play in the main bearings and as they have no centre main they dont like excessive play.

 

I also wouldnt follow the "my engine has only done low hours over the last x years so should be fine route" as depending on how they are stored we have had a fair few JP's that have known hours "400 or less" since new (backup generators etc) and on stripdown the bearing surface had pretty much crumbled away.

 

Check it out sooner rather than later and it soundn't cause to many dramas.

Thanks for the response. I'm going to try to find time to drop the big ends at the weekend, then I'll have some idea of what I have to do, and how deep my hand will have to go in my pocket! Jack

[Southern Star]

So what exactly IS the 'white metal' used in bearing shells?

 

I've often wondered, and I don't think I've ever noticed it in the Periodic Table

 

 

MtB

It used to be known as "monkey metal" but now seems to be called "pot metal"

 

http://en.wikipedia.org/wiki/Pot_metal

[boathunter]

Nobody has mentioned the aluminium powder...

 

I had a case with ali powder and similar debris (completely diffent type of engine) and someone had put both circlips in a piston at the same end of a gudgeon pin. You can imagine the damage. It was a vehicle that managed 500 miles before conking out.

 

I can't remember ever hearing of one spontaneously breaking though.

[Timleech]

It used to be known as "monkey metal" but now seems to be called "pot metal"

 

http://en.wikipedia.org/wiki/Pot_metal

 

That's the other sort of white metal, not the stuff used for bearings.

 

Tim

[Southern Star]

"White metal" is a generic term for low melting point metal alloys of varying composition.

[RLWP]

Not in my world it isn't. Mazak is low melting point, is what I know as Monkey Metal and was used for diecasting

 

The whitemetal used to line bearing shells is a completely different thing

 

Richard

[Timleech]

Not in my world it isn't. Mazak is low melting point, is what I know as Monkey Metal and was used for diecasting

 

The whitemetal used to line bearing shells is a completely different thing

 

Richard

 

Confusingly, though, Mazak is also a brand of computer control for machinery. For this reason, I suppose, in the US the metal is known as Zamac (or Zamak). It's an alloy of Z inc, Aluminium, Magnesium and Copper

 

 

Edit, to reiterate, White metal for bearings is an alloy based on either tin or lead, neither of which appears in Mazak/Zamak/Pot metal/Sh*t metal, call it what you will.

 

Tim

Edited December 16, 2014 by Timleech

[Proper Job]

Only just picked up on this thread

 

The exact same symptoms the OP has described was the initial reason for inspecting my mates JP

 

It resulted in this:

 

 

A trip down the tow path with the crank and rods off to the machine shop for a regrind and new main and big end bearings

 

Hope your inspection goes well

[monkeyhanger]

If I do that and get the oil analysed, what will it tell me? That I've got bearing particles in the oil? I have saved some of the flakes, but I'm no wiser.

Perhaps I should pull the big ends and have a look.

Thanks to everyone who replied to my original post. You certainly gave me something to think about, and I feel it's only right that I give you an update.

Yesterday I eventually got round to removing the big end bearings to have a check. Although the shells were worn, there is still some life left in them. However I did notice a small groove cut out of the leading edge of each shell which showed exposed copper. I think this is almost certainly where the particles of white metal in the sump have come from, and it has been caused by the bearing shell contacting the crankshaft.

Using a length of 3x2 wood behind the flywheel I checked for " fore-and-aft" movement. Martin ,who contributes on here, reckoned on 6 thou max. My dial gauge showed 21 thou! Using a mooring pin under the flywheel pulley showed 15 thou of up and down movement.

So, it's bite the bullet time and rebuild the bottom end (at least). However, I'm not able to do it myself anymore due to lack of facilities and excess of years. I seem to have two choices----try to persuade an engineer I know not too far from London (where the boat is) that he'd love to do the job for me, and arrange a tow to his yard, or to reassemble the big ends and sail the boat to an engineer in the Midlands who has been recommended to me. Either way, not an ideal scenario.

I'll post an update when I have more info. Jack

[Proper Job]

Oh dear

 

Unfortunately time to get the wheel barrow out (and the cheque book )

 

A bottom end rebuild is not for the light hearted. There's some seriously heavy lumps of metal that need to be lugged about

 

Good luck. You know it will be worth it in the end.

[monkeyhanger]

Oh dear

 

Unfortunately time to get the wheel barrow out (and the cheque book )

 

A bottom end rebuild is not for the light hearted. There's some seriously heavy lumps of metal that need to be lugged about

 

Good luck. You know it will be worth it in the end.

Yes, I know just how heavy they are, believe me. I bought the engine as a pile of bits and rebuilt in in my front garden under a tarpaulin about 25 years ago. The neighbours were very interested when it first fired up with no silencer, I can tell you! I then borrowed a trailer and took it up to Birmingham to have the boat shell built around it. If I could get it back to my front garden, I'd do it again, but I have no facilities for removing it from the boat, and it's not a job I fancy doing in the confines of an engine 'ole, I'm afraid.

[monkeyhanger]

Yes, I know just how heavy they are, believe me. I bought the engine as a pile of bits and rebuilt in in my front garden under a tarpaulin about 25 years ago. The neighbours were very interested when it first fired up with no silencer, I can tell you! I then borrowed a trailer and took it up to Birmingham to have the boat shell built around it. If I could get it back to my front garden, I'd do it again, but I have no facilities for removing it from the boat, and it's not a job I fancy doing in the confines of an engine 'ole, I'm afraid.

An update on this story.................

My engine is now in pieces, with the crankshaft and bearings in the workshop. It appears that the pieces of white metal I found in the sump were from the "middle" main bearing (ie the forward part of the rear main bearing) This has started to break up and has quite a large number of chunks missing.

Finding parts is not easy! I need a front main bearing and a middle main bearing. My crankshaft is 10 thou undersize, and doesn't need regrinding, but if someone came up with a 20thou under set of bearings, it would get a regrind.

There is a waiting time of several months if I choose to have them remetalled.

Can anyone out there point me in the direction of bearings, either 10 or 20 thou under, please? Jack

[RLWP]

Sue will do a stock check for you tomorrow

 

Richard

[monkeyhanger]

An update on this story.................

My engine is now in pieces, with the crankshaft and bearings in the workshop. It appears that the pieces of white metal I found in the sump were from the "middle" main bearing (ie the forward part of the rear main bearing) This has started to break up and has quite a large number of chunks missing.

Finding parts is not easy! I need a front main bearing and a middle main bearing. My crankshaft is 10 thou undersize, and doesn't need regrinding, but if someone came up with a 20thou under set of bearings, it would get a regrind.

There is a waiting time of several months if I choose to have them remetalled.

Can anyone out there point me in the direction of bearings, either 10 or 20 thou under, please? Jack

We now have the bearings required to rebuild the engine, so that at least, can go ahead. However, it appears now that the gearbox is in very poor condition. It desperately needs a set of planetary gears, and the man who is rebuilding the engine has exhausted his list of suppliers. The gearbox COULD go back together as it was, but how long it would last, and how noisy it would be would be anybody's guess. To my mind, that would not be a sensible thing to do.

If anyone out there knows where I might track down some gears, new or second hand, or even a complete gearbox, I'd be eternally grateful.

 

Also, I've been told that the gears from a 3G gearbox ( I think that's the one- the next size up from mine) could be used, after a bit of machining. Any thoughts?

[martyn 1]

We now have the bearings required to rebuild the engine, so that at least, can go ahead. However, it appears now that the gearbox is in very poor condition. It desperately needs a set of planetary gears, and the man who is rebuilding the engine has exhausted his list of suppliers. The gearbox COULD go back together as it was, but how long it would last, and how noisy it would be would be anybody's guess. To my mind, that would not be a sensible thing to do.

If anyone out there knows where I might track down some gears, new or second hand, or even a complete gearbox, I'd be eternally grateful.

 

Also, I've been told that the gears from a 3G gearbox ( I think that's the one- the next size up from mine) could be used, after a bit of machining. Any thoughts?

Choices would be to get a gear company to make some, so you have brand new. track down some NOS ones. or I do have a number of complete used gearboxes but wouldn't be sure that the bits you need were any better than what you have.

 

Interestingly the parts lists I have here lists that all parts are common for both 2 & 3 cylinder boxes except for the input gear that attaches to the crank. (The two engines have a different size taper) X87 -11141 and X87-11131. 2 of each.

[RLWP]

Likewise, we almost certainly have a set of gears in one of the stillages

 

Richard

[BEngo]

Worth talking to HPC gears- they will want to look at the old ones, but they are happy to do one-offs and I know they have in the past made a set of Kelvin J timing gears at reasonable cost.

 

 

http://www.hpcgears.com/n/left_menu/custom_parts/custom_parts.php

 

 

N

[frangar]

Google Llewellins gears in Bristol. Did a fab job on my 3G and reduction box. Wasn't cheap tho. Great guys to deal with and a day out in itself looking round their premises.

 

Cheers

 

Gareth.