Running In

Hi all, Nick's recent Norman post mentioned Rocol running in paste, which triggered a memory.

In a long forgotten SEM article someone was praising a particular abrasive compound used to bed-in new rings. It had the useful property of starting off quite coarse and becoming finer as the running in progressed, eventually becoming more or less inactive.

The question is has anyone used it? Is it any good? Where do I get some? Other suggestions (polite!) would be gratefully received.

The falteringly flatulent rhythm from my re-ringed Bamford 4hp indicates that it needs some help, laxative or anti-rejection pills to allow it to accept the new rings!

Regards, Arthur G

Reply to
Arthur Griffin & Jeni Stanton
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I've got some of the stuff in question, its a fine green powder which is mixed with oil, and then applied to the cylinder or whatever. I'll have a look in the shed tomorrow night. It does what it says on the bottle, and I have found it to be very useful over the years. It enabled me to get enough compression in the Ransomes Wizard to start it up initially when all else had failed.

Regards

Philip T-E

P.S I assume you did hone or glaze bust the Bamford bore before fitting the new rings?

Reply to
ClaraNET

said ... I assume you did hone or glaze bust the Bamford bore before fitting the new

Yup.

Regards, Arthur G

Reply to
Arthur Griffin

The Rocol (mt-lm?) paste is a moly anti galling compound. I use it in places which are likely to be poorly lubricated, particularly on start up, like little end bearings valve stems and cam followers. I wouldn't use it on the bore though, probably more likely to prevent the rings bedding in there. I once made that mistake with a freshly rebuilt Imp (car) engine. I thought I'd be kind to it and put Molyslip in the oil - don't think I ever managed to run it in, it was still burning oil 10,000 mile later!

Not come across abrasive compound you mention, what stops it embedding in soft bearing materials and turning them into laps?

Reply to
Nick Highfield

I would certainly be aware of this possibility. It may be that the abrasive is designed to be used in a more modern engine with filtered oil system so that the bearings are protected by the filter. An old design without a filter could suffer.

John

Reply to
John Manders

Thre are two varieties of the compound, one for hard metals and one for soft metals. I used the hard metal one and it seems to be fine, it breaks down very quickly, in a matter of minutes, but does an excellent job.

Regards

Philip T-E

Reply to
Philip THornton-Evison

Good points, but I'm hoping that in a drip-fed total-loss oil system, such as the horizontal Bamford, all that would be needed would a good clean of the bore, piston and valves. The small end is a worry I agree, though if I double the oil feed rate it should be kept clear of abrasive muck. The big end and mains are separately lubed, so no problem there.

My plan was to smear this goo on the upper part of the bore.

Regards, Arthur G

Reply to
Arthur Griffin

Ah, open crank engine, I was thinking of enclosed splash or pump lubricated. I imagine it would indeed be a fairly simple matter to keep the stuff away from anywhere where it might do more harm than good.

P T-E, How's it used, do you apply and run engine or work piston in bore by hand, how did you keep 'hard metal' compound from getting anywhere it didn't ought in Rancid Wizard, or is it that benign that it doesn't matter?

Reply to
Nick Highfield

I think I would be very wary of putting anything abrasive into the engine deliberately.

I have seen the claims and the adverts and also Philip's article re the Wizard, but it seems to me that it is a substitute for what used to be a running-in period. and it will always be in there, albeit getting smaller in particle size (for those particles that run through the bearings etc)

I'm not personally happy to use the stuff, but that's my own opinion.

Peter

Kind regards,

Peter

Peter Forbes Prepair Ltd Luton, UK email: snipped-for-privacy@easynet.co.uk home: snipped-for-privacy@easynet.co.uk

Reply to
Prepair Ltd

You just mix the powder into a paste with lubricationg oil, and then apply it to the afflicted parts :-) Don't need to use very much at all. For a cylinder bore, after the compound has done its work, I wipe the bore out with a clean rag, then flood it with oil and turn the engine over a few dozen times, then clean the bore again. As I said, its never caused any problems for me at all, it breaks down quickly and appears to be completely benign.

Regards

Philip T-E

Reply to
Philip THornton-Evison

The product is called Timesaver Lapping Compound and it used to be advertised in Model Engineer - there was a full article about it a few years ago.

The distributor in 1998 was

GA Watt Engineering Supplies

375 Hunts Pond Road Titchfield Common Hants Tel : 01329 843022

No guarantee that they are still there.

My experience with it was bedding in a the big bearing on my Wolseley WD2 after an adjustment - worked a treat.

In message , Philip THornton-Evison writes

Reply to
John Ambler

Thanks, John, for the product name.

For those interested

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gives some more information.

As I have never scraped bearings and have some to do, the soft compound for bearings sounds interesting, especially after the Wolseley bearing testimonial.

Regards,

Arthur G

Reply to
Arthur Griffin

I like their home page, especially the multilingual bit where you can get "Translations by Babel Fish" Obviously a hitch hiker.

John

Reply to
John Manders

John, Nice to see there are a few other hikers about. Babel fish is a translation service from Altavista, the once pre-eminent search engine, so now you don't have to put the fish in your ear!

It was a great shame Douglas Adams died young, I used to enjoy his output tremendously.

Regards, Arthur G

Reply to
Arthur Griffin

You know I said a while ago that I could not remember the last time I read a work of fiction? (may have been off list) - Well that was probably it!

Reply to
Nick Highfield

Me too. I met the programme when I went into the workshop one afternoon, to work on my (then newly acquired) Amanco to hear "The Hitch hikers guide to the Galaxy" announced on the radio which is always set on Radio 4. First airing, first performance - pure serendipity!

Regards,

Kim Siddorn.

"When three or more are involved, the culprit will frequently escape punishment"

Laws of Hammurabi, 1780BC

Reply to
J K Siddorn

Deliberatrly introducing abrasive materials into an engine sounds wrong to me.

Is there any reason why you cant use some straight mineral oil in the sump, warm the motor to operating temperature and then rig something up to it so you can run it at around 3/4 speed and full load for 15-20 mins.

The reason why running in a newly rebuilt / bored engine fails and you end up with massive oil consumption / poor compression is because its never run under enough anger to bed the rings in.

tim..

Reply to
Tim (Remove NOSPAM. Registry corupted, reformated HD and l

It sounds all wrong to me as well, but at the time I needed desperate measures to get the Ransomes Wizard to run. Since then I have found the stuff very useful to have about the workshop, and it does materially help in bedding rings in on an engine that won't have to work hard for its living.

Regards

Philip T-E

Reply to
ClaraNET

I've not used this stuff in years, but I did have a Honda CB125 once , bored out to about 160 odd cc with a CB750 piston in it. The liner was only a few thou thick in the skirt (you could flex it with your thumbs!) and whether it was that I don't know, but it smoked badly after I'd put it together and my tame rebore man gave me some of this stuff and a new gasket set in lieu of warranty!

His instruction was to rub it around the rings and grooves as " it will bed the rings in quickly (fifty miles) and the centrifugal crank flinger will ensure it never reaches the bearings."

He was - is still- a pretty canny machinist and engineer and it certainly worked on this bike, our much thrashed works hack. George and I used it for shopping when I had the bike shop and as we'd ported, valved and recarbed it with second hand bits, it went like pig poo off an oily shovel ;o)). George took it on after a couple of years and it was still going when we closed the shop and I lost track of him.

Regards,

Kim Siddorn.

"When three or more are involved, the culprit will frequently escape punishment"

Laws of Hammurabi, 1780BC

Reply to
J K Siddorn

I heard the first series too. I was expecting something on astronomy!

Reply to
Andy Dingley

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