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Not sure if I would regularly put that in a narrow boat engine unless I was sure it was really well run in or was in an area where I would normally run at high seed and power very regularly.. It seems to have  a CL API rating that suggests to me that it may be synthetic or have a high anti-friction component.

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29 minutes ago, Tony Brooks said:

Not sure if I would regularly put that in a narrow boat engine unless I was sure it was really well run in or was in an area where I would normally run at high seed and power very regularly.. It seems to have  a CL API rating that suggests to me that it may be synthetic or have a high anti-friction component.

To be honest Tony I have never found any oil as being unsuitable for a diesel engine especially something manufactured over 20 years ago.

I have run engines on generators flat out on the cheapest muck and on the finest synthetics now available and have not had any problems.

A plant engineer of my acquaintance agrees with me as he runs any engine on recycled  cheap oil, Yanmars, Mercedes, JCBs, Komatsus, Kubotas, Isuzus, Hyundais etc.

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21 minutes ago, Tracy D'arth said:

To be honest Tony I have never found any oil as being unsuitable for a diesel engine especially something manufactured over 20 years ago.

I have run engines on generators flat out on the cheapest muck and on the finest synthetics now available and have not had any problems.

A plant engineer of my acquaintance agrees with me as he runs any engine on recycled  cheap oil, Yanmars, Mercedes, JCBs, Komatsus, Kubotas, Isuzus, Hyundais etc.

 

It is not the cheapness that gives me some concern, it is the potential for excess friction  reducers for a lightly loaded engine.

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40 minutes ago, Tony Brooks said:

 

It is not the cheapness that gives me some concern, it is the potential for excess friction  reducers for a lightly loaded engine.

OK, I'll buy that there are friction reducers aplenty in a synthetic oil. As there are in any multigrade.  So why don't we still just use monograde oils? >specially in engines designed and made before even multigrades were invented.

But reducing friction is good, yes?  So more friction reduction is better?

Just what difference does it make especially to a lightly loaded engine as in a canal boat?

Are we talking about the mythical bore glazing? I always thought this was due more to low piston temperatures than anything else.

I have thrashed engines for days unmercifully on compressors and generators and run slow diaphragm pumps for months all on the same oils of any type or specification and not noticed any differences.

Edited by Tracy D'arth
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46 minutes ago, Tracy D'arth said:

I have run engines on generators flat out on the cheapest muck and on the finest synthetics now available and have not had any problems.

 

 

My F-i-L who back in the day was a Chartered Engineer at BP specialising in lubricants used to say much the same. Pretty much any ol' muck that says "Oil" on the tin is infinitely better than no oil at all, and not to worry too much about it!! 

 

He also used to say the additive pack in Woolworths brand oil made it as good as any of the full priced major brands of oil even though it sold for half the price. And the same about Tesco brand oil too IIRC.

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Most people would say that the flat out running is good, its the light load running that upsets diesels. I think bore glazing is a real issue, not mythical, though modern engines appear to suffer less. Having talked to a well known oil company about this, they certainly indicated that additives are a factor. Its hard to get definitive answers but I suspect that low temperature running causes one of the additives to misbehave.

 

I used to own an old VW camper and folklaw said always use a monograde, though its not the mono (rather than multi) that is important, monogrades are favoured because they contain no (or fewer?) additives.

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33 minutes ago, dmr said:

Having talked to a well known oil company about this, they certainly indicated that additives are a factor. Its hard to get definitive answers but I suspect that low temperature running causes one of the additives to misbehave.

 

Had a long chat the other day with a bod with an old JD3 that didn't smoke, not even a bit. He said he's been advised long ago the trick was to use cheap, no-name oil with no or few additives, and it seemed to have worked for him. 

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1 minute ago, MtB said:

 

Had a long chat the other day with a bod with an old JD3 that didn't smoke, not even a bit. He said he's been advised long ago the trick was to use cheap, no-name oil with no or few additives, and it seemed to have worked for him. 

 

I think I've shared a few locks (and beers) with him. I would really like to find out why his engine is smoke free, most JD3's are a bit smokey at light load but not his.

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Oil ,at the moment , is quite expensive . As are many things 

 

I like Shell Rimula R4X . I don't like the price shown below  much. I paid £71 earlier in the year.

image.png.6077e0f902f2f50f016ce9109e76a097.png

 

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10 hours ago, dmr said:

Having talked to a well known oil company about this, they certainly indicated that additives are a factor. Its hard to get definitive answers but I suspect that low temperature running causes one of the additives to misbehave.

 

That is my understanding as well. I think we have to be careful with phrases like low temperature because I fear many readers will think of the temperature on the gauge whereas I understand it, it is to do with low cylinder wall temperature and, as Tracy said, low piston temperature.  A piece Lister sent me also sited fuel as a contributory factor to glazing, but I think that was in relation to huge engines that burn a very different fuel to our diesel, and also the shape of the piston crown (possibly the degree of taper). Note for our less technical readers. Pistons are not perfectly cylindrical. They are both oval in section and tapered when cold so when hot and expanded they fit the bore properly.

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54 minutes ago, Tony Brooks said:

 

That is my understanding as well. I think we have to be careful with phrases like low temperature because I fear many readers will think of the temperature on the gauge whereas I understand it, it is to do with low cylinder wall temperature and, as Tracy said, low piston temperature.  A piece Lister sent me also sited fuel as a contributory factor to glazing, but I think that was in relation to huge engines that burn a very different fuel to our diesel, and also the shape of the piston crown (possibly the degree of taper). Note for our less technical readers. Pistons are not perfectly cylindrical. They are both oval in section and tapered when cold so when hot and expanded they fit the bore properly.

Totally irrelevant to the topic but the piston in my Farrymann generator is so  tapered that it cannot be removed through the top of  the block 

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Bore glazing is pretty common in small aircooled Lister,Petter,and Hatz diesels on small gensets ....from 2 to 7 kva .......its caused by running the engine near unloaded,with say one 100 watt lightbulb on.............typical results of bore glazing are badly worn rings,much smoke,poor compression ,and finally the engine runs out of oil and seizes,if it doesnt have an oil sentry...............Glazing is quite easily cured by honing the bore and fitting new rings.

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15 minutes ago, john.k said:

Bore glazing is pretty common in small aircooled Lister,Petter,and Hatz diesels on small gensets ....from 2 to 7 kva .......its caused by running the engine near unloaded,with say one 100 watt lightbulb on.............typical results of bore glazing are badly worn rings,much smoke,poor compression ,and finally the engine runs out of oil and seizes,if it doesnt have an oil sentry...............Glazing is quite easily cured by honing the bore and fitting new rings.

Have you ever found the mechanism for bore glazing?  Is it due to cool running pistons due to light loading? Or is there another cause?

I fail to see how any oil could  cause bore glazing by itself, there must be an underlying factor which is manifested by light running for long periods. 

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1 hour ago, Tracy D'arth said:

I ail to see how any oil could  cause bore glazing by itself, there must be an underlying factor which is manifested by light running for long periods. 

 

I don't think the actually causes the bore glazing but a combination of the reaction of certain additives, the oil itself, and cool cylinder/piston temperatures react so that instead of burning the residual film of oil on the bores to ash it cooks it to a sort of varnish. (a bit like boiling linseed oil) that then gets smeared over the bores and filling the honing marks. Once again, that is as I| understand it, so I may be wrong. It is very difficult to find anything definitive about it, but I know from  reports from Southern Gas Board vehicle  mechanics their J4 vans with 1.5 diesels in them suffered from it badly and the investigation concluded that the on call gas engineers sat in the cabs for hours with the engine idling to help keep the heater blowing warm air. So back to light load running and cool cylinder wall/piston temperatres.

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6 hours ago, john.k said:

Bore glazing is pretty common in small aircooled Lister,Petter,and Hatz diesels on small gensets ....from 2 to 7 kva .......its caused by running the engine near unloaded,with say one 100 watt lightbulb on.............typical results of bore glazing are badly worn rings,much smoke,poor compression ,and finally the engine runs out of oil and seizes,if it doesnt have an oil sentry...............Glazing is quite easily cured by honing the bore and fitting new rings.

 

Is this a ten minute job or should I set aside a full half hour ? 😀

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I spoke to an an "expert" to find which of the oils that his company sells would be best for a lightly loaded diesel in a narrowboat. There were two possible oils, both 15:40 CG4 (I think).  He said, use this one, don't use the other one as the additives are much more likely to cause bore glazing.

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2 hours ago, dmr said:

I spoke to an an "expert" to find which of the oils that his company sells would be best for a lightly loaded diesel in a narrowboat. There were two possible oils, both 15:40 CG4 (I think).  He said, use this one, don't use the other one as the additives are much more likely to cause bore glazing.

Please can you quote which oils and if possible which additive it is causing this problem?  There are hundreds of boaters who need to know.

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7 hours ago, Tony Brooks said:

.......  a combination of the reaction of certain additives, the oil itself, and cool cylinder/piston temperatures react so that instead of burning the residual film of oil on the bores to ash it cooks it to a sort of varnish. (a bit like boiling linseed oil) that then gets smeared over the bores and filling the honing marks. 

That sounds consistent with the user handbook and official  workshop manual for the Hillman Imp I used to have, which advised you to drive away promptly after starting the engine and not to leave it idling.  You were also advised not to use friction-reducing additives like Molyslip (molybdenium disulphide-based) on new or rebored engines. Friction between the rings and the bores was essential to bedding-in, and the friction-reducing additives would have prevented this from taking place. 

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5 minutes ago, Tracy D'arth said:

Please can you quote which oils and if possible which additive it is causing this problem?  There are hundreds of boaters who need to know.

I don't know which additive is the culprit, I have tried to find out but its not easy.  I don't know how expert the expert who I spoke to was. I think the outcome was that the "mixed fleet" lubricants are a safer bet than the "high performance diesel specific" oils, and I suspect it is a bet rather than a done deal.. What is interesting is that two oils that meet the same API specs can have significantly different additive packs.,  

From my www searches I started to think that an anti-wear additive might be to blame but it was far from conclusive.

 

I doubt that hundreds of boaters want to know, its a handfull at most, the majority of boaters just like cheap.😀

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1 hour ago, dmr said:

I doubt that hundreds of boaters want to know, its a handfull at most, the majority of boaters just like cheap.😀

 

 

Which paradoxically is probably why they are not interested, because using the cheapest of cheap oils seems (anecdotally) to be the most likely to result in the absence of bore glazing. 

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Here is a write up on bore glazing if it is any interest. It is talking about generating sets but that makes little difference as it is the low load factor that seems tocause the problem.

Screenshot_20220513-075914_Chrome.jpg

Screenshot_20220513-075906_Chrome.jpg

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Bore glazing is supposed to be caused by partially burnt diesel fuel clogging all the honing marks in the bore.......Its a magic way of buying little diesel gensets for scrap price,zero compression equals zero dollars......toss in a set of rings,and a hone, youve got a $3000 genset......They still love the Lister name.,provided its a UK made one .....

Edited by john.k
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