Glazed Bores

[Old Son]

Having read many posts suggesting that running an engine in idle to charge the batteries could cause glazing of the bores, I wrote to Beta asking them if this was an issue. Their response was that provided the correct grade mineral oil was used then glazing of bores would not be an issue. They confirmed that putting the boat into gear to lightly stress the engine whilst moored was not required.

 

Thought I would pass on this information, it might even save some erosion of the canal.

Edited January 6, 2010 by Old Son

[mrsmelly]

Having read many posts suggesting that running an engine in idle to charge the batteries could cause glazing of the bores, I wrote to Beta asking them if this was an issue. Their response was that provided the correct grade mineral oil was used then glazing of bores would not be an issue. They confirmed that putting the boat into gear to lightly stress the engine whilst moored was not required.

 

Thought I would pass on this information, it might even save some erosion of the canal.

 

Got to agree

My Beta is run daily to supply all my lektric needs. About 4000 hours now and still sweet, never a puff of smoke never a drop of oil used. I think glazing of bores is possible on older units but doubt if anyone uses old engines now why would you

[Giggetty]

Got to agree

My Beta is run daily to supply all my lektric needs. About 4000 hours now and still sweet, never a puff of smoke never a drop of oil used. I think glazing of bores is possible on older units but doubt if anyone uses old engines now why would you

 

I have read that glazing in older engines may occur with the wrong type of oil, specifically CF etc instead of CC or CD

[RLWP]

Having read many posts suggesting that running an engine in idle to charge the batteries could cause glazing of the bores, I wrote to Beta asking them if this was an issue. Their response was that provided the correct grade mineral oil was used then glazing of bores would not be an issue. They confirmed that putting the boat into gear to lightly stress the engine whilst moored was not required.

 

Thought I would pass on this information, it might even save some erosion of the canal.

 

Not only will it save erosion, it will stop you breaking the BW bye-laws too.

 

Richard

[alan_fincher]

All about right, I think.

 

Some older engines seem to have earned a reputation for it.

 

The BMC 1500s and 1800s are often quoted as likely "bore glazers" if run off load for battery charging, but I don't know how valid that is.

 

There is also a strong suggestion that using the specified API-CC oil in such engines can help minimise, although others argue vehemently that that is nonsense.

 

As has been previously discussed, it is certainly the case with some of the modern marinised Japanese industrial units that the API spec of the oil recommended by the mariniser is lower than what would be the case if the same engine were not in "marine" use, (can't remember for certain which, though).

 

Although we seldom run our engine (BMC 1800) for anything other than going along, (albeit that heat and electricity are also produced as a result), I still heed the advice about sticking to an API-CC oil, as I'm not expert enough to be sure myself, so might as well err on the side of caution.

 

Struggling to find reasonably priced 20W-50 API-CC oils, at the moment though, without resorting to the extra costs of mail ordering. Chandleries don't seem to routinely stock a 20W-50, or at least not ones I've been to recently.

[Timleech]

I've just checked the wording of the Lister H series manual, which seems to have been written when CD was the highest detergency spec readily available!

 

From the horse's mouth, so to speak, for the doubters:-

 

To paraphrase, it specifies a minimum spec of API-CC, and CD for turbocharged engines. It also says CD can be used with advantage in heavily-worked naturally-aspirated engines but to stick to CC for new/newly reconditioned engines and for those which are not heavily worked because using CD can 'inhibit running-in, and give rise to bore glazing in engines operating on low duty cycles'

 

Normal canal pleasure boat operation can certainly be regarded as low duty cycle for most of the engines used.

Note that the reply from Beta said 'provided the right grade of oil was used', so take care to stick to their recommendation, for instance if they say use a CD grade, don't use CF.

 

Tim

[Geoff]

Struggling to find reasonably priced 20W-50 API-CC oils, at the moment though, without resorting to the extra costs of mail ordering. Chandleries don't seem to routinely stock a 20W-50, or at least not ones I've been to recently.

 

Try this Alan

 

http://www.diy.com/diy/jsp/bq/nav.jsp?acti...p;isSearch=true

[RLWP]

I've just checked the wording of the Lister H series manual, which seems to have been written when CD was the highest detergency spec readily available!

 

From the horse's mouth, so to speak, for the doubters:-

 

To paraphrase, it specifies a minimum spec of API-CC, and CD for turbocharged engines. It also says CD can be used with advantage in heavily-worked naturally-aspirated engines but to stick to CC for new/newly reconditioned engines and for those which are not heavily worked because using CD can 'inhibit running-in, and give rise to bore glazing in engines operating on low duty cycles'

 

Normal canal pleasure boat operation can certainly be regarded as low duty cycle for most of the engines used.

Note that the reply from Beta said 'provided the right grade of oil was used', so take care to stick to their recommendation, for instance if they say use a CD grade, don't use CF.

 

Tim

Tim, I'm glad you posted that because it corresponds with my understanding of bore glazing. This is a phenomenon that occurs early in the life of the engine when it is being run in. At that stage the rings have not bedded in and allow oil up past the piston and hot gases down into the sump. It is the combination of the hot gas and oil that leads to the glazing of the bore through decomposition of the oil. Once the rings have bedded in, then the bore isn't going to glaze over.

 

The way to avoid bore glazing is to use the right oil and avoid low load running while the engine is being run in. After that, you either have it or you don't and that's it.

 

Richard

[Laurie Booth]

Having read many posts suggesting that running an engine in idle to charge the batteries could cause glazing of the bores, I wrote to Beta asking them if this was an issue. Their response was that provided the correct grade mineral oil was used then glazing of bores would not be an issue. They confirmed that putting the boat into gear to lightly stress the engine whilst moored was not required.

 

Thought I would pass on this information, it might even save some erosion of the canal.

Plus a lot safer, if someone fell in the canal near your boat.

[n.b.Goldie]

Tim, I'm glad you posted that because it corresponds with my understanding of bore glazing. This is a phenomenon that occurs early in the life of the engine when it is being run in. At that stage the rings have not bedded in and allow oil up past the piston and hot gases down into the sump. It is the combination of the hot gas and oil that leads to the glazing of the bore through decomposition of the oil. Once the rings have bedded in, then the bore isn't going to glaze over.

 

The way to avoid bore glazing is to use the right oil and avoid low load running while the engine is being run in. After that, you either have it or you don't and that's it.

 

Richard

If you do have it, and I think I do, is there anything that can be done to correct it without dismantling the engine or thrashing the a***e off it?

 

Ditchdabbler

[magnetman]

I've just checked the wording of the Lister H series manual, which seems to have been written when CD was the highest detergency spec readily available!

 

From the horse's mouth, so to speak, for the doubters:-

 

To paraphrase, it specifies a minimum spec of API-CC, and CD for turbocharged engines. It also says CD can be used with advantage in heavily-worked naturally-aspirated engines but to stick to CC for new/newly reconditioned engines and for those which are not heavily worked because using CD can 'inhibit running-in, and give rise to bore glazing in engines operating on low duty cycles'

 

Normal canal pleasure boat operation can certainly be regarded as low duty cycle for most of the engines used.

Note that the reply from Beta said 'provided the right grade of oil was used', so take care to stick to their recommendation, for instance if they say use a CD grade, don't use CF.

 

Tim

 

Is that H series manual for the air and water cooled units?

 

I believe that bore glazing is more likely to occur in air cooled engines due to the lack of a thermostatically controlled cooling system leading in some cases to overcooling when run on low load.

 

whereas in a modern water cooled engine such as a Beta Kubota, providing that it reaches its correct operating temperature, there will not be a bore glazing problem regardless of load.

Edited January 6, 2010 by magnetman

[RLWP]

If you do have it, and I think I do, is there anything that can be done to correct it without dismantling the engine or thrashing the a***e off it?

 

Ditchdabbler

 

Unfortunately, no. The solution is to have the bores honed to reinstate the surface. That's a head off, pistons out job.

 

Why do you think you have glazed bores?

 

Richard

[alan_fincher]

Try this Alan

 

http://www.diy.com/diy/jsp/bq/nav.jsp?acti...p;isSearch=true

Thanks for that....

 

I have never been successful in finding in in a B&Q yet.

 

Very annoyingly we were in the (very) big B&Q Warehouse in Watford (Herts) only a few days back, but couldn't find a "motoring" section. When we enquired we were told they did not have any motoring products.

 

But now I check the B&Q site, it says that oil is available there.

 

One day I'll get lucky and find an intelligent life form in one of these stores. :lol:

 

(Shan't be venturing there today though - snow still falling steadily).

[n.b.Goldie]

Unfortunately, no. The solution is to have the bores honed to reinstate the surface. That's a head off, pistons out job.

 

Why do you think you have glazed bores?

 

Richard

The crankcase is supposed to have negative pressure (vacuum) whilst running but it in fact has a positive pressure of about i" measured by a manometer. The engine is a Lister LPWS3.

 

Although the exhaust is not smoky is does lose a bit of oil, there is an oil leak from somewhere around the crankcase door. The Lister manual warns that positive crankcase pressure could result in oil leaks. The engine has done just over 3000 hours.

 

Ditchdabbler

[Timleech]

Is that H series manual for the air and water cooled units?

 

Both (HR2, 3 and HRW 2,3), but I think the wording is generic for a range of Lister engine manuals. For instance none of these engines was ever offered in a turbocharged version, to the best of my knowledge.

 

Tim

 

Tim, I'm glad you posted that because it corresponds with my understanding of bore glazing. This is a phenomenon that occurs early in the life of the engine when it is being run in. At that stage the rings have not bedded in and allow oil up past the piston and hot gases down into the sump. It is the combination of the hot gas and oil that leads to the glazing of the bore through decomposition of the oil. Once the rings have bedded in, then the bore isn't going to glaze over.

 

The way to avoid bore glazing is to use the right oil and avoid low load running while the engine is being run in. After that, you either have it or you don't and that's it.

 

Richard

 

I don't think it's quite that simple, I believe it can develop later, but certainly new bores etc will be 'prime time' for developing or avoiding it.

 

Tim

[steelaway]

Thanks for that....

 

I have never been successful in finding in in a B&Q yet.

 

Very annoyingly we were in the (very) big B&Q Warehouse in Watford (Herts) only a few days back, but couldn't find a "motoring" section. When we enquired we were told they did not have any motoring products.

 

But now I check the B&Q site, it says that oil is available there.

 

One day I'll get lucky and find an intelligent life form in one of these stores. :lol:

 

(Shan't be venturing there today though - snow still falling steadily).

 

 

Hi Alan

 

It seems the CC grade stuff is sold in 1ltr for garden machines - its probably stocked in that section, not motoring.

 

Alex

[alan_fincher]

Hi Alan

 

It seems the CC grade stuff is sold in 1ltr for garden machines - its probably stocked in that section, not motoring.

 

Alex

Maybe, but the link Geoff provided is to 4.5 litre containers of the stuff, which would clearly be better.

 

According to the B&Q web-site Watford should have that size somewhere in store.

[BEngo]

If you do have it, and I think I do, is there anything that can be done to correct it without dismantling the engine or thrashing the a***e off it?

 

Ditchdabbler

 

 

Ambesta Glaze Buster by Morriss's of Shrewsbury. Usual disclaimer.

 

N

[Geoff]

Maybe, but the link Geoff provided is to 4.5 litre containers of the stuff, which would clearly be better.

 

According to the B&Q web-site Watford should have that size somewhere in store.

 

I bought some a couple of months ago, yes it is a 4.5l can

I had a good hunt round the motoring section and gave up - seem to remember it was in a most obscure place.

Had to ask for it

 

Geoff

[bag 'o' bones]

All engine bores glaze with time its called engine wear. Doesn't really matter though as by this time the rings will have bedded into the bores and should be ok.

[Timleech]

All engine bores glaze with time its called engine wear. Doesn't really matter though as by this time the rings will have bedded into the bores and should be ok.

 

No, bore glazing is the buildup of a layer of baked chemicals on the cylinder wall, which stops the rings from sealing properly.

Not the same as wear, but the symptoms may be similar.

 

Tim

[RLWP]

Ambesta Glaze Buster by Morriss's of Shrewsbury. Usual disclaimer.

 

N

Have you used this? Ambesta link I've done a quick google and found a couple of boat users who say it works.

 

Richard

[bag 'o' bones]

No, bore glazing is the buildup of a layer of baked chemicals on the cylinder wall, which stops the rings from sealing properly.

Not the same as wear, but the symptoms may be similar.

 

Tim

 

I was thinking more along the lines of the removal of cross hatching as the bore weared.

[Yoda]

The crankcase is supposed to have negative pressure (vacuum) whilst running but it in fact has a positive pressure of about i" measured by a manometer. The engine is a Lister LPWS3.

 

Although the exhaust is not smoky is does lose a bit of oil, there is an oil leak from somewhere around the crankcase door. The Lister manual warns that positive crankcase pressure could result in oil leaks. The engine has done just over 3000 hours.

 

Ditchdabbler

 

A piston engine crankcase should not show positive pressure all of the time. It is better to show no pressure. Any positive pressure will cause blow-by of the piston rings and oil leaks from the crankshaft end seals, positive breathing from vents to dieseling.

 

If you think that you have glazed bores, fit new piston rings.

[Derek R.]

As Tim states, glazed bores are bores which have had a chemical build up through lack of heat which prevents the rings from sealing against them. The symptoms will be excessive smoking and oil consumption. Glazed bores are nothing to do with how old or new an engine is, but how much work it has to do. Diesel engines do not like slow running, light loads at or near tickover - so that bu**ers most of us up. They need to be worked, so that lovely big three or four pot monster is never going to get the work out it needs to keep clear of glazing. Air cooled engines do not have the same temperature controls as water cooled as Andrew states, and can run too cool and glazing will occur. Along with the excessive oil consumption, roof mounted exhaust pipes will give an excellent demonstration of an oil spitter, along with attractive patterns of black dribble from the base joint and across the roof.

I came out of Blisworth on my first trip, plastered in soot from no cutter, and flecked with black oil everywhere - "What do you look like?" - "glazed bores my dearest".

 

Diesels are happiest running at constant RPM well into their torque band, under constant load - ships at Sea; generating sets; pumps.

 

I was advised not to use high grade oils as are currently available in an old engine, their build tolerances were not designed for thin slippery oils. A Petter engineer now retired whom I once contacted, advised me that they used to take an egg cup full of VIM and sprinkle it into the intake with the air cleaner off while the engine ran on tickover. Scoured them out nicely he said. I cannot help but wonder how much of the VIM got into the circulatory system. He didn't think there was a problem - but I would advise against such steps and say - don't do it.

 

Products that claim to decoke an engine from a toothpaste tube are equally suspect. Glazed bores are remedied only by removing the bores and having them parallel honed on the bench. After such treatment it may feel like a very rough surface, but put it together and run it up, give it some work. Just replacing rings alone is a waste of time - the rings will not be the problem unless they are past their service limit (or broken of course), you will achieve nothing but frustration that way.

 

Rather than run a main engine to generate, it might be best to invest in a super quiet diesel genny, permanently mounted in soundproof box and on rubber mounts. We had a PAZ1 on the foredeck of the Dutchman in a metal box, with 'pepper pot' exhaust - what a racket! I lined the box with carpet underlay glued on, and put a Mini absorption silencer in place of the 'pepper pot' - it whispered after that.

 

One of my pet hates: Tied up away from everyone, shut the noisy donkey off and enjoying a brew. Along comes another boat, ties up within a length of me, plonks a petrol genny on the back or the bank, and runs it up for the tele. They don't run too well under water them little portables.

 

It's 'Im.