how common are busted rings due to hitting the wear ridge?

[spasm3]

Originally Posted by Trav
I may also consider a 0w40 A3/B4 in a DI engine. I am interested in bore wear and DI, at what point in the OCI does bore wear spike? Can it be prevented by changing the oil before say fuel dilution increases at a certain point and does dilution cause a loss of lubricity?
I don't know but would be interested in some hard data (not opinions)


I'm waiting till i have a few more miles on it to send off some samples for fuel dilution. I may try the oil analyzers( Amsoil?) as i hear blackstone is not as accurate for fuel dilution.

I want to send a sample 1/2 way through an oci say 2500 miles and another at 5k. Ultimately i'd love to send 2 samples at 2500 miles, one with about 10 miles after a cold start in winter and another fully warmed up at say 20+ miles.

And the same 2 mileage samples at 5k

I don't really want to spend for 4 uoas though.

 

[Trav]

Originally Posted by UncleDave
Never saw a busted ring from a " ring ridge".
UD


And you point is? Because you haven't seen it it doesn't happen?

 

[demarpaint]

I remember rebuilding a Rambler American engine from the 1960's back in 1975 or so. The ridge at the top of the cylinder had to be over 1/16 of an inch thick. The engine was blowing and burning oil at an alarming rate, with well under 100K miles on it. I've also heard that a cylinder ridge might be coming back with the advent of DI engines and increased fuel dilution. I have my doubts it will be as bad as the Rambler engine I rebuilt, but certainly worse than its FI counterpart. It is still too early to tell just how bad a problem this might be.

 

[spasm3]

Originally Posted by UncleDave
Never saw a busted ring from a " ring ridge".



UD



Probably were rare events. It will be interesting to see in the future what happens with DI and Lighter oils.

Remember, ring-lands are now much higher on the piston than the old days. Not a problem unless DI and 20 oils end up causing cylinder ridges to return, if so it could be worse with higher revving engines and high piston ring-lands.

 

[Ducked]

Originally Posted by spasm3
Originally Posted by UncleDave
Never saw a busted ring from a " ring ridge".



UD



Probably were rare events. It will be interesting to see in the future what happens with DI and Lighter oils.

Remember, ring-lands are now much higher on the piston than the old days. Not a problem unless DI and 20 oils end up causing cylinder ridges to return, if so it could be worse with higher revving engines and high piston ring-lands.


Don't get why a high ring-land would make any difference.

The ridge is at ring TDC.

Unless the bit of the piston above the ring has a honing effect (seems unlikely but perhaps not completely impossible) the ridge will be at ring TDC wherever the ring land is on the piston.

 

[spasm3]

Originally Posted by Ducked


Don't get why a high ring-land would make any difference.

The ridge is at ring TDC.

Unless the bit of the piston above the ring has a honing effect (seems unlikely but perhaps not completely impossible) the ridge will be at ring TDC wherever the ring land is on the piston.


Just my thinking here, but the ring is sitting higher on the piston, so its going to be hotter. In my mind hotter means the ring gap might be a bit tighter at TDC than a ring lower on the piston. A slightly tighter ring gap , and now the ridge. could be beakage.
Would not be common, but can anyone say its not possible?

Now on the turbo engines, factor in a cylinder ridge, high piston ringlands, and now some LSPI ?

 

[02SE]

Originally Posted by bdcardinal
With improved machining methods and modern high quality oil this is a non issue. As far as a conrod "stretching" you would only see that in a highly stressed race engine and even that it would be maybe .5mm stretch at the most and maybe if that on a Top Fuel engine where I would default to the resident expert 02SE. When taking engines apart with 150-200,000 miles you don't see a ring ridge and still see cylinder machining cross-hatch.


I have quite the collection of past service limit, or just completely failed TF parts, including Al connecting rods. I consider them art.

It turned out to be a nice weekend in Concord, NC. Fans and teams managed to collect quite a bit of paper products and other necessities for those severely affected by Hurricane Michael.

 

[CR94]

Originally Posted by Snagglefoot
... Fuel injection (resulting in less gasoline contamination) and better motor oils where responsible for mostly getting rid of the issue in my opinion.
I guess that explains why there was no ridge when I had the head off my carbureted '81 Mazda at 476402 miles.

Improved air filtration should get at least as much credit as the two factors you mention.

 

[Ducked]

Originally Posted by CR94
Originally Posted by Snagglefoot
... Fuel injection (resulting in less gasoline contamination) and better motor oils where responsible for mostly getting rid of the issue in my opinion.
I guess that explains why there was no ridge when I had the head off my carbureted '81 Mazda at 476402 miles.

Improved air filtration should get at least as much credit as the two factors you mention.


Has that improved? Not saying it hasn't, just don't remember seeing any data on it.

Tends to be forgotten, though the "most important filter" thing is plausible, seeing as how that's where the silica is.

 

[DoubleWasp]

I saw this in a super old Chrysler 318 marine engine, but that is about it. I have heard of this from some old timers, so it is possible, but on a modern engine? Very unlikely. I haven't seen busted rings from anything except hydrolocking or detonation in a long long time.

 

[Trav]

Originally Posted by Ducked
Originally Posted by spasm3
Originally Posted by UncleDave
Never saw a busted ring from a " ring ridge".



UD



Probably were rare events. It will be interesting to see in the future what happens with DI and Lighter oils.

Remember, ring-lands are now much higher on the piston than the old days. Not a problem unless DI and 20 oils end up causing cylinder ridges to return, if so it could be worse with higher revving engines and high piston ring-lands.


Don't get why a high ring-land would make any difference.

The ridge is at ring TDC.

Unless the bit of the piston above the ring has a honing effect (seems unlikely but perhaps not completely impossible) the ridge will be at ring TDC wherever the ring land is on the piston.


The ridge begins at TDC the point of piston reversal, that point is not necessarily at the top of the bore. The reason one engine and not another develops a ridge is in part due to the material used for the rings, the rings edge profile, the bore finish and probably most importantly improvements in lubrication. I remember well engines being very slow to turn over after a long highway run and attempted to be started 10 min later, the piston rings were tight in the bore and dry.

There was a time when engines were bored (not honed) with the block in the car, there was a boring machine made just for this job, these are long gone along with armature lathes, growlers and most of the valve grinding equipment and brake shoe riveters, I was fortunate enough to have learned how to use them and although not of much benefit today it truly improved my understanding of how these components worked and why they were needed.

In 2 years I will have been doing this work 50 years (I started trade school at 13) so I probably have seen a lot of things young mechanics have never even heard of.
Pre mid 80's and cats oil burning was a serious issue that plagued manufactures for decades, there were two schools of thought, softer rings to minimize bore wear or hard rings to keep a tighter seal longer and allow the bores to wear not the rings.

Article

 

[caprice_2nv]

Carburetors seem to be getting a lot of the blame in here, but I think it has more to do with carburetor problems not being fixed in time. Leaking fuel bowls, out of adjustment chokes causing flooded engines, people that weren't in tune with an engine would badly flood them and the oil wouldn't get changed after that = lots of fuel dilution.

I'm still daily driving my 83 caprice in the winter and last winter I can tell you for a fact that I could smell a ton of fuel on the dipstick in my girlfriend's GDI Sonata and none on the stick of my carbureted Caprice. I wouldn't say my carb is 100% perfectly timed but it starts the first try and idles even in -20 and colder mornings with very little loading up. That's the way they are supposed to work.

 

[supton]

Block hardness? I'm thinking of some of the large gas motors used in trucks. IH 345, 392 and whatever else was out there. Did they avoid ridges? Didn't they also have long piston skirts? not sure how that matters in the scheme of things, not since today engines tend to have short skirts yet are just fine (maybe long skirts helped a problem that no longer exists).

Those engines might have avoided "many" cold starts, not sure what else would have been different in usage. OTOH, unlike passenger car engines they could be counted on to be flogged, and on a frequent basis.

 

[Trav]

Yes carbs get a lot of blame and deservedly so. Back when carbs were the norm more of them were out of whack then those properly tuned for various reasons.
The old Q jets were a balancing act, most had air leaks at the throttle shafts causing it to run lean and leaking bowls on top of that causing it run rich, they needed a bushing kit and better float bowl seal along with some jet tuning to get them anywhere near right.

They all had some real winners too, yes they could all (except the ford VV) be made to run fairly well but the vast majority of them fell into disrepair and stayed that way.

 

[WyrTwister]

I was a senior of class 1970 in High School . Took a vocational class where I went to school in the morning and worked at the local Dodge dealer in the afternoon . I was a go for and flunky in the shop .

At that time period , seeing a ridge ring at the top af the cylinder was fairly common .

As for as broken ring , do not know .

It was common for an engine to be using oil by 100,000 miles .

 

[Chris142]

Originally Posted by supton
Block hardness? I'm thinking of some of the large gas motors used in trucks. IH 345, 392 and whatever else was out there. Did they avoid ridges? Didn't they also have long piston skirts? not sure how that matters in the scheme of things, not since today engines tend to have short skirts yet are just fine (maybe long skirts helped a problem that no longer exists).

Those engines might have avoided "many" cold starts, not sure what else would have been different in usage. OTOH, unlike passenger car engines they could be counted on to be flogged, and on a frequent basis.

Many shops won't bore an ihc engine out. Takes too many bits according to the shops here. Blocks are tough! Back in highschool autoshop our teacher talked about this issue. He said to rev em em up to the moon a few times to stretch the rods.

 

[Ducked]

Originally Posted by Chris142
Back in highschool autoshop our teacher talked about this issue. He said to rev em em up to the moon a few times to stretch the rods.


Did he get heckled, or are US high schools not big on critical thinking?

What makes the "cure" better than the "disease"?

IOW, what stops you breaking the ring during this procedure?

It MIGHT make sense if you very gradually ramped up your stressing, slow enough to gradually hone away the wear ridge by small incremental excursions into the previously unswept area.

Never going to happen, certainly not in "a few times".

 

[Silverado12]

I always thought broken rings were caused mainly by the ridge in addition to other wear like wristpin and bearings. Ether in really cold weather can break rings too. That's why if you must use it try to have the engine turning before you spray it.

 

[caprice_2nv]

Originally Posted by Trav
Yes carbs get a lot of blame and deservedly so. Back when carbs were the norm more of them were out of whack then those properly tuned for various reasons.
The old Q jets were a balancing act, most had air leaks at the throttle shafts causing it to run lean and leaking bowls on top of that causing it run rich, they needed a bushing kit and better float bowl seal along with some jet tuning to get them anywhere near right.

They all had some real winners too, yes they could all (except the ford VV) be made to run fairly well but the vast majority of them fell into disrepair and stayed that way.


I've been driving mainly just cars with qjets for the past 16 years. I've had some problems with them (choke pulloffs, needle and seat plugged up, jets plugged up) but none of them ever wore out the throttle shafts. I've heard it can happen but I definitely wouldn't say "most". They've been pretty reliable for me, but I would occasionally have problems. But these cars also sometimes would sit 6 months of the year while I was driving the other one (summer/winter car - I only insured one at a time up until a few years ago). They would usually start right up and run fine after sitting that long too.

 

[spasm3]

Originally Posted by spasm3
Originally Posted by Trav

As far as bore ridge goes, it is not as common today are it was on older cars because of fuel injection but the reprieve may not be permanent. Studies are showing an increase in bore wear with DI engines due to fuel wetting of the cylinder walls.



Thats what i think also, its one reason i don't run 20wt in my DI mazda. Even with 30wt it may not matter due to the injection pressure. Time will tell. The tech is too new to have a lot of data yet.

Originally Posted by Trav
I may also consider a 0w40 A3/B4 in a DI engine. I am interested in bore wear and DI, at what point in the OCI does bore wear spike? Can it be prevented by changing the oil before say fuel dilution increases at a certain point and does dilution cause a loss of lubricity?
I don't know but would be interested in some hard data (not opinions)


I am thinking about amsoil hdd 5w 30 or the Amsoil signature 0w 40 for summer use in my DI.