Piston ring material & HM oil

[OilUzer]

Very basic question:

Aren't piston rings or seals made of iron or steel or other hard materials in newer cars?
I've read about polymeric (rubber?) seals, but my search comes back only with iron (cast?) or steel rings ...

if true, curious how high millage oil or any other oil for that matter can swell the iron/steel rings? ie swelling or conditioning will cause more/better contact with cylinder walls ...

 

[KevD47]

HM oil does nothing to the rings. It's for gaskets and seals to keep them supple and not leaking as the engine ages.

 

[LeakySeals]

Maybe you're thinking about valve seals?

 

[OilUzer]

How can conditioning or swelling valve seals in older cars have any impact on oil consumption? I can see it improving performance but can't picture fixing oil leaks or reducing oil consumption!

 

[4WD]

The old small block Mopar engines were known for valve stem seals letting oil into the cylinder
(My PowerWagon smoked at start up only)

 

[HangFire]

Originally Posted by OilUzer
How can conditioning or swelling valve seals in older cars have any impact on oil consumption? I can see it improving performance but can't picture fixing oil leaks or reducing oil consumption!

Oil coming through worn valve seals is a common, and often major source of oil burning in older engines. The suction of the intake stroke draws the oil in.

 

[Trav]

Originally Posted by OilUzer
Very basic question:

Aren't piston rings or seals made of iron or steel or other hard materials in newer cars?
I've read about polymeric (rubber?) seals, but my search comes back only with iron (cast?) or steel rings ...

if true, curious how high millage oil or any other oil for that matter can swell the iron/steel rings? ie swelling or conditioning will cause more/better contact with cylinder walls ...



Its claimed that HM has more detergents or esters and can clean the area of the rings on the piston better, if the rings were sticky and it freed them then yes it could reduce oil consumption and raise compression, how long this may take is another question. Sound great on paper, real world experience may differ.

 

[kschachn]

Plus total "consumption" includes leaks.

 

[SteveSRT8]

Yes, HM oil could free sticking rings, but it is hit or miss. The swelling of gaskets, seals, and yes, even o-rings is its best effect, combined with a lot of cleaning.

 

[LeakySeals]

Originally Posted by OilUzer
How can conditioning or swelling valve seals in older cars have any impact on oil consumption? I can see it improving performance but can't picture fixing oil leaks or reducing oil consumption!

Swelling rubber valve seals with HM oil definitely makes a difference with oil consumption. If thats your problem. Less penetration into the combustion chamber at high revs. Less dripping overnight (blue smoke startup) . Valve seal leaks and clogged piston oil return holes end up jamming the rings with combusted oil leading to even more oil consumption. Poor maintenance practices are the primary cause. Chronically late oil changes. Chronically low on oil. Cheap oil.

 

[benjy]

my aunts great runnin leaky 99 jeep cherokee is leaking less with HM oil. HM oils are generally on the thicker end of the centistoke range for their listed viscosity. GM's older cheap O rings on the valves wore quickly + contributed to oil consumption as noted

 

[OilUzer]

Originally Posted by LeakySeals

Swelling rubber valve seals with HM oil definitely makes a difference with oil consumption. If thats your problem. Less penetration into the combustion chamber at high revs. Less dripping overnight (blue smoke startup) . Valve seal leaks and clogged piston oil return holes end up jamming the rings with combusted oil leading to even more oil consumption. Poor maintenance practices are the primary cause. Chronically late oil changes. Chronically low on oil. Cheap oil.


Can valve seals be designed like piston rings? Instead of polymer (rubber) use cast iron, steel, etc.?

 

[SubieRubyRoo]

Originally Posted by benjy
HM oils are generally on the thicker end of the centistoke range for their listed viscosity.


Pennzoil's HMs aren't. I haven't bothered to look at others.