Maintaining cross hatching on cylinder

[TexasTea]

Hi all,

Quick question regarding long term use of conventional vs. synthetic oil...

On some of the more in-depth videos discussing long term use of synthetic they tear an engine down and show that the cross hatching on the cylinder walls is still intact with engines ran on synthetic...

I was wondering if someone kept an OCI of around 5,000 miles on a conventional oil, could it be reasonably assumed that the cross hatching will be maintained with conventional oil as well?

 

[jayg]

It depends and nobody is going to be able to answer this question with any kind of accuracy. The type of metal used in the block, rings,air filters, heat cycles. What KIND of synthetic used? What kind of conventional used? Forced Induction............too many variables.

The variables are endless. I've had cross hatching still visible on most of my engines even at 300k or 50 years old. The lot of them on dino their whole life.

It's a metric that is overused/overrated and doesn't actually reflect whether the condition of the motor is in good shape or if one oil was doing it's job better than another.

 

[Donald]

Use oil as recommended in owners manual as far as type, grade and OCI and forget about cross hatch.

I am thinking cold starts rather than oil type will scrape away the cross hatch.

 

[emmett442]

This really has more to do with design than it does with OCI or oil.

Wiping out the crosshatching is a thing of the past, even on poorly maintained engines. Nowadays, most engines use low tension rings and honing patterns are much more aggressive. This keeps friction down and also keeps much more oil on the cylinder walls than old engines used to.

Of course, there's a trade-off - which leads into the topic of higher oil consumption in newer engines...

 

[dwendt44]

Some engines run with chrome bores or nickle plated cylinders and don't have
cross hatching at all.

 

[cmhj]

ask 20 people and you'll get at least 19 different opinions

 

[nascarnation]

The real question to answer is ... what problem are you trying to prevent?
Do you expect your chassis to outlast the engine?
And is piston/ring/bore wear failure mode causing the engine to need rebuilding?

(I'm also curious...do those videos show similar engines in a similar duty cycle with worn bores?)

 

[BrocLuno]

Tapered cylinder wear was/is a phenomena associated with fuel wash down. Carb'd engines that run rich at idle are the worst. Older engines exhibit more than modern ones.

EFI almost completely cured this. SBF motors out of Broncos and Pick-up with close to 300,000 miles still show cylinder hone patterns. Faint but still visible. Not uncommon at all. And most of those I've seen were run strictly on bulk conventional oil from drums at the ranch.

Has almost no relationship to synthetic. There are no engineering or scientific papers that state that synthetic is better at wear reduction than conventional ...

 

[CR94]

Yeah, I believe that old claim about cross-hatching still visible after X00,000 taxi miles, etc, was in the ads when the original Mobil 1 came out in the 1970s. When ArcoGraphite arrived, too, near the same time.

When I had the head off my Mazda at 476,402 miles, guess what? -- Cross-hatching still visible on every cylinder wall, and more important, no detectable ridge at the top of ring travel. That was on conventional oil of various brands (including ArcoGraphite), mostly 10W-40.

 

[benjy]

recently reading about nikasil plated cylinders + yes they are diamond honed after plating to get the finished bore size + crosshatching

 

[zeng]

Loss of cylinder cross hatch is caused by adhesive wear basically , not so much of abrasion wear and surely not by corrosion wear.
Other things being equal, loss of cross hatch would be dependent on MOFT film thickness whereby conventional oil is never inferior to full synthetics, specifically Grp IV PAO of weaker Pressure Viscosity Coefficient in relatice terms.
No, sources of cold starts wear is corrosion wear in majority,and to a lesser extent abrasion wear followed by adhesive wear where applicable.
JMHO.

 

[SlamFire]

I believe I had Texaco Havoline coolant problems. My 3.9 Liter Dodge engine was made before Texaco Havoline orange coolant came on the market, but based on the bottle claims of compatibility and longevity, I decided to use it. What the stuff did was to eat seals in the cooling system, cause coolant leaks, and that caused a cylinder head to crack. I accidentally found the cylinder head crack after a major coolant leak out of the timing chain cover. One issue with the cylinder head crack was exhaust gases in the coolant system, pressurizing the coolant system, popping even more seals. The intake manifold had popped and unfiltered air got into cylinder #1, lowering the compression to around 80 psia.

These are pictures of the engine around 122,000 miles with the low compression, number one cylinder still showing its cross hatching!. In fact, so did every other cylinder.

This is cylinder number one.





I had no detectable ring ridge. Ran my finger nails across the cylinder bores trying to find a ring ridge and did not find one. GM motors from the 60's, you could crack eggs on the ring ridges when the engines hit 100K.

For most of the engine oil changes I used Walmart Tech 2000 conventional 10w30 oil. Generally I changed oil and filter around 5000 miles. I have found in my records times where I splurged and used Walmart Tech 2000 10w30 Full Synthetic.

After buttoning up the engine with one new cylinder head and a valve job on the other, I drove this engine for 20,000 more miles, with low compression in cylinder one, but my obsessive compulsive behavior kicked in and I replaced the old engine with an advanced auto engine, and I have 40,000 miles on it. It does not burn oil, and I alternate between Walmart conventional 10w30 and Walmart 10w30 Full Synthetic, all depending on how I am feeling.