Ceramic Coating 7M Crank

Van

87t Hardtop
Mar 26, 2006
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Oak Grove, OR 97267
I'm planning on a ceramic, dry film, lubricant for the journals, to reduce friction.
What are the advantages in having an oil shedding, ceramic coating put on the rest of the crank? Thanks. Van :1zhelp:
 

gaboonviper85

Supramania Contributor
Jan 13, 2008
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Van;1410923 said:
I'm planning on a ceramic, dry film, lubricant for the journals, to reduce friction.
What are the advantages in having an oil shedding, ceramic coating put on the rest of the crank? Thanks. Van :1zhelp:

Your money would be better spent doing a weight reduction too the crank added with a cranks scraper.....at 6000rpm oil sticking too the crank isn't the problem...it's oil hitting the crank and the cranks mass that hurts...that my opinion.
 

Zumtizzle

Can't Wait to Be King.
Oct 21, 2006
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Dry Film on the journals is nice.

Not really sure about the ceramic coat.

I'd wait for Adjuster to chime in. he's the coating king.
 

jdub

Official SM Expert: Motor Oil, Lubricants & Fil
SM Expert
Feb 10, 2006
10,730
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Dry film on the journals is fine...make sure you double check clearances.

Ceramic on the crank is a waste of $$$. Spend it on a 7M crank weight reduction & knife edge.
 

gofastgeorge

Banned
Jan 24, 2008
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Never seen anyone do either........
Ceramic is normally used as a heat barrier,
and dry film, like what is used on pistons wears quite quickly, and the result would be detrimental to bearing clearances.

I have seen hard chromed bearing journals.
it is much harder than the base material, and will stand up to a spun bearing.
Since it can only be ground with a diamond stone,
if it gets bearing material stuck to it, you can remove it with emery cloth, and never effect the journal diameter.
But it has to be done by someone specializing in cranks because there is a post treatment required to remove hydrogen embrittlement that comes from the plating process.
Not to mention the correct grinding equipment to bring the journals back down to size.

A quick google seach brought up severay places that do it.
Like these people:
http://www.ecgrinding.com/About_us.html
 

Van

87t Hardtop
Mar 26, 2006
974
0
0
Oak Grove, OR 97267
To everyone who already sumbitted a response; thanks for the information.
I need to add that the ceramic coating is reported to act as an oil shedding coat to reduce parisitic drag on the crank. Also I need to correct that the crank is a 6M crank (not 7M), that it has been lightened, but not knife edged, and will see 7500 RPM regularly at the track. The oil pan has both a crank scraper and windage tray and has increased oil capacity by two quarts. All the oil will see cooling above 200 degrees, through a large RX7 thermostatically controlled oil cooler.
I'm aiming to shave off another second on lap times.
I neglected to put that in the original post. Van
 

logan

3 laws safe
Oct 4, 2005
109
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U.S-U.K
You also have the option of DLC (diamond like coatings). I think nascar uses it on their piston pins. No idea what that would cost though......
 

IJ.

Grumpy Old Man
Mar 30, 2005
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I come from a land down under
I'd be looking at one of the teflon coatings if Oil shedding is the aim, I wouldn't be comfortable trusting the Ceramic bond on a crank in case if flakes in use.

Personally can't see a second in any of this.
 

sethron71

Authorized Vendor
Jul 19, 2005
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www.SethIngham.com
Van;1411083 said:
To everyone who already sumbitted a response; thanks for the information.
I need to add that the ceramic coating is reported to act as an oil shedding coat to reduce parisitic drag on the crank. Also I need to correct that the crank is a 6M crank (not 7M), that it has been lightened, but not knife edged, and will see 7500 RPM regularly at the track. The oil pan has both a crank scraper and windage tray and has increased oil capacity by two quarts. All the oil will see cooling above 200 degrees, through a large RX7 thermostatically controlled oil cooler.
I'm aiming to shave off another second on lap times.
I neglected to put that in the original post. Van

Hire me as a driver coach or better yet put me in the car!:evil2: Where you running at?

Seth
 

suprarich

Guest
Nov 9, 2005
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ohio
Van - Salt bath nitride will make the journals slicker and make the crank much more durable. And it does not wear off. Not that the stock crank is weak.
 

Van

87t Hardtop
Mar 26, 2006
974
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0
Oak Grove, OR 97267
Wow! There are certainly many choices out there. Many thanks to everyone who replied.
I now need to do more research, starting with this question; who among us has successfully used one of these treatments on either a 6 or 7M crank, in a road race engine? I'm interested in the results after application and then subsequent teardown and inspection. So far it sounds as if the salt bath nitride is a way to go for a durable hard coating. Albeit, hard chrome may also be quite durable for this application. My plan is to use this engine in both time attack and enduro races. Van
 

gaboonviper85

Supramania Contributor
Jan 13, 2008
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Then your best bet is nitride....it changes the metal itself a few .001"'s deep! Nitride won't flake or chip...it will increase the Rockwell hardness of the metal a great deal and will hold an awesome finish! Coatings are asking for trouble and you won't see a full second from any of this...you will have a nice crank though!
 

adampecush

Regular Supramaniac
May 11, 2006
2,118
3
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Edmonton
For simplicity, go with nitriding. I've seen chrome plating used a lot, however, in a few instances I've seen it flake. Unless the plater is top notch, I'd stick to the simpler surface treatment which has no chance of flaking (and can get pretty damn hard).
 

Enraged

A HG job took HOW long??
Mar 30, 2005
1,844
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Victoria, BC, Canada
maybe I'm confused, but if the block/crank/rod had the nitriding done to bearing surfaces, if you spun a rod/crank bearing, would damage be reduced/eliminated?
 

adampecush

Regular Supramaniac
May 11, 2006
2,118
3
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Edmonton
depends how badly you spin the bearing...

high heat typically accompanies prolonged use in a state of reduced lubrication.