Nikasil vrs chrome vrs steel

[Mr. Demeanor]

What are the new sleeveless 4 stroke motors using for coating?

[Tom Foley]

My 245's new nik. Fell apart in less than 5 hr sent them back in u.s chrome they can't say why I now have 2 blocks redone I don't want to build

This is not good news !

[Chaz]

Now uncle Chaz, don’t be dissing on the Fords

. I know people mismatch sleeves all the time with success. Just wonder if they add a few extrer thousandths to em to make em live? Seems like you’d have to have ya junk right to pull it off, since there’s so many problems dialing them one piece plates in for those steel sleeved motas? I would think steel sleeve em all and set cooling system accordingly would be the way to go?

Ohh no Forby , I just looked in my wallet .. I found two current Ford registrations and only one Chevrolet ..
For a 3 3/8 bore , those 2.4's are pretty loose from the factory . Piston already has .009 or .010 in it , if I remember correctly . So neither you or I would put the hole .001 big on top of that .
I don't know of anyone who is doing a F-1 type cold start , but I have a friend who loves these motors and just hates to see a steel sleeve in one . You can't get anyone to do that hard azz industrial type chrome like they did in the days when America was Great and industry was left alone . He11 there's probably nobody left alive who remembers the recipe . So anyway , LOL , that guy had me get some blank semi ported aluminum sleeves from Advanced . Finish port them to his blocks specs , send them out to get NIC'd then we install them and finish hone them to size .

I know these 280 EFI Offshores and 300 Drag motors were sold as racing engines.
What kind of "Factory Warranty" did they come with ?
Now that they are 20 years old , did some type of "Term Life Policy" take effect ?

I hate messing with the dayum things . At times they seem to be more aggravation than they are worth. Mercury must have planned on the blocks being "throw aways"
They offered no way to easily replace the sleeve . No .001 .002 .003 over pistons where you could quick hone it at a race and keep going . Lot of work and you gotta be on your game . Even with liquid Nitrogen those sleeves will squeak in place or out of place at just the wrong time .. Ooops ahh its only $400.00

There are two company's in the US that will replate . One really doesn't have time and definitely wont do single sleeves ( out of the block mailed to them ) , the other , I have had a good working relationship with . With both 2.5 Merc and Porsche Cyls.

Mr.Demeamie axed a good question . Yes the new 4 strokes use a coated cylinder. Smooth sailin the entire trip .

90% of the 2 strokes plated cylinders trouble begins where the rings work there way back into the bore after expanding out into the port . A little wear turns into a catch , that flakes and *&^%&*&*^# .

The Porsche guys , well I guess it's cuz they can .

[Instigator]

My argument against plated holes (besides PIA and expense) is believing an alum block w/a couple .000" of plating is ever really straight/round.

IMO, if you mic a plated bore at ambient temp then at operating (200* ??) temp, they won't be the same. I don't mean gauge read temps, I mean casting temp under full load at 8k+.
How do you simulate those conditions during casting/matching etc??

I read a really good article yrs ago on plated vs iron sleeves and it was a wash.
Heat t.fer goes to plated.
Straight bores to iron.

Now add in that I can wipe a toasted piston off my iron linered OMC with muratic acid I bought at Home Depot and stick in a new/old piston and go......, I'm sorry, what was the argument ��

[Da Bull]

Interesting point Gator.

[Instigator]

Interesting point Gator.

Bobby when I started playing w/sleeves in my JohnRudes I thought I could swap one and head to the ramp.
Not so.
Mic a sleeve after pressing it in block and allowing it to cool. Or run a hone through one.

First time I saw that, my first thought was what if it was only plated ��

But, what do I know ��

[powerabout]

Heat transfer....
I thought we were trying to light a fire and the heated expanding gases pushed the piston down?

[Instigator]

Heat transfer....
I thought we were trying to light a fire and the heated expanding gases pushed the piston down?

The more/faster we can transfer heat from the cylinders, the straighter they stay and lessens chance of detonation.

[Chaz]

My argument against plated holes (besides PIA and expense) is believing an alum block w/a couple .000" of plating is ever really straight/round.

IMO, if you mic a plated bore at ambient temp then at operating (200* ??) temp, they won't be the same. I don't mean gauge read temps, I mean casting temp under full load at 8k+.
How do you simulate those conditions during casting/matching etc??

I read a really good article yrs ago on plated vs iron sleeves and it was a wash.
Heat t.fer goes to plated.
Straight bores to iron.

Now add in that I can wipe a toasted piston off my iron linered OMC with muratic acid I bought at Home Depot and stick in a new/old piston and go......, I'm sorry, what was the argument 😎

Mornin G ,

Until we can get a little man to go thru the combustion process and come out alive to tell us what he saw , we can only guess . The next best thing is to try and replicate running conditions the best we can . The guys who get the closest to real life , usually do the best . My Porsche guys thought it was a good idea to use factory studs in the torque plate honing fixture . And after 1 - 2 sets of jugs , they never want to see those stones go in their cylinders again . That's how they look at every component on their builds . And it shows at the track .



Heat moves metal , especially aluminum . It's a fact of life we can do nothing about. As far as the Merc blocks , they grow long on the thrust face and suck in on the crank C/L like any other bore , just a little more prevalent . Since they are aluminum , they can be pushed back into shape …
As you can see , the register is pretty thin at the top . The sleeve itself is what keeps the bore round at the top ( for all practable purposes ). The register holds it in place and the few thousandths of plating gives a dissimilar material for the piston and rings to ride within .
Honestly , all outboards with a freestanding cylinder to sway in the breeze and rubber 0-ring for a head gasket is gonna be longevity limited on the power it can produce when you compare it to something with solid decks and Teflon rings . I think the correct term for the dance the parts do and the trail of grey bumps they leave behind is called "fretting" …

[whipper]

I dont know all the ins and outs of Nic since Ive always had steel bore but I {knock on wood} have had very little issues with mine running only 7500-7600 rpm. I know some guys run 8000 with steel ive heard. Going on 13 or 14 years now no problems and many hours have no Idea but way over 500 best guess? A couple of years ago i switched the t stats to washers and tune size based on water temps what ones I run. i found this gives me better control of heat transfer at wot runs for distance. A fella on hear made them from Billet very good job i might add. So all i can say is I would have a hard time going nic knowing ive has good success with steel. What does Caldwell use for sleeves in his new Billet motors? I think the oil and fuel air mix and ACU setup plays a large part in making steel live at rpm. Ive run 33cc heads the whole time i might add. My 2 cents on steel anyway I hate saying anything because its been so long since the motor was done I might jinx it! haha

[powerabout]

omc never had a problem with steel sleeve race engines thinking of the 31 m and F1v8 that ran over 8000, just sayin

[H2OPERF]

Just talked with a friend the other day who makes as much power (well way more) as anyone and said plated isn't worth the problems..Dave

[Instigator]

Just talked with a friend the other day who makes as much power (well way more) as anyone and said plated isn't worth the problems..Dave

Remembering this discussion from long ago, I just remembered the much reduced friction of a piston ring on plating compated iron sleeves.

Seems I saw torque wrench spinning a crank on both.

Chaz, I still choose my red neck ways ��

[Chaz]

Remembering this discussion from long ago, I just remembered the much reduced friction of a piston ring on plating compated iron sleeves.

Seems I saw torque wrench spinning a crank on both.

Chaz, I still choose my red neck ways 😉

Three of my favorite four OMC guys in the whole world , throwin NIC coating's under the bus in a row … BAM

Chaz = in todays world ya better bring a light duty digital fish scale to measure breakaway and rotational drag . Watch some of Dick Maskins seminars on block honing from PRI or SEMA on youtube .

Redneck ways .. you don't think I bought that bore jack do ya …

[nitro_rat]

I can wipe a toasted piston off my iron linered OMC with muratic acid I bought at Home Depot and stick in a new/old piston and go.

That trick works on “steel” bore Mercs too. Yeah, I’m gonna keep calling them “steel,” too!