Milwaukee Midget

[jacksoni]

Hope everything goes smoothly Mark.

[Milwaukee Midget]

Hope everything goes smoothly Mark.

As do I.  Mrs. Fordboy is gem, and quite honestly, Mark and I are both blessed with outstanding partners of the first division.

To a speedy recovery. 

[Milwaukee Midget]

         


Fortunately, it appears that the corrosion is confined to the interface between the barrel and the block at the bottom of the water jacket.    And it was easily "broken" with a bit of localized heat from a propane torch and a BFH.   More extensive corrosion might have needed an acetylene torch with a rosebud, but, again,


Some corrosion removal is in order here.   Perhaps bead, or other media, blasting, of the localized, corroded areas of both the block and the barrels.

Looks like the first order of business will be buying some lacquer thinner.

Is bead blast going to be soft enough for an aluminum crankcase where we need to reinsert a close tolerance steel cylinder?

And this one goes out to the machinists among you -

Is it possible to hone these cylinder liners outside of the block to a standard that will get us a proper crosshatch that will work with gapless rings?  We used a deck plate on the A series in order to provide an assembled condition clamp load and minimize bore distortion, but I'm wondering if that's a viable option with a wet liner block such as this?  

[fordboy628]

Is bead blast going to be soft enough for an aluminum crankcase where we need to reinsert a close tolerance steel cylinder?

And this one goes out to the machinists among you -

Is it possible to hone these cylinder liners outside of the block to a standard that will get us a proper crosshatch that will work with gapless rings?  We used a deck plate on the A series in order to provide an assembled condition clamp load and minimize bore distortion, but I'm wondering if that's a viable option with a wet liner block such as this?

Bead blast is probably OK, as long as the blast air pressure is low and the beads are new.    But it does need to be done carefully.

WE, (speaking Royally here) are going to make it "close tolerance", closer than the factory, by individually machining the tops of the barrels to the positive dimension we want to use, AFTER decking the block to the height we calculate.   See, piece of cake, just like Marie Antoinette said . . . . . .     

Let's face it, outside of the block honing of the barrels, is how the factory does it, and it works.   I'm not certain we can duplicate the bore distortion in service, (we never could with the Renault . . . .), we just might have to resort to the "Top Fuel method" . . . . . .  lots of piston to wall clearance to prevent seizing from bore distortion, as I did with the Renault.  As long as we can get it to seal up, I don't care about how much oil it uses, as long as it does not compromise bhp . . . . . . . . . . . . . . . . .   

The only other choice is to epoxy the barrels into the block under compression similar to the "in service" compression, and then hone with a deck plate, etc.    That might make the block and barrel assembly a non-serviceable, throw away item, like a motorcycle block.    I am reluctant to suggest this with out a bunch of spares . . . . . . . .   

The only way to intelligently decide this is to choose the ancillaries for the "package" ahead of time, with these options in mind.    Need to consult with Wossner, Total Seal, Head gasket mfg, etc, to see what they suggest their parts can accommodate.    Kind of like, you know, . . . . . a plan . . . . . . .   

BTW, thanks for the well wishes.

 
Waitingforthedoctorsboy

[jacksoni]

I have heard it said that bead blasting such parts is a no-no because you can't get all the little beggars out of every nook and cranny and therefore they end up in your running engine- a bigger no-no. Plastic or walnut shells maybe?

[RichFox]

we sure bead blasted lots of turbine engine parts when I was doing such things. I never bead blasted my block, but I did compressor housings and wheels when I was running turbos. Pistons also.

[Milwaukee Midget]

Let me try the thinner and some Scotchbrite pads, first.  That's a job I can accomplish while drinking beer, if I'm careful.

[jacksoni]

Also, ring seal (I hesitate considering who is helping out on this deal (Mr FB)) is heavily dependent on a round and straight bore (as well as the hone surface of course). How can you get those parameters optimized when honing outside the block and then installing the sleeves with a BFH?

Though Total Seal says better seal and more power ( I use them but have no idea if their claim is accurate) with gapless rings, many engine builders say they are useless (or at least unnecessary). Just cost more. YMMV

[Rex Schimmer]

Removing sleeves: Why not do it the way the top fuel guys do, a machined slug, similar to the one you have, machined to fit the bore and the step just an RCH smaller than the sleeve OD and a BIG slide hammer.

I would not think that honing the sleeves and then inserting them in the block would have much of a chance to be nearly as accurate as honing the sleeves once installed in the block. Any interference between the sleeve and the block will cause some distortion of the sleeve. I agree with Jacksoni, walnut shells or plastic beads only for blasting the block.

Rex

[jacksoni]

Let me try the thinner and some Scotchbrite pads, first.  That's a job I can accomplish while drinking beer, if I'm careful.

"if I'm careful"  Just don't mix them up......

[Milwaukee Midget]

Jack, we saw a nominal increase in leakdown efficiency when we went from standard rings to gapless.  Numbers are posted here,

2013 -

#1     4%
#2     6%
#3     4%
#4     3.5%

2014 -

#1    1%
#2    1%
#3    3% (likely valve lap)    
#4    1%

According to the Rover manual, the sleeves are a tight slip fit, so I don't think the big hammer will be required.  The design is intended to hold them in place with the long bolts - yeah, I know . . .

When I was working as a lathe operator - I won't take the title "machinist" - I was given the task of whipping out some brass O-ring inserts for Sherwood LP regulators.  I was busting rate on them - or so I thought.  But I had the air chuck overtensioned and it was partially collapsing the ring, so when I checked the ID for roundness, which was perfect when I checked it in the chuck, it quickly went away when I removed 'em from the Warner Swasey.

That was 30 years ago.  It's a lesson well learned, and it haunts me as we move forward on this part of the project.

I would not think that honing the sleeves and then inserting them in the block would have much of a chance to be nearly as accurate as honing the sleeves once installed in the block. Any interference between the sleeve and the block will cause some distortion of the sleeve. I agree with Jacksoni, walnut shells or plastic beads only for blasting the block.

Rex

 

Rex, normally, I'd say you're spot on with that assessment, but the bottom part of the liner that inserts into the crankcase is only about 1 1/4 inch in height, and we're shortening the stroke, so the area of the cylinder liner that is dimensionally critical - where the rings and pistons will be doing their work - are, I think, far enough away from where the liner is set into the crankcase that I suspect it might not be an issue.  But then the issue of a nominally supported liner raises its ugly head.

This one's going to get stupider before I get smarter . . . 

  

[Crackerman]

Instead of blasting, another way to,remove corrosion, stainless wire brush, scrubbing,pad and a use,of a solvent or acid of sort, acetone breaks down passivation layer, vinegar or something stronger, but not muriatic acid, will break that corrosion down even further. You can prevent it in the future by using a glue/epoxy/sealer between liner (or add another anode, such as aluminum based antiseize.
The aluminum and steel are in contact with each other and in a common electrolyte (moisture in oil wicking action uphill) you have to,remove the electolyte to prevent corrosion.

[RichFox]

The liners for my Lotus 907 (Jensen-Healy) were honed .005 over out of the block. I am not scientific as some, but it did seem to work.

[fordboy628]

midget,

GOT to be able to make some dummy test valves out of this lot.   Scored these Subaru cast offs for FREE!
Subarus also use a nominal 6mm valve stem diameter.



Too bad they don't fit up as well as in the original application . . . . . . . .



MAYBE . . . . . it is "worth it" to have Cosworth design your cylinder heads . . . . . . . . . . .

Just sayin' . . . . . . . .

 
Fordboy

[WOODY@DDLLC]

Dry Ice blasting! 
http://mwdryice.com/
http://www.precision-iceblast.com/