Crank shaft / Alum smear

[tal320]

Kohler twin 18 hp with bottom pulled off. Broken comnnecting rod left smeared aluminum on crank bearing surface. Trying to remove alum. without removing crank. Im told of an acid that will remove the aluminum and not harm the crank.

Any help is appreciated.

[Restrorob]

Use a long strip of fine Emery paper about a inch wide to remove and buff clean. Then flush the engine block with a cleaning solvent.

[General Landscaping]

I'd keep looking for more info online, but it seems like muratic acid is what you are looking for..... pool supply store or Home Cheapo.

I know emery cloth is the usual way to do it; but it seems like that would remove some material from an already worn rod journal:confused:

[khouse]

the last thing i would do is use any acid on a engine when 2 minutes with some emery paper like Retrorob posted would do the trick. you would spend days on the journal before you would begin to undersize it.

[Jim@MilkyWay]

I'd keep looking for more info online, but it seems like muratic acid is what you are looking for..... pool supply store or Home Cheapo.

I know emery cloth is the usual way to do it; but it seems like that would remove some material from an already worn rod journal:confused:Correct me if I'm bad, but aren't cranks made of hardened steel?
Not only will emery be so "slow" at material removal as to be _totally_ negligible, on the journal, but it will also de-glaze the surface and allow better break in of new bearing.

[Restrorob]

Correct me if I'm bad, but aren't cranks made of hardened steel?



Yes they are Jim, Thats why it's best to use emery cloth to remove the softer aluminum quite quickly and not have to worry about under sizing the journal.

[khouse]

restrorob and jim have it right. no need to reinvent the wheel.

[tal320]

It works. Spun rod left 2-mills of alum smeared on the crank. Muratic acid and a eye dropper is the key Took about an hour to drip alum off with crank in place, however I took the second rod off to find more and so the whole crank had to come out in the end so i could polish the bearing surfaces.

Now i need connecting rods. Everyone says they have to special order. Who keeps parts in stock for a kohler 18hp cv18s twin?

[khouse]

what did you use to polish the journals?

[Restrorob]

Took about an hour to drip alum off with crank in place

Who keeps parts in stock for a kohler 18hp cv18s twin?

Man, 15 maybe 20 tops with Emory paper.....

Check here for parts; http://tulsaenginewarehouse.lookupparts.com/parts.asp

[tomo]

hello, have crank linished at machine shop then measure all journals.

tomo:waving:

[hotrodsnapper]

Just to back up the emory cloth bit, I just did this a couple of days ago under khouse and rob's advice. Works like a champ. I've seen enough people mishandle muratic acid to tell that just because you can by it doesn't mean its something you want to mess with.

Just my $0.02

[Oldtimer]

Good info about clearances inside the Kohler engines.

http://www.yetmans.com/kohler/page22_23/page22_23.html

You need to use a mike when tearing down a Kohler engine.

I think you will end up using a new short block.


Oldtimer