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Jim Laumann
06-26-2012, 10:32 AM
All

I just bought a wood splitter, and have been looking at the placement of the engine (a Honda) on the unit, and the location of the drain plugs. Naturally, the drain plugs are situated so that you can't help but get oil everywhere (on the frame) when changing it.

Were this a Briggs engine, I'd just hit the local hardware store, and get some pipe and fittings - and make a extended drain line. I have done this on some of my other L & G equipement, and has made the oil change process much cleaner.

So I'd like to do this same thing to the Honda - but there is the metric issue. The drain plugs look to be in the range of 1/4" / 6mm +/-, but UI won't know that for certain until the oil needs to be dropped the first time.

I haven't checked the hardware stores yet - so can threading machines cut metric pitch threads? Are metric threaded pipe & fittings available? Can standard black pipe - say 1/4" ID be threaded to a metric size w/o causing the pipe issues - ie weak side walls?

Thanks

Jim

Joe Kieve
06-26-2012, 1:54 PM
Never thought very much about the difference but got me to wondering. I did a quick Google search and found this at McMaster-Carr:
http://www.mcmaster.com/#steel-metric-to-inch-adapters/=i5bkm4. May be of some help to you.

Joe

Still didn't answer your question about hdw. store's being able to metric thread black pipe. Let us know what you find.

Jerry Bruette
06-26-2012, 10:08 PM
Had to do some diggin', but here's what I found in the Machinery's Handbook editions's 21 and 23.

They make no reference to "metric pipe" appears that all pipe is the same diameter but the threads per inch is slightly different on each side of the big pond. Our standard National Pipe Thread(NPT) is as follows.
1/8"-27, 1/4"-18, 3/8-18, and 1/2"-14

Their British Standard Pipe Threads are as follows.
1/8"-28, 1/4"-19, 3/8"-19, and 1/2"-14

The other catch would be they make a tapered and a straight thread. The tapered thread naturally seals with the two mating tapers but the straight thread requires a backing nut which compresses a soft sealing ring against the part with the female threads in it.

So I'm guessing you could take a NPT nipple and thread it into the crankcase of the motor with some type of pipe dope(I'd use some loctite PST) and get it to seal up just fine. Just don't act like a gorilla when you tighten it up. Remember tight is tight and broke is broke.

This is exactly what we do at work for drain pipes on vacuum pumps that are made in Germany.

Jerry

Keith Westfall
06-26-2012, 10:17 PM
Or ask your local Honda dealer....

Jim Laumann
06-27-2012, 12:19 PM
Or ask your local Honda dealer....

Right you are Keith. Doh! Duh! and a couple others....

Joe/Jerry - thank you for the time you spent digging for me.

Jim