Holt Engine (I hope)

It started out as 18 KW 3 phase. He took it to a generator shop and they reconfigured it to 14 KW single phase. No idea what they did.
Kubota 28 hp engine running it. Apparently only has about a 100 hours on it.

Greg
 
Again a little more progress.
Machining the valves was worrying me. The stem is a little over 1 1/4 long but only 1/8th dia. Certainly exceeds the stick out diameter ratio. Used HSS with almost no radius, honed on my diamond wheel. Would get about 2 thou taper which I could remove on the spring pass with a precisely calibrated finger pressure on the back side of the stem. lol The sealing face of the valve was cut with a form tool giving the 45 degree angle and a 1/16th radius to the stem. The length of that cut was determined measuring the stick out above the valve guide.
Then needed to drill a hole through the stem for a pin to sit in the keeper. 0.034 dia hole for a 0.033 spring wire. My mill chuck was even close to closing that small. My stash of stuff turned up an old Jacobs 1/4 inch chuck with a Jacobs #1 taper. Made a mandril from 1/2 drill rod. Ended up with 0.002 runout, must be in the chuck. It worked. Made a jig to hold the valve and position the cross hole.
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Managed to snap one bit while testing the jig with 1/8th drill rod. With the bit broke off in the jig I drove the drill rod out, easy to shear a bit that small, then used the shank of the broken bit to drive the remains of the bit from the jig. Project saved. No remaining bits were harmed in drilling the valves.

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Thats as small a drill as I care to use. lol
On a side note, just ordered a 1 1/2 taper shank drill to work on a small backhoe. More my size tooling.

Thanks for looking.

Greg
 
Kept at it today and wound the valve springs, made the keepers and cut the retainers from the same wire as the springs.
Still need to lap the valves, waiting on a set of pin vices.
Sorry for the sh-tty photos, guess my flip phone is for talking, not photography. lol
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Thanks for looking
Greg
 
Im making parts that are fun now. The rad was interesting. The cores started out in life as some 3/4 dia brass rod someone gave me years ago. Through drilled, reduced an end to 1/2 dia to hold in a collet, milled them square, then cut the fins. That got old real quick. lol Plunge move over .1 and plunge, many times, times 7 cores. The tanks came from a 4 x 4 x 3/4 chunk of brass someone. (maybe me) had been using as a cushion, pipe circles on one side and hammer dings on the other. Carving HOLT into the tank with a 1/16th end mill on a full sized mill was interesting, sure no feel, just stare at the DRO. The cores were silver soldered into a header plate, then that soft soldered into the tanks. The first one took a couple of tries, attempted straight soldering it on, lots of leaks, then tinned both halves and sweated them together with a propane torch. Worked like a charm, tested to 20 psi.
The first photo is in normal light, its shiny, the rest are muted to see it.

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Now back to catch up on some real work.
Thanks for looking.

Greg
 
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