New welder is on the way thought I would start working on the FL350 cylinder I want to add a water jacket too to improve the cooling of the FL350.

While working on the FL350 Basket Case project http://www.pilotodyssey.com/PO/viewtopic.php?f=5&t=10537 I noticed when heat cycling the rebuilt Engine for the first time that the cylinder above the exhaust port and below the head gets hotter faster and long before the head does, this tells me their is a benefit to adding a water jacket to just the cylinder even when your still running the stock air cooled head, most do this the other way around and add a liquid cooled head never touch the cylinder.

Ordered a new welder so I can start welding aluminum in my shop have wanted one of these for years figured I would use a FL350 cylinder that needs a sleeve to practice on.

Started removing the cooling fins best way I know how caveman style, made up my own tool out of a piece of steel that is about 1/4" think think the material is A400 the steel wont bend its like a spring, super hard stuff we used as wear plate at a sand plant works pretty good.

You were not kidding when you said cave man style were you? LOL

I still want this done to a cylinder I have that is at 85mm bore. Between that and my Hillside Honda head, it should run like a iceberg!

Rand

Have a better way to remove them?

I need to get my bigger lathe running and see if turning them down in the lathe is faster, have it outside using a grinder on it now I have broken out all the easy stuff, has to be a faster/easier way to remove them.

Hoser do you know what a trepanning tool is?For the lathe?

How about plasma and the lathe?Plasma and a wood pattern/guide?

Large core style drill?In the lathe.

Just throwing out what pops in my head,but my first try would be a trepanning tool,at least down to the ports.That stuff cuts like chalk on the lathe.

Found a pic of a trepanning tool.There many,many,variations but this pics shows the concept.

Any pics of a finished cylinder without the jacket?

How far down do you have to remove the fins?

Never heard of a trepanning tool before, looking at your pic it looks like a regular tool holder and a chunk of high speed steel in the tool holder I have both I also have a huge varity of other bits, cutters is not the problem the problem is gearing my lathe down to run slow enough I need to return it to stock gearing the former owner set it up for buffing his bling parts so it runs about 60,000 RPM and sounds like a jet taking off or gear drive on a race car lol then I need to fins a accurate way (fixture) to hold the cylinder by the bottom and the top so I can not only spin it in the lathe to remove parts of the cooling fins but so I can machine the notch in the top of the cylinder to accept the new sleeve, I want to also hold the cylinder by the head end so I can skim cut the bottom of the cylinder to remove caveman damage caused by others and restore the gasket surface.

Far as I am concerned I don't have to remove much more of the fins just need a good flow path for the coolant to go from one side of the cylinder to the other and pick up heat, looking at other cylinders that have been modified this way I already have removed enough, IMO more surface area in the water to transfer heat the better.

The fins don't have to look pretty either they will be inside the coolant loop where they cant be seen I will hit all the surfaces with a grinder to remove all sharp edges, I would hate to create any stress risers that could turn into a crack many years from now then have that crack run across the inside of the cylinder and cause problems.

Someone just did a 350 cylinder here on this site a while back cant remember who shoubadaba maybe? Pretty much doing the same thing.

Your thoughts?

Others thoughts?

Gotta dig out a FL250 cylinder to be done also.

Need to go shopping tomorrow for some aluminum, tungsten, filler rod, some stuff for cleaning aluminum my son was talking about, 50' of #8 wire.

This guy has 20 radiators cheap enough shipping would be the killer, need to contact him see if I can pick up and where is is located exactly.
http://www.ebay.com/itm/20-x-lot-of-YAM ... cf&vxp=mtr

It was a former member Jim327 who did the Ody cylinder modification. He was the other guy who bought a Hillside Honda head like I did.

Rand

that's him thanks he did a great job on his 350 http://www.pilotodyssey.com/PO/viewtopic.php?f=5&t=5853

My bad,skip the trepanning tool,I thought you were removing all the fins from the top down.

In fact,skip everything I said,Ha.

No problem all thoughts/ideas welcome this is my first one, I have seen dozens of them over the years not much to it just need to devise a quicker way to process them I have about three FL350 cylinders to do, one FL350 cylinder repair and a few FL250 cylinders to do.

I think putting in the lathe and attacking from the side would be the fastest, turn them down a much as I can would have to break off the lowest cooling fin because if used the lathe it would be cutting into the reed cage area.

Welder came today

Nice,congrats Hoser.

I was thinking about this some more.

This is what I would do since you want to do multiples.

Use a trepanning tool in the lathe,cut the first four fins off(the ones you did plus the top one)then slip a piece of aluminum tubing down over the whole thing and weld around the top fin/tubing joint and the base of the tube.Size the tube to match the head diameter.

Plenty of sizes of alu tube online.

Would look similar to this....

Thanks for posting Flip I wanted to leave more fins for better, more heat transfer? Wish I had more machining equipment in the shop .

Here are pics of the 350 cylinder that came with TurboTexas "spare Engine" for his Triple E car.

Its past the 82mm bore, the outer shell is really thin like 18 gauge or lighter, appears to be a Kustom Kraft cylinder.

Here is a stock FL250 cylinder that was highly modified back in the old days, also a Kustom Kraft setup only its bored to a 325cc and 350cc if you had the matching stroker crankshaft to go with it.

Water jacket also welded on.

Here is a stock FL250 cylinder that will be modified and get a water jacket like the FL350 cylinder I am doing soon as I get the FL350 cylinder done will start on this one.

i have 3 spare cylinders around here and have thought about doing a water jacket on them and match them to the one that i have now. i would make them so i could just use the same head as i have now on all the cylinders.

That looks like what I was trying to describe.

Start with an aluminum tube instead of flat stock.

I would have to take flat stock and roll it up into a tube or 'pipe' so might as well do like the others, IMO more material left on the cylinder the better its more heat sink, its a place for more heat to migrate too definitely not as sexy as the smaller round setups.

The head on the Engine in the picture is a stock head that has had a water jacket welded on?

Son asked me yesterday when welding on the bottom of that straight fin 350 head why we don't put a water jacket on it, seems like a ton of work to me personally I rather invest in one of them affordable round heads who knows I might make a attempt at modifying the stock head.

Thanks for the pic.

have no clue what this head came off of. kuda had two heads for it but only ever gave me the one, said the other was leaking or something like that..

You don't want to do that.... You want to put a Rotax in there this winter.... I'm hiding away a little each week for if you decide you want to do that deal we talked about.

Finished removing all the cooling fins I am going to remove took it outside and sand blasted the weld affected zone, bought it back in decided I would give the welding a try since my son is out doing his own thing today.

After blasting I noticed why this cylinder had two small holes drilled in it the top fin on one side was cracked they drilled the end of the crack so I welded it up nasty shit in this casting its hard to weld.

Figured I would get in some practice filling these slots that have to be filled since the son was not around to do it, first I cut some pieces to fit then backed it up with a chunk of copper plate.

I have filled many holes in steel using the copper plate backer so on the last hole thought WTH I will try it on aluminum just cover it with all filler no patch piece, works turned out good wish I would have tried this FIRST would have been much faster.

Bottom left weld is the one without the filler piece.



Next I need to cut metal to wrap around and weld up.

Some place I have a few aluminum 1/2" NPT couplings I can use for the fittings to weld on the jacket just have to remember where I put them...