WEED EATER HOP UP

for use in boats

Water cooling a weed eater engine is pretty much a must if you plan to use it in a boat. I ran my boat for awhile with an air cooled engine, but it gets hot very fast and performance really suffers.

I decided to try to water cool my engine myself. I'm cheap and more than anything I love a challenge.  I  started first by removing the cylinder. I then measures the cylinder bore. I fabricated a pretty nifty piece out of aluminum to hold the cylinder while the air cooling fins are being machined off.

 I started with a piece of  inch and half round stock aluminum. I turned the aluminum down to fit in the cylinder bore with only .003 thousands of inch clearance. I then center drilled the end  2 inches deep and taped it for 1/4 inch pipe threads. I then cut 4 slots down the end. 1/4 inch pipe threads are tapered so when I tightened the pipe plug it swells the tool out to press on the cylinder and this hold the cylinder tight on the tool so you can now put it in a lathe and turn the fins off.

Be very careful when you measure where you are going to drill the 8-32 bolt that hold the water ring on. If you look at the picture of the inside of the jug you will see that  I didn't measure quite right and I drill right in to the cylinder OUCH! NOT GOOD.

This is what the machined cylinder jug looks like.

This is the engine with the water cooling ring on and the picture of the water cooling ring.

The water ring is made from the canister of a air compressor water separator/filter.

Here is my new 30cc homelite water cooled. I machined the cylinder on this one just like the above McCulloch engine.

I found a better way to make a cooling ring. This cooling ring is made from a 2 inch copper plumbing cap. You can get them at about any plumbing/hardware store.

Here is a picture of the jig I made to drill the holes in the cylinder and on the water ring. It is machined for a perfect fit over the machined cylinder jug and then the outside of the jig is machined so the cooling ring will fit perfect over the outside of the jig while it still on the cylinder. That way when you drill the holes the will be exactly the same in the jug and the water ring.

vHere is a picture of my homemade tuned pipe. It is made from two t-ball baseball bats cut down and welded together. Cost less than $25 and sounds great and makes big power.

MORE TO COME SOON.