Zenoah Glow fuel eng?

[dwilfong]

I have the spacer made and it worked out good to help mate the Tiger King jug to a RCMK case.
The ports in the TK case are HUGE!!!!!!!
The timing came out to 192 ex and 133 transfers.
Do not have to do a thing.
The top of piston to top of liner came in at .110........ perfect....................
Now have to think about the head build up.
How much CR and what style head chamber.
Did some quick number crunching and came up with
11.4 CR
.014 clearance
1cc chamber
0 deg squash angle
.275 squash band width.
MSV 60MPS at 20000RPM
Think I will go Toroidal chamber with brass as the material.
Also no water on the case just in the cap I will build on top of the button.
All that methanol should cool the case off very nice.

 

[Rod Fonda]

Just make sure the ring end gap is large enough so it won't butt together when it gets hot...

Reason I suggested a two ring piston is a single ring is going to be a heavier ring and that can cause ring flutter at the top of the stroke.

Plus a second ring will capture any blowby of the first ring due to flutter...

And lastly, all of the heat in the dome of the piston must transfer to the cylinder walls thru the ring, and having two rings doubles the pathway for heat removal...

All good reasons to run a two ring piston.

It would be cool to see if different types of ring materials and profiles would make a difference in power and longer life/ piston siezure issues..

Just more food for thought...

Not looking to reinvent what already works good.
Keeping it as simple as I can.

Dykes rings would be nice But I don't think thy make one this size?
That would be a easy cut on the piston to try.

This eng layout has the wrist pin front to back not side to side.
The wrist pin is blind on one end to keep the ex from pulsing back to the case.
Have you see any 35mm Dykes rings that are available ?
One more question if you could help me understand the crank end play.
The crank set up as is has no way to clamp one of the inner bearing races to the crank like on a nitro eng.
So do you just let it float?
If so how much end play is needed?

If its more than say .005" endfloat,,you'l have to machine up 1 or 2 shims,or whatever it takes to centre the conrod to piston, depending on how its aligning in the case,,Ive made some very thin shims using stainless bar stock

 

[dwilfong]

If its more than say .005" endfloat,,you'l have to machine up 1 or 2 shims,or whatever it takes to centre the conrod to piston, depending on how its aligning in the case,,Ive made some very thin shims using stainless bar stock

This is set up as a top guide rod.
The rod center is controlled by the piston and the shims on the pin.
There is plenty of side play in the rod bearing and the big end of the rod for play.
Just wondering how much floating crank end play in between the bearings is to little.

 

[dwilfong]

OK the case is all done.
Had to cut reliefs in the case to get the longer bolts in with the spacer.
The adapter plate made for a good transition to the TK jugs large ports.
This is with the spacer on the jug.
With the sleeve installed and the spacer.
It will flow some fuel that is for sure.
Time to assemble the long block.

 

[Rod Fonda]

This is set up as a top guide rod.
The rod center is controlled by the piston and the shims on the pin.
There is plenty of side play in the rod bearing and the big end of the rod for play.
Just wondering how much floating crank end play in between the bearings is to little.

Sounds good,,I'm assuming the crank outer bearings are a slight interference fit in the case and a push fit on the inners ? So under thrust the crank will push on the rear inner bearing ?,as you mentioned it doesn't lock to the front bearing,
I suppose a few thou float or as long as there's no binding and spins freely, should be good

 

[dwilfong]

Ok 1cc Tordial chamber in brass

 

[dwilfong]

How it all stacked up.
Jury is still out on the 12 CR Toroidal head.
Need to get some more input on how much CR will be needed to keep the plug lit in this BIG ringed engine on 15% nitro.
That and how in the hell will I turn it over.......LOL

 

[Daniel's Racing]

The glow plug really tightens up the gas sized engine. There was a lot of space up in those spark plugs.

Have you flat topped the piston also ? If turns out to be too much compression flat topping/small dish may help some or maybe your chamber is bigger than the ones I was using when I was testing methanol and methanol/5% nitro fuel in one I was messing with. 12 : 1 doesn't seem so high. Chamber was opened up on mine quite a bit as well as almost full flat top.

You could barely get mine to start with Model 4 on 24 volt before I started building the gas engine cordless starters.

My God do they rpm up quick and that was with WT499 alcohol carb at only .530"

 

[dwilfong]

The glow plug really tightens up the gas sized engine. There was a lot of space up in those spark plugs.

Have you flat topped the piston also ? If turns out to be too much compression flat topping/small dish may help some or maybe your chamber is bigger than the ones I was using when I was testing methanol and methanol/5% nitro fuel in one I was messing with. 12 : 1 doesn't seem so high. Chamber was opened up on mine quite a bit as well as almost full flat top.

You could barely get mine to start with Model 4 on 24 volt before I started building the gas engine cordless starters.

My God do they rpm up quick and that was with WT499 alcohol carb at only .530"

The piston has a slight dome on it. Much less than the stock piston dose.
I made a custom tool to mirror the dome for the squash band.
Put a 1.12 deg angle on the squash band.
I can make any thing I want as far as chamber design and size.
That is why I when this way with the head and cooling cap.
Also takes all the water off the case.

 

[LohringMiller]

The Zenoahs can have as much as .010". We never worried much about end play with the standard engines. When I get home in a few days, I can measure an engine to check. The crankshaft floats a little in the bearings and it doesn't seem to hurt.

Lohring Miller

 

[dwilfong]

The Zenoahs can have as much as .010". We never worried much about end play with the standard engines. When I get home in a few days, I can measure an engine to check. The crankshaft floats a little in the bearings and it doesn't seem to hurt.

Lohring Miller

It has .020 with the gasket installed.
I had to modify the piston as the top rod bearing set up with the thrust washers did not fit in between the pin bosses.
I checked the rod side to side after it was all assembled and it floats from side to side and dose not touch the crank no matter where the crank is located with the float in it.
So every thing has .020 side clearance, crank and top and bottom of rod bearings.

 

[dwilfong]

May God have mercy on it's soul.....LOL

The carb is .600 x .750 that comes out to the same as a .625 round carb.

 

[Ray Sametz]

 

[dwilfong]

OK ONLY THING LEFT IS THE PIPE
Will try to make a custom header and pipe next.
Have bin playing with some programs based on Blaires stuff. Scott made me a few pipes and some cones. Will pull out the stuff and see what is what. The first 1.01 pipe Scott made was for me and he made a few diffrent ones. Also some cones. TOM may need some help again with the welding.

 

[dwilfong]

Good luck with the glow plug. We did a short series of tests on a Quickdraw with glow ignition and boat fuel. We couldn't get a glow plug to work. The ones that didn't blow out the element wouldn't light the fuel consistently. The engine ran a lot better with ignition on 15% fuel. It fried the points on 40% with piston and exhaust port damage as the electrodes left the cylinder.

Lohring Miller

I held off on a response but.
My buddy got a new QD very recently and has bin fighting with it.
You could run any prop you wanted and as hard as you could in a rigger.
When it cam in you could pick it up by the pipe and it was stone cold.
I will leave it at that.
O an it was with there HOT pipe set up Dyno tuned.

 

[Todd]

Funny he never called me back as many times as we went back and forth on the phone about it. Everything I asked was always NOPE was an answer. That is why we dyno every engine when it leaves here. It either works or it doesn't leave. We have no control over it once it leaves. We even told him to send it back so we could see it. After numerous messages left for him no response back to me. So there is always two sides to every story.

Todd

Quickdraw

 

[LohringMiller]

We set a SAW record with our Quickdraw that stood 14 years as the fastest gas boat ever. The gas sport hydro record, again Quickdraw powered, still stands. Quickdraw was instrumental in picking engines and advising us on those record attempts. Ask Tyler (RaceMechanix) what he thinks of his Nationals winning Quickdraws.

Lohring Miller

 

[RaceMechaniX]

I just need VP to produce U2 again! This boat and motor were dominant 10 years ago.

 

[dwilfong]

OK it is pipe time.
I found a good program to build the pipe from now what to make it out of and how to do it.
So I have weighed all the options and think that a CF pipe build will be the one I can pull off.
Planed on using machinable wax in the lath then wrapping it with CF and epoxy.
So what has bin used in the past to lay up a pipe?
I would need a heat cure epoxy as I need to melt the wax out of the pipe.

 

[dwilfong]

Well have two sticks of 3"x12" machinable wax on the way.
https://www.ebay.com/itm/182844535786I will just make the center out of wax and put aluminum tubes at both ends for the header and stinger sections.
Then wrap it with some CF
I see some talk about the Cortonics 4460 resin.
I will give them a call and see what is what and may be get some coming to try.