Cogsy
Well-Known Member
Flywheel spin test looks good to me too - not much drag in those bearings even with the grease.
Philip Duclos Fire Eater
- Thread starter CFLBob
- Start date
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Thanks for looking and your help. In the big picture, soaking my spare set of bearings really is an easy thing to do. I just think the drag is coming from somewhere else, though.
If the piston and cylinder are dry and clean: it's very good
Flywheel spin test : good
Reassemble the partial, and test it step by step.
Between valves and cylinder surfaces, the valve should not put pressure on the cylinder surface, The valve just slides along the surface of the cylinder, ensuring it is close enough ,you can put little oil between them
Flywheel spin test : good
Reassemble the partial, and test it step by step.
Between valves and cylinder surfaces, the valve should not put pressure on the cylinder surface, The valve just slides along the surface of the cylinder, ensuring it is close enough ,you can put little oil between them
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One more thing, in the video I see the surface of the hole air intake seems not good. If the surface of the hole air intake and slide valve is not straight , it is difficult to seal , and will not create vacuum.
You should place the sandpaper on a flat surface ( glass ) and grind it to the straight (first with sandpaper 100, then sandpaper 600).
You should place the sandpaper on a flat surface ( glass ) and grind it to the straight (first with sandpaper 100, then sandpaper 600).
Thank you.
The valve seems to seal well, but the bent shim stock spring seems to be a weak spot in the design. I keep messing with it, moving it left or right, but nothing has made a difference.
fcheslop
Well-Known Member
Hi Bob, the valve rods needs to be a slide but shake free fit. The wee carrier thingy ma bob the bit that has the cam follower on I thinned it down a bit as Im sure from memory it was causing a bind .It has not caused any probs
The shim bit that holds the valve onto the port face doesnt need to push the valve tightly onto the face it just needs to touch the face as the vacuum will pull it onto the face but if its to hard onto the face the engine cannot exhaust . As Minh Thanh mentions the port face and the valve face need to be flat and its the only area after years of running Iv had to re flattenThe valve needs to be able to swivel on the shim bit thats why it has a rad and the valve has a rad groove cut into it.This allows for any out alignment that may lift the valve from the port face. What thickness material did you use for the valve shim thing as again to thick and the engine wont be able to exhaust
Dont use oil as it wont like it simply scribble over the valve with a pencil .
One step at a time and you will get there as the rest seems good to go,
The shim bit that holds the valve onto the port face doesnt need to push the valve tightly onto the face it just needs to touch the face as the vacuum will pull it onto the face but if its to hard onto the face the engine cannot exhaust . As Minh Thanh mentions the port face and the valve face need to be flat and its the only area after years of running Iv had to re flattenThe valve needs to be able to swivel on the shim bit thats why it has a rad and the valve has a rad groove cut into it.This allows for any out alignment that may lift the valve from the port face. What thickness material did you use for the valve shim thing as again to thick and the engine wont be able to exhaust
Dont use oil as it wont like it simply scribble over the valve with a pencil .
One step at a time and you will get there as the rest seems good to go,
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I used .010" stainless shim stock. Couldn't find .007, without buying a lot of it, so I got a two pieces of .010 from a guy on eBay.
It seems to pull shut and seal just fine. In this post, I show a video where I disconnect the push rod and try to flick the flywheel. The valve pulls shut and won't allow the piston to go far back in the cylinder.
Oil has never touched that area. The only place I've put thin (fishing reel) oil have been the cam roller and that fork you say you thinned out. I was thinking of doing exactly the same thing to that: thin it out, then sand it to more of a polish.
fcheslop
Well-Known Member
Hi Bob, I think at the moment finding /eliminating any sticky points would be the way to go and than have a look at the valve gear.
I cannot remember what my shim thing was made from probably a bit of shim or an old tin can as its gone rusty
Iv had a look at my old banger and the reason I thinned the follower carrier seems to have been a slight out of square on the cams working face as I can see it rotates the carrier very slightly when you turn the engine by hand.
The shim part only needs to very gently hold the valve onto the face just enough to stop it falling of. I know I keep muttering on about this part but if not right it will stop it from running or at least thats my experiance
I need to rework my engine its still a good runner but it could do with a freshen up
cheers
I cannot remember what my shim thing was made from probably a bit of shim or an old tin can as its gone rusty
Iv had a look at my old banger and the reason I thinned the follower carrier seems to have been a slight out of square on the cams working face as I can see it rotates the carrier very slightly when you turn the engine by hand.
The shim part only needs to very gently hold the valve onto the face just enough to stop it falling of. I know I keep muttering on about this part but if not right it will stop it from running or at least thats my experiance
I need to rework my engine its still a good runner but it could do with a freshen up
cheers
Thanks, Frazer,
So far, no joy, but everything moves pretty easily until I put that pushrod in place. I took about .010 off the thickness of that roller fork and then found I got more room by putting the crank a little farther out on the shaft. Now there's plenty of room in that area, but something still just isn't right.
So far, no joy, but everything moves pretty easily until I put that pushrod in place. I took about .010 off the thickness of that roller fork and then found I got more room by putting the crank a little farther out on the shaft. Now there's plenty of room in that area, but something still just isn't right.
Until now, everything I see and hear you say is perfect fit with the way I do flame eater engine
I really only have one
You adjust the valve a little bit forward ( or backwards ) and run it, bit by bit.
You will find a position that seems like it wants to run, continue to adjust the valve .. and position the flame. BUT: make sure everything is smooth, and air tight. It will run
Flame eater is a difficult engine, Just think in your mind: it has very little power, reduce the friction and air tight as much as possible !
as fcheslop has said: "Good luck they are frustrating little beggars to build but great fun when they run"
I really only have one
You adjust the valve a little bit forward ( or backwards ) and run it, bit by bit.
You will find a position that seems like it wants to run, continue to adjust the valve .. and position the flame. BUT: make sure everything is smooth, and air tight. It will run
Flame eater is a difficult engine, Just think in your mind: it has very little power, reduce the friction and air tight as much as possible !
as fcheslop has said: "Good luck they are frustrating little beggars to build but great fun when they run"
In that article on Jan Ridders site that I think you sent me to, he says it might take as many hours getting it to run as it took to make the engine, and I'm not there yet. It took me a lot of time to make the parts. Some of them I had to make more than once.
There's still something not right with the valve push rod. Until I hook that up, it spins pretty well. Once I hook that up, it doesn't. That's what I'll try to figure out today.
fcheslop
Well-Known Member
Does the valve rod slide in the hole thats machined into the cylinders upright?
Is the valve rod parallel to the flat machined on the cylinder
Just wondering is something is out of square and jamming a bit
cheers
frazer
Is the valve rod parallel to the flat machined on the cylinder
Just wondering is something is out of square and jamming a bit
cheers
frazer
I just took it apart in an effort to find that. Nothing definite yet. The hole is marked "Drill or Ream 1/8" on the drawings. Those are different classes of fit. I only have .001 over or under reamers, so it's probably reamed .126. The 1/8" drill rod is tight fit in it. I opened the hole to 9/64, now it's a bit sloppy.
If need be, I can drill it out larger and turn a bushing for it that's 1/8 ID and whatever OD I get away with.
Bob
Cogsy
Well-Known Member
Bear it in mind that when the valve rod is hooked up the valve should be operating and the engine will be resisting being turned over without a flame if it is sealing correctly. Only you will be able to tell if it's mechanically binding or not, of course, but spin tests with it all hooked up should probably be done with the flame lit. You may even get lucky and it will just start up and run for you. When I built my Jan Ridders one, it took many hours over many days to get it to go, even when I was certain it was all correct. The flame position on mine is extremely touchy and if it's a bit off it just won't run.
Thanks, Al.
I've spent a lot of time watching YouTube videos of flame eaters running, and the one thing that stood out was everyone playing with the flame. I also noticed that when people turn the engine on a turntable, the speed will change. Don't know if that's from a fan or something in the room, but they seem really sensitive.
fcheslop
Well-Known Member
Hi Bob, The Duclos engines dont suffer as badly as the Ridders engines about flame position. The flame needs to cover the port so you are not pulling cold air in with the hot. On the Utube vids its probably the flame wandering a little as they turn the engine as they dont like it.
The Duclos engines are the best runners in my humble opinion once set up they usually just run and run without the the faff that the Ridders engines seem to need thats the internal and external valved ones. I think Iv build about 8 of these beggars now and every one of them has had a few problems mostly of my making
Once the binds are sorted when you spin the motor over you should hear a definite and sharp quacking farting noise this is the engine exhausting
Funny youre build has made me look over my old banger and the hole for the valve rod has a bit shake rattle n roll in it now and it could do with bushing
Im a tight wads of Scottish parents so for reamers I tend to make D bits from the Drill rod Im going to be using sometimes they are a little tight but more often good to go .
Just a wee tip from clock it n flog motor engineers
The Duclos engines are the best runners in my humble opinion once set up they usually just run and run without the the faff that the Ridders engines seem to need thats the internal and external valved ones. I think Iv build about 8 of these beggars now and every one of them has had a few problems mostly of my making
Once the binds are sorted when you spin the motor over you should hear a definite and sharp quacking farting noise this is the engine exhausting
Funny youre build has made me look over my old banger and the hole for the valve rod has a bit shake rattle n roll in it now and it could do with bushing
Im a tight wads of Scottish parents so for reamers I tend to make D bits from the Drill rod Im going to be using sometimes they are a little tight but more often good to go .
Just a wee tip from clock it n flog motor engineers
I must be close, because I'm getting that noise, but I got that from the start. It has gone away and come back. I get some binding over half the cycle, when the piston push rod is pulling the piston out, and the crank arm is pointing more or less up.
fcheslop
Well-Known Member
Maybe worth trying to make sure the cylinder is square to the crank or does this not happen with the valve gear removed
You may have enough clearance on the cylinder mount and main bearing mount bolt holes to wiggle it about
If you look on the piston for rub marks it may give you some indication as to whats going on
As in say scuffing top right and bottom left on the piston would point to it been out of square
cheers
You may have enough clearance on the cylinder mount and main bearing mount bolt holes to wiggle it about
If you look on the piston for rub marks it may give you some indication as to whats going on
As in say scuffing top right and bottom left on the piston would point to it been out of square
cheers
Just remind you of how the valve is sliding and air tight, as well as when fully assembled it works smoothly :
