New Holland Igniter Problem

[Stan]

One other thing that I found on these atmospheric valves is that the sealing on the valve appeared to be less when the pressure was applied by a slowly rising piston compared to dumping air in suddenly from an air tank. That is; no leak with a pressure test but still low compression when trying to start.

 

[rudydubya]

PPM, I'm a novice at engine building, but when I was first trying to get my hit and miss engine started, I was having both fuel and ignition problems. I could tell when I was finally getting fuel by the mist coming out of the exhaust when it didn't fire. Do you get a fuel mist leaking out of the exhaust when you crank it for several seconds with the drill? My ignition problems turned out to be arcing from the high-voltage wire to the head, not applicable in your case, and the fuel problem was an intake valve spring too strong (too large music wire). There was enough leakage around the piston and head so that the flywheel would turn over a few turns when I flipped it, but there wasn't enough suction to open the intake valve with that spring. When I made a weaker spring things started working.

Good luck.

Rudy

 

[bmuss51]

i told you in past posts that i was final finishing a nh motor myself. and when i got the motor to the point ready to fire, i had sort of the same problem as you described. i checked the fuel, ignitor for spark and rechecked the timing. and what i found was that after painting i was not getting the spark into the cyl..i did check the voltage at the switch and that showed a complete circut, but i was not getting the voltage to the contact point when assembled. so i had to clean off alittle more paint around the stud head holes ( i am using a head gasket) and then assembled holding the head and twisting against one of the studs and now she fires and runs just like i had it running before the paint job.
just thought i might be something for you to check !

 

[putputman]

Since my last post I have tried quite a few different trial & error processes trying to eliminate some of the possible problems.

My compression testing has dropped to about 30-32 psi. It has remained pretty consistent for a long time. I feel that it is lower than it probably should be. Most of my engines have run between 45 & 65 psi.

First I connected with an electric motor and v-belt and drove the engine at about 150 rpm for an hour and then at 500 rpm for an hour.

Second thing I tried was to lap the intake valve. I also relieved the contact area by changing the valve angle by 3 degrees less that the seat. Try softer & heavier springs. --- No change.

To check for leakage in the head area, I made a new aluminum cover, 3/8 thick, & a gasket to replace the head with all it's holes and moving parts. Had a hole in the middle to check compression. --- No change.

Next I made a cover & gasket to replace the exhaust valve & casting. --- No change.

Next I put a real light spring in the exhaust valve to make it operate like an intake valve, and put a real heavy spring in the intake valve so it sealed tightly. --- No change.

Next I made a new piston with two O-rings instead of the 3 cast rings.. This should show if it is the piston rings that are the problem. --- No change.

I decided to check the compression ratio for this engine. It is 3.2 - 1. That seems very low to me even for a model. Some of my engines figured at about 4.6 -1 and they run pretty good.
I think I figured it right. Stroke + head gap / head gap.

Rudy, yes I do get a mist out the exhaust at times. I usually close the jets a little until that quits. It seems I have a medium knurl on the adjustment screw. I move it one knurl at a time. That is a very fine adjustment.

My intake valve is working. I can see it move and hear it vibrate when turning the engine over with a drill or by hand.

Bmuss51
This is the first of many engines that I have built that I painted before I tried running it. This has been a difficult engines with less than the best castings & prints. I started building it last fall and have walked away from it several times during the build. In fact I built three complete engines and have a 4th almost done while building this one. This last time it sat for two months without working on it. I finally decided to paint it and since then I have been trying to get it running.

I am considering removing the piston & connecting rod and turning the engine over with a drill to see if the igniter has a consistent spark. I will be able to look right down the cylinder from behind the engine.

Does any one feel it is just my attitude towards this engine that is the problem.

 

[Kermit]

Wetting the spark gap in the plug with fuel spray?

see if it trys to 'go' with some butane or propane from a torch near the intake without fuel?


It's a mystery that has my attention, but you could probably do without the aggrevation. :-\

 

[Maryak]

Does any one feel it is just my attitude towards this engine that is the problem.

With the perseverance you have shown todate - Absolutely NOT.

Best Regards
Bob

 

[Stan]

Arv: To avoid the frustration of trying t get your engine running, come to my place and work on three sitting on the bench that I haven't got to run. None are i/c so it should be a rest for the brain.

Right now, I can only offer two suggestions. Try some soap solution around the intake valve stem to see if the valve is seating when cranking. One of the tests with the old garage spark plug testers was to check for firing when under pressure. Some plugs that fired fine in free air stopped firing when the pressure was increased. The remedy was to file the gap on the underside of the ground electrode.

 

[90LX_Notch]

Arv,

I'll throw some stuff into the mix. Just brainstorming here.

Valve timing events: cylinder pressure has a lot to do with valve timing. ie: High performance cams for cars allow the valves to stay open longer (duration) which allows more air in to be compressed on the compression stroke thus yielding higher PSI. If I understand this right, this engine only has an exhaust lobe and the intake opens based on vacuum. I would at least degree the exhaust lobe as if I were installing a cam in a car. ( piston stop, degree wheel and indicator) and make sure they are happening where they are suppose to are to spec. Also, while doing this I would check the ignition timing as far as the points opening and closing in relationship to piston. I would also check for leaks with compressed air right when the ignition would fire.

Did you try different spring tension for the points?

6 volt ignition system- What would happen with 12 volts to it.

What about putting a vacuum gage on it while cranking it with the drill? May at least yield some type of clue as to what is going on.

Along the lines of Kermit's thinking- I don't know how hard it is to pull the ignitor off, spray some Starting Ether in the cylinder, and put it back on and try to start it. Or, you can always spray it down the carb, but I've found that on power equipment a direct shot into the cylinder works better.



Like I said, I'm just throwing stuff out there. I've never built or worked on this type of engine.

Bob

 

[putputman]

Bob, thanks for your vote of confidence. Sometimes we all need that.

Been following your hit & miss build with interest. I bought that book with the intensions of building that engine, but decided to cut mine out of aluminum bar stock instead of fabricating in steel. Turned out to be one of the better running engines.

Stan, I'll give the soap solution a try. I'll have to block off the fuel intake port with a pipe plug to be sure.

As far as the igniter firing under pressure, I certainly hope that 30 psi isn't too much pressure for it. This is the lowest compression pressure of any of my engines.

What type of engines do you have that are giving you problems. Maybe there is something I/we can help with.

 

[kuhncw]

Arv, you probably know this, but I'll mention it. An analog volt meter across the ignitor terminals is a handy way to see if the ignitor has continuity as you are cranking. If the points are making good contact the voltage drops to zero as the contacts close.

Earlier I'd asked if your governr was latching out. I've found on my hit & miss engines that if the governor latches after one firing, the engine seems to run better as rpm stays in a more narrow band. These simple mixers are best in a narrow rpm range. I've noticed on my engines that if I let the engine keep firing so the rpm is increasing, I get to a point where the engine misfires which I believe is due to the mixture being off at that rpm. At least that is my guess. This doesn't help at this point with your New Holland though.

Kent Smith (K & J Machine Shop) in PA, has a New Holland model on his business card so he may know some of the secrets of getting the New Holland to run. He is a vendor at Cabin Fever and his contact information is on Cabin Fever's vendor list. http://www.cabinfeverexpo.com/vendor.html

What type fuel mixer is on the New Holland? Is it a spray bar type or maybe an air valve type like a Lunkenheimer?

Good luck and I think you have a good attitude toward this engine. I am sure you will get it running.

Regards,

Chuck

 

[Stan]

Arv: All three of the engines have been through the usual remake, redo and swear without any good result. One is a Mizer type Sterling that needs the heat of a 60 watt bulb to make it run instead of the heat from your hand. Another is the test tube with steel wool type Sterling that another board member and myself were sharing notes on. He eventually got his to run but I wasn't pig headed enough. The third is a six cylinder elbow engine that requires fairly precise positioning of parts. After making all the parts twice, I found that my Chinese machinist square, used for layout, was not square. The engine and square are now somewhere in the dark reaches of my shop, hopefully to never see the light of day.

I like Sterling engines and fire eaters and I have gone through the frustrations of getting them to run properly but sometimes I just run out of patience.

 

[putputman]

Stan, I have never built any of those engines or any sterling, but I did purchase the Mizer plans, bearings and graphite from Jerry Howell. I also bought 12" of 6" O.D. acrylic from McMaster Carr. I planned to start after I get the New Holland running. Looks like it may be farther away than I planned.

 

[cobra428]

Hey Putputman,
It took me over a month of "playing" with my hit and miss to get it going. I'm feeling for ya buddy! I never messed with ignitor style ign. but here's a few things I noticed. If the engine is in the least bit flooded forget it... pop and spit (smoke from exhaust) compression drops,but no run. I need to clean the plug continuously because it would get wet, carboned up and fowled trying to start "wet". Take the plug out and unplug it hold the wire near but not touching the frame you should see a good spark. Turning the engine faster you should see a "continuous" spark just about. The best runs I had where on High Oct Gas no oil mix (timing 2~3 BTDC). No oil in your car gas! Just be sure to lube valve guides and other mechanics prior to running. 2 cycle oil doesn't belong in a 4 cycle eng. It will fowl the plugs.

Good Luck
Tony

 

[bmuss51]

i saw in one of your posts that it sounds to me that your ignitor is open and then closes as it is being tripped. but if i found out the point contact should closed all the time except when it is tripped. and the opening of the points is what causes the spark.
i have not built the 1/2 hp yet, but on the 1 1/2 hp a way to check the spark would be to on do the access to either valve and look into the cyl to see that it sparks when the piston is at top dead center.
if the engine gets to much fuel it will not fire either. so i had to make a second needle with a lot longer point to make it easier to adjust. because the print needle was way to touchy and it only had to be opened about 3 clicks on a very fine knurl. and sense i lengthened the point i can now open the needle all the way to a 1/4 turn and 2 clicks of the needle either way makes it run lean or floods the engine and that's with a knurl of about 150 notches on the dia. of the knob.

 

[putputman]

Made a little progress over the last few days. I removed the intake valve so I could see into the cylinder. Turned off the shop lights and turned the engine over with the drill motor. I could see almost a constant blue flame even when I run the drill at 600 rpm. This says that the igniter is firing, but is it hot enough to ignite fuel on a continuous basis. The engine only fires intermittently when I try to run it. Is that ignition or fuel?

To check out the ignition problem I decided to mount a set of points and another cam and run it with a buzz coil like my other engines use. I made an aluminum mount that fits on top of the bearing block. . (I didn't have the cam gear for 4 cycle so I had a waste ignition on every stroke) Took a set of points off an Atkinson Cycle engine that I am building. Set it to fire on top dead center. Hooked up the buzz coil & battery. Turned it over and it took off. I made a very slight fuel mixer adjustment and that was all. The engine ran for over ½ hr and seemed to run smoother as time went on.





This kind of answered a lot of questions I had about this engine.
1) It had enough compression
2) The fuel mixer wasn't that bad. I think a finer needle & seat might be an improvement.
3) The intake and exhaust valve were seated good enough.
4) The intake spring was the correct size & weight.
5) The exhaust timing was fairly close. I might be able to improve on it.
6) I must concentrate my efforts on the igniter from now on.

I still have questions about the igniter that must be answered.
1) Is the coil strong enough.
2) Is a 6 V battery enough or should I go to 12 V.
3) Are my points OK. I used 3/32 dia tungsten from a TIG welder for points.
4) Do I keep the points open until just before I'm ready to ignite or do I keep them closed all
the time except when I am ready to ignite. I have heard comments both ways.

 

[joe d]

Arv

Way to go Thm:

You've GOT to be happy with that... looks good, and sounds great.

Figuring out the ups and downs of your ignitor should be a little less frustrating when you at least know that that is where the problem is.

Cheers, Joe

 

[georgeseal]

On a automotive coil, points are closed and current as flowing. When points break the low voltage field inside the coil collapses induceing a high voltage on the high side causing the spark

You could test your points by having them closed (no voltage applied)
and use ohm meter should be close to 0

 

[Stan]

I would say that a blur flame (spark) should be hot enough to fire the fuel mixture. That leaves the question if it is firing at the right time. Is it possible to use a neon bulb or old style timing light to see if the actual spark occurs at TDC? You can also hold onto the hot igniter lead and turn the engine over slowly and get a very close idea of the firing point but you do get a substantial shock.

Your last post indicates that you are feeding the voltage from the buzz coil to the open igniter points. That is similar to the igniter engines that use a magneto that is generating a constant voltage to the igniter and the timing is determined by when the igniter is tripped mechanically.

I see nothing wrong with making at least one trial with a 12 volt battery to your coil if you are sure the spark occurs at TDC. At east you are down to one problem!!

 

[Maryak]

Arv,

Congratulations, "He who dares wins." :bow: :bow: :bow:

Now all you have to do is ignite the igniter. :

Best Regards
Bob

 

[zeeprogrammer]

Arv,

Very very enjoyable video. Loved the sound too. Got my body moving...oddly...but moving.

Very happy for your progress.