Well I was making some progress but now I lost the spark. I rechecked the valve clearance and during the intake stroke on Cyl 2 there was no (negative) clearance on the exhaust valve. I had previously checked valve clearance while only on the compression stroke (all valves closed). I guess my cam isn't perfect. Fixed that and now # 1 AND #2 is getting fuel but no spark on either cylinder. I am recharging the battery and I will try again soon. When this thing finally fires I will have a BIG grin on my face. I haven't lost hope yet. It will run once all the planets align.
damn thing won't run
- Thread starter AllThumbs
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Sorry to harp on about the spark issue.
Plugs sparking out in the open is not the same thing as under compression..
You say your points are insulated from the block - insulated to stand 25kV ??
Since your points and H.T. "ground" end are at the same potential then the spark voltage (which goes up under compression before the spark strike) will try to leak out to the block via your points insulators / cam heel etc.
It's also possible that the H.T. has pinholed its way through one of your insulators - this would not be visible as arcing and might only cause arc suppression under load.
To test for this use a pulse from a coil to a spark gap to the "insulated" points and ground (the block) - it should not spark if the insulation is working - if it does your insulation is insufficient for the voltage and is striking through somewhere. Mount the wire - don't hold it - if it can't find a path to earth it might use you instead.
I presume your whole points system (including the condensor) is insulated from the block.
I very much doubt that a tuffnol heel on the points will resist ignition voltage for long.
I once used a 10" tuffnol rod on an 80kV application and it burned a pinhole right down the rod in about 5 minutes.
Good luck. (The next planetary alignment in 2012 is supposed to presage doomsday according to the Mayan calender - so I don't recomend waiting.)
Ken
Plugs sparking out in the open is not the same thing as under compression..
You say your points are insulated from the block - insulated to stand 25kV ??
Since your points and H.T. "ground" end are at the same potential then the spark voltage (which goes up under compression before the spark strike) will try to leak out to the block via your points insulators / cam heel etc.
It's also possible that the H.T. has pinholed its way through one of your insulators - this would not be visible as arcing and might only cause arc suppression under load.
To test for this use a pulse from a coil to a spark gap to the "insulated" points and ground (the block) - it should not spark if the insulation is working - if it does your insulation is insufficient for the voltage and is striking through somewhere. Mount the wire - don't hold it - if it can't find a path to earth it might use you instead.
I presume your whole points system (including the condensor) is insulated from the block.
I very much doubt that a tuffnol heel on the points will resist ignition voltage for long.
I once used a 10" tuffnol rod on an 80kV application and it burned a pinhole right down the rod in about 5 minutes.
Good luck. (The next planetary alignment in 2012 is supposed to presage doomsday according to the Mayan calender - so I don't recomend waiting.)
Ken
Hope you get it running Eric, I followed the original thread over on CNC Zone also. I might be clutching at staws here but what is the friction like on the engine? Did it spin over freely with head off? Nothing binding?
You'll get there, as with any trouble shooting you just need to do it systematically to get to the cause of the problem.
If there is a spark, fuel and compression there and the friction in the system is low - surely it can only be ignition timing or cam timing. Just another point, you mentioned coleman fuel, have you tried it on petrol?
Nick
You'll get there, as with any trouble shooting you just need to do it systematically to get to the cause of the problem.
If there is a spark, fuel and compression there and the friction in the system is low - surely it can only be ignition timing or cam timing. Just another point, you mentioned coleman fuel, have you tried it on petrol?
Nick
just a thought, have you tried choking it?
turn it over with your finger over the carb for a second, make sure you open the throttle to about half. its possible there just isnt enough fuel in the cylinder.
also it takes more voltage to spark a lean mixture than a rich mixture
turn it over with your finger over the carb for a second, make sure you open the throttle to about half. its possible there just isnt enough fuel in the cylinder.
also it takes more voltage to spark a lean mixture than a rich mixture
You don't need a distributor - the waste fire should work - just use a duplex coil as used on most compact 4 cylinders and most motorcycles for that matter.
This also gets rid of your possible insulation problem on the points.
Not too sure if those duplex coils will work off a points system they are normally run off an electronic unit termed an "igniter" - but I don't see why not.
Ken
This also gets rid of your possible insulation problem on the points.
Not too sure if those duplex coils will work off a points system they are normally run off an electronic unit termed an "igniter" - but I don't see why not.
Ken
I did get a half hour to look at it.
Ken, you made me think. When I insulated the points from the block, I was thinking the voltage there would be just 12 volts between the two. Since I am using the engine block as part of the Hv ignition system, you are correct that the points will see a very high voltage to the engine block. Checking again, I now see that when checking for spark, I would touch the two plugs together and see a nice bright spark at both plugs. I tried again with both plugs against the engine block, I only get a spark at cylinder 1, (plus a brief fire of spilled fuel) the second spark occurring at the points where the insulation is supposed to be isolating things. I think the sort term I will insulate the points better, and the long term will be to find a duplex coil. Hang tight for more results tomorrow.
Thanks for all the help.
Eric
Ken, you made me think. When I insulated the points from the block, I was thinking the voltage there would be just 12 volts between the two. Since I am using the engine block as part of the Hv ignition system, you are correct that the points will see a very high voltage to the engine block. Checking again, I now see that when checking for spark, I would touch the two plugs together and see a nice bright spark at both plugs. I tried again with both plugs against the engine block, I only get a spark at cylinder 1, (plus a brief fire of spilled fuel) the second spark occurring at the points where the insulation is supposed to be isolating things. I think the sort term I will insulate the points better, and the long term will be to find a duplex coil. Hang tight for more results tomorrow.
Thanks for all the help.
Eric
Ok,
As soon as I get the ignition sorted out this thing will run. Did did get a brief run on one cylinder. I took the plug right out of cyl 1 and went with conventional ignition on cyl 2 and it ran for about 5 seconds, the single cylinder doesn't produce enough power to push all the extra hardware around. Now I am looking into a duplex coil. What cars did they come on? Year, make etc? Are they readily available from a wrecker? Also is there any reason I can't go with two coils in parallel for now (one set of points)?
Eric
As soon as I get the ignition sorted out this thing will run. Did did get a brief run on one cylinder. I took the plug right out of cyl 1 and went with conventional ignition on cyl 2 and it ran for about 5 seconds, the single cylinder doesn't produce enough power to push all the extra hardware around. Now I am looking into a duplex coil. What cars did they come on? Year, make etc? Are they readily available from a wrecker? Also is there any reason I can't go with two coils in parallel for now (one set of points)?
Eric
No reason you can't use two coils but it will be harder on the points.
Duplex coils are used on all current (probably last 10 years) compact 4 cylinders like VW & Opel as well a 4 cylinder motorcyles like Honda etc.
They are a lot smaller than a normal coil and I suspect near the limit of capability and because they are bolted to the engine run really HOT- they do pack up from time to time.
These things are normally bolted to the cylinder head cam box.
You should be able to get from a wreckers quite cheaply.
Ken
Duplex coils are used on all current (probably last 10 years) compact 4 cylinders like VW & Opel as well a 4 cylinder motorcyles like Honda etc.
They are a lot smaller than a normal coil and I suspect near the limit of capability and because they are bolted to the engine run really HOT- they do pack up from time to time.
These things are normally bolted to the cylinder head cam box.
You should be able to get from a wreckers quite cheaply.
Ken
It's ALIVE!!! Thanks Chris for the tip, I got a coil from a '99 Buick Regal. The guy at the wrecker gave it to me for free. Thanks everyone for the help!
The one exhaust pipe falls off during the run.
A better video soon.
[ame]http://www.youtube.com/watch?v=rO9nOSBBTR4[/ame]
The one exhaust pipe falls off during the run.
A better video soon.[ame]http://www.youtube.com/watch?v=rO9nOSBBTR4[/ame]
crankshafter
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Hi Eric.
At last you have your engine runing.
Nice engine. Have been following this interesting thread and learned a lot, thank you for the video.
Best regards.
Cranckshafter
At last you have your engine runing.
Nice engine. Have been following this interesting thread and learned a lot, thank you for the video.
Best regards.
Cranckshafter
:big: Congratulations!! It's been a long time coming.
There was a guy over at the Zone asking about an update on the engine. Now you have some good news to report.
What's next? V12?
There was a guy over at the Zone asking about an update on the engine. Now you have some good news to report.
What's next? V12?
Congratulations Eric!! The little critter sounds good.
Regards,
Chuck
Regards,
Chuck
