starting a jerry howell powerhouse

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jonesie

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looking for help or advise on getting a powerhouse ic engine started. i have run out of things to try and ideas. it has a hall ignition and i get good spark, timing seems to be right , and the ignition fires at top dead center. i also put on a real light spring on the intake, and exhaust vale is opening at bottom of stroke,i tried using what jerry howell used 30/70 ach to coleman fuel.and also straight coleman, but it will still not fire. i turn it over with a cordless drill and you can hear the exhaust. i do not know what the air and fuel settings need to be on the throttle body i have tried opening the air wide open and needle valve closed and then start turning it over and then open needle valve a small amount but it still will not fire. the plans call out for a .025 hole in the fuel spray bar and i opened it up to .028. i also tried spraying starting fluid into the air intake and still nothing.with sparkplug out and touching the cylinder and turning it over i get a nice blue spark.any ideas or suggestions would be greatly . once i get it running i will post a video. thanks jonesie started on a jerry howell farm boy so i hope to get this one running so i can paint or powder coat frame.
 
Hi Jonesie, Perhaps the valves are not sealing properly? Have they been adequately lapped and are you certain that they are in fact sealing as they should? I'm not familiar with that engine but I have seen them, they are a very handsome engine.

BC1
Jim
 
i lapped them in when i put it together and they looked good i have the head off now so i am going to check then, with head off and holding hand over the cylinder it feels like the rings are seated good, when it is being turned over with the drill you can feel the exhaust coming out
 
Jonesie, you should be able to see the intake valve opening when turning it over with a drill. Here's a video of my Henry Ford engine running and you can easily see the intake valve (right in front of the spark plug) opening on the intake stroke.

[ame=http://www.youtube.com/watch?v=y_PFz3hfuKI]http://www.youtube.com/watch?v=y_PFz3hfuKI[/ame]

I would try weakening the intake valve spring, maybe cut off a turn at a time until you can see it opening.

The other thing you might try is making a simple vapor fuel tank and removing the carburetor. That way you can see if it's sucking fuel by the bubbles in the tank when it turns over. Here is a picture of the one I made. Go about half way down page 2.

http://www.homemodelenginemachinist.com/index.php?topic=7931.15

Chuck
 
I have not built one but many things are standard over all internal compustion engines. Just some thoughts.

- Does it "fire" at all?
- Is it a good strong spark? (It sounds like you already have this covered)
- After spinning with a drill is the spark plug wet? If it is wet either you are flooding (too much fuel), or you are not getting spark under compression, or the spark is arching somewhere and not igniting the mixture.
- If the spark plug is dry get a can of gumout carb cleaner. Put a decent squirt in the spark hole or in the intake (get some in by the piston). Let it set a couple seconds to let it create a vapor. Spin the engine with the drill. If it "fires" a couple times that means you have a fuel delivery issue.

You can remove the fuel source and try the gumout trick. If it fires and will run a little you'll know you have a fuel delivery/carburetor issue.

If you have spark, compression, fuel, air, and decently timed (valves closed on compression) you should at least get a puff or two.

Hope that helps a little ;)


 
thanks guys for the tips i am going to try the carb. cleaner for fuel. going to relap the valves, also thanks cfellows i will take a little off intake spring and i have your plans for the vapor fuel tank and i am going to make one i will keep you informed and thanks again for the tips jonesie
 
cfellows said:
I would try weakening the intake valve spring, maybe cut off a turn at a time until you can see it opening.
Chuck

Chuck

Forgive me for daring to be seen correcting you, but if you remove coils from a spring I don't believe it will weaken the spring. If I'm wrong, then I will have learned something new!

Dave
The Emerald Isle
 
I think what is meant is remove a coil to lessen the pre-load on the spring.
 
on my jerry howell ic engine he did not say which way the flywheel is suppose to turn but i think that it is suppose to turn clockwise looking at flywheel or towards the cylinder am i correct in assuming this, still not running relapped valves and used permatex 2 on cylinder head but now i think my timing is off spring on intake is a light spring but still do not see intake valve moving, going to retime and keep tying getting frustrated with it. thanks jonesie
 
Hey, will it bounce on compression? On my engines I've found if they won't bounce they won't run, not very well anyway. All those who mentioned compression know how important that is.
 
what do you mean by bounce on compression, with the head off and my hand over the cylinder and rotating the flywheel i can feel it pulling on my hand. also when turning it over with the drill i can here air coming out off the exhaust. thanks jonesie
 
Bounce; with it all assembled give the flywheel a sharp flip, not so much as to get it over the top but to just bounce off compression. It ought to bounce back. A really good ic engine will rock back and forth a time or two. If it won't bounce back, just kinda dies off, its leaking compression somewhere and probably will run poorly at best. I'm not doing a very good job of discribing it, am I. Another test is you outta be able to roll it up close to top dead center and when you release it it outta fly back some. Early on I made lots of cylinders and pistions that weren't up to par and I did a poor job on a lot of valves and seats too. I was lucky if they ran at all. I'm getting a lot better these days at knowing what's going to work.
 
Valve seating is tougher for me. I generally mount the head to a plate. The gasket doesn't have to be too fancy. I then make an adaptor so I can add a hose in which to blow air into a spark plug hole. I use model airplane silicone fuel tube for the air tube. Submerge the head in water. I then blow into the hose and look for bubbles. If I see a bubble more often then 3 seconds or so I know my valve work is not good enough. Thats the only way I've been able to get my valves seated. I redo valve seating more than any other work.
 
thanks jim i understand the bounce now i will give it a try,also going to check my 6 volt battery to make sure it is good, but i see a nice blue spark on the plug. i will keep this subject posted when i get it going thanks jonesie
 
thanks for all the help and advise,got it back together put in some starting fluid and it started and ran, now i need to get chucks vapor fuel tank hooked up. got the tank build but tired it with the original throttle body but did not run to long on it. i also need to tighten up the timing lever as i got some oil on it and now it is loose, but at least i know it will run so when i get it going good i will try to post a video. thanks again jonesie
 
Thank you for leaving this posted. I built a JH Powerhouse last winter but could not get it started. Spring came and everything was set aside. This fall I started doing some research and found this thread. After checking and following several of the pieces of advise in this thread I was able to get my first IC engine up and running. Thank you. Jim B
 

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