Trying to get engine started

by Ben
(Littlefalls, MN)

Tying to get this engine started. I have checked the compression to the best of my ability and it seems to be fine. I also got a new glow plug medium heat because the old one was bad.
I'm not sure what the needle settings are supposed to be and can't get it to turn over so I can hear it run to even try to set them.
The plug is new and glows bright orange. I'm stuck and don't know what else to try. I would greatly appreciate any advice. I can take more pictures or even a video if that would help anyone out.

Comments for
Trying to get engine started

Click here to add your own comments

Mar 29, 2010

Re: Trying to get engine started
by: Pete

Hi Ben,
As a general rule of thumb and a good starting point, the main needle valve should be opened approx 2 1/2 turns from fully closed - in other words screw the needle right in so it won't turn any more and then unscrew it 2 1/2 turns. That will put the mixture setting in roughly the right ball park to begin with.
The other issue might be that it's gummed up with old fuel residue, if it hasn't been run for a long time. Soak the engine in a tub of gasoline or fresh glow fuel overnight and that will dissolve the residue, freeing up the parts inside.
Which fuel blend are you trying it on?

Mar 29, 2010

Non-running motor
by: winco

What Pete has suggested is sound, but it is also possible that the crankcase is losing compression and therefore not transferring the fuel via the transfer port. The usual place under suspicion is the front seal, just behind the prop driver hub on the front end of the crank-shaft. Also make sure that the back-plate is sealed properly.
A good indication of loss of crankcase compression is if: The engine fires after a prime of fresh fuel squirted into the exhaust manifold (with silencer removed), but won't keep running until another prime is issued.
The fuel should also transfer to the combustion chamber after a few drops are applied directly into the air intake (first removing the power to the plug) after placing a finger over the air intake and turning the engine over one complete revolution.
Another possibility is that there is an air leak in the fuel delivery line, an in-line fuel filter can sometime cause this if the seals aren't 100% efficient.
These are all problems that I've encountered with I.C's, but not an exhaustive list. I hope this is helpful? Regards Winco.

Mar 29, 2010

Starting
by: danny

A bit of advice ..don't turn the needle screw in too hard as it damages seat and yes I would try 2 1/4 to 2 1/2 turns out as a starting point and adjust as nessecery when running.

Mar 30, 2010

Reply
by: ben

I'm using Blue Thunder sport formula 10% mixture. I have cleaned the engine and it's not gummed up. I'm starting to think that it might be a compression issue because it seems it's getting fuel and the glow plug is still bright orange.
I have set the needle to around 2-3 turns also, as this is what I have read on the net. However I haven't done a full air leak check on the engine however I did do one on the fuel line, I am confident there is no air leak their.
Wouldn't the engine at least turn over though even if there is a slight leak if I put a dab of fuel in the carb?

Mar 31, 2010

Age of fuel?
by: Pete

Yes, it should at least fire with a squirt of fuel in to the carb, unless it's flooding each time. After you've primed it have you removed the plug to see if it's wet, or smells of fuel? That will tell you if fuel is getting in to the chamber. If the plug filament is very wet then it's likely that the engine is flooding. Another indicator of this is the prop becomes very difficult to turn over.
Is the fuel new? If it's old then it may have gone off - moisture contamination or evaporation of the methanol will mess things up. You could also try a higher mix of nitromethane, say a 20% blend.

Click here to add your own comments