Generator won't start - any suggestions?

[chris64]

This is my last attempt before taking the generator in for professional help. The generator is a Coleman Powermate 5700 watt, it was used for two weeks during a hurricane two years ago. I periodically pull is out, put fuel in it, run the generator till the fuel runs dry and cut off the gas line afterwards. This time, it wont start. The carb is clean, getting plenty of gas to the carb, put fresh gas in generator, changed oil and topped it off to the edge of the opening, new spark plug. I am getting a spark at the spark plug. With the air filter off, spaying carb cleaner/ starter fluid directly into the carburetor, the generator will still not start. Which is wierd because I would think that if I were getting a spark at the spark plug after spraying starting fluid directly into the carb it should start up at least for a second or two. This makes me think it is an electrical issue. I have scoured the web and the only trick I have up my sleeve is to bypass the low-oil sensor and try it.

I guess the question I have if anyone knows anything about generators is if the low oil sensor is bad, would I still be getting a spark at the spark plug? It is unclear to me how to bypass the sensor, but I would think that if the low oil sensor is bad (or the on/off switch is bad on the same note), that I wouldn't even get a spark at the plug. From the bundle of wires coming out of the low oil sensor, it looks like two wires go to the on/off switch, ground wire, two wires go to the low oil light, one wire comes from what looks like a probe inserted next to where the oil is poured in, and the last single wire runs into the engine - I would take a shot and say that goes to the spark plug because it is running in that direction. The other thing that I thought was a big counter intuitive is that I tested the continuity of the on/off switch. With switch "On" I got an open circuit, when it was off, I got a closed circuit (resistance=0). I thought this was weird so I just humored myself and tried to start it with the on/off switch off and still no luck.

I have made up my mind that I am taking it in on Friday, but I thought as a last ditch effort I would post this to my favorite website and see if anyone may have another twist on this problem.
Thanks in advance for any advice.
- I should have bought a honda. Oh well.

[cabinetman]

There's a few simple things to check.

Use fresh gas, and flush carb.

See if the gas line is turned "on", and gas is actually getting to the carb.

Remove the bowl to the carb, to check for sludge. See if the needle is free of the seat and the float is operative.

See if the choke (if any) is operative.

Set the "on/off" switch to "on".

Set the choke to on and do several pulls. Engine may flood, and if it does you may smell gas. If you have spark, at this point with continued pulls, you should get it to fire...even a few times. Wait a few minutes and pull again.

It's possible that there may be an electrical problem. All you need to run is spark-fuel-air.

I bought a new edger that has right on the carb a choke button to depress to choke. It says 3x. Doing that you can pull it all day long and it won't start. It takes a minimum of 7x to fire. Go figure.
.

[RAV2]

Both the on/off switch and the oil level sensor work the same - they ground the electric power to the spark plug (switch off and you ground out the plug's wires :: get low oil and the system grounds the electricity to the plug as well).

Some times when a generator sits, corrosion and rust along the surface of the flywheel causes the spark generated to be less than needed. You see the spark but it is insufficient to fully fire the fuel. Cleaning the rust off the area of the flywheel can help eliminate this problem (also check the coil as well). Did you properly gap the plug and use the correct replacement?

You can (carefully) try some starting fluid - it has a higher flash point - and see if this kicks it over.

[capncarl]

You may be overlooking the real mechanical problem. A valve may be stuck open from setting so long. Do a compression check, if this is the problem the compression will be 0 or near 0. You can do a quick check without a compression gauge by holding your thimb over a sparkplug hole and turning the engine over. Proper compression should blow your finger away from the hole. If a valve is not completely seated you will not have enough compression to fire no matter how much fuel or spark you have. I have experienced this problem with numerous flat head engines on boat generators. Most were solved by discharging the contents of a can of engine fogging oil into the carb and spark plug hole while slowly turning the engine over. Some required simply pulling the cylinder head off and helping the valve close with a few taps from a wooden hammer handle. Turn the engine over and observe the valve operation to make sure that it does not stick open again. That usually fixes this problem. When you shut the engine down for storage you should always use engine fogging oil to help prevent valves sticking and cylinder walls rusting.

capncarl

[parnelli]

The generator is a Coleman Powermate 5700 watt

*runs to garage*.... yep that what mine is

I periodically pull is out, put fuel in it, run the generator till the fuel runs dry and cut off the gas line afterwards.

yes, yes yes, and yes.

This time, it wont start. The carb is clean, getting plenty of gas to the carb, put fresh gas in generator, changed oil and topped it off to the edge of the opening, new spark plug. I am getting a spark at the spark plug. With the air filter off, spaying carb cleaner/ starter fluid directly into the carburetor, the generator will still not start..... This makes me think it is an electrical issue. I have scoured the web and the only trick I have up my sleeve is to bypass the low-oil sensor and try it.

Seriously. Are you in my garage? Is this some sort of alternate parallel universe?

For about a year and a half, the darn thing is sitting buried in the corner of the garage because I could not for the life of me figure out what the problem was. I too was lead down the oil sensor problem path, but never went anywhere with it.

Unfortunately I don't have an answer for you as to what the problem is- but if there's something that I can check/ compare on mine for you just let me know....

[Stytooner]

Not sure if it will help, but here is a link to check out.
http://portablesgenerators.com/colem...700-watts.html

[chris64]

So far to all - thanks for the reply.
I have done all of what Cabinetman recommended - I was under the same inmpression as you. Fresh gas, carb is clean as a whistle, take bowl off and gas is dripping out at a nice rate, jet is clean, tried it with the switch both on and off, choked with both starter fluid in the carb.

Rav2: I replaced the spark plug with an identical one (the original one was still fine I was 100% sure but I wanted to check it anyways). I did not gap it - I was pretty sure it was already gapped but I should check it. I guess my question for you is if I am getting a spark, based upon what you said the oil sensor should be OK.

Capncarl: I read about the compression issue but did not know how to test. I will check this out tonight when I get home from work.

Parnelli: I will keep you updated on the status - I am glad to hear someone else who is in the same boat...

My plan at this point is to check the compression- if it has compression and still wont start I will cash out and take it to the shop.

Thanks for all the input.

[annunaki]

In What Part of the Country do you reside?

I have found since moving to Florida from Long Island NY, that many times insects can be the cause of problems. They can get in and build nests in control boxes, air lines, etc. I have learned to insert pipe cleaners into the air couplings of all my nail guns due to "Mud Dobers" setting up housekeeping in them.

[chopnhack]

I have found since moving to Florida from Long Island NY, that many times insects can be the cause of problems. They can get in and build nests in control boxes, air lines, etc. I have learned to insert pipe cleaners into the air couplings of all my nail guns due to "Mud Dobers" setting up housekeeping in them.

Welcome to the swamp Annunaki :P then again, you are just a stones throw away from Okefeenochi :O

[parnelli]

Chirs64-

Any word on what the problem was?

[chris64]

Its been in the shop 3 weeks today. Still no word. When I dropped it off, I told the guy what I had done. He said he was going to pull the carburetor and soak it overnight in carb cleaner fluid. He said there were a bunch of tiny holes that you can barely see that probably got gummed up although the carb looks fine. I really wanted to try it myself after telling me that - but I figured I would let him take care of it. As soon as I get it back (if I ever do), I will repost what his solution was.

[chris64]

Just got a phone call from the small engine repair shop (after ~3 months). The problem with the generator is a stuck valve. Its going to be 225 to fix it. I really dont think it is worth it. I could use this as an opportunity to try and fix small engines - not sure what I am going to do yet. Looking back at capncarls replys - i may try the fogging oil or pulling the engine apart. I will slowly keep you posted on this saga. Probably will update this Spring. I have too many unfinished woodworking projects right now...

[parnelli]

Sorry to hear that. When the weather warms up I was planning to try and get mine running as well. I'll let you know when I start on it- maybe I can be of some help somehow.

[capncarl]

chris64
Is the engine a flat head motor like the a lawnmower or is a newer overhead valve design? Whatever it is should not take that much $$$. I unstuck a stuck valve on a pressure washer not long ago by removing the spark plug, rotating the piston down and about half way back up and pushing 10-12 feet of closeline rope into the cylinder. Carefully rotate the engine by hand to cause the piston to push the pile of rope against the valve. I heard it click when it broke free, pulled out the rope and put it back together.
capncarl

[jdon]

chris64
I unstuck a stuck valve on a pressure washer not long ago by removing the spark plug, rotating the piston down and about half way back up and pushing 10-12 feet of closeline rope into the cylinder. Carefully rotate the engine by hand to cause the piston to push the pile of rope against the valve. I heard it click when it broke free, pulled out the rope and put it back together.
capncarl

very clever!