105 won't start low compression stale gas what do I do first?

[MrChic]

Hey all, thanks for all the advice. The battery is new, only a few months. I will charge it tomorrow just to be sure.

I drained most of the gas from the tank through the petcock with the glass bowl off. How do I get all the gas out? It looks like there is a little more in there. Do I need to take the tank off?

When I was fooling with the sediment bowl, I noticed if I tightened it real good and opened the fuel petcock, gas wouldn't flow. If I loosened it, then it would start flowing and leak. There was not alot of gas in the tank at this point. Could this just be because of the gravity feed of the fuel system?

I have a new plug and I will try it. As far as laying the plug on the head. The head is not really accessible, it is covered by the shroud/sheetmetal. Am I trying to ground the plug? Is placement on the engine somwhere critical to do a good spark check?

I maybe headed to the dealer this weekend for new front wheel bearings, so maybe I will pick up a coil and points. Is there anything else needed for a good tuneup? I have a new plug, oil, and air filter. Should I get a new plug wire? What exactly is the condensor?

Sorry for all the questions. I can handle the chassis type stuff much better on my own. Thanks for all the help.

[Yosemite Sam]

Originally Posted by MrChic

The battery is new, only a few months. I will charge it tomorrow just to be sure.

Good idea to charge the battery.

Originally Posted by MrChic

It looks like there is a little more in there. Do I need to take the tank off?

Try taking the whole fuel bowl assembly off of the tank, let it drain and look inside the tank for rust, crud, or what ever. Then take the fuel bowl assembly apart, clean it well and blow through it. If the tank has crud in it you will probably want to take it off and clean it out.

Originally Posted by MrChic

When I was fooling with the sediment bowl, I noticed if I tightened it real good and opened the fuel petcock, gas wouldn't flow. If I loosened it, then it would start flowing and leak.

Not sure I understand this part, almost sounds like the vent in the cap is plugged or the tank has crud in it.

Originally Posted by MrChic

As far as laying the plug on the head. Am I trying to ground the plug? Is placement on the engine somwhere critical to do a good spark check?

Yes, you are trying to ground the plug, placement is not important, as long as it gets ground and doesn't ignite any fuel.

[rmunro]

[QUOTE=Merk;15205] The starter will hog the most current....sometimes leaving little to no current to fire the spark plug.



I had that happen to me. I spent a long time going in wrong direction before I figured it out. Bad armature.


And it happened suddenly.


.

[MrChic]

Not sure I understand this part, almost sounds like the vent in the cap is plugged or the tank has crud in it.

No the tank, looks nice and clean. Maybe I will get a new gas cap while I am at it.

Probably should pick up a carb kit too. Wow my shopping list is getting long.

[ol'George]

If the Carb float bowel is full of gas, the needel valve is seated, or closed if you perfer.
And is basically saying I don't need any more fuel in me.
so you will see no fuel flow to the carb looking through the glass bowel,because the line is closed off by the needle valve. if it can't get out the end, it can't flow.
when you loosen the glass bowel, you are allowing fuel to flow because there is a leak in the system so to speak..
Now if the needle valve is stuck closed in the carb. with or without fuel in it that is a different story.
first and formost see if you are getting spark and we will talk you through it.
Do what you like, but I would not get in a hurry to purchase a coil, condenser, points just yet, lets see what it needs or is wrong, most likely is is something simple. and you are learning "process of elimination".

Many Many times a simple thing like the points having a slight bit of corrosion
or rust will prevent them from working and with a little cleaning all is well.
this is the fun part, finding the problem, not throwing parts at it til it runs.
Growing up in the early '50's we didn't have $$ to spare so we learned to spend only where needed.

[Yosemite Sam]

ol'George is exactly right...

I used to try to explain to my ex, that throwing money at every problem that comes along is not always the best plan of attack.

ol'George, is also right about the gas flow issue, I never thought about the other end of the hose being attached to the carb, I just figured that it had already been taken off.

And I wouldn't buy a new cap, IH wants about 9 bucks for one, just take yours apart and clean it out, or try blowing through the little hole in it from the outside to see if it's clear.

[MrChic]

Ok, my battery is good, my plug wire is good (I checked, no resistance), my tank is clean and flows, but I will check the cap. So I need to check my plug, coil and points. Points I think I got. What is the best way to clean them? Should I steal one of my wife's nail files? Is there a way to test the coil? The ground for the coil is the one connected to the block correct? The one that goes to the starter gen, is that the hot lead? I am going out to get fresh fuel and put some sta-bil in the can first (Thanks Merk) and I really hope I can get this figured out tonight.

[Yosemite Sam]

The Neg (-) side of the coil goes to the points, that is the same side the condenser is hooked to.

Nail file will work...

If you need to check your coil... http://www.onlycubcadets.net/forum/showthread.php?t=11

[ol'George]

Power to the coil,
There is still a debate as to if the hot wire (usually from the ignition switch) is connected to the plus or minus markings on the coil, and I don't want to get into a debate. it will work both ways.
I prefer to hook it to the + marking on the coil.( some coils are not marked)
The other wire - goes to the points where they are grounded/ungrounded as they close or open, thus completing the circuit, providing ignition or "spark"
While the points are closed, the power is building up in the coil, it does this instantly.
It is when the points open, that the spark occurs, not when they close.
a person can turn on the key, or put a hot lead to the coil + and watch a spark occur at the spark plug by opening or closing the points with your finger, popsicle stick, pencil or anything else non conductive.
Turning the engine over will do the same thing either by hand or using the starter.
This will tell if you are getting spark.
You will at most times see a small spark, at the points, while the points are closing or opening, this is normal.
It is the condensers job to keep this small spark to a minimum, to prevent the points from eroding greatly or prematurely.
The points should have a gap of say .016-.019 ( it varies) when pushed open by the cam and the points need to be clean so they make contact with each other, when closed
yes they can be lightly cleaned with a small nail file. the proper way is to use a diamond dusted point file, but most folks don't have one.
Sometimes something as simple as a piece of paper carefully pulled through the points will remove oil or contamination so they will make good contact. be careful not to leave residue/ fuzz etc.to prevent good contact.
I have found bugs that love to buld a nest in points, carb vent holes,
gas tank fill vent cap holes. just most anything that they can plug up.
it seem at times it is their destiny to make mans life hectic!!
ol'Geo.

[MrChic]

I AM AN IDIOT!!! Please don't kick me off the forum. I should not own tools let alone Cubs or anything gas powered. To start my tractor I have to jump from the battery across to the starter generator. Well you still need the key in the run position to get spark, so when the key is sitting on the tunnel, there ain't no spark. I learned alot from the experience though. I learned that putting the points cover back on a narrow frame is a pain in the butt. Now gas is pouring out of my carb, so I guess it is time to jump into carb removal/cleaning/rebuilding. Cross your fingers. But once that is done, she should fire right up.