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Young collector
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9 Posts
Discussion Starter · #1 ·
I have a Gravely walk behind machine i believe has the 6.6 horse power motor (large slanted spark plug and under "hood" air filter). The problem i am having is not firing with only gas. With Either it will pop out the exhaust but wont fire over. the starter may not be turning fast enough but im not sure. any pointer with getting this old beast running will be much appreciated!
 

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youtube.com/5Tractorguy
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495 Posts
I have a Gravely walk behind machine i believe has the 6.6 horse power motor (large slanted spark plug and under "hood" air filter). The problem i am having is not firing with only gas. With Either it will pop out the exhaust but wont fire over. the starter may not be turning fast enough but im not sure. any pointer with getting this old beast running will be much appreciated!
Sound like you may have a weak spark. May not be a hot spark enough to fire on the gas. Try cleaning the points in the magneto. The gap is .015 for them. I usually use 400 grit or finer sandpaper. Works great.

You should post your question over on the Gravely/Ariens forum HERE. There's a whole lot of people that can help you out there!
 

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Young collector
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9 Posts
Discussion Starter · #4 ·
spark is hot and strong and will jump a solid inch and still stay bright blue.
 

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Legend in my own mind
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210 Posts
Does the magneto click? If so, it should click very close to top dead center on the compression stroke> Compression is another required piece in it running. Does it blow your thumb off the hole with the plug removed as you turn it over?

Next is it getting fuel into the cylinder?

Post back.
 

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Gravely Model L Guy
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464 Posts
Check to see if it has compression and look to see if the points in the magneto are crusty or dirty, if so clean them up or if they are really bad replace them. I had a tractor that did the same thing and a magneto rebuild did the trick.
 

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Premium Member
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5,381 Posts
spark is hot and strong and will jump a solid inch and still stay bright blue.
Sounds good so far. Per some of the other folks:

Timing
Compression
Mixture

If you search this forum you'll find lots of threads about timing. Basically, you should here the impulse coupling of the mag "snap" right about at TDC. Take the plug out, lay it on the head hooked up, and turn it over slowly. You should be able to look down the hole and see the piston top out. If you get a snap and a spark right about at TDC, you should be all set, at least enough to get it running.

Sounds like you have an electric start. For compression, take the chain off, disconnect the mag, and turn it through by hand. You should feel a very noticable resistance on the compression stroke. On a good tight engine, it's really hard to pull it through by hand. If you're not feeling a solid compression stroke, you may need a head gasket, or more likely, one of the valves was stuck open. Might be still stuck or seat may have corroded.

For fuel, verify that you're getting fuel to the carb, by pulling the bottom plug out. If it's dry, you've got an obstruction in the tank, or in the line, or the needle valve isn't opening. If you've got fuel to the carb, make sure the main jet is open about the right amount. If you haven't already perused www.oldgravelys.net and downloaded an apropriate manual, please do. For the cast iron carbs, you want the main open 2-3/4 turns or so. But find the manual that's closest to what you've got.

These are very simple engines, there's only so many things that can go wrong.

Good luck, post back, and :wwp:
 

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Young collector
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9 Posts
Discussion Starter · #10 ·
Never even thought of a stuck exhaust valve but it seems to be the culprit. no muffle and sitting for a long time point to that. The spark is timed right and carb is working good after a cleaning. no compression tho now that i put a tester on it so i will pull the head and take a look. Thanks for all the help! also as a side note, when the tires are of the ground, when you crank it over it turns the tires and blade, but with tires on the ground, nothing spins. and were is the lever to turn the attachment off?
 

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Gravely bug bit.
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8,737 Posts
Never even thought of a stuck exhaust valve but it seems to be the culprit. no muffle and sitting for a long time point to that. The spark is timed right and carb is working good after a cleaning. no compression tho now that i put a tester on it so i will pull the head and take a look. Thanks for all the help! also as a side note, when the tires are of the ground, when you crank it over it turns the tires and blade, but with tires on the ground, nothing spins. and were is the lever to turn the attachment off?
Depends on how it is setup but there will be a lever on the front rigth behind the attachment or a rod coming back to inline with the tank on the left side. Sould have an open ended loop on it. Push it forward to stop the attachment.
 

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Old Iron Connoisseur
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2,783 Posts
Attachment control lever is at the front of the tractor in the very front casting. Should be labeled In and Out. If it has the long handle that runs up the left handle bar, make sure it's pushed forward and that should disengage the PTO.
 

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Gravely Model L Guy
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464 Posts
Never even thought of a stuck exhaust valve but it seems to be the culprit. no muffle and sitting for a long time point to that. The spark is timed right and carb is working good after a cleaning. no compression tho now that i put a tester on it so i will pull the head and take a look. Thanks for all the help! also as a side note, when the tires are of the ground, when you crank it over it turns the tires and blade, but with tires on the ground, nothing spins. and were is the lever to turn the attachment off?
Thats because the clutchs are dragging. Due to gravity when in "nuetral" (gravelys TWTs have no true nuetral) the lever that operates the F/R clutch slides forward and rubs on the clutch cup. It is not enough force to propel the tractor when on the ground but when it is jacked up it will turn the wheels.
 

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Young collector
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9 Posts
Discussion Starter · #14 ·
i have looked all over the left side of this thing for a lever and found nothing. could someone post a pic of it? and that makes sense about the clutches thank you for that.
 

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Gravely Model L Guy
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464 Posts
i have looked all over the left side of this thing for a lever and found nothing. could someone post a pic of it? and that makes sense about the clutches thank you for that.
Then look on the front of the tractor directly before the 4 bolt hook up for the attachment. There should be a lever there that says in or out. Since it is electric start that lever would be under the battery box.
 

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Gravely1964
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4,151 Posts
i have looked all over the left side of this thing for a lever and found nothing. could someone post a pic of it? and that makes sense about the clutches thank you for that.
Ok I made a late night run to my shop to get these pics. Pic one and 2 shows the lever in the out postion on a tractor with a battery tray. pic 3 was for a for a reference to the location of it.
 

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Premium Member
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5,381 Posts
Huh. First time I've see one with electric start, without the remote PTO setup.

Re the valve, there are old documents on oldgravelys.net about freeing them up. Lots of times you can just take the head off and give the top of the valve a few taps and it'll drop. You still may have issues of corrosion on the seat though.
 

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Gravely bug bit.
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8,737 Posts
Huh. First time I've see one with electric start, without the remote PTO setup.

Re the valve, there are old documents on oldgravelys.net about freeing them up. Lots of times you can just take the head off and give the top of the valve a few taps and it'll drop. You still may have issues of corrosion on the seat though.
They are around but after you use one, you know why there are so few araound.
 

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Premium Member
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8,841 Posts
I am trying to figure out what the white thing is where the bolt/pivot point is supposed to be. Is that an indicator showing where it was located?

It looks like the body has the pin for the remote PTO shifter, it is just missing the fasteners, spacer, arm, and shift rod.

The handle gets turned 180 degrees to engage the front PTO.
 

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Gravely1964
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4,151 Posts
Huh. First time I've see one with electric start, without the remote PTO setup.

Re the valve, there are old documents on oldgravelys.net about freeing them up. Lots of times you can just take the head off and give the top of the valve a few taps and it'll drop. You still may have issues of corrosion on the seat though.
I have three like this. Agreed on being a major pain to use Don! On my dads tractor he took and had about 12 inches of flat stock welded on top with a bit of a bend in it so he could use it easy turn it in and out. If ya want pics I still have it.
 
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