Lever
wlcox@ipa.net
Join Date: Jul 2003 Posts: 9 West Central Arkansas |
2002-09-18 42599
Hi All:
I found a lever under the left side of my dash that's connected to the top of the engine. It appears to turn rather than push in or pull out, so with the motor running I attempted to turn it. I had the hood up on the tractor, and as I slowly turned this lever I heard something in the motor start making a noise like a couple of gears trying to engage or something and begin to feel the vibrations resonate through this lever. I immediately turned the lever loose, and haven't tinkered with it since. I don't have a manual for this tractor, and I am curious what this lever is, and what it does. Can anyone give me some insight here? Thank you.....Wes
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Lever
DavesTractor
Join Date: Jul 2003 Posts: 148 Red Bluff, California |
2002-09-18 42600
What model of Yanmar do you have? Sounds like you might be dealing with the compression release, but give me a model number and I'll check it out. Dave ....
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Lever
wlcox@ipa.net
Join Date: Jul 2003 Posts: 9 West Central Arkansas |
2002-09-18 42604
Model is the M1500D Curious how I would use this lever. Is it for cold weather starting? If so, how do you use it? I've not had this tractor long, but I sure do enjoy using it. Thanks Wes ....
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Lever
DavesTractor
Join Date: Jul 2003 Posts: 148 Red Bluff, California |
2002-09-18 42609
I don't deal much in the "00" Yanmars, but I am fairly certain that it is the decompression lever. If it were not on the tractor you would probably never miss it, but even so, it is handy to help with starting when you have a low battery or possibly it could help some in cold weather. I live in California, so I'm not all that savvy on cold starts. It can also be used to kill the engine. Yanmar recommends that you shut down the engine with the fuel shut off (throttle all the way forward)and I agree and wouldn't use the decompress to shut down unless it is an emergency and you can't get to the throttle or it is not functioning correctly. Some "00" modesl have thermostart to assist starting in cold weather. It works well. One other use for the decompression lever is to pull it out after you change and refill the engine oil but before you start the engine. Spin the engine over without compression to top off the filter and get oil where it should be. ....
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Lever
Peters
Join Date: Feb 2002 Posts: 3034 Northern AL Pics |
2002-09-18 42611
I would also think it would be useful in priming the fuel system if you change filters or run it dry. ....
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Lever
TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley |
2002-09-19 42625
Decompression levers are very handy for positioning the engine to make timing adjustments without having to work against compression or removing an injector or glow plug. The way they're used for cold starting is to engage the starter with the compression released on and then turn it off after a moment.
The starter motor runs a bit faster with the compression released and then inertia gives a power stroke or two at a higher rmp than the battery alone would drive it. As Art says, it's very handy with a low battery. However, excessive cranking if the engine doesn't fire washes oil off the cylinder walls, dilutes engine oil etc. The same is true with or without compression release. I don’t need one on my Ford but I’m sure happy my chainsaw has one. I’m left-handed and there are no left-handed chain saws. I need all the starting help I can get.
....
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Lever
kayssupply
Join Date: Posts: 1 |
2002-09-21 42755
The compression release is also used to build oil pressure before a cold start. by the book ,you hold it in until the oil pressure light goes out before you release to start. ....
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Lever
TomG
Join Date: Feb 2002 Posts: 5406 Upper Ottawa Valley |
2002-09-22 42767
That's a good comment and a use that I had forgotten. The throttle should be in the kill position while cranking though to keep from injecting a lot of fuel before the oil pressure comes up.
I've even heard of some people who take oil pressure at start up seriously enough to rig external pumps that circulate the oil before cranking the engine. Of course, it doesn’t take the pressure as long to come up for filters that have anti-drain back valves, or so I’ve heard. ....
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Lever
Peters
Join Date: Feb 2002 Posts: 3034 Northern AL Pics |
2002-09-22 42787
Damage occurs at initial first firing with out the oil pressure in the journals. Air craft engines crank until the pressure reaches operating pressure and then the magnitos kick in. An accumilator is used on race engines to prolong live and allow you to run with a dry sump, for increased power. ....
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