Craftsman lawn tractor starting problem

Rivets

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Yes, connections, solenoids and starters could cause this problem, and if you don't want to check the valve clearances then you can start replacing each one of these parts. Sorry, that's about all I can help you with. Bye.
 

motoman

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I haven't tried jumping the tractor off of a car. Like I mentioned on my first post, if I charge the battery up to ~13.5 volts then the tractor starts up fine. I do notice that the engine turns over faster than it does at 12.6 volts. It may be due to the compression release not working right as some have mentioned - if so then I guess the higher voltage to the starter overcomes the failure of the compression relief to release pressure.

But back to my original question - could a bad connection, bad starter solenoid, or weak starter not also cause this problem. Do starters ever weaken over time? Just trying to consider all possibilities.

Some basic stuff about batteries I have found useful. If you don't have one buy a battery hydrometer with the tip narrow enough to go down into each cell to draw out the electrolyte for a reading. The thing looks like a turkey baster-squeeze bulb on top. The clear glass tube will tell you if the battery is charged. This is better than a voltage reading. One volt as in 12-13 v is meaningless as batteries can develop a "surface charge" which is high. With a hydromerter and charger you are armed with the best to evaluate the battery. If a bat won't come up on the hydrometer after trickle charge it may need replacement.

If anyone is interested in a poor man's load test , ask . :biggrin:
 

pugaltitude

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Used to use hydrometers all the time.
Problem is you cant test sealed units and sometimes a battery has lack of residual power but volts appear to be ok.
I then bought the older, smaller version of one of these and get an exact reading in 6 secs.
As a business iv sold a lot of batteries and customers see the readings to then know that the battery is faulty.
ACT GOLD-PLUS 6/12V Intelligent Battery Tester
 

motoman

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Pug, ok you're ahead of the curve...can't tell on this forum sometimes if I'm talking to a pro... Anyway I have never invested in a "pile load " tester. As you probably know a huge resistor simulates the draw on starting etc. Harbor Frt has em but perhaps overkill for a home hobbyist. What I have done sometimes is the po'boys load test of battery. Hook up a VOM to the bat posts and crank the engine for about ? 5 seconds? ( as I recall) while reading the voltage to see if voltage drops during cranking. Should hold . Regards
 

Elias40

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Electrical can be very tricky and fool even the best technicians out there.

The next place(s) to check are all the wires, and their connections. Make sure the big ground wire is secured tightly to the engine block- usually oil and crud accumulates around that area and eventually insulates the connection to where not enough current will pass. Check the starter bolts-attaching it to the engine. make sure they are tight.

The only thing left besides the starter, is the solenoid. Over time the contacts on the inside of the solenoid get so worn down, that there is not enough copper left to allow enough current to flow out to the starter.

Having enough voltage, yes, is important, but starting systems on most devices including big trucks relies more on having the most current. This is the reason for trucks having more than one battery.

Your lawnmower is no different. same principal from the smallest to the largest remain the same.
 

paejkirk

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Sorry Rivets - didn't mean to offend. I had such "tunnel vision" that it must be an electrical problem that I couldn't fathom that a valve clearance problem might be the cause of my problems. I have watched some really good videos on YouTube that show how to adjust the valves on a B & S engine. It looks pretty simple so I think I'll give it a try. One guy on a video said that you really need to check the valve clearance on a B & S engine yearly because they can come out of adjustment. If the valve clearance adjustment doesn't fix the problem then I will start troubleshooting the starting system.
 

motoman

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Sorry Rivets - didn't mean to offend. I had such "tunnel vision" that it must be an electrical problem that I couldn't fathom that a valve clearance problem might be the cause of my problems. I have watched some really good videos on YouTube that show how to adjust the valves on a B & S engine. It looks pretty simple so I think I'll give it a try. One guy on a video said that you really need to check the valve clearance on a B & S engine yearly because they can come out of adjustment. If the valve clearance adjustment doesn't fix the problem then I will start troubleshooting the starting system.

There are so many pros on this site that sometimes things sound simple that aren't so simple. IMO one of them is adjusting mechanical pushrod valves. Perhaps I should put on my flame suit but... You must be patient when you try this. The adjuster hardware is small but the wrenches used are fairly large box end wrench and either screw driver or torx driver. Then there is the flat feeler gauge which is used to determine the clearance you select. Unless someone out there has grown a third hand you determine the clearance after slipping the e.g. .006" gauge between the valve tip and the rocker tip, snug the adjuster screw just right and then lock down hex nut. When you lock the hex nut (very light torque) you probably will also tighten the screw too tight so that when you recheck the valve adjustment is too small.

So you allow for the unwanted tightening by going loose on the clearance and try again.
You should also check that you have the clearance correct with "no go" feelers above or below the desired clearance ( you want .006" so see how .007" or .008" feels , or maybe .005" or .004." ) Making this tricky is the fact that you can "force" a feeler gauge above the "actual" clearance thru the gap. This is especially easy to do with the weak valve springs on these small engines.

Final comments: The ingenius "stud rocker arm" used on my Intek (corvair, chevy etc) wobbles when torqueing which can be bothersome. Raise your tractor engine up as far as you can - eye level would be best (joking a little). If you have never done this before be patient and expect to spend a lot of time at first. Way back I think I remember hand held OHV adjuster tools , but I am not in the bis like some . Savvy forum members chime in . Flame suit is on.
 

paejkirk

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In the YouTube videos they were talking about .003" or .004" being the proper valve clearance - now, I'm a little confused because Motoman just said to use .006". What is the right size feeler gage to use?
 

pugaltitude

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Assuming single cylinder and model is a 31 or 33 (numbers on rocker cover)
They will be .003"-.005" inlet & .005-.007 ex.
 

motoman

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paejkirk, sorry , didn't mean to kick out what looked like a universal clearance.

I guess I should also state that finding TDC (or wherever the mfg says) is important before the valve adjustment. Each engine is different and the spec should be consulted. Sometimes they give cold clearance only,sometimes hot and cold (different). Hope all this talk does not discourage ; try it and it'll get easier, but be your own critic (check after tightening). Do not do what I once did trying to quiet noisy tappets by too tight on exhaust valves-burned 'em out. The opposite might also be true if somehow drastically large clearance is set a pushrod could fall out of its "dimple" at the rocker (speaking here again of my Intek 24) From what I've read most times the pushrod lays obediently loose for you find it and reinstall it, but my Intek somehow ate its pushrod when it passed into the sump.

Just be careful and double check after tightening with your feeler gauge. When I take off the valve cover and rotate to TDC I usually grab the rocker and wiggle up and down. You normally can detect the cold clearance and then , of course , measure it .
 
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