[dataman19]

I have a Sears Craftsman Push Mower that will start fine - but will not stay running.
It is a 4.5HP with a pull cord start.
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NOTE: When I get it started it runs for about 5-10 seconds then shuts down. However (and this is a big however) If I pump the primer bulb - (the little rubber bulb that primes the engine to start) the lawnmower will keep running.
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Checked all the linkages - they are all moving correctly (at least I think they are - they aren't binding).
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Any suggestions...
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SECOND NOTE: It was running fine yesterday for about two hours. Then it died. I re started it - and after about 90 seconds it died again. I restarted it again and it ran for about 90 seconds and died, Today I tried again (after checking the oil and gas with a cold engine - just in case I read it all wrong when the engine was warmed up).. Started the mower - and it died within 10 seconds. Then I tried the pump the bulb trick and noticed I could keep it running.
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Pulled the fuel bowl to make sure there wasn't anything clogging it - it was fine and clean.
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Any Ideas???
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Dave

 

[bwdbrn1]

Don't know how old your Craftsman is, and if this is a new problem that has just come up following a summer of running just fine to mow your yard. I'd check the gas cap first. If the vent hole is clogged, it could be causing a vacuum in your gas tank that's not allowing the gas to flow.

 

[dataman19]

good idea bwdbrn1 - but I just have to ask (you can tell I'm a newbe) - wouldn't the tank vacuum prevent the primer bulb from keeping the engine running?
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Either way I will try this in the morning - the better half won't let me make noise tinkering with the lawnmower late at night..
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I'll let you know how it works out..
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Oh yea- Thanks for the help.
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Dave
dataman19

 

[Mark / Ohio]

Primer bulb would create several times more pressure (or vacuum) then the effect of gravity on the fuel.

 

[Brad]

Could also be some dirt in the carb that moves around a bit, only to get drawn into a passage and shut things down. Definitely a fuel flow issue. Wonder about the actions of the float as well. Moves freely?

 

[bwdbrn1]

Primer bulb would create several times more pressure (or vacuum) then the effect of gravity on the fuel.

Yep, the primer bulb would over come the vacuum. To start with, just unscrew the gas cap a bit and see if the mower continues to stop after a bit. If it does, then what Brad suggested might be the problem, something plugging things up in the carb.

 

[dataman19]

Okay gang... Removed the Gas cap - still stalling...
Also removed air Filter (which was understandably dirty)..
But it is still stalling...
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But I have additional Info::
Took lawnmower to a sears service center...
They complained that the product ID label was missing..
But still - they found out that it is a model 917.388531 and it has a tecumseh 4.5 HP engine...
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They looked at it and told me the repair estimate is more than the lawnmower is worth.. They told me the engine was shot (????).
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I brought it back home and I'm going to continue plugging at it till I get it fixed..
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Really,,, If the engine was completely shot (like they suggested) then why will it run when I pump the gas primer bulb???
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I really appreciate all of your inputs and this is why I joined this discussion group.. Thanks gang.So I'm still open for suggestions..
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Thinking about taking the carb completely off this weekend and soaking it in carb cleaner..
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Dave
dataman19

 

[bwdbrn1]

Hmmm...how old was this person who told you the engine was shot? Your mower is shot seems to be a common diagnosis in mower shops lately. Not knowing the product because certain labels aren't printed in large print on a card hanging from the handle seems to be an ailment going around too. I'd take a look to see if there is a small engine repair shop near you that works on Tecumsehs. My experience has been that the oldest guy behind the counter knows what the problem is and what to do to fix it before your done telling him what the engine is doing.

Anyway, your model 917.388531 is listed on Sears parts page here,
http://www.searspartsdirect.com/par...Parts/Model-917388531/0247/1500600?pathTaken=

The engine is part #70, and is shows it to be a model 143.044500. I don't find that on the Sears/Tecumseh cross reference list, but again, Sears shows it here,
http://www.searspartsdirect.com/par...l-Products-Parts/Model-143044500/0247/1503500

Like you said, take the carb off and give it a good cleaning. I use brake and parts cleaner in the aerosol can myself. It's easier on the skin than carb cleaner. Just make sure you point everything away from your face, and wear safety glasses. Never fails that that stuff shoots right back in your face when squirting it into a carb. Blow compressed air through all the openings and put it all back together the way it came apart.

If worse come to worse, a whole carb is available. And they say it's in stock.
http://www.searspartsdirect.com/par...7/1503500/P0212253/00001?blt=06&prst=&shdMod=

Good luck, and let us know what happens.

 

[dataman19]

OK Gang - I finally fixed it..
Being a Phd in Microbiology, Physics, Electrical and Mechanical Engineering, Communications, Data Engineering and general life experiences - I took the shotgun approach.. Also have degrees in Automotive engineering, History and Management. What can I say - started college in my softmore year of high school , went to MIT then Cal Tec and and continued taking courses throughout my 26-year stint with Government Service. Once I started taking college courses and getting excellent grades I got hooked. Not really smart - just have great comprehension and retention (also read at like 1800 words per minute - but hunt and peck when typing (never really took a shine to this typing stuff - but I hunt and peck at 45 WPM with two fingers on each hand ). But back to the lawnmower.
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Yes bwdbrn - the lawnmower tech was like 19-26 years old (probably an $8.00 an hour employee too). It seems as though the businesses now concentrate on low wage employees, mediocre service and high retail receipts - the repair shop is just a tool to get customers it to buy new...
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I lived in Europe (three of my Phd's are from the Einstein Universitate at Ulm Germany). Over there they fix everything until it literally rusts out. My associate and long time friend Deter owns the Sensheim Auto Technik Museum and he has an 1800's 3100Hp Steam engine that still runs. In fact almost everything in the museum (from rocket cars to old locomotives are maintained and operate like new - a fascinating place) But I'm off subject again...
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I soaked the carb and all the fuel related parts in a solvent that we developed to eat virtually anything crud.
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Also ate all the seals - So off I went to the sears parts people (who thought I was crazy buying all these little seals...).
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Put it all back together...
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Now it runs better than it ever did.
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Oh yea - I had to play with the float to get it to work properly
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I want to thank all of you for your excellent inputs...
Keep up the great endeavors...
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If you ever need anything my email is [email protected]
keep in touch
Dave R. Mason
dataman19

 

[Brad]

Hey, Dave, glad you got it fixed!

By the way, my son has a PhD. in Mathematics. Pretty smart fellow. And here I am, just a high school graduate. But, just the other day, I was talking to him about his work (He teaches Mathematics at a college in the Chicago, IL area). He was telling me about all the stuff he was going over with the kids in his class. I asked him to tell me one of the equations that they were working on. He said, well Dad, I was telling the whole class that "Pie Are Square", and they just weren't getting it. I said to him, "Well it's no wonder! Everyone knows Pie are Round, Cornbread are Square".

(He absolutely hates it when I tell that joke.)

Now, back to lawnmowers. By all means, Dave, visit on a regular basis. What you learned will be very valuable to a new member trying to get their machine running properly, and you have the experience to assist them in their endeavors.

 

[Mark / Ohio]

Dave, good to hear you have it solved!

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Being a Phd in Microbiology, Physics, Electrical and Mechanical Engineering, Communications, Data Engineering and general life experiences - I took the shotgun approach.. Also have degrees in Automotive engineering, History and Management....

This is JEOPARDY! - Be a Contestant - Contestant Searches

I could use some of your recollection speed and retention. I have interest in all those studies you mention but the ole brain just runs too slow remembering where the files are located to go for a degree. I stopped at an Associate in Electronics only two years shy of a full EE. I regret it now though given the modern cost of college compared to 1984 and wondering what might have been. But the math for a full EE scared the heck out of me. I could do the calculations and figure out possible ways to solve problems. It was correctly remembering all the formulas and other specific data that gave me fits.

I ran into an old customer of mine today while shopping I've done occasional service work for over a 20 year period. Finally remembered his name an hour later when back home. Yet at the time I could tell you what his house looks like inside and out and drive you to it. Weird how the brain works at times.

 

[geogrubb]

dataman;
The next time the engine starts acting up, clamp off the fuel line and remove the bowl nut(main jet), there are sevral designs, however most have a tiny hole that is almost invisible next to the threads near the top, clean the tiny hole, I use the wire from a twist tie, it almost always solves the problem. Have a good one. Geo