Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

I just recently purchased a MTD Snowblower with  8hp Tecumseh Engine on it, for $200.00 off of Craigs List.

It was running fine until I put it up on its casining to chech for it being lubed on it's drive gear. Since then it

starts up but will also stall out when I switch it off from full choke, 1/2 choke, then to no choke. It then will not start

even with using the electric starter. I have been online and have read alot of forums on the Tecumseh motors

and have found this one to be the best.   ( Richie ) your comment  being the first one I had read on adjusting the RPM'S

on your engine. I had in other forums have heard of these motors have a common problem of staring issues.

Mostly directed towords the carburator. My brother has the same HP Tecumseh on his Snowblower and it starts

from year to year with out running any Sta-bil in it before parking it in his garage for the next 10 months!!!

Can anyone give me any direction on my next step.

Here is some additional info. 2003 on owners manual, Spec- 155693X HMSK 80, D.O.M. 03325CH0708

Thanks,

Bud

Bus708,

THANKS for the input!

After getting the carb back I put it on and is running fine now.  I believe like yourself to run your engines with clean oil.

 ( I keep up on all my equipment as well as keeping it out of the weather in a dry place. )

So when I got it home I checked it and it was dirty. I changed it immediatly. I also drained the tank and put the inline  " shut off valve "

in. I figured take all the possible causes of dirty gas out of play. I have run it  ( with it being 90 degrees out with my wife shaking her head )

with good clean gas and some Sta-bil in itfor couple of time so there should be no gas laying in the bowl. I have run

it dry with valve shut off to make sure all gas is burned.I have a gas drain at the bottom of my bowl. Would it be just as good

too drain it there as runnning it dry?

As you said these engines should run with out a hitch. I was getting frustrated in thinkin the same thing. I also was not going to

deal with it when I go too use it, and it doesn't work!

THANKS AGAIN!

Bud

I miss the old Tecumseh finger pushbutton fuel bowl drain.....  Anybody else misss those too?

-Friiy

friiy wrote:

I'm back!!!

Guy's I tried to start the snowblower after a couple of months. It again is not stay runnning and once it

stops, will not stay running any length of time. I had it running the other day and went inside to get something

and it shut off. I was on med. idle and sounded like it was going to be fine. Then it shut down.

The only way I can get it to some what start is by pushing the primer about 10 times - then it starts up

and stalls out again. What the H is up with it???????? Do you think I should replace the carb?????? Or just

rebuild it??? To me it souds like it is starving for fuel. This getting REAL frustrating to say the least!!!!

With the cold weather on the way I want to get this thing running the way it should be. All the info is above on

the snowblower.

Thanks,

Bud

   Yes, it seems like it’s not getting gas.  It could be the spark plug or plugged gas cap vent but those are remote from your description.

   You mentioned above the carb was dip cleaned.  If that was an overnight dip in a solvent then it’s probably clean but may have some crud possibly from the inlet line.  

   Since you have to prime 10 times it could be a float adjustment, the needle sticking to the seat or the high jet on the bottom of the bowl in too far.  After 10 primes you should have smelled gas and had gas dripping out of the carb throat.

You could try these things:

First:

Screw in the low idle jet to see if it was set at one turn out.  

Screw in the high jet at the bottom of the bowl to see if it was 1 ½ turns out. 

If the man jet was closed back it out 1 ½ and try starting again.  Give it 3 primes, full choke and 4 pulls only and it should start and run. If not take out the spark plug and it should be wet.  If not then there is a block someplace.  If it’s wet, dry the plug, wait 10 minutes and try again with less choke and less prime and repeat if wet.  If it was dry step 2.

Second:

   Partly unscrew the bowl nut and have a container handy.  Gas should flow out and keep flowing out.  If not then you probably have some big crud in the line or in the float needle area.  It could be due to a stuck float needle up in the hole where there is a rubber seat.  Tap the side of the carb and see if that frees the needle.   If no flow then take off the bowl and lower the float by hand and gas should flow out.  If not then you have big crud up in the seat area or in the line.  Pull the gas line off the carb line and insure gas will flow out freely.  Put the gas back in the tank and flush gas through a few times.  Look at what comes out.

   If gas flows freely when you unscrewed the bowl nut a little screw it in again and wait for the bowl to fill and unscrew it again to see if it still flows freely.  If yes then take off the bowl, check for dregs and clean out the bowl nut.  There are usually two holes in the bowl nut.  A big one at the base and a very tiny one up higher by the last of the first thread run from the base.  Stick a small wire in there to punch out any blockages.  

Work the float up and down slowly to see if the needle is sticking up in the hole.  Sometimes the float needle will stick to the rubber seat up in the hole.  You can hear it snap free if it's sticking.  That’s where gas comes in from the line.   

 The float should be about parallel to the carb rim and gasket when you push the float up and the needle just seats.  If it’s not parallel move the float tang to correct.

 

Put it back together and check the primer.  Pull the primer line off the carb and punch the primer bulb with your finger over the primer line end.  You should feel a slight puff.  If none then you could have a cracked line or primer bulb.

Give it 3 primes, full choke and 4 pulls only.  You should get started and run.  No, check the plug.  If wet, repeat with less.  This probably won’t happen.

 No start or starts and craps out,you’ll probably have to pull the carb and go through it in detail checking the seat and float adjustment and a brief cleaning with a can of carb spray.  It probably won't need a kit.

 

   The most likely thing is the float is not adjusted, sticking or the seat is in wrong.  The proper check for the float is done by turning the carb upside down and adjusting the float tang to be 11/64’s from the rim just as the needle seats.  That can be a pain so you can just adjust the tang a smidge away from the float to pull the needle off sooner without pulling of the carb off. 

    The seat might be in wrong but you need a tool to get it out easily.  You can work it out with a pick though.  It has a ribbed side and a smooth side.  It should go in ribbed side first. 

THANKS for the reply trouts2.

I   decided to try and change the spark plug. I hadn't when I brougt it home like I did with the oil.

I had pulled it out to check if it was getting spark when it wouldn't start. So, I  thought it may fail

after running a bit and take that out of the equation. I got on about an hour ago and put it in and

it started right up. I ran it about twenty minutes with out any problems - both idling and at maxed out.

It ran fine. I shut it off a couple of times  to see if it would start and it did with out any

problems. I came in and let it cool a bit and to see if there would be any issues when I went out to try to

start it again. It would not start with the choke off, only when it was on. It started for about twenty seconds

and would not start again. Did not even sound like it wanted too!. (  I did not primer it ). I took out the

plug to see what it looked like and it looked fine. Checked for spark and had it. Just for $#%*s and gigles

I put the old plug in and it started but soon stalled out again. Almost like someone was flipping a switch.

I don't understand why it would run fine and then all of a sudden not!!!! I could see it at first it ran for a short

period and then shut down, but 20 minutes?!?!?!?!? If it was a fuel/ float problem wouldn't it always be and issue????

Could it be that something gets hot and causes it too not run.......just asking because it does not make any

sense to me at all!! I didn't take off the carb yet and fool with the float. I guess that is my next step.

Would love some feedback.

........do you think I have a female snowblower??????????? .........just asking! LOL

Bud

   Keep the new plug in to eliminate bad plug.

   Keep the gas cap screwed on very loose to eliminate a gas tank vacuum problem.

   I don’t think it’s either of those but eliminate them anyway.

 

   You ran once for 20 minutes.   Then it will start, run for a short time then stall out. 

 

>>If it was a fuel/ float problem wouldn't it always be and issue????

 

Stay an issue probably but not necessarily in the same exact way consistently.  The needle can stick for a while then not stick.  The float adjustment could be somewhat close.

  Dregs can be in the bowl and get swept up with the gas flow, block a hole then fall back to the bottom of the bowl.  They can be around and not get swept up then later block a hole. 

 

>>Could it be that something gets hot and causes it too not run.......just asking

    If running for a long time and crapping out happened all the time then it could be other things heating up.  You mentioned it happened once then went to starting and stalling quickly.

 

>>I didn't take off the carb yet and fool with the float. I guess that is my next step.

Probably the best next step.  It does not seem like anything is broke or screwed up other than an adjustment and or further minor cleaning.

I'll have to pull the carb off then. I will try to follow your instructions on the adjustment of the float

and the others that you had mentioned. I'm pretty mechanically inclined but have never fooled

with adjustments on a carb. , other than for idle, but will give it a whirl. It's one of those things to see

and have some explain what they are talking about. Then reading something and understand exactly

if you are doing it right or not......ya know.

I've looked into carbs for this thing if I have to go down that path. They are around 80.00.

Does that sound about right??

It just drives me crazy that my brother has no problems with his and does not do any preventive maintinece

on his and his starts right up, and with no problems! He does change the spark plug though.

So, I'll take off the carb tomorrow and see what happens. I have off tomorrow and Wednesday.

Thanks again trouts2!!!

Bud

   There are some things listed above you could do before pulling the carb which could eliminate the need to pull it.

 

   The adjustments and steps above probably seem complicated because you are not familiar with the carb but they are actually pretty easy.  Backing out a screw 1 ½ turns is not difficult or cause you to skin your knuckles.  Watching a needle drop with lowering the float won’t make you throw up. 

 

   Your carb may or may not have the low idle adjust as a settable screw versus a screwed in jet with no adjustment.

 

Your carb goes for approx 60-80.  Suppliers may have the original or a replacement. The replacement may not have settable jets.  It would probably be better to have your original carb working than a non-settable replacement.

 

   Your brothers not doing maintenance on the engine and having it start and run next season is a matter of luck.  It depends on how much gas was in the tank at storage, if there is a shutoff, temperature of the storage place, ventilation, moisture & etc.  Some conditions will cause a carb to gum up quickly and others not.     

   Just say a person left a half a tank of gas, did not have a shutoff and left it in a small shed in the sun.  Chances are high the gas in the bowl will evaporate quickly and be refilled over and over leaving a heavy brown gum inside.  Another person could leave a half a tank of gas in, shutoff the valve and store it in a shed under a tree.  He might end up with a very thin gray/green film which will not cause a problem.  The gas could even stay good and fire up the next year with no problem. It would probably take several years before the buildup became a problem.  There are lots of factors to just how varnish builds    

Trouts...OT....but let me pick your brain. Sounds you work on unmaintained OPE equipment.

I still need to verify the body/condition of the unit.
It's a Honda 621, and the gas was left in there for 2 years. It has not been started since then.

I plan to do a physical check up, etc. I am kool with replacing belts and such.
Afterall, it's a old machine....

I'm probably going to end up replacing the carb on it instead of doing a soak & clean.
Just short of the varnish, is there anything else that might surprise me on a older machine.
I think the only issue that may present itself is the varnish

I'm thinking new carbs, paddles, scraper bar and drive belt.

Well trout2

I just went out and started it up with the old plug still in. It started right up. I could hear it was running a little

ruff so I shut it down and put the new one in. and it kicked off right away. I ran it for 15 mins and then shut it

off and went back inside for about 20 mins.,  - came out and it started right up again. I ran it actually til it ran

out of gas - thought there was more in it. - put some in it, and it fired right off. What I did do was loosen up the

gas cap. It was on pretty tight. I had seen you mention about that, but never heard of over tightning a gas cap

would cause a engine to stall out. But,  I noticed on my lawn mower there is a hole in the top of the cap and not one

one the snowblower. When I go back home I'm going to start it againg and see what happens. I'm going to take off

the bowl, and see if there is any dirt in the bottom of it. By the way, I did purchase a repair manual for it when

I started to have the problems.  According to my serial # I have a 644E model. With the illistrations,

I believe it has series 3-4 carb on it. Do you think I should pull the gas tank off and blow it out and also the line to the

carb to make there is no dirt in either of them??

Thanks bud for all the feedback!!!

Bud