Engine start/run issues

[Rich Gilbert 1]

I recently (July '14)  bought a 1986 308-8.  This tractor usually runs just fine but has begun to shut off unexpectedly and then not want to restart.  This has happened several times, I just put it away, and then the next day all seems good for about 15 minutes, then the same thing happens all over again. 

It appears to be very rich in mixture because when trying to restart the motor, it coughs black smoke several time but never actually restarts.  There is fuel spitting out of the carb when I run the engine and I am thinking maybe the carb has a stuck float in the float bowl???

I have never had one of these apart and hate to tear into it but must do something.  Maybe some carb cleaner???

 

I really like this tractor, we had an older one (not sure which model) when I was a kid in the '60's and it ran for many years.

[SousaKerry 503]

I would wager that it is your coil or condenser.  When they start to fail they will drop out when hot, easy to test warm it up until it fails and then check for spark .  I would use a spare spark plug so you don't have to mess with the hot engine and fuel issues.

[Rich Gilbert 1]

Thanks for that.  Today it would not even start, just one black belch from the exhaust.  I will check the spark next.

[WH nut 553]

Also don't forget the make sure the exhaust isn't plugged.

[Rich Gilbert 1]

Well, I checked the spark and it appears to be OK so I took the carb off, cleaned it (the float was not stuck), reinstalled the carb and the tractor still will not start on gasoline.  Used some spray ether and the engine runs until the ether runs out and then will not continue to run or restart on gasoline (it is fresh gas).  It was no longer spitting fuel out the front of the carb so that is a slight improvement but still not running.  The fuel filter is almost new and flows fine.  Not sure what is next....maybe a new spark plug although this one looks fine.

[boovuc 1,090]

Hi Rich,

 

There are a few things you should check now that you have determined you have consistent spark. First would be to make sure your fuel pump is delivering fuel. Disconnect the fuel line from the carb and while holding the end of the hose into a metal bucket and away from any ignition sources, crank the engine and observe how much fuel it spurts. It "should" spurt quite a bit. If all you have is a dribble, you have a fuel delivery issue. (Bad pump, bad lines or a plug in the line or at the bottom of the fuel tank).

If you have good fuel pressure, then you have a plugged up carb. Check the inlet to the carb then carefully screw in the main jet counting rotations until it "gently" seats then screw the needle all the way out and look for deposits and spray Seafoam or a carb cleaner through the orifice and screw it back in until it seats again. Next just screw it back out to the number of turns you counted earlier. (1.5 to 2 rotations normally on a K series).

 

If it continues to act up, you probably should take the whole carb off and disassemble it and soack it in a carb cleaner. If it runs on either, you have a fuel issue ether in the delivery or in the carb.

[Rich Gilbert 1]

OK, I will try those but not today.  "Other" priorities by the ball & chain.

[boovuc 1,090]

Rich..how did you make out or still no time to get into that carb?

[Rich Gilbert 1]

Interestingly enough, when I tried to start it today it ran just fine but withou the air cleaner so I mowed part of the lawn until it cut dowm a nearly brand new mower deck belt.  I have a spare 8411 belt but it is about 2 or 3 inched too long.  I guess a call to the supplier tomorrow is in order.  This spare belt came in a WH bag and is marked as a 8411 belt although it was made in Mexico.

 

One challenge at a time.

 

Thanks to all for you're help and ideas.

[WH nut 553]

^{Please don't cut grass without the air filter. You wouldn't believe how much garbage the motor will suck in. Fix the problem first. If it wont run without the filter I would make sure the mounting screws aren't too long or tight binding something in the Carb.}

[Rich Gilbert 1]

Here is the belt with a small rubber band to hold it close to the pulley.  I do not think the idler pulley can make up all of that slack!  Waiting for an answer from the supplier.

And, I will not mow any further with out the air cleaner on the engine.  Thanks for your help.

 

How do I attach a picture to this?

[KATO 115]

On the bottom right of the post window you will see a box that says "more reply options"

click on that and scroll down, at the bottom you will see a box that says "attach files".

when you click it ,it will open up an explorer window where you can select files from your

computer

[Rich Gilbert 1]

Here is the picture:  OOPS too big.

 

Cannot make it smaller...operator ignorance.

 

 

 

[KATO 115]

If you have Microsoft Office on your computer you can right click the picture and select "OPEN WITH"

then choose "Microsoft Office".It will open in a window ...on the top tool bar is an "EDIT PICTURE"

button. Click that and you will see  options on the right side.Click "RESIZE". I prefer to use the percentage settings

as opposed to pixels. After you have set it to the desired size click OK then close it and it will ask if you want to save changes

say yes of course and presto... your done. If you dont have office ,there are lots of free photo editing programs out there.

[Rich Gilbert 1]

OK, here is the photo.

 

Thanks to all.  The mower now runs OK but I still need a correct belt.

Edited August 12, 2014 by Rich Gilbert

[Rich Gilbert 1]

And here is the tractor.

[km3h 543]

Are you sure that you have installed the belt properly? Usually the slack is taken up by an idler pulley. Did you remove the deck before attempting to install the belt? You may not have the belt routed around the pulleys correctly.

[Rich Gilbert 1]

Yes, that picture is with the belt around all of the pulleys including the idler pulley.  I did not remove the deck since I have to take the Mule belt off anyways and I can reach all of the pulleys and route the belt around all of them properly.  Is the 8411 belt the proper one?  The bag says it is 77' long but it is about 82".

 

This is a 36" RD deck.  I had one 8411 that was the correct size but the belt was hitting one of the bolts and broke in about 40 minutes of mowing.  My fault entirely.  This belt came from the same supplier in a bag clearly marked correctly as an 8411 (as is the belt) but it is obviously too long.  I am reluctant to order another belt from the same supplier again but I really need to mow the lawn soon.

 

Any recommendation on suppliers?

[gwest_ca-(File Mod) 11,510]

8411 is 1/2" x 77" and the correct spindle belt.

102741 is 1/2" x 96.6" and the correct drive belt.

 

Operator manual

 

Illustrated parts list

 

Garry

[Rich Gilbert 1]

Garry,

 

Thanks for those manuals.

 

Rich

[Rich Gilbert 1]

Update:

 

My belt supplier took back the "long" belt and gave me a correct one.  Yeah!!!!

Put on the correct belt and it only ran abour 30  minutes, shut off and would not restart.  So now I will look at the coil and condenser and replace them.

 

One issue at a time.

[km3h 543]

Could be that the fuel tank cap is clogged up. When it stops next time remove the cap and then try to start it.

[Rich Gilbert 1]

I will try that tomorrow.

Thanks

[Rich Gilbert 1]

The fuel cap is not the problem.

 

It will run about 30 to 40 minutes and then it starts to run rough with some missing, then it runs worse until it finally stops running altogether.  I have tried all throttle positions when this happens and even checked the choke to make sure it is not closing.  When it finally stops, it will not restart for about 2 hours.  Then it will only run for about 15 to 20 minutes and repeats the whole thing again.   When this happens, the exhaust is very black, obviously running very rich with fuel pouring out the front of the carb.

 

I tried opening the air mixture screw a half turn but that did not improve the situation.  Carb tuning is not my strong point so I am not sure what is next.  I just want to mow the grass!, in something less than 2 days of this start and stop stuff.

 

I did get the belt situation resolved so thanks to all for your ideas and help.

[km3h 543]

After it stops running and you then try to restart, pull the plug and see if it is wet. It could be that it floods and after two hours the plug is dry and the engine will restart. Someone correct me if I am wrong but I believe you should turn the needle in to reduce the flow of gas, not out. It is not air you are regulating but fuel.