1984 MTD suddenly stopped working

Reply

  #1  
Old 04-17-06, 12:44 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
1984 MTD suddenly stopped working

I recently bought this old mower that ran perfectly for about a month. Today I got it out and it started right up. I drove it around for a while and shut it off. I then tried to start it again, but it would not. I checked to see if the engine was flooded; it was not. It also gets a good spark.
As the engine turns over I can see light smoke coming out of the muffler.
If I turn the choke on while trying to start it, I here this muffled "pop" sort of sound coming from around the carb and with the air filter off, white smoke comes out.

I have checked the oil, gas, and air filter.

When this happened, I had just had it running a few minutes ago. Any help would be appreciated.
 
Sponsored Links
  #2  
Old 04-17-06, 02:46 PM
puey61's Avatar
Member
Join Date: Apr 2004
Location: Upstate New York
Posts: 3,224
We need more information...engine model, type and code numbers please. Initially it sounds as though you may have a valve clearance issue but post back with the numbers first. Also, answer these - What color was the smoke from the muffler, blue or black? How exactly did you determine the engine is not flooding? Are the cooling fins under the blower shroud clear of debris?
 
  #3  
Old 04-17-06, 04:35 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
Hi, the engine is a 12 hp tecumseh. there are these numbers on the frame: 137-642-135/3z459. I think it is the model number.

I checked to see if it was flooded by taking out the spark plug and turning the engine over a few times.
The smoke coming from the muffler appeared to be white although I don't see it anymore.
The cooling fins look okay.

Additionaly, there is a strong smell of gasoline when I try to start it. It also looks like there is some gas leaking from under the air filter.
 
  #4  
Old 04-17-06, 09:07 PM
v8driver's Avatar
Member
Join Date: Sep 2005
Posts: 767
If you smell gas, its either leaking or overflowing... leaking from a gasket or overflowing from a stuck float or inlet needle.
 
  #5  
Old 04-21-06, 09:13 AM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
I just changed the oil (it had gas in it), changed the fuel filter, and checked the carburetor bowl, inlet needle. It all looked fine.
It still doesn't start.
Is it possible that the head gasket is blown?
Also, I'm wondering how the needle screw on the bottom of the carburetor bowl is supposed to be adjusted.
 

Last edited by msidan; 04-21-06 at 09:43 AM.
  #6  
Old 04-21-06, 10:59 AM
v8driver's Avatar
Member
Join Date: Sep 2005
Posts: 767
So the float wasn't hung up? Make sure the gas is cut off, then I'd look up that hole the inlet needle goes and make sure the inlet needle seat is still seated..., also the screw on the bottom of the carb is 1.5 turns out from all the way in snug as a baseline..... then fine tune when warmed up.
 
  #7  
Old 04-22-06, 12:19 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,639
Sure sounds like it's flooded to me. Leaking needle and seat?
 
  #8  
Old 04-22-06, 06:32 AM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
.[/QUOTE]
I checked to see if it was flooded by taking out the spark plug and turning the engine over a few times.[/QUOTE]

Was this the right way to see if it was flooded?

Underneath the engine on the mower frame is quite a mess of oily gas. It looks to be under the head gasket. Does this mean the head gasket is blown?
 
  #9  
Old 04-22-06, 11:57 AM
v8driver's Avatar
Member
Join Date: Sep 2005
Posts: 767
Yes.... but if the breather tube is low enough, the gas will go through that right into the oil. It sounds like the head gasket may be leaky or the head not on tight enough by the leaking gas under it.... Usually if the float is hanging up, or not adjusted right or inlet needle fell off or seat fell out or they aren't seating good.... with the fuel turned on the carb will overflow... into the oil and through the combustion chamber (if the intake valves closed it'll take longer) and out the exhaust.
 
  #10  
Old 04-22-06, 12:14 PM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,639
If there was gas in the oil, the engine is flooding. This will also cause the poppiing/huffing when trying to start, and the nasty oily mess you've described. The carb is flooding.

Usually an engine will still run with a blown head gasket. I don't think that's your problem.
 
  #11  
Old 04-22-06, 06:04 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
This probably sounds stupid, but how do I un-flood the engine? I thought I could just take the sparkplug out and the excess gas would come out when the engine is turned over.

As for checking the carburetor, its been raining here and I haven't gotten a chance to look at it yet.

Is the carburetor bowl supposed to be filled with gas?
 
  #12  
Old 04-22-06, 07:20 PM
v8driver's Avatar
Member
Join Date: Sep 2005
Posts: 767
Yes you can take the plug out, turn the engine over to blow out the fuel, and dry the plug and reinstall it.... BUT smell the oil, if it smells like gas, DO NOT RUN the engine till you change the oil. Yes gas is supposed to be in the fuel bowl... thats what a fuel bowl does is hold the fuel, the float operates a inlet needle up and down that lets fuel in, and the float should push that inlet needle up, shutting the fuel flow off so not to overflow... and when the fuel gets lower and lower.... the float does as well, letting more fuel in till it gets pushed back up and shuts the fuel off to the bowl.... it does this constantly. A stuck float or inlet needle, or leaky inlet needle or inlet needle seat will not control that fuel, letting it overflow.
 
  #13  
Old 04-23-06, 08:34 AM
hopkinsr2's Avatar
Member
Join Date: Feb 2005
Location: canada
Posts: 1,561
If you're sure the needle & seat are O.K, Remove the float & shake it & listen for gas sloshing around inside of it. Sounds like the float has sunk
 
  #14  
Old 04-24-06, 03:39 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
The needle and float move freely and I did not hear any gas in the float.

The engine won't even start with starting fluid; it just back-fires through the carburetor again.
 
  #15  
Old 04-25-06, 01:05 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
Thanks for all your sugestions, but I have to recognize my own limitations and I have taken the mower to my local MTD repair place. I will let you know how it turns out.
 
  #16  
Old 04-26-06, 02:23 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
I talked to the repair guy today and he said my mower would need a valve job and a new starter which together he said would cost $250-$350.

Anyone want to buy an old mower that needs some work? (ha ha)
 
  #17  
Old 04-27-06, 01:57 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,639
The thing that's not jiving here is that you started it right up at the beginning of all this.

Smell your oil in the engine. Does it smell like gas?
 
  #18  
Old 04-27-06, 03:58 AM
JLOpower's Avatar
Member
Join Date: Dec 2005
Posts: 106
Sounds like the repair man wants to send his kids to collage. Why would it all of a sudden need a starter? And engines don't run fine one minute and then need a valve job the next, unless something physically broke in the valvetrain. Valves, guides and seals all deteriorate slowly, decreasing performance and consuming oil at an increasing rate. They don't just reach a point where things stop working in that time frame. And if the valvetrain is broken, how did he diagnose the starter?

Here is what I think could be possible. You were using the machine and shut it off. The carb float or needle malfunctioned allowing fuel to enter the cylinder and eventually the crankcase. This would contaminate the oil and possibly could cause damage if the engine was run. But damage probably would not occur if you were just cranking the motor over with the starter motor. If the fuel contaminated the oil, you should be able to set things right by rebuilding the carb and changing the oil. If your engine has internal damage, your problems may have started before you realized it. If your engine was flooded before you ran it at the beginning of your posting, you may have done damage at that point.

If repairs would be that much, I suggest finding a different mower. You could also gather a bunch of friends together on a weekend and dig in to the problem and see if you can find the real situation. Just don't turn your back on the repair man when you pick up your mower.
 
  #19  
Old 04-27-06, 12:28 PM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
The oil does not smell like gas (maby very slightly from before I changed the oil) and the oil level doesn't seem to have risen at all.

I'm starting to think that it does not need a valve job and the repair man is trying to take me for a ride. I talked to the guy I bought this mower from and he said it just had a valve job when he got it. He said I could take it to him for him to diagnose so I will let you know how THAT goes in a week.

Maby the guy who did the valve job screwed up somehow.(forgot a gasket somewhere?)

As for the starter, it seems to work just fine except that it sticks sometimes.(keeps spinning after I turn the key off)
I had posted about this before and someone (I think it was Cheese) suggested that it was the starter solenoid.

Also, the guy who had this mower before me had left it outside under a tarp all winter with gas and oil in it. I don't know if that would make any difference.

Also, would starting it a certain way affect it? (always starting it at full throttle for example)
 

Last edited by msidan; 04-27-06 at 04:35 PM.
  #20  
Old 05-01-06, 05:52 AM
msidan's Avatar
Member
Thread Starter
Join Date: Apr 2006
Location: Gouverneur
Posts: 289
success!

Just took my mower to another repairman. He re-built the carburetor, and took the starter apart and greased it for. There was a peice in the starter that had come apart.(This liitle gear thing that turns the flywheel had a little worm gear thing inside it that came off, thus keeping the gear from popping back down when I start it). But anyway, it runs now!.

Oh, the float in the carb bowl is full of gas and was sinking.
I think I can trust this repairman, he did all this work for a very reasonable price.
 
  #21  
Old 05-02-06, 01:53 AM
cheese's Avatar
Forum Topic Moderator
Join Date: Jul 2001
Location: USA
Posts: 16,639
Yep, it was flooding. Anyway, glad you got it fixed and thanks for the update.
 
Reply

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Thread Tools
Search this Thread
Display Modes
'