MF 135 Continental gas- losing power

[nashvegas]

I've got a '68 (or maybe '67) MF 135 with a Continental 4 cylinder gas engine. Starts great, but after the engine warms up after 10 or 15 minutes, I lose power and it stalls/cuts out. I can re-start after full choke, but it cuts out again when I accelerate. Especially noticable with the PTO engaged finishing mower. Prior to it cutting out, the engine temp always operated in the normal range, never over heated. Any advice would be appreciated.

I inherited this iron maiden from my Dad about 20 years ago and up until this past April (bought a New Holland T1510), I used it to mow about 5 acres, pull an occasional stump and plow/disc a small garden plot. My grand pa bought the MF new back in the 60's. I have the original owners manual, plow, disc and blade. I've taken good care of it with routine maintenance, always stored in the barn, etc. I am ready to do a complete body and engine restore once I get motivated.

My plugs look good, haven't checked points and distributor yet although I am guessing I will need to rebuild the engine due to power loss- it's never been re-built to my knowledge. I'll post some pics soon. Any advice would be appreciated.

 

[sweettractors]

I suppose you have already checked intake air flow? What kinda oil pressure is it running? Ken Sweet

 

[nashvegas]

I checked the intake and the air is flowing good, clean filter. I'll need to buy me an oil pressure gauge and diagnose. In the meantime, I'll change the oil and filter and see if this helps.

 

[sweettractors]

My mechanic said check the carburetor function and also check for a leaky intake manifold gasket. Ken Sweet

 

[nashvegas]

Thanks a bunch Ken. I replaced the intake and exhaust manifold gaskets 2 years ago and they appear solid and tight, no leaks there. I'll give the carburetor a good cleaning and see if this helps.

 

[sweettractors]

I just thought of something else, The Fuel coming from the tank could be restricted around the tanks outlet or in the settling bulb area. Ken Sweet

 

[Mike476]

Checking for fuel first (take the line off at the carb) is a good idea. If there is fuel but your not sure if it is enough flow take a look at the screen filter at the top of the glass bowl, mine has been fairly restricted with debris in the past.

 

[Mike476]

Was wondering if you have had a chance to find your problem, might be something I have to deal with myself some day with my 135 continental.

 

[nashvegas]

Thanks for all the advice. I've been out of town for the past week and traveling - I'll post an update once I get back into town later this month. I've got a bunch of stumps to pull out so I've got to get working on a fix quickly.

BTW, if anyone needs replacement blades for their finishing mower- check out www.mowpart.com...bought a set of 3 blades for my Befco "72 deck for less than $65.00

 

[slhilbert]

I have had a problem similar to this. After checking the tractor over I noticed that one of the plug wires was pulled from the distributor cap. Might have been doing some extreme bush hogging. I put it back in, but the problem persisted. In the end the replacing of the distributor cap solved the problem. I am not technical enough to understand why that solved the problem, but it did.

Stuart

 

[slhilbert]

Further note. This happened again to me and I took off the distributor cap and put it back on and that resolved the issue.

Stuart

 

[The kid]

This sounds like a fuel problem. Make sure cap is venting. Next time it quits loosen cap to see if under slight pressure. I bought a new vented cap, but the vent release under pressure is greater than it should be. I wedged. Small piece of plastic to assure the vent is open under the cap.

With engine cool. Take the. Fuel line loose from the carb to see if there is a decent flow from the tank. If not clean the sediment bowl or replace it to improve fuel flow.

Check for debris inside tank. If old gas has been in the tank with an additive stabilizer then some varnish could be built. Up at the cutoff inside the tank.

Check to see if your running an external fuel filter that might be close to the heat shield or manifold. Is fuel boiling in the sediment bowl?

Check for debris in front of your radiator. Check water flow inside the radiator when warm. Could have clogged radiator or bad thermostat.

Could have a bad coil breaking down once it gets hot. Just like an old car. Lots of things give similar symtoms.

 

[slhilbert]

I believe this is the carb I need, can anyone confirm?
Massey Ferguson Carburetor - New for Massey Ferguson 135 (12994)

 

[slhilbert]

This sounds like a fuel problem. Make sure cap is venting. Next time it quits loosen cap to see if under slight pressure. I bought a new vented cap, but the vent release under pressure is greater than it should be. I wedged. Small piece of plastic to assure the vent is open under the cap.

With engine cool. Take the. Fuel line loose from the carb to see if there is a decent flow from the tank. If not clean the sediment bowl or replace it to improve fuel flow.

Check for debris inside tank. If old gas has been in the tank with an additive stabilizer then some varnish could be built. Up at the cutoff inside the tank.

Check to see if your running an external fuel filter that might be close to the heat shield or manifold. Is fuel boiling in the sediment bowl?

Check for debris in front of your radiator. Check water flow inside the radiator when warm. Could have clogged radiator or bad thermostat.

Could have a bad coil breaking down once it gets hot. Just like an old car. Lots of things give similar symtoms.

1. I have checked for the fuel cap venting issue and it seems like it is fine.
2. The tank did have some sediment in it, but not a lot and I have cleaned it out.
3. No external fuel filter
4. Gas isn't boiling
5. Replaced sediment bowl
6. Fuel line is clear.
7. Radiator is clean
8. Radiator isn't leaking

After carb rebuild if I continue to have issues, I will look into the thermostat.

Stuart

 

[BobG_in_VA]

I believe this is the carb I need, can anyone confirm?
Massey Ferguson Carburetor - New for Massey Ferguson 135 (12994)

BZZZZZ! Wrong carb...If I'm not mistaken you said at the start of the thread that you had the Cont. 4 cyl. gas...the carb you identified here is for the 3 cyl Perkins gas engine...you should be looking for a Marv. Scheb. TSX882 if you have the Z145 engine....BobG in VA

 

[slhilbert]

BZZZZZ! Wrong carb...If I'm not mistaken you said at the start of the thread that you had the Cont. 4 cyl. gas...the carb you identified here is for the 3 cyl Perkins gas engine...you should be looking for a Marv. Scheb. TSX882 if you have the Z145 engine....BobG in VA

HA HA HA! I have a 3 cylinder perkins so maybe I am on the right track after all!

Thanks,
Stuart

 

[SIMassey]

HA HA HA! I have a 3 cylinder perkins so maybe I am on the right track after all!

Thanks,
Stuart

This is the confusion caused by highjacking a thread.