MF 135 Perkins Gas 3 Cylinder Backfiring no Power

[slhilbert]

I hadn't started my MF 135 Perkins Gas 3 Cylinder for several months. A few weeks ago I started it up and it was backfiring really bad, popping all over the place. I was able to rev the engine at that time, so I revved it up and after a few minutes the pops and backfires stopped and I was able to start mowing down the fields with my rotary cutter. I mowed for probably 1.5 hours without an issue.

The next day I got back on the tractor to continue to mow and it started right up and backfired for maybe 30 seconds and then was fine. I mowed for about 15 minutes and all of a sudden the tractor died. I tried starting the tractor and it was backfiring all over the place again and I couldn't get it to rev at all. Eventually it got so bad, I couldn't even get the tractor to start anymore.

I took the carb off and thoroughly cleaned everything, put it back on today and I can start the tractor and it will idle for a while, but if you try to rev the engine (give it gas) it backfires all over the place. At this point I can't even get the tractor to move as it dies if you try to put it in gear.

I currently have the mixture screw all the way out, which will let it idle.

I am pretty much at a lost and no really a great mechanic, so what are my options at this point? Part of me wants to go buy a new carb and see if I can just call it a day, but at $400 that isn't a cheap option.

Here are a few videos that show the issues.

Thanks for the help!
Stuart

 

[big bubba]

what grade gas do you use? assuming non ethanol? fuel treated as well? surely you've learned by now to use non ethanol in old tractor & small engines. empty tank & purge the system w/good fuel

actually didn't realize the MF135 came with gas model, thought it was only 3cyl Perkins diesel
welcome to the world where diesel & gas ain't what they used to be
& use a good gas stabilizer once it's running smooth... you have a great vintage model. had MFTO35 for 28 yrs on this end. glad yours still operates, best regards

 

[Egon]

Check timing & govenor?

 

[big bubba]

plugs, pts, ign wires as well. though feel it could well be fuel quality related if the machine was running fine months ago, good luck

 

[seville009]

Check your airbox/filter in case rodents chewed up your filter and the pieces ended up getting sucked in.

 

[slhilbert]

Check your airbox/filter in case rodents chewed up your filter and the pieces ended up getting sucked in.

Air box is clean and actually off right now, so that isn't it.

 

[slhilbert]

Since the last post, I have completely disassembled the carb and cleaned it. Drained and replaced the fuel. Replaced the sediment bowl and put new fuel line and filter on.
That got me enough juice to get the tractor very slowly and with a lot of finesse into the garage. The tractor was starting up just fine and idling but still couldn't power it up without it backfiring out of the exhaust only now.

I pulled the distributor cap to check the points. Noticed some metal shavings. When I went to adjust the points I notice the distributor cam isn't turning, which I am pretty sure it needs to be and seems like in all the videos I look at it does. If I manually turn the distributor then I can get it to rotate a bit, but it doesn't continue to turn. This is foreign territory for me. Please advise.

See the two videos that show the issue.

Thanks Again!
Stuart

 

[ultrarunner]

I've had a bad condenser behave as you describe...

The cam must turn when cranking the engine.

I've never had a fuel issue related to backfire...

Either it was a spark issues or once a stuck valve...

 

[George2615]

Since the last post, I have completely disassembled the carb and cleaned it. Drained and replaced the fuel. Replaced the sediment bowl and put new fuel line and filter on.
That got me enough juice to get the tractor very slowly and with a lot of finesse into the garage. The tractor was starting up just fine and idling but still couldn't power it up without it backfiring out of the exhaust only now.

I pulled the distributor cap to check the points. Noticed some metal shavings. When I went to adjust the points I notice the distributor cam isn't turning, which I am pretty sure it needs to be and seems like in all the videos I look at it does. If I manually turn the distributor then I can get it to rotate a bit, but it doesn't continue to turn. This is foreign territory for me. Please advise.

See the two videos that show the issue.

Thanks Again!
Stuart

Yes, that distributor shaft must turn when the engine is cranking. If not, you won't get spark to each plug. I cannot see how it ran at all in your first post if the shaft doesn't turn. Seems like something is broken on the bottom of the distributor shaft. I had an MF135 many years ago but never had to remove the distributor. I'd say the drive gear is broken but you'll have to pull it to check.

 

[slhilbert]

I think me pulling the distributor cap must have been the straw that broke the camels back.

I pulled the distributor and you can clearly see that the gear is all chewed up.

I am assuming the distributor goes into the crankshaft, do I need to worry about the gears in there?

Thanks!
Stuart

 

[ultrarunner]

I don't know your engine but engines I work on the distributor meshes with the camshaft.

It looks like something foreign got between the two gears?

If luck is on your side the pieces dropped to the bottom of the pan and the gear on the cam is ok...

Worked on a lot of flatheads and found well worn but never broken dist drive gears.

 

[DJ54]

I'm like Ultrarunner, all I've worked on the distributor is driven off the camshaft. Shavings under the distributor cap would lead me to believe the rotor button was catching on something, but enough to shear the teeth on the distributor gear..??

Are those gears pot metal/aluminum designed to be the weak link in the system to prevent damage to the camshaft? Hopefully someone familiar with the engines will chime in here soon. I looked up the distributor through AGCO and it shows that gear held in place by a 1/4" X 11/16 pin. If it was catching that bad, I'd have thought it would have sheared the pin, or split the gear before stripping it.

Don't know if the link will go through to the page with the distributor :https://parts.agcocorp.com/us/en/apbsearch?q=masseyferguson/651199/l&name=135+TRACTOR# But looks like the gear is around $178.

***Link just opens as far as the 135 tractor itself. You'll have to drill down through the menu to find the Perkins gas engine, then on down to find the distributor.***

 

[big bubba]

OP: looks like you have the patience & tenacity to repair your engine. glad you found the culprit. good advice given here as well... suggestion once repaired: i highly recommend using only ethanol free fuel in your machine.
might be a good time to adjust the valves as well, regards

 

[ScipioUSA]

I think me pulling the distributor cap must have been the straw that broke the camels back.

I pulled the distributor and you can clearly see that the gear is all chewed up.

View attachment 831560

I am assuming the distributor goes into the crankshaft, do I need to worry about the gears in there?

Thanks!
Stuart

Well, I was going to respond to your first post that the backfiring probably had a little something to do with the timing, and looks like your further troubleshooting has confirmed it.

From your last video, it looks like there is some damage to the drive gear (the one in the engine). Is that just metal shavings from the damaged distributor gear? Or is it actually damage? It looks like the distributor is driven off a stub shaft that threads into the governor, so the good news is that you dont need to pull your camshaft out if the internal shaft is damaged.

At a bare minimum you need a new distributor gear, and you would want to pull that apart to see if you can rebuild it (or get it sent to be rebuilt). You might be able to find a rebuilt or new distributor that could mesh, assuming the gear still in the engine isnt completely damaged.

Remanufactured Distributor fits Massey Ferguson 135 150 521189M91 fits Delco Remy 1112457

Distributor for Massey Ferguson Tractor(s) 135, 150. Replaces Delco Remy Mfg Number(s) 1112457, Replaces Massey Ferguson OEM Number(s) 521189M91.

www.tractorpartsasap.com

The bigger thing is what got in between those gears to cause the problem in the first place?

While you troubleshoot, you might want to put something over that hole so that you dont accidentally knock dirt or other stuff down in there...

 

[slhilbert]

Well, I was going to respond to your first post that the backfiring probably had a little something to do with the timing, and looks like your further troubleshooting has confirmed it.

From your last video, it looks like there is some damage to the drive gear (the one in the engine). Is that just metal shavings from the damaged distributor gear? Or is it actually damage? It looks like the distributor is driven off a stub shaft that threads into the governor, so the good news is that you dont need to pull your camshaft out if the internal shaft is damaged.

At a bare minimum you need a new distributor gear, and you would want to pull that apart to see if you can rebuild it (or get it sent to be rebuilt). You might be able to find a rebuilt or new distributor that could mesh, assuming the gear still in the engine isnt completely damaged.

Remanufactured Distributor fits Massey Ferguson 135 150 521189M91 fits Delco Remy 1112457

Distributor for Massey Ferguson Tractor(s) 135, 150. Replaces Delco Remy Mfg Number(s) 1112457, Replaces Massey Ferguson OEM Number(s) 521189M91.

www.tractorpartsasap.com

The bigger thing is what got in between those gears to cause the problem in the first place?

While you troubleshoot, you might want to put something over that hole so that you dont accidentally knock dirt or other stuff down in there...

I found the part on Ebay and paid $125 for it, so way cheaper than the one linked thankfully. Not a lot of options online for it. Right now all the wholes are covered as I wait for the parts. I will see what it takes to dig into the engine more... I did read that the distributor gear needs to be inserted at precisely a certain position and I am wondering if it wasn't and that is the culprit.

Thanks!
Stuart

 

[slhilbert]

I'm like Ultrarunner, all I've worked on the distributor is driven off the camshaft. Shavings under the distributor cap would lead me to believe the rotor button was catching on something, but enough to shear the teeth on the distributor gear..??

Are those gears pot metal/aluminum designed to be the weak link in the system to prevent damage to the camshaft? Hopefully someone familiar with the engines will chime in here soon. I looked up the distributor through AGCO and it shows that gear held in place by a 1/4" X 11/16 pin. If it was catching that bad, I'd have thought it would have sheared the pin, or split the gear before stripping it.

Don't know if the link will go through to the page with the distributor :https://parts.agcocorp.com/us/en/apbsearch?q=masseyferguson/651199/l&name=135+TRACTOR# But looks like the gear is around $178.

***Link just opens as far as the 135 tractor itself. You'll have to drill down through the menu to find the Perkins gas engine, then on down to find the distributor.***

Thank you so much for the link to the parts... The diagrams alone on there worth their weight in gold. The Perkins 3 Cyl. Gas isn't so common from what I have found so being able to see all the diagrams is amazing!

I was able to find a new/old stock distributor on eBay for $125 so it has been ordered.

Thanks so much!

 

[ScipioUSA]

I found the part on Ebay and paid $125 for it, so way cheaper than the one linked thankfully. Not a lot of options online for it. Right now all the wholes are covered as I wait for the parts. I will see what it takes to dig into the engine more... I did read that the distributor gear needs to be inserted at precisely a certain position and I am wondering if it wasn't and that is the culprit.

Thanks!
Stuart

Glad you found one at a discount! You might want to make sure you have good points and a good condenser in it before you install it. I have the Blue Streak part numbers if you want them, since I have the Perkins Gas in my MF20. (I know your pain on finding info, this is not a super common engine it seems)

It would be unlikely that it would have moved positions on you if all of the bolts were tight. There is a thrust washer under the end cover (the little triangle cover that is near the distributor), so pulling that cover might show you if something had moved out of where it should be.

If you dont have one, might be worth getting the service and parts books from agcopubs . They arent too expensive, and save a lot of heartache. The parts you can see online from the link DJ54 sent you, but I also like a hard copy for looking at in the garage sometimes.

 

[George2615]

I found the part on Ebay and paid $125 for it, so way cheaper than the one linked thankfully. Not a lot of options online for it. Right now all the wholes are covered as I wait for the parts. I will see what it takes to dig into the engine more... I did read that the distributor gear needs to be inserted at precisely a certain position and I am wondering if it wasn't and that is the culprit.

Thanks!
Stuart

I'm sure at one time the dist. was installed correctly before the gear got chewed up. Before you install the new dist you will have to get the timing mark on the crankshaft damper pulley set to top dead center then install the dist. so it will be lined up to fire on number one cylinder. Once started you can fine tune the timing with a timing light.

 

[DJ54]

Thank you so much for the link to the parts... The diagrams alone on there worth their weight in gold. The Perkins 3 Cyl. Gas isn't so common from what I have found so being able to see all the diagrams is amazing!

I was able to find a new/old stock distributor on eBay for $125 so it has been ordered.

Thanks so much!

You're welcome. Many may not know most of the major equipment companies even know these parts pages are out there. Now that you know, feel free to pass this info on to others.

You'll find that using the OEM part number is the best way to search for a specific part and get the correct one.

 

[DJ54]

I'm sure at one time the dist. was installed correctly before the gear got chewed up. Before you install the new dist you will have to get the timing mark on the crankshaft damper pulley set to top dead center then install the dist. so it will be lined up to fire on number one cylinder. Once started you can fine tune the timing with a timing light.

TDC on the compression stroke.