PT 422 hard to start

[BobRip]

It sounded real sick to me. Don't forget to leave a section hanging out to remove it when you are done.

Well the cord worked fine. I ended up using about 3 feet of 550 paranoid. It did take two people to put the valve retaining clips back on. It still is not starting, so I ordered a new carb. Any other ideas would be appreciated. I also got some no ethanol unleaded gas.

 

[MossRoad]

Paracord, perhaps? :laughing:

Glad it worked for you on the valves. Bummer that it won't start yet.

 

[BobRip]

Today I put on the new carburetor. I got it started but for the first start I had to disable the spark on one cylinder and then once it started I reconnected that spark plug wire. I have now started it about 10 times and while it did backfire a little through the carb, it started. I now am guessing that one of the coils is doing something strange and have ordered a new coil. The engine runs kinda of rough at idle. My guess is that the automatic spark advance on the bad coil is stuck on advance. At least I can use it again. I borrowed my neighbors mower with a Kohler engine and it started great. I talked to Terry at Power Trac today and they have PT with Kohler engines. They still have some left with Robin engines.

 

[MossRoad]

So the future for now is new Kohlers from PT?

 

[Marks481]

So the future for now is new Kohlers from PT?

That would be good news. Very few people in this forum seem satisfied with the Robin engines.

 

[BobRip]

I think the Kohler is a really good choice for PT. It removes the weakest link in their smaller tractors. Terry says that they start much better.

 

[BobRip]

I ran a test today and disabled one spark plug at a time. It ran worse on the side I suspect is a problem.

 

[BobRip]

Bob, you should have done that earlier.

 

[MossRoad]

Bob, you should have done that earlier.

Hahahaha Nice! :thumbsup:

 

[MuncyBob]

I didn't have the coin to drop a Kohler in last year or would have done so instead of a valve job on the Robin.

 

[BobRip]

I am getting ready to cut the engine shroud where the air comes into the engine cooling fan. I am not sure of the best place to cut it. Any suggestions? I have seen a picture of one cut, but can't remember where.

 

[BobRip]

I got it fixed. Praise all who helped. I replaced the ignition coil on one side. The other side had been replaced a few years back. The bad coil tested ok with the spark gap tester. Let me summarize.
The machine is a Power Trac 422 model year 2000 with about 1100 hours on it.
Symptoms:
1. Hard to start and got worse over several months.
2. Backfire through the carburetor when cranking.
3. Started on one plug and not the other. Did not backfire on the good plug only.
4. Ran rough and stalled at idle.
5. Ran better while running on one plug on one side than the other side. It had an occasional miss on the bad coil. This was what triggered the coil replacement.
Fix: Replaced bad coil and started cold on first crank using choke. Now starts at idle with no choke once it has run a little.

My thanks to Terry of Power Trac and Steve of the parts department at Continental Engines. And of course to my friends here at Tractorbynet.

 

[BobRip]

I went into the garage this morning, turned the key and it started. At idle and no choke. I mowed for about an hour and it climbed slopes that it would not before. I mowed through 1 ft high grass with no problems. I wonder how long that coil was acting up. It's like a different machine.

 

[cqaigy2]

That's great news! Thanks for posting everything in here for the rest of us.

 

[BobRip]

I am curious if anyone has seen a similar failure.

 

[ponytug]

Bob,

Thanks for sharing! Great story.

All the best,

Peter

 

[BobRip]

On the engine shroud cutting: I cut it horizontally at the centerline of the drive shaft. I was able to remove both halfs after doing this. I used a Dremel tool to do the cutting. Not the cleanest cut but it only took about 10 minutes. I took all of the bolts on the shroud out and pulled it away from the engine to keep from damaging engine parts. It might not have been a problem, but wanted to make sure.

 

[BobRip]

Be sure to inspect the cooling fins on the engine cylinders and the oil pump cooler which is at the base of the oil filter. Mine had a lot of junk on them. I doubt if this stuff extends engine life. It will now be much easier to clean the fins, just take the top of the shroud off.

 

[cqaigy2]

I'd completely forgotten about cutting plastic shroud when last pulled my engine. I had a lot of dry grassy material kind of packed up around everything, and i agree that can't be particularly good for the engine, especially on a hot mowing day.

 

[BobRip]

I have cleaned the area before, but some of fins were completely blocks with oil plus whatever. It is not easy to get to. Cutting the shroud made it a lot easier and a better cleaning job. I will still have to pull the gas tank and then the gas tank support bracket to access it.