Time for a New Engine?

[atwood]

I apologize, it has been a long time since I posted anything. In 2005 I bought a PT 425 after reviewing the many great posts here on the Tractorbynet, Power Trac forum. Overall I like the machine and its capabilities and diversity. It has some a few weak points though.

The main one in my opinion is the Robin engine. I know this has been posted before especially by Gravy. After using it only for 275 hours my complaints are these:

1. Very, very difficult to start in cold temperatures. I don't have a heated garage, etc. I've tried battery chargers, different spark plugs, magnetic heaters, space heaters, etc. Somedays I get lucky, most of the time it's a PITA.

2. Too LOUD! I know the muffler is designed by PT, but darn does it have to be so noisy?

3. Uses fuel like crazy.

So I've talked to Terry on numerous occasions and the latest conversation was about possibly replacing the engine with a Kohler CH-730(25 HP) or possibly CH26 (26 hp, Fuel Injected). He said the engine would run me about $1800 and if PT did the install an additional $350-$400 for labor. He did say the muffler might be a problem, no further details were described.

I also asked about the 1430. Perhaps I should of coughed up the bucks for this model 5 years ago. Bigger, stronger, etc. Sometimes the 425 seems a little light duty for the task, especially FEL, excavating, grading work. I think more mass is a good thing for this kind of work. Terry informs me that the Duetz, while better starting than the Robin in cold weather, is not great. Also it is just as loud with a different tone of course.

So is the new Kohler the answer and worth the money or should I look for a CUT or look at Ventrac with a turbo diesel? Any suggestions, experience is very much appreciated.

Thanks!

 

[American Bulldog]

Well, I just got my first PT, and I also own a Ventrac. The Ventrac is a great mower, but that is it. It climbs hills better, it is more comfortable, and it is quieter. I have the 31 HP Vanguard engine, which is a really nice little 3 cylinder. I saw the FEL for it, and it sucks. The motor is up front, so the weight distribution is all off for something like that. The cab attachment is amazing, and it has a nice snowblower as well. For pretty much everything except loader work, the Ventrac beats the Power Trac. For loader work, Power Trac is amazing. The Ventrac hydraulics are much more noisy than the Power Trac, but they do work.

I don't really have enough knowledge to give advice on changing your motor, but I would have to say that I am impressed with the Deutz diesels. I have the 1460, and the motor is very nice; it starts up better than my Deere, and it runs smooth. I would bet that the 1430 is a really nice unit. It has been my experience that diesels can be really bad in the cold as well. It is not so much the motor, but the fuel. If you are not careful, it can gel, get frozen moisture in it, etc..... I don't care what motor you have, none will run on bad fuel. Usually with a temperamental gas engine, a little starting fluid will do the trick in the winter. If the starting fluid doesn't work, that means that you have no spark. If you are losing spark, usually that means that you are not running the engine long enough, and it is fouling the plugs.

Let us know how you make out.

 

[SpringHollow]

Diesels are notorious for being hard to start cold. Having said that, these deutz engines start better cold than any I have seen so far. I have started at 20 °F with no glow plugs, no heaters. It looked ugly for a bit but it started. I subsequently installed glow plugs which really help the starts.

Gelling is fairly easy to prevent if you treat your fuel.

Ken

 

[American Bulldog]

Diesels are notorious for being hard to start cold. Having said that, these deutz engines start better cold than any I have seen so far. I have started at 20 ｰF with no glow plugs, no heaters. It looked ugly for a bit but it started. I subsequently installed glow plugs which really help the starts.

Gelling is fairly easy to prevent if you treat your fuel.

Ken

My Deere 5520 has an intake heater, and it will pretty much start at any temperature. I have started it as low as -10 degF. However, it got some water in the tank about 4 years ago, and it literally took two years before everything went back to normal. We drained the tank 3 times, the fuel bowl separator countless times, and put gallons of anti gel and water stabilizer. When you get the really cold temps, it can really cause problems with diesel. Just the few little droplets that were remaining in the tank would freeze and clog up the fuel lines. A real PITA!!! Anyways, it is all fixed now.

Where I live, 20 degF is not cold at all. That is an average winter morning.

 

[SpringHollow]

20 °F is warm for an average winter morning here. My point was that it was starting without an intake heater at 20 °F, something my other CUTS (Ford, MF, etc) would not do. They had trouble above freezing if one did not use the glow plugs. I got my tractor late in the winter and that was the coldest I had to start it. I then added the glow plugs which made it start MUCH easier. I do not know how cold mine will start with the glow plugs that i installed since it has been inside my shop since then.

Ken

 

[BobRip]

The trouble here is not so much the engine, but the fact that a starter which was sized to turnover the engine also has to rotate the pumps. There are four pumps and lots of cold hydraulic fluid that has to be circulated. If you put a different engine in it it might not help.
For the cost of an engine, could you build an insulated shed with some heat in it? This might sound extreme, but a small shed would be about the same as the engine. Put some electric heat in it, or even use a block heater on the hydraulic tank and that heat will also heat the building. Just a thought here. What do other's think?

The Kohler fuel injected engine is supposed to be a great engine. I would talk to the manufacturer about this application. Maybe it will start with low cranking speeds, which is what happens with the extra load of the pumps.

Oh, my Robin 22HP engine has about 900 hours on it and is doing fine, but my garage rarely gets below 60 since it is supper insulated and attached to the house. I did have trouble with cold starting when the PT was parked in the shed.

 

[MossRoad]

I apologize, it has been a long time since I posted anything. In 2005 I bought a PT 425 after reviewing the many great posts here on the Tractorbynet, Power Trac forum. Overall I like the machine and its capabilities and diversity. It has some a few weak points though.

The main one in my opinion is the Robin engine. I know this has been posted before especially by Gravy. After using it only for 275 hours my complaints are these:

1. Very, very difficult to start in cold temperatures. I don't have a heated garage, etc. I've tried battery chargers, different spark plugs, magnetic heaters, space heaters, etc. Somedays I get lucky, most of the time it's a PITA.

2. Too LOUD! I know the muffler is designed by PT, but darn does it have to be so noisy?

3. Uses fuel like crazy.

So I've talked to Terry on numerous occasions and the latest conversation was about possibly replacing the engine with a Kohler CH-730(25 HP) or possibly CH26 (26 hp, Fuel Injected). He said the engine would run me about $1800 and if PT did the install an additional $350-$400 for labor. He did say the muffler might be a problem, no further details were described.

I also asked about the 1430. Perhaps I should of coughed up the bucks for this model 5 years ago. Bigger, stronger, etc. Sometimes the 425 seems a little light duty for the task, especially FEL, excavating, grading work. I think more mass is a good thing for this kind of work. Terry informs me that the Duetz, while better starting than the Robin in cold weather, is not great. Also it is just as loud with a different tone of course.

So is the new Kohler the answer and worth the money or should I look for a CUT or look at Ventrac with a turbo diesel? Any suggestions, experience is very much appreciated.

Thanks!

Did you try replacing the coils? I thought that was the solution for cold starting.

If it was me, I would:
Change the plugs to one step hotter than the factory plugs.
Change the ignition coils.
Clean the carb and adjust properly.
Clean the air filter.
Put the biggest battery with the most Cold Cranking Amps you can find in it.
Keep it on a charger at all times in the winter.
Always give it a two second shot of starting fluid before the first attempt to start in cold weather.
Try a jumper pack to boost CCA in the winter.
If all that fails, then I would consider switching engines or selling outright.

The price they quoted you to do the labor for swapping the engine seems very reasonable, by the way.

 

[KMA]

If you are thinking about a new engine, could you shoe horn in one of these?

Kohler Aegis LH690

http://www.kohlerengines.com/onlinecatalog/productDetail.htm?productNumber=Aegis LH690

 

[MossRoad]

Probably not, my guess.

 

[MuncyBob]

It seems the days that I need my PT in the winter are colder than other days!!.......what I do is fire up the kerosene heater and place it near the engine/tank. I take precautions to avoid unexpected happenings!! This seems to help a lot and I have yet to have a "no start" winter day.

 

[ClintBlake]

I have also struggled with the cold starting and many of the other problems with the Robin engine. My PT422 stays in an unheated shed. In the winter, I put two mangnetic heaters under the hydraulic tank and leave them on (for atleast 24hrs) if I think there is any chance I may need the tractor. Between that and using a battery charger on engine start mode, I have been able to start it. If it is really cold (teens or below), I will also throw a couple of moving blankets over the tractor to help hold in the heat.

My tractor has about 700hrs on it and I have literally had to put the engine back together several times. When the Robin finally gives up, I am going to look seriously at the Kawasaki and Kohler engines to replace it, even if it means significant modifications.

I love the little tractor, but the Robin engine and limited wheel torque have always been problem.

 

[atwood]

Thanks to all of you for your insights. In a perfect world it would be nice to be a able to put a 3 cylinder diesel into the 425. Unfortunately even the 1430's diesel (2 cly) is loud and according to Terry cannot be fitted with glow plugs. I've tried most of MossRoads suggestions but I like the jumper pack idea , beats pulling the truck up for a jump. Perhaps a bigger CCA battery and I'll look into changing the coil. BobRip's practical common sense advice is also noted. The Kohler engine suggested does look sweet. I passed the Ventrac dealer today on the way home and I really don't think it would be the answer. Although I'm sure the B&S diesel is a nice power plant. Any ideas on how to quiet down the 425 with the Robin engine?

 

[Bob999]

Unfortunately even the 1430's diesel (2 cly) is loud and according to Terry cannot be fitted with glow plugs.

While the Duetz diesels don't have the capability to be fitted with flow plugs it is my understanding that Duetz does offer intake air heaters which are an alternative approach to cold weather starting used on many diesels.

 

[Marks481]

1. Replace the muffler. Find a decent glass pack.I replaced the stock mufler with a supertrapp muffler with the 6" resonator. it made the sound deeper, but I don't think it changed the dB much. My recommendation: find a different muffler.

2. Install sound insulation or just neoprene rubber underneath the ROPS. the ROPS reflects the noise and makes the tractor seem a lot louder then it is.

Model 5S Mufflers

3. mount sound insulation on the inside of the front of the engine canopy. It is about the only spot any would fit; anything that stops the noise from bouncing around has gotta help.

 

[BobRip]

2. Install sound insulation or just neoprene rubber underneath the ROPS. the ROPS reflects the noise and makes the tractor seem a lot louder then it is.

I noticed on a friends 422 without the ROPS that his machine was much quieter than my identical 422 (same engine, same model year, same muffler). I have added some foam under the ROPS. I can't tell you how much change it made, but I think it's a good idea. I also wear ear protection with a radio. This helps a lot and is a good idea for any machine like this.

 

[American Bulldog]

I noticed on a friends 422 without the ROPS that his machine was much quieter than my identical 422 (same engine, same model year, same muffler). I have added some foam under the ROPS. I can't tell you how much change it made, but I think it's a good idea. I also wear ear protection with a radio. This helps a lot and is a good idea for any machine like this.

That makes a whole lot of sense. The plate steel on the roof surely will reflect the sound. Never even thought about that. Good call on the foam.

 

[horticattleman]

I have a 425 with a Kohler form the factory. I changed the engine at 1200 hrs and even though I really really really dont like Kohler, I chose the replacement engine because it would have been sooooo much trouble to re-route all of PT cables, etc. I think the Honda 24-26 hp line is great also.

 

[SpringHollow]

Deutz calls them glow plugs (they do glow) but they are air intake heaters. I really like them.

Picture of mine glowing here:
USA Discount Generators - Standby and Portable Gillette Generators

 

[MossRoad]

Very nice.