Gravy
Platinum Member
I will be really interested to see how the Kohler fits if you go that way. One of these days I will have to replace my Robin, and I'd like to have an alternate choice.
PT422 Engine shaking / sputtering
- Thread starter KMA
- Start date
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Vacuous_One
New member
Well...if anyone cares, I've put the Robin Subaru FI injected engine (EH72) in my PT422.
The old engine just quit on the wife one day while she was mowing and wouldn't start again. Pulled it and played around with it awhile, but finally just got tired of it. Never liked that Robin engine...wouldn't start when moderately cool...like so many others have stated!
So, I looked for possible replacements and finally settled on another Robin engine. (Wasn't hoping for that because of all the hassles it gave me, but went with it due to the cost and lesser modifications needed to fit it in the tractor.) Also, I really wanted fuel injection. Never have had a lot of luck with carburetors, either. The only change I ended up having to make was to slot the engine mounting holes in the tub as I needed to shift the new engine to one side about a 1/4" for additional clearance to fit it best.
After running it for a bit now, I have to say we're quite satisfied. The bloody thing even starts easily now! And, it's much smoother running than that older, smaller engine.
I can't say we've noticed anything terribly different regarding operation...i.e., the HP difference isn't really evident...although, it might have helped when mowing and trying to go up some of the banks around the place. It's hard to judge though, might just be wishful thinking, although I really think it's helped at least a bit. Seems to go up the hills easier with the mower running whereas the older engine really required a big slowdown in forward motion!
Now that winter's here, we'll see how it really does, though! I'll try and post observations as the weather gets a bit colder.
The old engine just quit on the wife one day while she was mowing and wouldn't start again. Pulled it and played around with it awhile, but finally just got tired of it. Never liked that Robin engine...wouldn't start when moderately cool...like so many others have stated!
So, I looked for possible replacements and finally settled on another Robin engine. (Wasn't hoping for that because of all the hassles it gave me, but went with it due to the cost and lesser modifications needed to fit it in the tractor.) Also, I really wanted fuel injection. Never have had a lot of luck with carburetors, either. The only change I ended up having to make was to slot the engine mounting holes in the tub as I needed to shift the new engine to one side about a 1/4" for additional clearance to fit it best.
After running it for a bit now, I have to say we're quite satisfied. The bloody thing even starts easily now! And, it's much smoother running than that older, smaller engine.
I can't say we've noticed anything terribly different regarding operation...i.e., the HP difference isn't really evident...although, it might have helped when mowing and trying to go up some of the banks around the place. It's hard to judge though, might just be wishful thinking, although I really think it's helped at least a bit. Seems to go up the hills easier with the mower running whereas the older engine really required a big slowdown in forward motion!
Now that winter's here, we'll see how it really does, though! I'll try and post observations as the weather gets a bit colder.
Gravy
Platinum Member
I care!
Thanks for the info. Cold starting has been the Number 1 issue with my Robin engine. Please update with how it starts in sub-freezing temperatures. If it starts without help at 20*F or lower I might have to start looking for one.
Thanks for the info. Cold starting has been the Number 1 issue with my Robin engine. Please update with how it starts in sub-freezing temperatures. If it starts without help at 20*F or lower I might have to start looking for one.
Marks481
Platinum Member
- Joined
- May 29, 2005
- Messages
- 978
- Tractor
- Power Trac 422 (2005)
Details, please! Engine model and number. Shaft size? Did you need a new spider coupling to mount the pumps? Does your PT have all the pumps mounted on one side of your engine, or all on the same side? Muffler arrangement? Where did you buy it?
Pictures, please. If you look in the archives, debates of replacement engnes are one of the more popular topics.
Stories like this make me want to upgrade my PT, but (hopefully) my engine still has years and years of life. As much as I would like to emulate Tim Taylor and soup up my tractor...
I would love to have a few more hp... My 22 hp robin engne feels weak, starts to bog down when the grass gets tall when I am cutting.
Pictures, please. If you look in the archives, debates of replacement engnes are one of the more popular topics.
Stories like this make me want to upgrade my PT, but (hopefully) my engine still has years and years of life. As much as I would like to emulate Tim Taylor and soup up my tractor...
I would love to have a few more hp... My 22 hp robin engne feels weak, starts to bog down when the grass gets tall when I am cutting.
Vacuous_One
New member
26°F out...PT stored in unheated metal building...sitting unused for ~ 1 month...standard oil as from the factory...throttle at 1/2, crank for 5-10 seconds & started. No problem! :thumbsup:
After using for ~1 hour, left sit outside for ~2 hours...throttle at 1/2, crank for 2 seconds & started. :thumbsup:
The old engine wouldn't have started in the first place without multiple attempts, ether, or jumper cables. Heck, it wouldn't even do that at 50°F, let alone 26! :laughing:
Pic's attached: Overall views, engine, some details, etc.
As stated previously, had to slot the motor mounting holes to shift the engine to the right to provide clearance...see the spark plug wire on the "...Tub Clearance.jpg" photo曜ust enough room to keep it out of the way of the hood.
Also, (forgot) that I had to add a return line to the gas tank to accomodate the fuel injection. Again, pretty easy thing to do. Bought grommet and angle fitting for the hose connection, drilled hole for the grommet in the plastic tank, installed grommet and fitting, installed hose, done.
The oil dipstick just touches the muffler flange slightly, but not enough to worry about. (That's the engine muffler from the EH65 engine that was installed originally from the factory.) I'll get around to taking care of that when I've got time or an urge to do it.
Finally, I like the oil filter location/angle...it's slanted down and to the back. This makes it easier to remove and install. The old oil filter location (and the existing hydraulic filter) were my two biggest pet peeves about the layout of this machine. They just weren't/aren't user-friendly.
The engine cost $1944 and I paid $150 total freight. While a lot more than I could have spent getting the old engine fixed and more than I would have liked to have paid, I'd still do it again. In a minute. It's that much better with this engine. Time will tell as far as longevity/trouble, but for now we're quite happy. The machine's finally reliable and usable when the temperature drops below 50°!
I don't know how the latest carbureted Robin engines are, but I'd never buy another one. I'd negotiate with P/T to pay the difference and upgrade to the fuel injected engine on any new machine!
In any case, that's my humble opinion after all I've gone through...other opinions may vary...
After using for ~1 hour, left sit outside for ~2 hours...throttle at 1/2, crank for 2 seconds & started. :thumbsup:
The old engine wouldn't have started in the first place without multiple attempts, ether, or jumper cables. Heck, it wouldn't even do that at 50°F, let alone 26! :laughing:
Pic's attached: Overall views, engine, some details, etc.
As stated previously, had to slot the motor mounting holes to shift the engine to the right to provide clearance...see the spark plug wire on the "...Tub Clearance.jpg" photo曜ust enough room to keep it out of the way of the hood.
Also, (forgot) that I had to add a return line to the gas tank to accomodate the fuel injection. Again, pretty easy thing to do. Bought grommet and angle fitting for the hose connection, drilled hole for the grommet in the plastic tank, installed grommet and fitting, installed hose, done.
The oil dipstick just touches the muffler flange slightly, but not enough to worry about. (That's the engine muffler from the EH65 engine that was installed originally from the factory.) I'll get around to taking care of that when I've got time or an urge to do it.
Finally, I like the oil filter location/angle...it's slanted down and to the back. This makes it easier to remove and install. The old oil filter location (and the existing hydraulic filter) were my two biggest pet peeves about the layout of this machine. They just weren't/aren't user-friendly.
The engine cost $1944 and I paid $150 total freight. While a lot more than I could have spent getting the old engine fixed and more than I would have liked to have paid, I'd still do it again. In a minute. It's that much better with this engine. Time will tell as far as longevity/trouble, but for now we're quite happy. The machine's finally reliable and usable when the temperature drops below 50°!
I don't know how the latest carbureted Robin engines are, but I'd never buy another one. I'd negotiate with P/T to pay the difference and upgrade to the fuel injected engine on any new machine!
In any case, that's my humble opinion after all I've gone through...other opinions may vary...
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Vacuous_One
New member
Tim, I hear you...I've added my answers to your questions in blue in your quoted statement. (At least, I hope I did...hope it comes out the way I think it will when it makes it up on the site! If not, I'll give it another try...
Thanks so much for posting this information! :thumbsup:
Your feedback definitely makes me feel more comfortable in choosing the EH72 FI as a replacement. I was so concerned about cold whether starting, I planned on buying a Kohler. But there's no denying it would be much, much easier to drop in another Robin engine. Based on your feedback, I'm pretty sure that is the route I'm going to go now. I've been traveling overseas quite a bit lately and have had no time to work on my tractor. I have some vacation time coming up after Xmas and will try to get started on the replacement then.
Only issue (albeit minor) is that the shaft on my EH65 is 1 7/16 vs 1 1/8 on the EH72 FI. I'd have to get a different coupler setup.
Thanks again!
Vacuous_One
New member
KMA, glad to be of some help. Good luck on your upgrade!
J_J
Super Star Member
- Joined
- Sep 6, 2003
- Messages
- 18,952
- Location
- JACKSONVILLE, FL
- Tractor
- Power-Trac 1445, KUBOTA B-9200HST
Well, I guess you could really call your updated PT, a 428, since the HP is the last 2 numbers in the model number.
