KE70 engine low power?

[Ilikeurtractor]

It has become apparent that the KE70 engine in my Iseki TX1300F seems to not be running correctly. Anybody have any experience with these engines and how much power they seem to have? They are suppose to be equivalent to the K3A engine and mine just seems to be a dog. I take about a 20% hit on power due to my elevation - 6200' asl but this seems to be much more loss than that. The engine seems to puff a lot of white/gray smoke under acceleration and load. Even just in neutral, going from low idle to full throttle it seems to bog down and take some time to get to full rpms. Here's what I have done/learned so far (not necessarily in the order completed):

1.) Drained fuel, new fuel filter & fuel. Checked air filter and even ran it shortly w/o the filter installed just to see any differece - none noted.
2.) Played with IP timing - the engine had two 1/32" gaskets installed under the pump since evidently previous owners lost the metal shims. I removed one of them and the white smoke and miss went away at full throttle which it originally had. Still gray/white smoke and lack of power under load and seems like it's not entirely timing related. Not sure where I'm at as far as degree BTDC because I don't have the skill/tools to check it but I've had every thing from no gaskets (wouldn't start) to a 1/64" (didn't seem to run much better but starts fine), the 1/32" (starts fine but still no power and gray/white smoke), and the 1/32"+1/64" gaskets installed (starts a little harder but pretty much the same low power and smoke).
3.) Fuel pump rebuilt and new injector nozzles. This helped some - less white smoke and easier to start, but it wasn't the culprit (and wasn't worth the money for the gain) - same low power
4.) Checked to make sure the cam gear timing marks were lined up with the crankshaft gear timing mark - they were
5.) Did a compression check - cylinder closest to radiator was 310 psig and the other was 295 psig. The gage was still climbing on both cylinders but the instructions that came with the tester said not to crank more than 8 revolutions for each pressure check. Not exactly sure why. The service manual states the compression should be 455 psig @ 2800 rpm and I have no idea what rpm the starter turns the engine but I doubt it's 2800 rpm. I also did the check with the engine up to operating temperature.
6.) Checked cold valve clearance - all were factory spec. (0.014" if memory serves me).

I haven't noticed any usage of coolant and the oil level has been holding over the past 10 or so hours of use so I don't think I have a blown head gasket or am burning oil. The previous owner stated he never added any fluids during the last 10 years of his use. The white/gray smoke smells like diesel fumes as best as I can tell. Unloaded/idling at any rpm, I can only see a faint amount of white smoke and sometimes none at all.

So I'm guessing it probably needs a ring job to get that compression back up, but I would hate to go through the expense and time of rings and bearings only to get what I already have (like with the pump and injector nozzles). I don't think I'll ever see 455 psig at my elevation anyway, maybe more like 370 or so at best. When I removed the valve cover vent, it seemed like very little crankcase gases were coming out but I really don't have anything to compare it to. Am I missing any other obvious checks? I find it hard to believe this engine is as weak as mine feels from the factory. Any comments are appreciated.

 

[BillS2009]

Have you checked the air cleaner?

 

[Ilikeurtractor]

Have you checked the air cleaner?

Yes, I actually removed the filter element for a short period of time just to see if it would make any difference and didn't notice any.

At this point, I'm really just wondering if anybody who has one of these engines in their tractor have noticed that they may seem to lack power vs. other tractor engines of similar power. I know there aren't a lot out there to compare to but I'm wondering why Mitsubishi went from this style to the K3 series engines. I was talking to a guy who runs Iseki's under the Bolens brand of the same time era, and he stated he would stay away from the 2 cylinder engines because of lack of power. However, the service manuals rate the 2 cylinder engines at about the same power as the 3 cylinder engines. I don't know if the torque curves are similar or not though and maybe there is a significant difference in that area. Also, I'm not sure how the flywheels compare between the two types of engines. Maybe the two cylinder engines have a more massive flywheel and this causes lag in acceleration.

 

[Kernopelli]

I don't think comparing the KE70 to the K3A is a good comparison. The K3A has considerably more displacement (669 vs. 776cc). I know Iseki/Bolens used the K3A in tractors rated at 17 HP, Mitsubishi used it in their tractors as well and rated it at about the same HP.
I also think you have answered your own question. I think the problem sounds like low compression. I'm not sure why the manual would suggest test compression at 2800 rpm. I think you are testing the compression correctly. I would not be too concerned about the 2800 rpm issue. Looking online, I see that the KE70 is supposed to have 455psig. Bill Rogers at Valley Power ( definitely one of the most well versed Mitsubishi/Satoh guys around) states in one of the forums that when the K3A falls below 350psig it will definitely show starting and power issues. This would also explain the smoke. One thing you can do is pour a little oil in the cylinder and see if your compression increases noticeably. If it does, I think you can pretty well bet on bad rings/ cylinder wear.

 

[Ilikeurtractor]

I don't think comparing the KE70 to the K3A is a good comparison. The K3A has considerably more displacement (669 vs. 776cc). I know Iseki/Bolens used the K3A in tractors rated at 17 HP, Mitsubishi used it in their tractors as well and rated it at about the same HP.
I also think you have answered your own question. I think the problem sounds like low compression. I'm not sure why the manual would suggest test compression at 2800 rpm. I think you are testing the compression correctly. I would not be too concerned about the 2800 rpm issue. Looking online, I see that the KE70 is supposed to have 455psig. Bill Rogers at Valley Power ( definitely one of the most well versed Mitsubishi/Satoh guys around) states in one of the forums that when the K3A falls below 350psig it will definitely show starting and power issues. This would also explain the smoke. One thing you can do is pour a little oil in the cylinder and see if your compression increases noticeably. If it does, I think you can pretty well bet on bad rings/ cylinder wear.

Thanks, I'll try the oil test and report back when I get some results probably over the weekend. Also, I always wondered why the Bolens tractors had claims of higher horsepower for the same engine in comparison to the service manual statements. I have the horsepower curves in a service manual for the K3A and K3B engines and they are rated at around 13 "PS" and 15.5 "PS" respectively. The first problem I had with it was I didn't know what a "PS" was. According to wikipedia a "PS" is a DIN unit and equivalent to 735 watts which is less than the accepted horsepower rating of 746 watts. So the engines are, in reality, more like 12.8 hp and 15.2 hp (I realize we are splitting hairs here and also I don't have exact numbers in front of me so forgive my memory if they are off). I would have to go by the service manual curves before anything else. I see ads claiming upwards of 22 hp for the K3B engine in Bolens tractors and unless that is some later revision I would find it hard to believe it is that high. I understand your statement on the displacements being greater on the 3 cyl. engines and I agree that should have a significant affect on ratings although it is not apparent from the official literature which is really strange. My two cylinder also is much louder and "rappy" sounding than the K3B engine I listened to. Not sure why they sound so much different since they both use the swirl chamber design but I guess the engines may not have much in common beyond that.

 

[Kernopelli]

My two cylinder also is much louder and "rappy" sounding than the K3B engine I listened to. Not sure why they sound so much different since they both use the swirl chamber design but I guess the engines may not have much in common beyond that.

All the 2 cylinder engines have that "knock". They are not as smooth as 3 cylinder engines but they tend to produce more torque compared to equal displacement 3 cylinder engines.

Edit; One thing you have to remember is some HP ratings on these tractors is taken at the PTO and some are rated at the engine. The K3B was also used in the CIH 234/235 and rated at 15.2 PTO hp and (I think) about 18 engine HP, it is also larger displacement yet with 849cc. 22hp might have been attainable with some injection pump tuning?

 

[Ilikeurtractor]

Edit; One thing you have to remember is some HP ratings on these tractors is taken at the PTO and some are rated at the engine. The K3B was also used in the CIH 234/235 and rated at 15.2 PTO hp and (I think) about 18 engine HP, it is also larger displacement yet with 849cc. 22hp might have been attainable with some injection pump tuning?

So that may explain why Iseki's TX1300 is 13 hp (assumed to be @ the PTO) and Bolen's G15x is 15 hp (assumed to be @ the engine) with the KE70 (and K3A?). Neat marketing stuff I guess...

 

[wrenchturner]

My Satoh Beaver with the KE70 engine had plenty of power. I could use a finish mower in above knee high grass with no problem at all. Elevation is about 800 feet. If my Satoh Beaver was a real beaver it could chew through a 6 inch dogwood in sixty seconds.

 

[Ilikeurtractor]

My Satoh Beaver with the KE70 engine had plenty of power. I could use a finish mower in above knee high grass with no problem at all. Elevation is about 800 feet. If my Satoh Beaver was a real beaver it could chew through a 6 inch dogwood in sixty seconds.

What size finish mower?

 

[suntreemcanic]

I am at only 3800 feet elevation, my two cylinder TX1500F Iseki has lots of power and good low end torque. It has much more power than traction. I have no way of loading it except pushing the front end loader into a pile of dirt and it will spin all four wheels quit easily. Oh and it makes black smoke in abundance when it is accelerating the engine or pulling hard in high gear up a hill. It reminds me of the old diesel trucks of the 60s. Mine uses no oil. I do not know if this is any comparison for your tractor. I am really impressed with how had it pulls at low RPM it reminds me of the old 2 cylinder John Deers, they will lug down to nothing and still want to pull.