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.

 

[Ilikeurtractor]

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.

I certainly can't say the same for mine but it is the smaller of the two engines but I still think it should be a fair amount stronger than it is. In the higher gears (4th, 5th, 6th) when I get it rolling at lower rpm, opening the throttle wide only makes smoke and it takes a few seconds to get up to speed with virtually no feel of acceleration. Climbing a slight hill in any of these gears and I have to be careful of stalling out especially below 3/4 throttle.

I guess I'll be looking at a rebuild in the near future. Looks like engine kits are nice and expensive (I question whether it's worth it at this point). Anybody know of any "deals" for parts out there?

 

[Kernopelli]

Just a thought...One thing you can't rule out, at this point anyway is that you may have valve/head issues and not ring or cylinder wear issues. Probably wouldn't be a "major" expense in comparison if it's only a matter of having the head gone through.

 

[Ilikeurtractor]

Good point. Looks like I can get a head gasket relatively cheap all things considered. Would it be unusual if the cam was rounded off?

 

[Kernopelli]

Good point. Looks like I can get a head gasket relatively cheap all things considered. Would it be unusual if the cam was rounded off?

Hmmm, don't know. Always a possibility I guess. I have heard of this a number of times with gas engines but I would say not as likely as

1. Worn rings and/or cylinder wear

2.Head/valve issues

In the event that it is ring/cylinder wear...Your engine doesn't sound like it's gone too far south...just possibly needs to be freshened up. I'm just throwing this out there and someone more knowledgeable will have to comment on it. I have no idea if this can be done with a diesel but don't know why not. I had a 2 cyl gas engine that had low compression. The bore was a little egg shaped but still within spec for stock pistons, the rings were shot. I lightly used a Sunnen AN-112 hone to get the cylinder back round and flex hone to finish w/ fresh crosshatch. I bought 10 thousandth over rings and put them on the stock pistons and filed them down for correct end gap. Probably could have gotten away w/ stock rings but I was right at the outer limits of stock bore spec. Engine ran like a top for several years right up to the day I sold it.

Now I was lucky enough to have the hone set and my friend owns a Yamaha dealership and loaned me a flexhone to crosshatch the bore. You may not even have to go that far. If things aren't too bad and it's just a ring issue.... just put a fresh face on the cyl walls with a flex hone, some new rings and you're back in business? Who knows, I'm kind of thinking out loud and throwing ideas/possibilities out there. Bottom line is, it's still too early to tell exactly what you are looking at.

 

[Ilikeurtractor]

Yeah, I've been contemplating what the "minimum" I could get away with if it is only the rings. I don't have a lot of experience with re-ring jobs but I wonder what putting in a new cross-hatch would do with existing rings? I've even heard of people reusing head gaskets and it worked. I'm not sure I want to be that sloppy or take the chances associated with it but it seems like a set of rings alone are gonna set me back a few hundred bucks just in parts. Might be better off saving up for another used tractor now that I've gained some experience in what to look for engine-wise. Then again, I hate thinking about this one getting neglected. Everything else seems to be fine on it. Kind of a shame. I could just live with it, but come-on it's a tractor for crying out loud. It should be able to pull it's own weight with ease!

 

[Ilikeurtractor]

I rechecked the compression today. I just cranked the engine until the gauge wouldn't climb anymore. I also did it with the engine cold. The front cylinder gave 390 psig and the rear 340 psig. They took roughly a dozen cranks but I didn't specifically count them. I didn't squirt any oil in the cylinder because I wasn't sure how much and also I only had the glow plugs out and I'm not sure if it would work putting the oil through those holes.

I'm surprised to see the 390 reading - I wouldn't think that would even be possible at my elevation given the "new" value of 455 psig. Apparently the 3.5%/1000' of elevation power loss doesn't directly relate to compression although I would have thought it would. The pressure here is about 11.6 psia and so I would think it's like losing 3 psi of boost vs. sea level. For a 20:1 compression ratio, for example, the difference in pressure readings would be 294 psia vs. 232 psia from purely a compression standpoint which ignores the pressure gained due to the heat of compression. I haven't tried to go down the road of calculating the theoretical pressure value due to heat of compression + compression ratio at my elevation and even if I tried I'm not sure if it would be meaningful let alone correct. I don't know the compression ratio for the engine anyway.

For the next step I'm going to pop of the valve cover and redo the valve clearance just to be sure it's in spec. I'll also check the push rods and make sure they aren't bent. IMHO I'm still thinking the problem should be something obvious and major and not just general engine wear given the symptoms.

 

[Kernopelli]

The compression sounds better. I am not sure how altitude affects compression. I was always under the assumption that the "thin air", power loss issue was due do less concentrations of oxygen, not necessarily the amount of total "air" (gases) available? I would guess that barometric pressure could effect things also though....I don't know. I live in S. Illinois where the tallest points are the tops of the corn stalks in Sept. :thumbsup: The affects of altitude don't come up in conversation very often.

I suggest you give Bill Rogers at Valley Power a call. I think he knows as much as anyone about these engines and can give you some sound advice. I read a post he made stating that 350 psig could dramatically affect the KE70's performance. You are only averaging 15psig above that across the two cylinders so I have a feeling that is the issue but I am sure they can point you in the right direction and maybe save some time and effort.

 

[Ilikeurtractor]

Thanks, I'll keep that in mind.

 

[Ilikeurtractor]

The compression sounds better. I am not sure how altitude affects compression. I was always under the assumption that the "thin air", power loss issue was due do less concentrations of oxygen, not necessarily the amount of total "air" (gases) available?

My understanding is that at less ambient air pressure, less oxygen is available by weight for the same amount of volume (basically what you stated above). So with less oxygen available, then you have less available fuel that can be burned and henced lower available power. The actual compression pressure (ratio stays the same of course) is also affected as in my previous post but the major hit one takes is the lack of amount of oxygen. I've read were a turbocharger is desirable in high elevations because the turbo will actually spin faster in lower pressure environments under the same conditions, somewhat compensating better than a supercharger and raising the effective amount of air (oxygen) to the engine. A turbo would be a neat project, but I'd be happy just to get back to OEM performance

 

[Kernopelli]

Turbos are cool and there have been several TBN members that have retrofitted their tractors. If I remember correctly, one Yanmar owner did specifically because of altitude related performance.

I too think that you would probably be well pleased just to have the stock performance...to go from barely pulling itself to spinning tires would make a guy feel like he was in tall cotton. I think you have a solid tractor that is very well built...just needs a little freshening. I don't know what you have invested in it but I suspect that whatever it is, at this point an additional $300-$500 put into it wouldn't be a deal breaker on it.(?)