Help with Kohler engine

[Shane T]

I typically do all my own service work but the Kohler Ageis has EFI and there is only so much you can do without the right software and training. The authorized service shop I have used in the past has shown little interest in working on my carpet cleaning equipment. If I can't find someone I will be junking this unit.
What started as an intermittent problem with the engine loosing power has become a problem all the time. I think the problem is in the electronics somewhere.

 

[Dolly Llama]

can you be more specific, Shane?


..L.T.A.

 

[Cleanworks]

Before looking at the electronics, make sure you've checked the obvious things like fuel pressure on both the in and return lines, fuel filter, air cleaner, etc.

 

[clean image]

What error codes are you getting if any ?


I have one with 2800 hours I started having intermittent problems. Started changing parts with a new unit I had. Come to find out it was fuel filter. Should have 2 of them

 

[Acp]

I have a very good Kohler mechanic. Hes got access to the software etc. Very easy motors to work on.

If you can shoot a short video of the power loss and send it to me I will show him

is it a power loss that drops RPMs way down and sounds like the engine is chugging? or does it completely shut down?

do you know if this model has hydraulic lifters?

 

[Jim Williams]

I know this is obvious but did you try new spark plugs? I had my old machine to bog down one time and it was just a spark plug.

 

[Shane T]

Well, this has been a long time problem that would show up on the job causing me to come back to the shop and get my back up unit. Then when I returned at the end of the job I would start it back to check it out and could not get it to repeat the problem. It might be weeks before it would happen again. Now I can't use it at all. The unit has about 4100 hours.
Basically as I put more load on the engine(ie. the longer the wand it on the carpet) the slower the engine runs till it will actually stall.

I have done the following:
checked compression and leak down test on both cylinders
checked engine air filter
checked engine exhaust
changed spark plugs, coil packs
changed fuel filters(2), pump, pressure regulator, injectors
checked vacuum plumbing and filters as well as the silencer. I have even ran the unit with the recovery tank disconnected and then without the silencer just to make sure there was not restrictions.

No error codes that I am aware of. The light on the front of the machine is not on.
Yes it has hydralic lifters which have been changed in the past because they were very loud.

I'll try to get a video of what it is doing.

 

[Acp]

sounds exactly like what was happening to me when hydraulic lifter was sticking.

would lose power and rpm, eventually stall... happening very rarely at first then more often, could never recreate the problem.

seemed like fuel starvation kind of.

replaced all the lifters, push rods and did head gasket, crank case seal while I was at it. Runs like a brand new motor now

 

[Shane T]

Bjorn, how many hour on your engine?

 

[Acp]

4000+ but it runs on propane so usually 30% or so more life than running on gas

 

[clean image]

Need to check to see if any codes stored

If the light is the MIL light, then turn the key on and off 3 times and then turn on and watch the MIL light.

You will get a code even if there is no codes. I think it 62 without looking at manual

It will block fast, count the first set. Followed by pause. Then count the second set

If mil light not hooked up, first thing you need to do... you have 31 right?

 

[Shane T]

Need to check to see if any codes stored

If the light is the MIL light, then turn the key on and off 3 times and then turn on and watch the MIL light.

You will get a code even if there is no codes. I think it 62 without looking at manual

It will block fast, count the first set. Followed by pause. Then count the second set

If mil light not hooked up, first thing you need to do... you have 31 right?

Checked this morning, no stored trouble codes.
Found broken wire to oil pressure sending unit, repaired and it runs some better for the moment. I will have to play with it more to know for sure.
Found that the crankcase has about 1-2 psi pressure when there should be about that much of vacuum instead. Will pull apart the breather tomorrow and check it out.

 

[Acp]

@Shane T forgot to mention we did also the breather gasket as it had failed and I remember my guy saying that is very common on these command pros