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Re: 3608 serial BEN00484

Just a thought you may want to make sure that the waste gate isn't stuck shut, verify your desired air pressure versus your actual air pressure. If actual is significantly higher than desired then you're getting too much boost making you lean with cold cylinders and low fcf. Not trying to steer you in the wrong direction just offering a suggestion
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Re: 3608 serial BEN00484

Thanks for your help!

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Re: 3608 serial BEN00484

Here are some more comments.

You should be sure about the site altitude so that you can calibrate the pressure module as accurately as you can.  This is important for the best engine performance.  500 ft. is a pressure of 14.49 psi.  So if you have it set at 14.6, you should reset it.  But you should really determine the correct site uncorrected barometric pressure.

If the fuel out of the dehy is really 967, then a config setting of 910 is not close enough, in my experience.  A setting of 910 would make the afr rich and this could be what is causing the engine performace issue, that the afr is too rich.  You should make sure that the fuel really is 967 or whatever it is and reset the config values (bru and specific gravity) to the new numbers.  This should allow the engine to start and run better.  Then after the engine warms up, you should be able to apply load and when the operating temperatures are stable, you retune the engine (PC CAL with an exhaust analyzer).  This should get you back to running well.  A 0,5 g NOx engine has a target ppm NOx of 50 ppm for tuning purposes.

This sounds like your most immediate problem right now.

If you start it in PC CAL, you will still have to have the btu and sg at the right numbers in order for the engine to run well.

 

Best Regards,

Al Hunt

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Re: 3608 serial BEN00484

Yes I did leave a few things out. Unit is in a plant and the fuel comes from dehy. It was shut down for about 3 weeks so we could run 2 3516's to perform state emissions testing,which are still running. Altitude is around 500ft 14.2. I have ran it in pc cal and none of the cylinder temps will get up to around 700 degrees. Had an analyzer hooked to it and it was showing real lean. Change the btu's for more fuel and it gets worse. FCF goes up and so does load. All the signs of it being overloaded are there and it is not. Except fuel command and it stays around 48%. BTU is 967 on site and unit is set at 910.

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Re: 3608 serial BEN00484

Here are a few comments on your situation.

You mention that you calibrated the new pressure module to 14.6 psi.  I assume that this is the site uncorrected barometric pressure.  You don't state what the site altitude is but it is important that the pressure module is calibrated to site value.

You didn't state how the engine shut down or whether it was running and stopped or had been down a long time.  Either way, there is the possibility that the fuel has changed (at least temporarily).  That is what the event code is telling you; the btu of the fuel right now that the engine is getting has a lower btu than what is in the configuration screen and what the engine was tuned to.  It is possible that work has been done on the wells that furnish the fuel and that nitrogen has been introduced into the fuel supply of the engine.  We have seen that occur before.  So I would suggest that you obtain a current fuel analysis and determine the btu and the specific gravity of the current fuel.  A fuel analysis will confirm a change and if this is so, it most likely is a temporary condition.

Have you tried starting/loading the engine in PC CAL?  This might allow the engine to run and pickup the load, allowing you to determine more about why the engine has performance issues.

The engine may also have misfires that aren't sufficient to trigger the misfire fault code but is sufficient to affect engine power.  What spark plug are you using?  The current spark plug Cat recommends for this engine is 479-7702.  This part number replaces the 301-6663, which didn't really give the performance reliability that Cat desired.  The correct spark plug gap setting is 0.011" for the G3600.

 

Maybe these comments will point you in the right direction.  We can respond to other questions that you may have.

 

Best Regards,

Al Hunt

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3608 serial BEN00484

I have a 3608 that was shut down and upon start up it would not start. Air pressure was reading 62.5psi. It was diagnosed a faulty air/fuel module(gold brick). It had the old style box one and we recieved a new gold brick and had to install new mounting plate. Since it was installed and the air pressure was calibrated to 14.6 it will start and run but not carry a load. It is going down on E885(3) low fuel correction factor. Unit is showing a load at idle of 70-100%. Is there anything else that needs to be done when changing the old style to new style gold brick?

 

Thanks