waukesh 7044 gas engine for compression is rpm hunting issue

[synchro]

Did you replace the ignition module IPMD also?

 

[ATSman]

hi ,
which form i need to discuss?

Another forum for engines you can google SMOKSTAK.COM

 

[prajeesh thomas]

Yes we replaced.

 

[GoldDigger]

If the engine has a low oil pressure or oil level switch that drives an ignition or fuel cutoff that might be opening intermittently, either because of actual low oil level or a faulty switch.

 

[prajeesh thomas]

We replaced the oil pressure sensor & harness,same result

 

[rambojoe]

Check the mechanical governor...and as mentioned, if there is a intake leak, then the gov. could be just hunting...same thing if fuel delivery is suddenly rich- rpm will drop.

 

[rambojoe]

Oh my good god...thats not exactly your daddys wisconsin! You need to start at the beginning and send a fuel test to blackstone- or the supplier may take care of it..
That thing shouldnt have mystery issues...and why gas lordy?

 

[prajeesh thomas]

Check the mechanical governor...and as mentioned, if there is a intake leak, then the gov. could be just hunting...same thing if fuel delivery is suddenly rich- rpm will drop.

Hi, how the chance of intake leaks? This is happening a fraction of second and back to normal,if u said intake leak it should be a continuous hunting right?

 

[prajeesh thomas]

we checked and cleaned.no result

 

[hillbilly1]

Ever thought about a new motor? LOL! Since it does it under load, I would have thought as others maybe a coil issue, but you have already thrown parts at that to no avail. If it was propane, I would say low fuel volume, but it’s gas, and you said the pressure is good on that. I’m out of ideas. It’s probably something simple that’s just being overlooked, but what?

 

[hillbilly1]

Is this coil packs over the spark plugs? Or does it have plug wires? If so, have the wires been replaced? Real easy to see at night if you have a bad plug or coil wire. I think you said it’s electronic ignition, So shouldn’t be points, does it have a distributor?

 

[Beaches EE]

I know it was asked, but has the load changed? It almost sounds like something is spiking and dragging the engine down.

 

[prajeesh thomas]

Is this coil packs over the spark plugs? Or does it have plug wires? If so, have the wires been replaced? Real easy to see at night if you have a bad plug or coil wire. I think you said it’s electronic ignition, So shouldn’t be points, does it have a distributor?

the spark plug,extension and the coil replaced.both bank have seperate carburator.

 

[synchro]

I believe there is a high idle / low idle digital control input to the ECU. Are you using this? If you are, perhaps there is a loose connection or other issue causing it to drop into the low idle mode intermittently.

 

[prajeesh thomas]

I know it was asked, but has the load changed? It almost sounds like something is spiking and dragging the engine down.

Yes load is changing during the rpm changes. ya we also understand that but what? all the harness, major electronic parts were replaced.

 

[prajeesh thomas]

I believe there is a high idle / low idle digital control input to the ECU. Are you using this? If you are, perhaps there is a loose connection or other issue causing it to drop into the low idle mode intermittently.

yes we are using this. I will check that loop . but is that case the rpm should drops to the idle speed to 800rpm right? the rpm hunting from 1100 to 980.

 

[prajeesh thomas]

hi

yes we are using this. I will check that loop . but is that case the rpm should drops to the idle speed to 800rpm right? the rpm hunting from 1100 to 980.

we checked the low idle DI to engine .the wiring is ok .we are getting 24v dc.

 

[Metallicbeing]

Here's a shot in the dark. Check the Gain Setting on the Governor for the Hall Effect Sensor (Tachometer Sensing) near the flywheel. If it's not set right, the Governor will hunt RPM's.

 

[prajeesh thomas]

Hello All,
Finally we identified the problem after a long 10days troubleshooting. all the wiring and electronic components are fine, the problem was the front gear idler gear bearing was damage ,due to this engine time was changing intermittent during engine loading. replaced the bearing and now the engine is running perfect.This was the first experience in all of our team.

 

[prajeesh thomas]

thank you very much for all of your support.