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Predator 420cc no start under load


Hattrik999's Avatar
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02-05-12, 02:42 PM   #1  
Predator 420cc no start under load

I bought a gas powered air compressor from harbour freight 3 years ago. Just had to replace the engine last week, because of spark and fuel issues. The replacement is now a 14hp 420cc Honda copy(Chinese). Right out of the box it ran fine...after installing it won't start. Checked the carb, plug, magneto, all fine. After hrs of checking and rechecking, I decide to back off the tension from the belt to drive the pump...wouldn't you know it it runs fine. After playing with the belt tension I found that it won't run under any kind of belt tension. Some how the tension of the belt on the shaft seems to be messing with the timing...and it's the second engine right out of the box. Need help!

Tom

 
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cheese's Avatar
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02-05-12, 07:34 PM   #2  
Sounds like the compressor is maybe too hard to turn? The belt tension can't affect the timing. What problems were you having with the last engine? Is this the same hp engine? If it runs without the compressor, the engine isn't the problem.


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06-12-12, 12:20 PM   #3  
Problem found

The pump is and was in great working order. Like I stated the engine is the problem. I bought all the parts required to rebuild the original engine, and have been using that engine with the same pump. Only problem it still leaves me uneasy as I don't have a backup engine ready to eliminate any down time.

According to the engine companies...EPA regs made Honda add a "decompression ring" somewhere near the cam. They only found the same issue when the couldn't get their own compressors to start either. Same issue under a load only. Apparently all the honda copies are using the same setup as I have tried two others with the same results. I havent tried a Honda yet, but might have to.

 
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06-12-12, 07:36 PM   #4  
I've got 3 honda powered compressors, all will start first pull, and with usually only a partial pull. I also had a compressor with a honda clone engine on it and it started and ran with no problems. They may have a compression release on the cam, but that shouldn't stop it from working.


"Who is John Galt?" - Ayn Rand (Atlas Shrugged)

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06-12-12, 09:36 PM   #5  
There should be an "Unloader" valve on the compressor to prevent it from starting under load.. All compressors have them.. They release air from the unit so it will start with no load.. You may have issues with yours.... It's usually part of the pressure switch...Also the check valve between the pump & tank may have issues Roger

 
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