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JSS1439's avatar
JSS1439
Explorer
Jul 29, 2014

Cummins Onan Generator running ruff at start up

Hi all, I have a Cummins Onan 5500 generator model HGJAB Spec E that on start up runs very ruff and smokes like crazy. It will stall out and give a 37 code about 3-4 times before eventually smoothing ...
ksg5000's avatar
ksg5000
Explorer II
Jul 30, 2014
Have you checked the spark plugs? If I recall code 37 is one of those generic faults which can mean lots of things -- I would rule out the basics first.

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