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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 ...
nuggetthunter's avatar
nuggetthunter
Explorer
Jul 30, 2014
Yes, the vacuum breaker is the same part. The vacuum breaker is designed to gradually open the choke when the generator is running until the unit is warm enough for the mechanical choke pull off to overcome it. You may not be able to remove the vacuum hose to check it with the breaker installed. Very short hose in close quarters.

If you need it the replacement part number is:
Vacuum Breaker Kit A043B658 (Old Kit # 170541-1222)

Hope this helps you out.

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