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Kohler 7 3E
Posted: August 10th, 2025, 9:11 pm
by pepmyster
Hey everyone. Been a while since posting because everything was Hunky Dory. Until. Genny started great, 110v , beautiful. Turned on shore power 1, great. Then shore power 2 and when the ac kicked in, Back fires......So I'm going to start with replacing the plugs this weekend unless someone has had this happen before to them. I changed the plugs in 2017 when I bought the boat. Thanks for reading.
Re: Kohler 7 3E
Posted: August 18th, 2025, 2:46 pm
by pepmyster
Not much chatter on this thread. Are you guys all out there boating????? I hope so! Anyway, Took apart the casing, lubed the linkage for the carb, which was fine, looked around, all levels great. Proceed to replace the 2 plugs, NGK BPR4ES. Afterwards, restart the genny. A1 now. NO back fires, starts like a champ etc. All to say, you have to start with the simple things first. Ciao!
Re: Kohler 7 3E
Posted: August 18th, 2025, 7:52 pm
by Viper
Agreed, simple things and the basics first. Even if they don't solve the problem, you've eliminated a possibility, and that's an important part of the diagnostic process.
Re: Kohler 7 3E
Posted: August 18th, 2025, 8:39 pm
by Carverlvr2
Glad you got it ironed out! I also have a 2004 with same genny and it’s been very hard starting. Like 3-4, 10 sec cranking sessions to get it to fire. PO says plugs were just replaced in ‘23 but now wondering if they’re even the right ones. You listed the NGK BPR4ES and I’ve seen those and the 6 version and a few others listed and all claim these gens are very sensitive to plugs. So glad to hear your success and thanks for listing exact plugs. What’s your crank time?
Re: Kohler 7 3E
Posted: August 18th, 2025, 10:19 pm
by pepmyster
Your welcome. About 4-5 seconds to start.
Re: Kohler 7 3E
Posted: August 18th, 2025, 10:30 pm
by Carverlvr2
Wow! Was it that quick before the new plugs?
Re: Kohler 7 3E
Posted: August 19th, 2025, 8:33 am
by pepmyster
No, A bit longer. But ran great until the large load went on.
Re: Kohler 7 3E
Posted: August 19th, 2025, 9:10 am
by bud37
My experience was that sometimes the idle jet can become partially restricted, remove the float bowl and clean as residue collects in the bottom which can affect operation. The governor spring also appeared to get weak over time, I just put one twist on it and re-installed, no hunting and much smoother, but that was just a shade tree for my case.
Re: Kohler 7 3E
Posted: August 19th, 2025, 10:56 am
by Carverlvr2
Bud37, thanks for those tips! I’ll give both a try along with new plugs and fuel filter next time I’m out there!
Re: Kohler 7 3E
Posted: August 20th, 2025, 8:42 am
by pepmyster
bud37 wrote:Source of the post My experience was that sometimes the idle jet can become partially restricted, remove the float bowl and clean as residue collects in the bottom which can affect operation. The governor spring also appeared to get weak over time, I just put one twist on it and re-installed, no hunting and much smoother, but that was just a shade tree for my case.
Could not agree more. That’s something I should have done while there. I’ll remove the bowl and check(preventive) for debris.