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318 with Honda not charging

2712 Views 11 Replies 5 Participants Last post by  tpndrcn
I have a 90' 318 with a GX620 Honda repower and recently it has quit charging the battery. I checked voltage with it running and it doesn't increase ,leading me to the charging issue. Any help you can give me on this would be appreciated. Thanks
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When it was repowered, did you retain the original regulator or ???
Need more info/wireing data to help.
I did not do the repower , I purchased it that way 2 years ago. I am not sure if it has the original regulator or not, where is it located ?
It would have been on the Onan. Could have been relocated anywhere, or replaced with a different reg. You are going to have to chase the wiring down. Should be two wires coming from under the flywheel to wherever it is located. Check the voltage at those, disconnected and engine running. It will be AC and probably over 28v at half throttle.

If you have that, it's likely the reg.
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Yeah I took a quick look and didn't see the original regulator, but I will have to spend more time chasing the wires from the flywheel and check voltage like you said. I will keep you updated ,thank you
I have had a chance to check VAC on the two wires coming from the charging coil by the flywheel and I am on getting a .9 reading and not much change in throttle position, which leads me to believe I have a faulty coil. The regulator /retifier is a honda unit with 6 wires so should be a 20 amp. Anymore thoughts on my coil or am I doing the test wrong? I put the two leads on the wires from the flywheel with the tractor running and volt/ohm meter set to VAC. Thanks
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You are doing the test right. Typically garden tractor charge coils will put out somewhere above 28vac. However being a repower you don't know what is in it. But we do know the 318 needs more than its putting out. Cast into the side of the block is the model number and serial number. If you take those numbers into a Honda dealer they should be able to get you a charge coil and voltage regulator with the out put you need.
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A possible theory is that the original Honda charge coil was too small and the 318 ran it at its limit until it burnt out.
It would be handy if a 318 expert could chime in with the 318 onan amp spec.
I guess I would go here
to start and see what manuals I could find on the Honda. It appears to come with a 20A charging system which is equivalent to the Onan. I think your test so far is a good one... I don't know anything about the Honda but electromagnetics hasn't changed in a couple hundred years at least... my experience is the AC voltage from stator with engine running should be in the 20 --> 40 VAC range and vary with engine rpm. Since the Honda is not original, you'll have to see how the wiring was adapted to 318.
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Usually first thing to go on these engines is the regulator. It's a little black box with cooling fins. Unregulated, it should produce about 15 volts. If there is nothing, my guess the stator is bad.


Thanks for all the help guys. I am sure that because I don't have barely any voltage from the stator coil , that it is bad and need to be changed!
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