| Won't idle without choke [message #363522] |
Mon, 19 April 2021 10:37  |
indymac
Messages: 26
Registered: August 2013
Location: Decatur, IN
Karma: 0
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Junior Member |
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77 403, starts fine on choke, the dies as soon as choke drops off.
It's been sitting a while, gas old mixed with new, new fuel pump with electric pump kicker, inline fuel filter, new carb filter, lost spring, got one at hdwr store, not sure if it's the right one..
Any clues on where to start?
Thanks,
Jim
77 Palm Beach 403
Decatur, IN
TZE167V101738
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| Re: Won't idle without choke [message #363524 is a reply to message #363522] |
Mon, 19 April 2021 11:13  |
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Matt Colie
Messages: 8547
Registered: March 2007
Location: S.E. Michigan
Karma: 7
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Senior Member |
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indymac wrote on Mon, 19 April 2021 11:3777 403, starts fine on choke, the dies as soon as choke drops off.
It's been sitting a while, gas old mixed with new, new fuel pump with electric pump kicker, inline fuel filter, new carb filter, lost spring, got one at hdwr store, not sure if it's the right one..
Any clues on where to start?
Thanks,
Jim
Jim,
The idle circuit is very possibly fouled because of the old fuel. If you pour some fuel system cleaner in there, it might clear out. But until it does, try adjusting the idle stop to get by. This will only be temporary and be real ready to take out what you put in. So, count how much you do. I always count quarter turns because it is easy.
The idle mixture screws are under the float bowl and a bear to get to without the proper tool. Just leave them alone as long as you can.
Matt
Matt & Mary Colie - Chaumière -'73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan with OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Near DTW - Twixt A2 and Detroit
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| Re: Won't idle without choke [message #363539 is a reply to message #363529] |
Tue, 20 April 2021 01:32 |
Ken Burton
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
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Senior Member |
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A couple of years ago I was working on restarting a 1978-403 that had sat for 19 years. After starting it, it ran very poorly and had similar running lean problems after warm up. I went to an engine replacment site where Dick Paterson was working and in passing I asked him what I should do about the carb. His e suggestion was to fill the carb on the engine with 100% carb cleaner and let it sit for a day or so. I did that and after cranking enough to get some of the cleaner out, the engine started and it runs perfectly. I wish my 455 started and ran that great.
You might want to try that.
Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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