| rough idle and stalling [message #365993] |
Sun, 08 August 2021 23:02  |
boybach
Messages: 566
Registered: December 2020
Location: Vancouver Island
Karma:
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Senior Member |
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Yes well I just got back from a trip up-island as we say around these parts. While the outbound journey was nice and uneventful, starting up the following day I felt my idle was too low. At first I thought I'd kicked off the choke too early because she stalled every time I put her in reverse, but it was more than that.
Eventually I was able to back up and leave my spot but was a bit concerned at traffic lights etc as she did not sound like her usual smooth self, now all lumpy and on the brink of stalling. Getting home was a bit stressful as I was convinced she was going to die at every traffic light but fortunately she kept running, even though it was super rough. At road speed, everything seemed normal, bags of power and roaring uphill as usual.
Today was lets-have-a-look day and what I found when I took off the air filter (this description is of the 403 looking at the engine from the step with the hatch open) was a formed 1/8" steel hose with a 1" long rubber hose attached to closest end sitting under the carb, lying loose on the intake.
The hose end at one time was attached to the carb, it had fallen off the rightmost vacuum attachment nearest to me and the other end had at one time been attached to a plate bolted to the right side intake manifold. This tube had corroded at the manifold connection so basically it just fell off.
There are two steel lines that terminate at the plate bolted to the RH side of the intake, one (the intact one, closest to me) has a flared fitting that leads to the automatic choke mechanism. It's connected with a brass nut. The other, (the broken one, further forward) attaches to the carb directly with a bit of hose.
The problem was how to attach it. I cut a section of small brass tubing and soldered it to broken pipe then forced it into the manifold sealing the whole joint with JB weld Hi-heat putty.
So far so good. Idle stable again. Fingers crossed!!
Larry
Larry - Victoria BC -
1977 ex-Palm Beach "Ol' Leaky" 40,000 miles, PO said everything working but forgot the word NOT. Atwood helium fridge, water heater & furnace. SS exhaust system, Onan, Iota Converter, R134A, New fuel lines & heat exchange hoses
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