#1
IP: 142.120.118.88
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Limited RPMs
I'm buying a 1975 C&C 30 with an Atomic 4 and about 5 days, 2 Great Lakes, and one major canal between her and home. The surveyor discovered she'd produce no horsepower in forward. This was traced to a now-replaced bolt in the clutch. The engine starts up easily and runs smoothly, but seems to produce only enough revs to get up to about 4 kts in calm conditions (there's no tach). Only the bottom one-fifth of the travel in the throttle control arm has any effect on the engine. The current owner says there's no issue with the control linkage. During the sea trial, he pulled the lead off cylinder 1, which stalled the engine. He suggested this indicated the cylinder was firing properly (otherwise the engine would run), but I notice elsewhere in the forum the A4s can run on two cylinders. Any thoughts on the seemingly limited revs/kts and/or the engine needing all cylinders, seemingly, to keep runnin would be much appreciated.
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#2
IP: 24.152.132.140
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Points to ponder
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Neil 1977 Catalina 30 San Pedro, California prior boats 1987 Westsail 32, 1970 Catalina 22 Had my hands in a few others |
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djmorris (09-03-2018) |
#3
IP: 99.30.185.198
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This is a classic description of how an A4 would die if plug wires 2&3 were crossed. In that configuration you'ld be trying to run your engine on 1 cylinder. Firing order should be 1 2 4 3.
Tom |
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Administrator (09-03-2018) |
#4
IP: 142.120.118.88
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Quote:
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#5
IP: 142.120.118.88
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Thanks, Tom. This is an intriguing possibility and so easy to confirm. We take possession of the boat on Saturday. At this point, I figure my first checks will be whether or not I can increase the revs at the carb by bypassing the linkage and whether the leads from the distributor "support" the firing order.
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#7
IP: 72.69.36.126
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I was in Kingston last weekend and received the worst haircut of my life in Gananoque. (About every ten years I get a bad haircut on a vacation and complain about it for the next eight years.) I’ve also been to Port Dover and through the Welland...but not lately.
Your symptoms are also reminiscent of a fouled prop (seems unlikely in Lake Erie), or a restricted exhaust. I agree it is weird to demonstrate the removal of plug 1, experience a stall, and not do the same for the other plugs. (My engine just slows down when you do that.) Other possibilities include a dirty or cracked cap, a worn rotor, bad plugs, or very bad plug wires. |
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djmorris (09-04-2018) |
#8
IP: 24.152.132.140
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Quote:
As for rebuilding, I'd suggest a barrage of tests before going there.
__________________
Neil 1977 Catalina 30 San Pedro, California prior boats 1987 Westsail 32, 1970 Catalina 22 Had my hands in a few others |
The Following User Says Thank You to ndutton For This Useful Post: | ||
djmorris (09-04-2018) |
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low rpm, low speed |
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