Engine dies when rapidly closing throttle
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Engine Repair
Forum Discription: Engine problems and solutions
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=51839
Printed Date: April-03-2025 at 11:14am
Topic: Engine dies when rapidly closing throttle
Posted By: Wilhelm Hertzog
Subject: Engine dies when rapidly closing throttle
Date Posted: December-21-2024 at 9:32am
My engine tends to die when I close the throttle suddenly - like when maneuvering at low speed to dock and having to quickly shift from forward into reverse. Searching the web suggests that:
Any thoughts on the above? Anything else that could be causing this? ------------- 1982 Ski Nautique PCM351W RR II Velvet Drive 10-17-003 1:1 II PerfectPass Stargazer Do not go gentle into that good night. Rage, rage against the dying of the light. |
Replies:
Posted By: KENO
Date Posted: December-22-2024 at 8:04am
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I think I'd richen the idle mixture using the 2 idle mixture adjustment screws on the metering block. If you're adjusted right now for max vacuum and you have a 150 rpm drop when putting it in gear like you say, richen things up going out about 1/8 turn at a time on both mixture screws and see how it acts. You should end up with less RPM drop( 50 to 75 or so) and better response going from neutral to forward or reverse
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Posted By: Wilhelm Hertzog
Date Posted: December-22-2024 at 3:04pm
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Thanks, I'll give that a try and report back. ------------- 1982 Ski Nautique PCM351W RR II Velvet Drive 10-17-003 1:1 II PerfectPass Stargazer Do not go gentle into that good night. Rage, rage against the dying of the light. |
Posted By: MrMcD
Date Posted: December-23-2024 at 1:58pm
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I think Ken is leading you correctly. My 78 Nautique had the same issue. West Coast Correct craft was only 10 minutes away back in the 80's when I had the issue. They gave me the same advice and it worked. Check your advance mechanism in the distributor to make sure it is rotating smoothly each and every time you advance and release the throttle.
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Posted By: Wilhelm Hertzog
Date Posted: January-11-2025 at 8:43am
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Richening things up a bit does seem to have helped, thanks Ken. I have subsequently developed a bit of an off-idle stumble when pulling away, but I'm sure a bit of fine tuning and adjustment will sort that out without too many hassles. ------------- 1982 Ski Nautique PCM351W RR II Velvet Drive 10-17-003 1:1 II PerfectPass Stargazer Do not go gentle into that good night. Rage, rage against the dying of the light. |
Posted By: KENO
Date Posted: January-11-2025 at 6:50pm
I'd probably start with checking that the accelerator pump linkage is adjusted correctly.......no slop at all with the carburetor at it's idle position.....none, not even a little Click on the link and you have a video and also a written procedure. You should have no need to change the cam or the nozzles. Make sure both nozzles are squirting a good stream when you give it some throttle. You can do this with the engine off and if you have the throttle cable disconnected, you can do it all by yourself looking down the primary side of the carburetor. If the stream isn't good, it could be the accelerator pump diaphragm being bad or dirty nozzles http://www.holley.com/blog/post/accelerator_pump_tuning_for_holley_carburetors/?srsltid=AfmBOoptqH8ZpHs4VakoiQnf2500_2y7t_nFgdPv581Y42Yh7q8u6gUR" rel="nofollow - link A little slop can make for a pretty bad bog. |