Wandering Idle
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=7174
Printed Date: November-15-2024 at 6:10pm
Topic: Wandering Idle
Posted By: Zonour
Subject: Wandering Idle
Date Posted: June-20-2007 at 11:02pm
I have a'79 Southwind with 970hrs on it. PCM 351 Ford runs strong off idle, and pulls really well. Tune up included new plugs, wires, cap, rotor, points and condenser. The carb looked filthy so I had it rebuilt by a very good mechanic. Timing is at 8 @ 600 rpm, dwell shows 30 with .019 point gap (pretty close to the specs in my manual). Compression check ranges from 105-130. I have been chasing the idle. After coming down from speed, the idle will hang up at 1100-1200rpm and drop about 100 RPM per minute and settle near 1000. Doesn't matter if I disconnect the cable. I re-torqued the intake bolts and sprayed ether around to find a vacuum leak, negative. If it gets much below 1000 in neutral, she will stall in gear. Vacuum is 16.5-17.5 at idle and does jump a little. It is drivable but annoying and I'm looking for some ideas to dial it in better. Have at it folks!!!
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http://www.correctcraftfan.com/diaries/details.asp?ID=5609&sort=&pagenum=3" rel="nofollow - '02 Ski Nautique 196 SE
[URL=http://www.correctcraftfan.com/diaries/details.
asp?ID=1627&sort=&pagenum=1&
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Replies:
Posted By: 79nautique
Date Posted: June-20-2007 at 11:34pm
sounds like the mechanics isn't to sharp with carbs.
Double check the spacer plate and make sure it's flat, but most likely it's in the carb sucking air somewhere and most likely the mechanic didn't use a holley renew kit.
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http://www.correctcraftfan.com/diaries/details.asp?ID=756&sort=&pagenum=1&yrstart=1979&yrend=1979 - 79 nautique
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Posted By: JR_VIC
Date Posted: June-20-2007 at 11:42pm
I have experienced the same thing. Last year in August I bought a brand new DUI distributor which overall I have been very happy with. This year I after getting my engine back together I have been attempting to fine tune the carb that is also hanging around 1,100 to 1,200 after running across the lake at 2,600 RPM's. If I trn off the engine and immediately start it back up the idle will come back down to 800 RPM where it I have it set at. A friend said the springs/weights are sticking in the distributor which I did not think was possible because it is a new distributor not even a year old.
So last night on the trailer, after the engine warmed up I held it around 2,700 for 5 seconds and let off the throttle (I also had the throttle disconnected) and again the RPM's just held at 1,150 RPM's. I put on the timing light and the timing was at 20 degrees. I turned off the engine and immediately started it back up and it was right at 14 degrees where I have it timed at. I did not think that would happen but I am going to pull the distributor and try to lube those springs somehow.
Before you go taking your intake off to replace the gaskets or chasing the carb gaskets check your timing to see if it does the same thing. Hope that helps...
Thanks!
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"That's not a Snow Cone that's my Ring!"
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Posted By: Zonour
Date Posted: July-17-2007 at 1:18am
You guys may be wondering why I posted the same problem under "Huntin' for an Idle" but I thought this didn't make it out as my computer crashed the night I typed it up. Sorry for the confusement.
The carb from my '88 worked like a charm on the Southwind so it is in the carb or plate. Replaced the power valve but no improvement- will swap the spacer as it sounds like there may be some type of internal vacuum leakage (I hear it suck at around 900-1000 rpms). Maybe the thing warps when it warms up. I also noted that the Nautique spacer is about 1/4" thicker.
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http://www.correctcraftfan.com/diaries/details.asp?ID=5609&sort=&pagenum=3" rel="nofollow - '02 Ski Nautique 196 SE
[URL=http://www.correctcraftfan.com/diaries/details.
asp?ID=1627&sort=&pagenum=1&
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Posted By: GottaSki
Date Posted: July-17-2007 at 1:30am
Secondary plates can hang open, providing the air leak.. Adjust (bend) the rod than forces then closed so there is no slop.
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"There is nothing, absolutely nothing, half so much worthwhile as messing around with boats...simply messing."
River Rat to Mole
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Posted By: Zonour
Date Posted: July-18-2007 at 9:58pm
Thanks again, I checked it and there was some play that I eliminated by bending the rod as you mentioned, but it made no difference. I even tried to close them by hand when it hung up but they were closed when it was up high.
Also, the parts for the rebuild were from Skidim , which I recall being from Holley. I just have to get back out there and try the plate swap before I make my next move. I'm just glad it's not a bigger problem.
Next consideration: where to get another spacer plate? Or to replace it with new or reman if I can't dial it in?
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http://www.correctcraftfan.com/diaries/details.asp?ID=5609&sort=&pagenum=3" rel="nofollow - '02 Ski Nautique 196 SE
[URL=http://www.correctcraftfan.com/diaries/details.
asp?ID=1627&sort=&pagenum=1&
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