Holley help. Dripping primary after rebuild.
Printed From: CorrectCraftFan.com
Category: Repairs and Maintenance
Forum Name: Boat Maintenance
Forum Discription: Discuss maintenance of your Correct Craft
URL: http://www.CorrectCraftFan.com/forum/forum_posts.asp?TID=25570
Printed Date: November-19-2024 at 5:39am
Topic: Holley help. Dripping primary after rebuild.
Posted By: C-Bass
Subject: Holley help. Dripping primary after rebuild.
Date Posted: April-13-2012 at 10:59am
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Alright, I rebuilt the carb on the 85 and things were pretty uneventful. Soaked in carb cleaner and followed all the recommendations from previous discussions on here. I put it back on the boat and it fired right up. I used a vacuum gage to set the idle mixture screws. Then I rev'd it up to check the accelerator pump and it worked as well. After the RPM's dropped back down to idle I noticed fuel dripping out of the primary venturi. The boat procedes to idle like crap. So I bring it off idle a few times and this problem continues. I diagnose it with a dirty needle/seat on the primary side. So I take off the primary bowl and remove the seat and clean it up and make sure there is no debris, spray real well with carb cleaner, reassemble, and restart. Same issue. The thing that stumped me is sometimes it would drip out of the port venturi, other times it would be the starboard venturi, and other times it would be fine. If it were debris in the needle/seat, why is it switching sides. And why after I cleaned it really well? Could the rebuild kit just have a bad needle/seat? I'm thinking about pulling it back off and trying the original just to check. ------------- Craig 67 SN 73 SN http://www.correctcraftfan.com/diaries/details.asp?ID=6103" rel="nofollow - 99 Sport 85SN |
Replies:
Posted By: C-Bass
Date Posted: April-13-2012 at 11:29am
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Oh I forgot to add...I did check the float level also (by inverting the bowl) and it was perfectly level. I even lowered the level a bit to see if that would help and it did not. ------------- Craig 67 SN 73 SN http://www.correctcraftfan.com/diaries/details.asp?ID=6103" rel="nofollow - 99 Sport 85SN |
Posted By: Waterdog
Date Posted: April-13-2012 at 11:32am
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Could still be the needle and seat. While your in there ajust the primary float up 1/32 (just a tick) I think its set about perfect but with running the engine,vibration, moving around ect its just a little high. The venturi effect is sucking gas out of the bowl. ------------- - waterdog - http://www.correctcraftfan.com/diaries/details.asp?ID=3896&sort=&pagenum=2&yrstart=1978&yrend=1978" rel="nofollow - 78 Ski Tique |
Posted By: JoeinNY
Date Posted: April-13-2012 at 11:40am
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It is possible you have a bad needle and seat, even though it is newish. On on of Reidp's mustangs he had a set of secondaries on a new carb that leaked like a son of gun right off the bat. The first time I took it apart I found some metallic debris, but after cleaning it out and putting it back together the damn thing leaked again... and again.. .and again.. and so forth regardless of setup cleanliness etc until one day I finally pulled a bowl off a crusty arse old parts carb (the original from my 83 SN that had never been rebuilt) and haphazardly put it on and it worked like a champ. My original intent was to have my buddy dan blow up the entire float bowl.. but eventually curiosity got the better of me and I changed the "new" needle and seat for another "new" needle and seat and the bowl worked fine. That being said I would at least pull the seat out first and give her a look make sure it is screwing in all the way with no debris under it etc and then be prepared to change it out. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1477 - 1983 Ski Nautique 2001 1967 Mustang 302 "Decoy" http://www.youtube.com/watch?v=cO5MkcBXBBs - Holeshot Video |
Posted By: C-Bass
Date Posted: April-13-2012 at 11:57am
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Yeah I pulled the seat out last night and gave it a good look. It looked fine, and I went ahead and cleaned it anyway. I kept the old parts from the rebuild so I guess I'll throw the old needle/seat back in and see what happens. The switching from one venturi to the other still confuses me though...  ------------- Craig 67 SN 73 SN http://www.correctcraftfan.com/diaries/details.asp?ID=6103" rel="nofollow - 99 Sport 85SN |
Posted By: backfoot100
Date Posted: April-13-2012 at 12:08pm
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+1 on what Andy and Joe stated. My experience is that setting the float as it states in any Holley documentation is too high with these engines angled the way they are. Even if you have an angled spacer they still can lean toward the back a little bit. If you don't have the spacer it's even more so. The float adjustments are pretty much based on automotive applications. They don't have near the angled engine installations that we experience as a rule. I would set the float a little lower myself. ------------- When people run down to the lake to see what's making that noise, you've succeeded. Eddie |
Posted By: C-Bass
Date Posted: April-13-2012 at 12:31pm
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I will try lowering the float a little more, but it was in the exact same position as it was before I rebuilt the carb, and I already lowered it about 1/16" to check and it still had the same issue. If it was the float level, wouldn't it be a consistent issue, and not intermittent? Thanks for the advice guys. It's appreciated. ------------- Craig 67 SN 73 SN http://www.correctcraftfan.com/diaries/details.asp?ID=6103" rel="nofollow - 99 Sport 85SN |
Posted By: lakedog55
Date Posted: April-13-2012 at 12:33pm
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I am going with lowering the float. ------------- Lakedog55 |
Posted By: C-Bass
Date Posted: April-13-2012 at 8:57pm
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Update* Changed the primary needle/seat back to the old(original) set. Put it back in the boat, fired it up, and the problem is gone. Coming down off of higher RPM the primary venturies stop dripping gas immediately and it returns to the idle circuit for a nice smooth idle. So evidently there was something going on with the rebuild kit's needle/seat. Oh well...problem solved. Thanks for the input guys. ------------- Craig 67 SN 73 SN http://www.correctcraftfan.com/diaries/details.asp?ID=6103" rel="nofollow - 99 Sport 85SN |
Posted By: Waterdog
Date Posted: April-13-2012 at 9:00pm
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I lova a happy ending. Good on ya! ------------- - waterdog - http://www.correctcraftfan.com/diaries/details.asp?ID=3896&sort=&pagenum=2&yrstart=1978&yrend=1978" rel="nofollow - 78 Ski Tique |
Posted By: Bri892001
Date Posted: April-14-2012 at 7:39pm
I think I know the answer. When I was having a similar booster leak, I had talked to an auto mechanic who rebuilds Holleys. His explanation basically made sense to me: The fuel will basically leak out of the booster with the lower pickup point. Lower meaning, lower at the moment, so if the boat/car where a bit tilted to one direction or another, it would change it. I read up on this a bit and there is something called the "Main Well" which is kind of like mini-resovoir and staging area for the fuel. Both the Main Jet(s?) and the power valve let fuel from the bowl into the main well. So, I think once excess fuel has made it's way into the main well, it's probably related to tilt, which booster is going to wind up leaking it. One thing I'm confused on, I always thought there were multiple main jets, but if both boosters share one main well, I would think there would only need to be one main jet. |
C-Bass wrote: