1984 SN 2001 - Holly Carb
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=29461
Printed Date: October-09-2024 at 3:16am
Topic: 1984 SN 2001 - Holly Carb
Posted By: n5891e
Subject: 1984 SN 2001 - Holly Carb
Date Posted: April-11-2013 at 11:36pm
| I just bought a 1984 SN 2001. Engine runs great however the carb seems to be running very rich. The smell of fuel is very strong. No leaks. New fuel line. I know my way around the engine pretty good however the carb I have no experience. Should I consider rebuilding the carb? Or, what adjustments should I try. Thanks for any help.. |
Replies:
Posted By: Gary S
Date Posted: April-11-2013 at 11:55pm
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First thing I'd do would be to call Holley tech support with the list number from the airhorn. That number will be able to tell them what the carb is. If you find that it is a 351 Ford marine carb they can tell you what rebuild kit number you need. Ask them what size jets are supposed to be in it. Get the kit and a 6.5 power valve to replace the one sent in the kit. Some kits do not have the secondary diaphram so ask that too and get one if you need it.Pull it apart,clean it and reassemble it. If it isn't a marine carb,ditch it and get a new one. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=1711&sort=&pagenum=1&yrstart=1966&yrend=1970" rel="nofollow - 69 Mustang HM SS 95 Nautique Super Sport |
Posted By: cphase
Date Posted: April-12-2013 at 12:05am
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With the boat running, flame arrestor off does the primary's drip? Good chance it needs rebuilding. I like using http://daytonaparts.com/" rel="nofollow - Daytona Parts kits, they come with a secondary diaphragm and a carb to manifold gasket. You will need to get an extra gasket to go between the spacer and carb and if you want a 6.5 power valve you will have to specify since it comes with a 2.5. Their kits are nice, I just ordered two. ------------- Thanks, Jeff http://www.correctcraftfan.com/diaries/details.asp?ID=6549" rel="nofollow - 82 SN http://www.archlinux.org" rel="nofollow - Arch Linux |
Posted By: Foot_Fungus
Date Posted: April-12-2013 at 12:49am
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It probably will need a rebuild, but that doesn't mean it needs to be done pronto. First thing I would do would be turn the idle screws on the primary(front) bowl in all the way(gently). Then back them out 1.5 turns. Then I would start her up and pull the view plug out to make sure your bowl level is set correctly(if you have one it is the plug on the front bowl starboard side). You want it just below the bottom of the hole, maybe even dead even with the bottom of the hole depending on how level the engine is. As far as a rebuild kit, as indicated pull the #s off the front of your carb at the base of the airhat, then call holley. Most of holley's newere kits include a base gasket and secondary diaphram now. You can ask the tech rep which pv it will come with as it depends on your model. Most of their marine kits come with a 2.5, but a few of their newer style kits come with a 5.0(mine did). None I'm aware of come with a 6.5(part # 125-65), so you'd need to order that additionally if you decided you needed it. 2.5 will work just fine, however a lot of people on here have seen positive results in mid throttle response with the larger # PV. Its in the front metering block and takes about 2 minutes to get to, so don't think you have to make a decision to go with a 6.5 now. You can always swap it later. Most on here would suggest you stick with a holley brand kit. Cheapest I've found lately has been through summitracing who also carry the power valves and extra gaskets for cheap. Since you should probably do a tune up as well they also happen to have the cheapest price on the autolite 764s I've seen. ------------- '94SN Restoration underway... |
Posted By: Waternut
Date Posted: April-12-2013 at 2:06am
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I want to back up a step. A rebuild is certainly a good idea and if you know your way around an engine, a rebuild shouldn't be hard. However, what makes you think it's running rich other than smell? You say the engine runs great but is there some performance aspect or idling quality that is leading you to believe the carb is to blame? I'd hate to see someone spend good time and money on something that is actually working perfectly. ------------- |
Posted By: n5891e
Date Posted: April-14-2013 at 4:03am
| The smell of raw fuel is very strong when running. Especially from the back of the boat. Also the boat vibrates more than it should at idle and the engine seems to lope. Engine runs and sounds normal at higher rpm. |
Posted By: Foot_Fungus
Date Posted: April-14-2013 at 10:25pm
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see my post above, set/check your idle mix screws and then adjust your idle speed to 800-900rpms. Of course I'm assuming you've checked for leaks while its running. If none of that fixes it then I'm with nut its time to tear her apart. Especially since you have no clue about the condition previously. For all you know the PO could of had the wrong jets in it. ------------- '94SN Restoration underway... |
Posted By: Waternut
Date Posted: April-15-2013 at 12:25am
It probably is a carb setting but it can't hurt to make sure your fuel tank vent is actually connected to the fitting on the hull and not pumping fuel vapors in the boat. If it fell off, the fuel vapors would be really bad at the back of the boat too. ------------- |
n5891e wrote:Posted By: n5891e
Date Posted: April-20-2013 at 9:13pm
| The primary does not drip when at idle, However, when the trottle is applied there is a thick jet stream spray and heavy dripping below the jet stream spray. The dripping continues for 2 or 3 drips after throttling back to idle. Does this sound like a rebuild is in order? |
Posted By: Foot_Fungus
Date Posted: April-21-2013 at 2:03pm
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thats your accel pump shooting a stream when you juice the throttle, which is what its supposed to do. Nut makes another good point. Seems you have some settings to check and a vent to check before we can help you any further. Let us know, carbs are simple, but finacky, creatures. ------------- '94SN Restoration underway... |
Posted By: JasonR
Date Posted: April-25-2013 at 7:25pm
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Verify the choke is fully open. What does the plugs look like? ------------- '86 2001 800hrs |
Posted By: n5891e
Date Posted: May-01-2013 at 12:23am
| Ok. Still working on the possibility of a re build. Today under cold engine condition I removed the rubber cap from the vacuum stud picture below. About a table spoon of fuel poured out. Ok. Can't figure out how to post image. |