Various carb questions
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=30035
Printed Date: November-18-2024 at 6:39am
Topic: Various carb questions
Posted By: M3Fan
Subject: Various carb questions
Date Posted: May-29-2013 at 1:18am
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I'm packaging several questions into one convenient post here. 351 w/4160. Last rebuild of carb unknown. Boat runs very well right up to WOT. Great hole shot, great WOT, the whole bit. Starts and hot/cold idle can be rough and at idle the boat will eventually choke itself out with an overly rich mixture after a few minutes of idling. Idle adjustment screws do basically nothing. Culprit found to be primary dripping gas during idle and after shut-down. I understand this to be a bad float, a gunked up needle valve, or a mis-adjusted float. 1. SO. Do I just take off the front bowl and attack the primary float/valve issue OR... 2. Do the WHOLE rebuild kit while I have it? And 3. When I put the carb back onto the boat, do I have to "prime" it somehow to fill up the float bowls, accel pump, etc? 4. Any gasket sealer on gasket to manifold? ALSO 5. The motor appears to have http://www.jegs.com/i/Holley/510/108-70/10002/-1" rel="nofollow - this heat shield under the carb. The gasket below it is pretty thick, potentially a stack of gaskets though reading this it looks like it comes with a thick lower gasket and that's probably what it is. Is this necessary? 6. I saw updated bowl screws on Skidim. Do I need these? The carb I have has flathead screws holding the bowls on 7. Anything else I should do "while I'm in there"? ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |
Replies:
Posted By: Gary S
Date Posted: May-29-2013 at 2:21am
Joel my thoughts are since you don't know if or when it was gone thru,if you feel comfortable do it,you have to pull it off anyway. As to restarting it,it's easy just to remove the spark arrestor and dump a small amount of gas into the carb. Put the arrestor back on before you try to start. You might have to do this 2-3 times,careful not to spill any fuel. No on the sealer just use new gaskets,I'd just reuse the plate since you have had no other problems. Some gasket sets come with that thick gasket,some how I ended up with one I never used,don't know which kit it came from but I have only used Holley kits. As to the upgraded bolts you only need these if you have the original phillip headed screws that have the springs on them which I don't think you have. I'll dig one up for a picture if needed. I also think it was Alan who recommended a 6.5 power valve,the new kits come with a 2 or something. If you can find some type of gasket remover it will make your life easier. Others here have recommended http://www.daytonaparts.com/findyourcarb.html" rel="nofollow - this place for kits too. ------------- 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: TRBenj
Date Posted: May-29-2013 at 8:27am
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Ditto what Gary said. Idle screws unresponsive = plugged idle passages, so you're pulling off the front bowl and metering block to clean and blow out. Might as well do the back bowl at the same time. Grab the list number off the choke horn and call Holley to find out which rebuild kit you need... Make sure they point you to one with the reusable (blue) gaskets. Don't forget to pick up carb cleaner and a few cans of compressed air if you don't have a compressor up north! You'll need 5/8" and 1" wrenches for the fuel line. Pick up some JB weld just in case the soldered plugs weep after the rebuild (this is common). I'd ditch the heat shield. ------------- |
Posted By: M3Fan
Date Posted: May-29-2013 at 8:52am
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So definitely do the whole enchilada, then. Kinda looking forward to it, actually! ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |
Posted By: backfoot100
Date Posted: May-29-2013 at 10:29am
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I also concur. Do the whole rebuild. I might add one other helpful hint. Pouring some gas in the carb throat to initially start it does work but can be a little dangerous. I've done it before myself. I've started pouring a small amount of gas in a cup of some sort. If you have access to a small syringe, you fill it with the gas from the cup and then squirt it into the vent tube. Repeat several times. Now you need a syringe small enough to be able to fit in that small area between the vent tube and the choke horn but it does the job. ------------- When people run down to the lake to see what's making that noise, you've succeeded. Eddie |
Posted By: catamount
Date Posted: May-29-2013 at 12:39pm
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Hi there. I browse this forum as I have an old MC and the problems/fixes typically overlap. I actually just rebuilt my old 4160 due to the exact same problem (choking out at idle). I posted my rebuild experience over on our forum, but it might be useful to you. If your throttle body is pre 1992, it's worth adding the backfire protection to your power valve (detailed in the thread). Good luck! http://www.mastercraft.com/teamtalk/showthread.php?t=54417" rel="nofollow - http://www.mastercraft.com/teamtalk/showthread.php?t=54417 ------------- 1987 MC ProStar 190 |
Posted By: ny_nautique
Date Posted: May-29-2013 at 1:02pm
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Nice writeup catamount. Thanks for sharing. That ultrasonic cleaner really did a good job. I see it at http://www.harborfreight.com/25-liter-ultrasonic-cleaner-95563.html" rel="nofollow - Harbor Freight for $79.99. Here's http://www.correctcraftfan.com/forum/forum_posts.asp?TID=24175" rel="nofollow - another writeup done for an 88 SN 2001. ------------- - Jeff 1999 Ski Nautique |
Posted By: M3Fan
Date Posted: May-30-2013 at 11:03pm
Holy cow, that's a nice thread! The rebuild kit as about 18 Bazillion parts in it and no real instructions so this is helpful. Funny you should mention MC, this carb is on my "impostor" boat, the http://www.flickr.com/photos/m3fan/sets/72157631025694122/" rel="nofollow - 1983 MC S&S !!! This hull skis like a dream considering the vintage. And, no wood. Ergonomics are for an oompa loompa, but other than that it's tough to beat for the price! Gel work is pretty much ridiculously amazing— all the stripes and pinstripes are GEL, both on the deck and on the sides of the boat.  ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |
catamount wrote:Posted By: Bri892001
Date Posted: May-31-2013 at 12:18am
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Awesome thread Catamount. That's the best 4160 rebuild writeup I've ever seen. Couple of nice looking Prostars as well. |
Posted By: TX Foilhead
Date Posted: May-31-2013 at 2:37am
| Use the thick gaskets, I've heard PCM uses them to help with vapor lock. |
Posted By: ny_nautique
Date Posted: May-31-2013 at 8:45am
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Justin I just purchased the same ultrasonic parts washer at http://www.harborfreight.com/25-liter-ultrasonic-cleaner-95563.html" rel="nofollow - Harbor Freight last night ($66.xx with coupon). I'll be using it to clean my carb and various parts this weekend. ------------- - Jeff 1999 Ski Nautique |
Posted By: M3Fan
Date Posted: June-01-2013 at 10:06pm
Gang, the deed is done. I have to say that pulling that carb apart and replacing everything inside was IMMENSELY satisfying. Almost to the point where it was a little weird.  Gasket removal was the only negative of the job, and it wasn't really that bad. I could tell that somebody had been in the carb before- little scrape marks here and there. But, it was a long time ago by the look of the gaskets. So, this is at least the 2nd rebuild, but the carb IS 30 years old!Won't get to figure out whether the rebuild worked or not for another 2 weeks when I get back up to the cabin.  ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |
Posted By: catamount
Date Posted: June-02-2013 at 12:27am
Thanks guys. And OP, great work rebuilding yours! It's satisfying for sure.
Hey, that is really cool! I think you'll like it. This is a Keihin motorcycle carb I cleaned this past winter. I use a 3 part water, 1 part Simple Green solution. There are lots of other suggestions out there as far as solutions go. This carb was caked in grime before I gave it a long bath in the ultrasonic. When it came out, it looked new.  One note, if you put aluminum parts in with Simple Green be sure to turn them every 10 minutes or they may get stain lines. ------------- 1987 MC ProStar 190 |
Posted By: M3Fan
Date Posted: June-17-2013 at 2:08am
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Little update here on this thread. After rebuilding the carb, problems still persist. The primary venturis are no longer dripping, which shows that problem was solved. But, boat still extremely hard starting and can barely idle in gear. I believe this still to be a rich condition and I think the carb is feeding gas in below the throttle plates but not via the idle circuit. I think the dripping we had going on before actually fed it at idle because post-rebuild the idle is much worse to the point where the boat would only run at about 800 RPM or above. As in fixing one problem exposed another. Idle mix screws did little to nothing at any amount of turns. Played with the secondary idle set screw adjustment too and made sure that was set right (one quarter turn past first contact). Made no difference. The carb looks really worn and corroded. It is 30 years old. I refuse to invest any more time on the bench with the carb and vacation/cabin time screwing with it so I'm biting the bullet and ordering a new one. Boat 1, M3Fan 0 ------------- 2000 SN GT40 w/99 Graphics/Gel 2016 SN 200 OB 5.3L DI https://forum.fifteenoff.com |