carb adjustment question
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=25792
Printed Date: November-19-2024 at 3:49am
Topic: carb adjustment question
Posted By: rtsuggs
Subject: carb adjustment question
Date Posted: April-30-2012 at 10:58pm
|
My boat is hard to start after it sits for a few minutes. If I shut it off and restart it, it fires right up but if it sits a few minutes I have to pump it to make it crank and it turns over several times before starting. The carb was just rebuilt and sits on a 351 RH in a 85 nautique. What do I need to do? Thanks ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=5143" rel="nofollow - 78 nautique 78 ski nautique SOLD 85 ski nautique |
Replies:
Posted By: hotboat
Date Posted: April-30-2012 at 11:27pm
|
When you shut it off, remove the flame arrestor and see if it drips or runs fuel down into the motor, if so and is in the front 2 barrels remove front fuel bowl and adjust float level (bend) to lower the fuel level in the bowl, if rear do rear ------------- Brian |
Posted By: rtsuggs
Date Posted: April-30-2012 at 11:37pm
|
Yea I'll try that. I had to do the rear because it was flooding fuel out the little curved over flow tube. Thanks ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=5143" rel="nofollow - 78 nautique 78 ski nautique SOLD 85 ski nautique |
Posted By: levinmark
Date Posted: May-01-2012 at 9:59am
|
Robbie, I had the same issue with our 96', pulled the flame arrestor after a run, and sure enough fuel was dripping and puddling in the front two bowls. When back at home, took off fuel bowl, adjusted float, and problem solved. Pretty simple fix to an annoying problem. ------------- levin |
Posted By: TRBenj
Date Posted: May-01-2012 at 12:50pm
|
If it is in fact dripping after shut down, you'll have an easier time restarting it if you open the throttle up all the way rather than pumping it. That will allow the motor to ingest the most air possible without introducing (more) excess fuel. There has been a lot of issues with new needle/seat and fuel bowl castings as of late, it seems... you are not alone! ------------- |
Posted By: rtsuggs
Date Posted: May-01-2012 at 3:23pm
|
Yea I put new needle and seats in even after the rebuild ,I thought I might have got a bad needle or seat. It didn t fix the problem of the rear bowl flooding till I bent the float down a little. I did the same to the front bowl last night. Maybe that will fix the problem. Thanks ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=5143" rel="nofollow - 78 nautique 78 ski nautique SOLD 85 ski nautique |
Posted By: 8122pbrainard
Date Posted: May-01-2012 at 3:35pm
|
Has anyone ever used Daytona Parts rebuild kits for these carbs? I ask since I had to go to them to get the kits for my YH's. They have their own design for the needle and seat that they say is supplied with every kit they put together. The design I thought was very unique and from an engineering standpoint very logical. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: pdhowell
Date Posted: May-03-2012 at 5:21am
|
If the float adjustment does not work, you might look at a fuel pressure regulator. I had the same problem on my 1988 PCM 351. A fuel pressure regulator solved the problem. I believe I used this one: http://www.summitracing.com/parts/HLY-12-804/ I cannot remember, but that I had to cut or replace the hard fuel line with a marine flexible line, but it was an easy install. It goes between the fuel pump and the carburetor. I was concerned about this being automotive unit , and called the Holley tech folks. They said that this was the same part they used in marine engines. Maybe useful |
Posted By: rtsuggs
Date Posted: May-04-2012 at 1:16am
|
Thanks I may have to try that. ------------- http://www.correctcraftfan.com/diaries/details.asp?ID=5143" rel="nofollow - 78 nautique 78 ski nautique SOLD 85 ski nautique |
Posted By: snipe
Date Posted: May-04-2012 at 3:37pm
|
Dave, What kind of flexible hose did you use between the fuel pump and carb? ------------- /diaries/details.asp?ID=4810" rel="nofollow - 80 Ski Nautique |
Posted By: pdhowell
Date Posted: May-04-2012 at 4:44pm
|
Snipe, you got me thinking about this this morning. I replaced the hard line from the pump to the carburetor with a flexible, rubber fuel line made for marine use. I bought it at a local CC dealer. It was very similar to this: http://www.jamestowndistributors.com/userportal/show_product.do?pid=576&familyName=Fuel+Feed+and+Vent+Hose+Type+A1. That is about the same price I paid per foo, and I think used 1/4 inch line. Marine fuel line has more fabric and seemed much thicker than automotive fuel hose. For connections, I used 1/4 npt barbed nipples screwed into the ports and double hose clamped all the hose/nipple connections. This hose made taking the carb off much easier, since I wasn't always struggling with the threaded fittings on the hard fuel line. I rebuilt carbs, bought a new carb, reset floats, everything, and the carb always dripped gas at shutdown. This regulator solved everything for me. Watch the arrows on the pressure regulator to make sure the gas flows in the right direction. You can adjust your the fuel pressure but the factory setting was good. Make sure you get a regulator for carbs (1-4 psi), most are now high pressure for fuel injection. Hope this helps, Dave |
Posted By: 8122pbrainard
Date Posted: May-04-2012 at 5:18pm
Dave, Look closely at the description. You used a fuel rated hose designed for the feed side (low pressure) of the fuel pump. The high pressure side from the pump to the carb per USCG regs must be hard piped with flare fittings or a USCG approved hose assembly. You just downgraded your boat to being dangerous. Go back to struggling before you have a problem. BTW, http://www.jamestowndistributors.com/userportal/show_product.do?pid=576&familyName=Fuel+Feed+and+Vent+Hose+Type+A1." rel="nofollow - here's a proper link to the rubber low pressure fuel line And here's one to the http://www.summitracing.com/parts/HLY-12-804/" rel="nofollow - fuel pressure regulator What pressure were you feeding the carb before you installed the regulator? I ask because somethings wrong. We have hundreds if not more members who haven't needed the regulator? ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
pdhowell wrote:Posted By: TRBenj
Date Posted: May-04-2012 at 5:27pm
|
Actually Pete, I believe Joe schooled us last time- a barbed fitting plus USCG A1 flexible line and appropriate clamps is ok on the pressure side of the pump. I cant find the verbage requiring the barb, but I could have sworn I read that before. Info on the hose type here: http://www.uscgboating.org/regulations/boatbuilder_s_handbook/fuel_standards_partl.aspx" rel="nofollow - USCG regs
------------- |
Posted By: pdhowell
Date Posted: May-04-2012 at 5:43pm
|
Pete, Good thoughts and I will look at this again. I just rebuilt the motor (from too fast/too much pouring winterizing oil through the carb and bending the connecting rod) Ahhhhhh!!!. The inboard marine shop that did the work nit picked about several items in my engine compartment, mostly insufficiently unsecured wires, none safety related, but did not mention this. I bought my hose from a Correct Craft dealer who said they were using the flexible fuel hose on their boats. I checked the procedure with Holley, their marine guy, who insisted that I double clamp the hose/nipple connections. Now you have me thinking, what would be pressure be on the pump side of the regulator? Since there is a provision for checking this on a vacuum gauge (I am wondering how accurate.....) I will check this. I am thinking that it can't be too high, because the fuel pump came from Ski Dim, for the 1988 351W and most of those engines never had regulators. The fuel line is heavy, and the connections are secure. Still, if you had a fire, a hard line would seem to be better. Thanks again for pointing this out. Dave |
Posted By: 8122pbrainard
Date Posted: May-04-2012 at 6:29pm
Tim, I must have missed Joe's "schooling"!  I just got home and looked up A-1 fuel hose and yes, it does look like it can be used. "A1 and A2 hose must be used from the fuel pump to the carburetor, the high-pressure side on the marine engine. A1 hose must be used from the fuel vent, and from the tank to the engine intake. A1 and A2 hose receives its rating based on its construction. The rules stipulate that you use A1 or A2 in places of high pressure, where more than five ounces of fuel can escape in 2.5 minutes when the hose has suffered a major cut or disconnection while the engine is running. This also applies when the engine does not run but springs a leak, and also with a full tank of gas." I too could not find anything on the termination but I'll look. Dave, Sorry about some possible misinformation. It looks like you're good with the hose. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: pdhowell
Date Posted: May-04-2012 at 7:34pm
|
This online place is great. I have learned an incredible amount of information, and finally have a chance to give back something that may be useful. I needed a rebuild of my engine because when I was winterizing, I was poured Sea Breeze (liquid, not spray) through through the carb of the cranking engine in an effort to distribute the oil to all cylinders. I ended up withe oil in the lowest cylinder hydrolocking and bending the connecting rod. I thought I was being careful but the oil flowed down the intake manifold, through the intake valve and into the lowest cylinder, causing the connecting rod to bend and the piston to hit the crankshaft. (The clearance between the descending piston and throws of the crank had decreased enough for this to happen.) I had to replace the piston, rings, rod, bearing, but did not requires any bore work. I had a highly recommended marine engine shop (Berger Machine and Marine, Hagerstown. MD), tear it down and was curious what they found in a 24 year old engine with about 900 hours. To me, it was very encouraging: virtually no cam wear (I have been careful about the oil) , no significant wear/burning on the valves to requires head machining (the carb is jetted to be slightly rich), very little bore wear (I had suggested re-ringing if at all indicated), new ring gear because of some substantial teeth wear/chipping from starter, new cap, rotor and all gaskets. Also all dash instruments were erratic. Total cost: Labor $1834, parts $289. They did not work on the electrical issues, but checked oil pressure/temp with shop gauges. The gauges went wonky on me last summer, so more under dash work this spring, probably cleaning up grounds. The carb dripping issue was solved before all this happened. Hope this information might be useful to others, especially the part about pouring in the winterizing oil. Dave |
Posted By: pdhowell
Date Posted: May-04-2012 at 7:56pm
|
Pete, here is an edit to your question. I thought about your answer some more, added some more information, and then realize that I got off track with my answer. Pete, Rereading your note, you asked about why the need of the regulator. Short answer, I don't know, but after two professional rebuilds of the carb, one rebuild of my own, even more bending the tab of the float, and then finally a new carb, I still had my problem. I replaced the fuel pump, still had the problem. I tried insulating the copper line to keep it cool, and ran the blower constantly to keep cool air coming into the engine compartment. Hence the regulator. I still had the problem The only thing left was too much pressure pushing my needle off the seat at shutdown. I was skeptical because I had not seen anybody else talk about this on this forum. But I had an engine rebuild shop in my past, and had often had to put fuel pressure regulators on truck engines. I tried to remember, but was thinking that many rebuilds were Fords, and probably the Windsor 351 because that was a common truck engine. I will say that on my boat, I could not manage a very neat install. The regulator comes with a mounting plate, but the only place I could find to put it was on the plywood floor, not anyplace on the engine. I had to be careful that gas line hoses don't rub on the engine cover. It does not look very good, but is secure and easy to observe for any problems. Hope this helps, Dave Dave |
Posted By: 8122pbrainard
Date Posted: May-04-2012 at 8:05pm
|
Dave, Have we asked you for pictures yet?  We'd love them!I'm glad to hear the rebuild went great. ------------- /diaries/details.asp?ID=1622" rel="nofollow - 54 Atom /diaries/details.asp?ID=2179" rel="nofollow - 77 Tique 64 X55 Dunphy Keep it original, Pete < |
Posted By: pdhowell
Date Posted: May-04-2012 at 9:34pm
|
Ok, I will try and get some pictures. I am very proud of my boat, but it is far from original, and I know that is important to many her on this forum. The boat is a Dominique, was often beached on rocks, left in storage for several years, had the trans and engine locked up, in other words a real orphan. But it was cheap to buy and fun to fix up. Over time, about the only thing original is the hull, engine cover, and engine block. Has MSD ignition, 72c trans instead of the 71c trans, new shaft, prop, new interior pedestal seats, Fly High Monkey Bar, boom. It is a work boat with dings and scratches, certainly not a trailer queen, but a great boat, that is a blast to drive, pulls anything, and (to me), good to look at. Thanks for asking. Dave |
Posted By: BuffaloBFN
Date Posted: May-04-2012 at 11:00pm
|
My local Holley dealer has heard a rumor about marine pumps(recent) putting out too much pressure... Possible diaphram material change? ------------- http://correctcraftfan.com/diaries/details.asp?ID=2331&sort=&pagenum=12&yrstart=1986&yrend=1990" rel="nofollow - 1988 BFN-sold "It's a Livin' Thing...What a Terrible Thing to Lose" ELO |
Posted By: Bri892001
Date Posted: May-05-2012 at 12:02pm
| It would be cool to see. The Dominiques aren't too common on here. |