Wiring fuel sending unit
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=31430
Printed Date: May-07-2024 at 11:30pm
Topic: Wiring fuel sending unit
Posted By: Aclobyrick
Subject: Wiring fuel sending unit
Date Posted: September-03-2013 at 6:58pm
I'm in the process of restoring my 1981SN and am having problems with the fuel sending unit. I've drained the tank two times, removed and replaced the existing sending unit. When I turn on the ignition the gauge pops up to the empty point. While out of the tank, I moved the actuating arm up and the gauge registers as it should. Put it in the tank, properly, pointing in the proper direction, fill the tank with fuel and get the same results.  I have an aluminum, 31 gal. tank, 12" deep. Black wire attached to the top of the sending unit, gray or pink wire hooked to the clip of the sending unit. The sending unit is a Moeller electric sending unit, SKU#MOE 025722-10.1 as advertized on Wholesale Marine. A guess, could the sending unit be touching the bottom of the tank? I just thought of that! Any help would be appreciated.  ------------- Rick Allen, aclobyrick, Sacramento, CA |
Replies:
Posted By: Bri892001
Date Posted: September-03-2013 at 7:37pm
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Do you have any pictures of the installation? It should be wired something like this. The Green wire is just the ground for the stern light, the black is ground and the red/pink is the sender: 
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Posted By: Aclobyrick
Date Posted: September-03-2013 at 9:17pm
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Thanks for the info. The Pink was hooked to the ground sideclip and the ground was hooked to the sending side. Reversed the leads and tried it, still the same. ? I'm back tracing the wiring off the latest schematic I have which is 1984. ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: rapok4
Date Posted: September-03-2013 at 10:10pm
| Double check you have a good ground. Common problem is loose or missing ground. |
Posted By: Bri892001
Date Posted: September-04-2013 at 11:32am
Agree. With everything still installed, remove your pink wire, and touch it somewhere else on the metal ring that the black wire is attached too. This should peg your gauge to full. We'll see where we go from there. |
rapok4 wrote:Posted By: Aclobyrick
Date Posted: September-04-2013 at 4:13pm
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That works! Gauge pegs to beyond full, what next? ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Bri892001
Date Posted: September-04-2013 at 4:58pm
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Well, that confirms that your gauge is good, and that you have a good ground. Unfortunately, it means there is something wrong with the sender or the way it's installed. Is the the type with a float and a wire arm that kind of looks like a little toilet bowl float? |
Posted By: Bri892001
Date Posted: September-04-2013 at 5:04pm
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Have you had it in there at any point, and run the boat, aka using up fuel? Does the gauge move at all? |
Posted By: Aclobyrick
Date Posted: September-04-2013 at 5:41pm
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Had someone working on my boat. They removed the tank to clean it out. Have no idea as to weather the unit thats in it now is a new one or the original. When I got the boat back, it wasn't even wired. Long story with this guy. I've removed it and reinstalled it carefully two times. It even worked out of the tank. I moved the actuating arm up and it moved the fuel gauge up. Thats why I'm wondering if the arm is hitting the bottom of the tank keeping it from moving. I'm a GC with 40 yrs of experience so I know a little bit about what I'm doing. Can I pull the tank out carefully with the fuel in it and remove the sender again? How do I send you a picture on the Forum? ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Gary S
Date Posted: September-04-2013 at 5:48pm
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I had a simmier problem with that too. Turned out that the sender did not ground properly using that screw. It seems that the newer senders have a ground tab right on the sender body. I did that and all troubles went away. Get yourself a piece of wire,clip one end to a good ground and the other end to the sender body,you would be best just to hold it on there and try it and see if thats your problem.For some reason mine would not ground thru the sender mount screw but that was how it was wired before I took the tank out to clean. ------------- 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: Gary S
Date Posted: September-04-2013 at 5:50pm
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Now that I relook at the sender pic,isn't that phillips head screw on the far side,the ground??? ------------- 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: Hollywood
Date Posted: September-04-2013 at 5:55pm
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Gary, that's Brian's plastic tank I believe. The OP said "clip" so I believe he has the ground tab/prong an not using a mount screw anyway. My 88 has a tab, I don't recall the setup on the 80. ------------- |
Posted By: Bri892001
Date Posted: September-04-2013 at 6:03pm
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Yup, the OP said an aluminum tank, that's my plastic one. The Original Poster has to remove the tank to get the sender out? I had enough clearance with the tank in place, but a little bigger boat I guess. Wondering if the ground wire for the stern light is being mistaken for the actual ground wire. Without the actual ground also connected, the stern light ground would be a path to no where. To post a picture, don't use the "quick" reply box. Find the other Post Reply with the little diagonal blue arrow. Click on that one, and choose the icon for posting a pic. Will be easy from there. |
Posted By: Hollywood
Date Posted: September-04-2013 at 6:29pm
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31 gallons in an 81 seems awfully tight. So taking the pink and tapping it on the ground prong pegs full the gauge? This means the ground is good and it's a float arm problem. Does arm swing port or starboard? Might be able to angle the boat and lift the sender enough to unwedge it from the bottom. So if it swings to port park the boat port side low. Should the correct sender ever actually reach the bottom? ------------- |
Posted By: Aclobyrick
Date Posted: September-04-2013 at 6:56pm
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It's tight, but I have had it out. Did the picture come through? The boat is trailered, in my shop. The arm swings to the port side of the tank. The starboard side has a baffle in the tank to keep down sloshing. Don't know if the correct sender is in the tank. I could remove the screws and lift the sender up. I have about two to three inches of clearance at the stern. ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: rapok4
Date Posted: September-04-2013 at 6:59pm
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I just walked back outside and checked the tank in my '81. It is aluminum and 25 gallons. When I pulled the tank the ground wire was attached to the stern light but not to a ground?! 31 gallons of gas is over 200 pounds, I would not recommend moving it full. It sounds like it is your float. I have seen the actual float ball become so saturated over time they wont float anymore. No pics. |
Posted By: Hollywood
Date Posted: September-04-2013 at 7:08pm
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Ground wire is probably just daisy chained off the stern light. That's ok. ------------- |
Posted By: Aclobyrick
Date Posted: September-04-2013 at 7:22pm
I have a direct ground line coming to the rear of the boat which connects to the blower, stern light, and the sender. All good grounds. I'm thinking I will purchase a new sender and replace it. ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Bri892001
Date Posted: September-04-2013 at 7:33pm
From another thread:
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Posted By: 8122pbrainard
Date Posted: September-04-2013 at 8:13pm
As long as the ground is good to the engine block. I suggest getting the VOM out and checking to see if there is any resistance through the ground wire to the block. It should be near zero. Check all the connections. ------------- /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: ArtCozier
Date Posted: September-04-2013 at 9:06pm
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I haven'taken time to read all these posts, but I think you originally mentioned a gray and pink wire on the center post???? The gray doesn't belong there. That's the power to the stern light. And the green wire bonds (grounds) the fuel fill. Art ------------- "Art" |
Posted By: Aclobyrick
Date Posted: September-04-2013 at 10:21pm
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No gray wire connected, only the pink. Thanks ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Aclobyrick
Date Posted: September-04-2013 at 10:22pm
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Not the problem, Thanks ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: gun-driver
Date Posted: September-05-2013 at 12:26am
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In your first post you said it was a new sending unit that worked out of the tank when raising the arm. Later you said your not sure if its new. It should be easy to tell if its new or not(new-shiney Old-tarnished) My guess in this guessing game would be its the old one with a cork float that is saturated and doesn't float anymore. If it works out of the tank and its wired properly it has to be the float.(happened on my '85 changed float gauge works.) Siphon the gas out pull the tank(you will need to do this to replace it anyway)and see if it's the old cork float check it out of the tank again and go from there. |
Posted By: Aclobyrick
Date Posted: September-05-2013 at 1:56pm
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Best news I've had yet. Out of the tank it looks new, not tarnished. The float is a black substance, doesn't look like cork. It looks exactly like the picture I posted which was from Wholesale Marine supply. That's why I'm buying a new one and replacing it as you said. How's that old saying go, The third time is a charm! Let's hope so? Thanks again! ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Bri892001
Date Posted: September-05-2013 at 2:38pm
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One more time: So, out of the tank, with the wiring connected, the one you have works totally fine? Just wondering if the tank itself is picking up stray positive current from somewhere... |
Posted By: Hollywood
Date Posted: September-05-2013 at 2:41pm
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Brian wouldn't that peg the gauge full? Could just be a defective float. Put it in a gas can. ------------- |
Posted By: Aclobyrick
Date Posted: September-05-2013 at 2:49pm
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When I get it out I will test the float to see if it works. Thanks guys! ------------- Rick Allen, aclobyrick, Sacramento, CA |
Posted By: Hollywood
Date Posted: September-06-2013 at 11:29am
So for anyone following this thread or has found it as a search result, the problem was the sender arm was stuck against the bottom of the tank. He decided to make a separate thread explaining this ( ) but after bending it up a little everything fine works fine. ------------- |
Posted By: ArtCozier
Date Posted: September-06-2013 at 11:34am
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Thanks for letting us know. This has bugged me since I first saw the post. Art ------------- "Art" |
Posted By: Bri892001
Date Posted: September-06-2013 at 12:03pm
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I saw the other post too. I'm a little less than fully satisfied, since I would think that a float arm that is too long would prevent the gauge from reading all the way empty (since it hits the bottom before it get the full downward swing), and the first post said it pegs to empty. But, I suppose if just jams in there on the install it could happen. |
Posted By: ArtCozier
Date Posted: September-06-2013 at 12:17pm
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I guess that if it was just on the borderline of against the stop and jamming against the bottom and the fuel sloshed into it from the port side, it might get driven harder into the bottom. Or, if he took the tank off its mounts to get it out, installed the unit, then bolted the tank back down, it could have pushed the tank bottom hard against the arm. I preferred the earlier senders that had the oval-shaped float bent at 90 degrees to the arm. They laid flatter against the surface of the fuel, therefore I think yielded better accuracy. Art ------------- "Art" |