Blower, bilge and trim all stopped working at once

[jimrockireland]

I have a 1983 Wellcraft 196 Sunhatch with a MCM228R engine. I did some engine work (removal and re-installing) and got everything back together but the blower, bilge pump and trim pump doesn't work. I can't imagine what they have in common. To test the trim pump I would have to cut some wires to isolate the pump from the switch , but I'm reluctant to do this since it seems to be more than just the pump. I looked for disconnected wires under the console switches, but really see nothing disconnected. All the console fuses look good. Any ideas? Is there some additional fuses somewhere else?

 

[indybleck]

Check the wire harness connector on the engine

 

[alldodge]

I have a 1983 Wellcraft 196 Sunhatch with a MCM228R engine. I did some engine work (removal and re-installing) and got everything back together but the blower, bilge pump and trim pump doesn't work. I can't imagine what they have in common. To test the trim pump I would have to cut some wires to isolate the pump from the switch , but I'm reluctant to do this since it seems to be more than just the pump. I looked for disconnected wires under the console switches, but really see nothing disconnected. All the console fuses look good. Any ideas? Is there some additional fuses somewhere else?

In most cases the Trim pump comes from the starter post or 90 amp fuse on the starter post. My guess is your bilge and blower comes from the same feed.

The ground should be in the same area coming from the trim pump

 

[jimrockireland]

I think the engine harness is OK. The boat starts up fine and the wires that go to the trim pump appear to come from a separate harness. Tomorrow I'll see if I can trace the wiring from the starter motor and see if I can find the 90 amp fuse.

 

[alldodge]

The 90 amp fuse is a square block, doesn't really look like a fuse, but if it blows nothing works

 

[jimrockireland]

Are you saying the engine won't start if the 90 amp fuse is open? I can get the engine going and I did measure 12V at the trim pump connection.

 

[alldodge]

Yes I did say that, but my thought is the wire from the starter to the trim pump is either not connected, or the 20 amp fuse on the trim pump is the issue. You mentioned doing some maintenance and then the stuff stopped working. Don't know what maintenance your doing, just stating where the connection to the trim pump comes from

 

[fhhuber]

You have one or more CONNECTORS that is effectively unplugged. maybe the boot makes it look plugged in.

The harness itself can be fine and all look OK, but a connector have quit making electrical contact. (or not have gotten fully plugged together)

Just go over all the connections you dealt with... and the ones you thought you didn't bother.

 

[jimrockireland]

The trim pump harness is a boot enclosing 3 wires (red-green-blue). The female connector on the pump has 2 connecters as in a normal plug and a third connector in the position a GND would be in a standard electrical outlet. I believe these wires come from the trim switches on the shift lever. I could not measure 12V at the trim switches on the shift lever which I thought to be not right. Should I have 12V at this switch?

 

[Grandad]

There may be a common point that's giving you trouble, but I would choose the easiest of the 3 affected systems to troubleshoot. When you find out why, for instance, the blower doesn't work, you'll have likely found the reason why none of them work. Don't overlook verifying the negative connections. There may be a common point for all of these items. Remember too that a meter, particularly a cheap digital one, might show full voltage at a point that could actually have low voltage when a substantial load is applied to a circuit with a weak connection. Always use a "known" good positive or negative point as a reference when checking voltage at suspect connections. - Grandad

 

[jimrockireland]

Thanks for the suggestion. I took Sunday off as a family/church day but will get back to debugging Monday. I like the suggestion to trace back the blower motor (only 2 connections there). If I can't trace that back I can trace the bilge pump. I have 3 connections on that one.

 

[gm280]

Check any and all ground wires and lugs. Grounds are needed for every circuit and most often ignored. JMHO

 

[jimrockireland]

Thanks for all the suggestions. By measuring some voltages at the trim pump I discovered I hooked up 2 GND wires to the wrong terminals. I had a GND wire going to the battery and one going to the trim pump. The GND to the trim pump was not really a GND it was a wire that was supposed to be the GND feed for the bilge pump and blowe and should have connected to the batteryr. The trim pump GND comes from the GND terminal on the engine block. All in all everything is back working. One anomaly is I broke a fuse that was coming from the trim pump +12V and the wire exited through a whole in the transom. I'm not 100% sure what this goes to but I suspect it powers the trim sender since my trim guage is presently disconnected.

 

[gm280]

Thanks for all the suggestions. By measuring some voltages at the trim pump I discovered I hooked up 2 GND wires to the wrong terminals. I had a GND wire going to the battery and one going to the trim pump. The GND to the trim pump was not really a GND it was a wire that was supposed to be the GND feed for the bilge pump and blowe and should have connected to the batteryr. The trim pump GND comes from the GND terminal on the engine block. All in all everything is back working. One anomaly is I broke a fuse that was coming from the trim pump +12V and the wire exited through a whole in the transom. I'm not 100% sure what this goes to but I suspect it powers the trim sender since my trim guage is presently disconnected.

Well glad you found your problem. We all make mistakes and cause ourselves more work some times then we really need. But when you find your problem, it all seems good again in the world. Happy and safe boating. :thumb:

 

[alldodge]

One anomaly is I broke a fuse that was coming from the trim pump +12V and the wire exited through a whole in the transom. I'm not 100% sure what this goes to but I suspect it powers the trim sender since my trim gauge is presently disconnected.

This is the trim limit switch. The drawing below is simplistic but the Blue/White and Purple/White at the pump go to those wires. It also doesn't matter which one goes to which