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Discussion Starter · #21 ·
There might have been.

It was stated in reply #6 that the water pump draws 6-10 Amps

With the pump positive going through a 20A fuse and then to the battery positive post and then the negative wire off of the pump going to the same battery ground, the fuse never blows.

If then the pumps positive wire were to be wired through a relay and the activation coil is wired with one side going through a 5A fuse and then this connected to the battery positive post, then when the activation coils other wire is then touched to the same battery ground, then the relay will click, then power get's pulled through the 20A fuse to the pump and with it grounded will allow the pump to pump or spin.

If when touching the activations wire to ground causes the 5A fuse to blow, then there is a short or too low of a resistance in the activation coil, If the 20A fuse were to blow, then the relay has to be connecting the supply of power to a ground and the only ground would be on the one end of the coils activation wire.

If a fuse blows very quickly and pops hard, to me this indicates a real good direct short. If it glows a bit and then blows, on let's say a 20A fuse, then the current draw might actually be 30A. Remember that a 20A fuse willpass 20A all day long and probably pass 25A also all day but then if asked to pass 30A it doesn't happen right away but there is a time delay and if the current is increased to 35A, the time delay s shorter and then if asked to pass 100A, then in a split second it pops.

Jim
So the fuse definitely “pops” hard every time. I’ll try out the 20amp/5amp relay activation method you described above this weekend.

Appreciate the help
 

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Discussion Starter · #22 ·
Damn, sorry that didn't work out. As Custom Jim mentioned, the relay may well be the culprit. The guys talking about a short in the body of the pump itself made sense too... If the wiring in the pump is shorting to ground, then the ungrounded second battery works because it's direct-wired and not grounded touching the water inlets on the front of the engine, grounding that way through the body and block grounds then to the negative terminal on the main batt. Good suggestion above there... May check that out too... Can't hurt and maybe the pump motor or wiring is roached. Check that relay though ... Check ohms resistance from + to ground on body of pump and then from - to body of pump... See if there's a short to ground. It should be an isolated circuit for the pump motor and not use the body for ground ... That would at least tell you if you have an internal short in the pump itself.
Im leaning towards a short in the motor as well and it makes sense how you described it. Hopefully the new pump motor will be here sooner than October.
I’ll test to see if there’s a short to ground as well to verify.

Thanks for all the help and I appreciate you working through this with me.
 

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I would have to agree also that there is a direct short somewhere if the fuse blows immediately. You bypassed the relay etc to another battery with no problems so that should rule out the pump being bad. Checking the relay was mentioned above and I am suspect of that also. Try another relay of possible and triple check the relay wiring. If it is wired wrong it could cause a direct short to ground. Remember when looking at a relay diagram reference the numbers on the diagram, the diagrams can be confusing or backwards depending on if you are looking at the relay or the socket. Good luck hope you figure it out soon
 

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Discussion Starter · #27 ·
Reis55
Any update on this water pump issue? I'm really curious as to your findings and cure.
Spoke with the manufacturer and they seem to think it’s an internal short as well. Gonna pull the pump this weekend and send it to them for rebuild/replacement it should still be under warranty.

Ordered a spare pump motor when I started this thread and ended up receiving it yesterday. I’ll swap in the spare when I pull the bad pump. Keeping my fingers crossed it’ll all work out.

I’ll be sure to update as I make progress.
 

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It’ll blow a fuse as soon as the ignition is in the “on”position.

Tested the EWP motor with a with a 20 amp fuse on a spare battery and it works as it should.
If the motor had an issue then it would have blown the fuse when wired to your spare battery.

"Possibly" and intermittent issue BUT you have to look at what was changed. Now it's going through a relay wired to the ignition ?.

Jim
 

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I thought that too at first but then thought about it more and decided it may or may not, depending on where the short is. If the short was to ground (the body of the pump) then it would only blow the fuse for the main battery as the spare battery was not grounded to the body of the pump as connected at the front of the engine (grounded by the block), the spare battery was pos/neg to motor only so no internal circuit completion, only direct from and to the battery only.
 

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One final comment on the separate battery test issue. It ran fine hooked up that way. Do it again but this time after you hook up the pump + and - and get it running, take a jumper cable from the remote battery negative to the car frame. My bet is it'll blow the fuse instantly .
 

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take a jumper cable from the remote battery negative to the car frame
@Bob's 65 Post that's exactly right! The short is internal to the pump to actual body ground, not shorted to the motor of the pump itself. Hope we're right and the new pump fixes it!! Fingers crossed :)
 

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Discussion Starter · #32 ·
One final comment on the separate battery test issue. It ran fine hooked up that way. Do it again but this time after you hook up the pump + and - and get it running, take a jumper cable from the remote battery negative to the car frame. My bet is it'll blow the fuse instantly .
Update for everyone interested.
Did Bob’s 65 test and the fuse blew the fuse immediately. Pretty sure at this point it’s an internal short.
 

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Discussion Starter · #34 ·
Drained the coolant and took the motor off the pump housing. Gonna replace it tomorrow and hope for the best. Did notice the old pump doesn’t spin as freely as the replacement. Some sort of friction somewhere, you can feel it when you turn it. I’ll get the new pump on tomorrow and post the results.

After contacting the tech department/manufacturer I received a ticket number to send it in. Hoping it’ll be fixed under warranty and I’ll have a good spare.
 

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Discussion Starter · #38 ·
Here’s what I’m workin with…

Motor vehicle Automotive tire Hood Automotive design Vehicle
Hood Automotive tire Motor vehicle Bumper Automotive design

Fenders and front end are on now. I’ll post pics of the compete front end tomorrow once I put the new pump in.
 
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