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What is wrong with this waterpump?

XJJack said:
I do not have the ground on the head, as that is only to ground the body. I have a good ground on the block as the starter works fine and a seporate ground to the body for everything else.
Click to expand...

Do the ground from the head to the body. It causes all kinds of problems. Remember you are also running an aluminum head. Dissimilar metals make for a galvanic reaction. The ground to the body is really most needed by the computer. Relying on the main ground has a bad habit of causing tons of problems with the computer. If you don't have a good ground to the body, you will get current flowing though you coolant into your radiator and from there to ground. What you see is a textbook example of why to ground the engine to the body.

I had a chevy van that the mechanic left the ground strap off and it caused a failure of the babbit bearings in the tranny.
 
Yes, I understand that if the motor is not grounded there will be problems as it will find a path through other things But the grounds are there just have a different path intead of the stock path of batt to motor then body I have bat to motor and batt to body. This does the same thing.
 
Ok, don't believe me. I am an electrical engineer with 35 years of experience, Replace your pump and the same thing will happen again.

Don't you think is is odd that I called a missing ground and that is what you have? Do you think the manufacturer spent the money to put it there just for looks?
 
I'll agree with the simple corrosion part. That impeller is probably a cast piece and may have cavitated from water saturation. There was probably some tiny air pockets in the cast metal and the corrosion allowed the cavitation. You can kinda see a "swirl" to the metal where the cast looks denser.

I'd definitely send the pics to Hesco and see what they have to say. They might just send you a replacement..........:dunno:
 
If you look cloce in the block it looks like a circular pattern on the left..

I have used tap water with a aluminum pump and heads never had anything look like that..

Dont reuse it.......................
 
YELLAHEEP said:
I'll agree with the simple corrosion part. That impeller is probably a cast piece and may have cavitated from water saturation. There was probably some tiny air pockets in the cast metal and the corrosion allowed the cavitation. You can kinda see a "swirl" to the metal where the cast looks denser.

I'd definitely send the pics to Hesco and see what they have to say. They might just send you a replacement..........:dunno:
Click to expand...

Sorry to dought you, just asking the questions and trying alisit as many posablilties. Thank you for all the advice. I will add the extra ground and try the distilled water, but I guess I wont know if it makes a difference for a few years down the road.
 
It really isn't so much the ground from the head to the block as it is the whole engine to the body. There are only a couple of small body based grounds running from the wiring harness to the body. All the current from the headlights, tail lights, blower motor, etc. have to run from the body back to the battery. Also when the engine is cranking, there is a significant voltage drop across the cable from the block to the battery. This puts several volts of low source impedance power between the block and the body. The computer uses sensors that are referenced to the body and the voltage offset can yield unreliable readings.

Many of the supposedly oil pressure posts on here are remedied with a good ground strap. The water temp gauge on the Renix units suffers the same problem.
 
I would talk to Hesco. I am leaning toward a gorund type issue or maybe tap water. It looks like an elctrolosis issue and could be worse because of the tap water. I do not believe tap water alone would have done this, but I would talk to Hesco they are very knowledgeable. Prestone green is fine to run in an aluminum motor. I run an aluminum radiator, and a hesco pump and use the 50/50 premix from Prestone.
 
that's cavitation pitting. Not from the coolant being corrosive. It has to be the impeller design.

Notice how clean the pits are. Bright and scoured.

The cavitation bubbles implode like tiny bombs and blast little bits of metal from the surface. Any roughness in the finish can start the erosion process, which only worsens itself.

You should see this same effect on a boat prop, in a corrosive salt bath. Same pits, but with a crust of corrosion salts.
 
Something had to create the cavitation in the first place. I'm thinking it started to corode and then starting to cavitate. Now it is just going to get worse. I would put new grounds on , a new hesco pump, flush the cooling system, and put new premix in and don't worry about it for at least another two years. Maybe Hesco would even give you a deal on a new pump.
 
replace pump add gounds and go to honda and get thier coolant its premixed it is in my xj for the last 2 years and no problems my 2 cents
good luck
 
Get a free replacement from Hesco, use distilled water (just to be paranoid), and verify your grounds. If Hesco wouldn't replace it for free, I sure wouldn't buy another one. Good luck on their aluminum head!
 
I wouldn't be so quick to blame Hesco. I'm sure there are a ton of their pumps out there without any problems, mine included. I would see what they say before you make any blame. Why should they have to fix someones problem if a ground caused it. I had to return a water neck to them because it was machined incorrectly, and they had no problem sending me a new one no questions asked.
 
don't post here much but here's my two cents... looks like you may have a bad/dislodged wp bearing; it may spin well and fine but spin it in your hand to make sure it stays in plane. had a similar issue with mine- spun fine but had a tilt to it and nailed a couple of the little tangs inside the engine as well as the wp itself. as for electrolysis, that may be the case but that generally affects stationary parts i.e water outlet necks... etc. the general idea is that coolant w/ distilled water conducts electricity very poorly (that's a good thing) when you introduce tap water (which conducts electricty very well) it will ground out on any metal surface (primarily steel/iron) causing the pitting on that surface... long story short the damage to the water pump, if it was electrolysis, would be a bit more evenly dispersed on the impeller. annnnd as for coolants as long as you don't mix colors you are pretty much ok with whatever brand you want - all coolants for the most part meet the same sae requirements; personally I would use the green though, as long as the coolant isn't say more then 8 years old or so. dexcool (red stuff) was originaly developed for when chevy started to swap to aluminum blocks and or radiators and was designed for such... buttttt now that just about everything has a aluminum radiators (cores at least) all of the green coolant (peak, sierra, whatever) is fine for aluminum engine components. oh yeah about the pump, make hesco/ (whoever built the motor if that was the case) warranty that sucker or just buy a new one. if that really was caused by electrolisys then that is some super crappy aluminum on that impeller. oh yeah and sorry for the rant everyone. cheers
 
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