Water pumps

[brbuilder]

Anyone using the GMB 125-1420P water pump?
Per the info on Rock Auto the 125-1420P has a high performance impeller that increases pump pressure by 300%. I ordered the 125-1420P from Rock Auto. It came in the manufacturer’s box with a part number sticker of 125-1420P on the box. Inside was the pump in a sealed plastic bag with a part number sticker of 125-1420AL on the bag. So I called GMB customer service and was told there is no difference between the 125-1420P and the 125-1420AL. Sent it back to Rock Auto and had them send another 125-1420P pump. This one came in the same manufacturer’s box with the part number sticker of 125-1420P on the box. Inside was the pump in a sealed plastic bag but no part number sticker on the bag. Both pumps were aluminum bodies with 8 blade bent steel impellers. Wondering what makes the 125-1420P high performance and cost $13 more than the 125-1420AL on Rock Auto. If there’s no difference then anyone considering these pumps should just purchase the 125-1420AL and save $13.

 

[nvrstuk]

Could you post up a pic?

300% better than what?

 

[Broncobowsher]

3X more pressure to make blowing up heater cores even easier. So that is the sales pitch?

 

[tirewater]

Anyone using the GMB 125-1420P water pump?
Per the info on Rock Auto the 125-1420P has a high performance impeller that increases pump pressure by 300%. I ordered the 125-1420P from Rock Auto. It came in the manufacturer’s box with a part number sticker of 125-1420P on the box. Inside was the pump in a sealed plastic bag with a part number sticker of 125-1420AL on the bag. So I called GMB customer service and was told there is no difference between the 125-1420P and the 125-1420AL. Sent it back to Rock Auto and had them send another 125-1420P pump. This one came in the same manufacturer’s box with the part number sticker of 125-1420P on the box. Inside was the pump in a sealed plastic bag but no part number sticker on the bag. Both pumps were aluminum bodies with 8 blade bent steel impellers. Wondering what makes the 125-1420P high performance and cost $13 more than the 125-1420AL on Rock Auto. If there’s no difference then anyone considering these pumps should just purchase the 125-1420AL and save $13.

Interesting, Summit lists the two pumps as well. The 'high performance' version has a number of reviews.

Visually, the GMB appears to be higher quality than the airtex water pumps I had in the past. I wasn't thrilled about the water ports only having 'half' lips on them. I had some seapage problems issues with the large one which require extra tightening with a small wrench rather than screwdriver.

 

[bronconut73]

My Explorer Serp Flowkooler wp from WH has what looked like a billet aluminum impeller. Very fancy. I think the impeller was even a candy purple color, lol. The cavities in the pump housing were very precise and looked cnc cut. Impressive looking.
And impressive performance....

My previous pump prior to the Explorer Serp swap was a Brassworks wp; as I understand it Brassworks and Flowkooler were related. Bought that Brassworks pump in the early 90's I think. Excellent casting and cavities like the Flowkooler but had a pretty ordinary impeller in it.

This new Explorer Flowkooler wp has apparently solved a long time overheating issue so I like the fancy impeller, lol.
The Explorer fan is helping that cause as well.

This latest Flowkooler is the first wp I have seen like it.
Definitely an upgrade over a typical casting and impeller.
Wasn't too expensive as I recall either.

 

[904Bronco]

My 1st experience with this brand pump was not good, front bearing/seal let go on my drive home. After just buying the Bronco, Owner stated it was two years old?

Yes found it on Summit, Overseas manufacturer.

I don't buy things like this from online or warehouse stores any more... When they fail under warranty it is a pain to get it replaced. I would suggest a local distributor, nationally know auto parts chain, new part, best quality that you can afford. And of course, good cooling system maintenance.

 

[DirtDonk]

I used a GMB standard replacement pump with good luck, but that was with a pump bought about 40 years ago and was, if I remember, made in Japan. It was also a daily driver at the time so no sitting idle for extended periods, and likely a better quality product back then.

Brassworks and Flowkooler are indeed related/same companies. My first FlowKooler was a GMB core with their (Flow Kooler's) 1st generation modified impeller.
The current models (and for at least the last 10 years or so) use their own design custom impellers like in bronconut's example.
More flow, less parasitic pumping loss (horsepower) and less chance of cavitation even at high rpm levels.
It's pretty trick stuff.

But to the OP, I have no idea what the differences are supposed to be either, but anything is possible. From the customer service tech having the wrong info, to the company having had two different pumps at one point, but now making them all the same and slowly getting rid of the part number. But not before they make a little extra money during the transition. I hate to think that's at play here, but I would not put it past anyone.
Or a combination of things, including the company being bought out, or even the distributors buying new brands and substituting them into GMB boxes. Would not be the first time something like that was going on behind he scenes.

You didn't happen to take pictures through the plastic bags by any chance, did you? Be interesting to see if there was any visual difference at all.

Paul

 

[brbuilder]

I have pictures of both pumps but not currently set up to post them. Both pumps look identical including the impellers. Took the back plates off for the pictures.

 

[DirtDonk]

If you think it'll add to the conversation, I can post them up for you.
Just e-mail them to my paulb@wildhorses4x4.com address and I'll throw them up for you.

Paul

 

[brbuilder]

Sent you 2 emails with the pictures.

 

[brbuilder]

It appears from internet pics that some water pumps have a 5 or 6 blade bent steel impeller. The 125-1420AL and 125-1420P pumps I received both had 8 blade bent steel impellers. Maybe that is the difference from the standard 125-1420 model. But I still don’t know what the difference is between the AL and P models.

Edit:
Checked the info on Rock Auto and the standard 125-1420 model water pump has an 8 vane impeller.

 

[DirtDonk]

Got 'em, thanks.

Here's the supposed AL pump:



And here's the supposed P pump:



Paul

 

[DirtDonk]

Sounds like they're transitioning over to the P pump for all units. As a running change, they're still offering the AL, but some of them already have the P style impeller.
So while supplies last, so to speak, anyone ordering an AL pump might get an old one, or might get a better deal on the higher performance model.

Long shot probably, but at least one possibility anyway.

Paul

 

[rpmgarage22]

Increasing the pressure from a water pump is a negative, in many ways, especially for our "stock or mildly altered" Early Broncos:
1) Increased pressure on a liquid does the same thing as increasing the pressure on a gas...it generates HEAT. You are working with an impeller, not a propeller. So, you are inputting heat into the "coolant" that you try so hard to "cool" while in your radiator. Ever put your hand on the "cooling fins" of an air compressor pump? Bet you won't leave it on there long. Exact same thing happens with these water pumps.
It's not a gimmick...they do increase pressure. But, that doesn't mean it's a good thing.
2) Increased pressure, as alluded to by another comment, can "find the weak spot" for you for any point downline of the multiplied pressure. Guess what kind of things are downline? The heater core, the heater hoses, the return line, and the head gaskets. How much you wanna bet your weak spot won't be the easy one...the return line?
3) Increased pressure from the impeller=more "stress" on the impeller shaft. The impeller shaft is connected to your engine fan (if mechanical fan, anyway). This relies on your fan being in perfect balance. Guess what? It's likely not... It will be in tolerance...but not in balance. This means that your high pressure pump will not live as long of life as your stock replacement.

Some say the answer is a higher VOLUME pump. But, that is another hocus pocus. How is the higher VOLUME generated? By a combination of a larger bore AND higher PRESSURE. We already talked about the pressure thing.

But, what about the VOLUME? Truthfully, you cannot increase VOLUME downstream of the water pump (generally speaking) anyway. To do so, you would have to bore the water gallies in the heads, increase the hose inner diameter, increase the port diameters, use a larger tube in the heater core, and so on and so on.

Now, there ARE engines where one (or both) of these products benefit: race engines or engines that certainly aren't described as "stock to mildly modified".

My $0.02 for the day...

 

[DirtDonk]

I think you're wrong on pretty much every count.
The higher pressure and volume are gained by making the impellers more efficient. The whole genre came from racing where every single horsepower counts.
The fact that it helps cool better was a nice bonus. Especially at lower engine speeds where sometimes a lack of water pressure is a negative because of the design, shape and casting surface quality of the water jacket of any given block.
Avoiding, or at least reducing hot spots that would otherwise cause steam pockets is a fantastic trade-off from any added heat that a higher pressure impeller design might impart.
I just don't think it's a thing.

Any added heat from the process is way less than the capacity of the radiator to rid the system of heat. It's minuscule compared to the heat generated, and evacuated by the engine.
If a given cooling system can't dissipate some small amount of added heat, it was borderline anyway.
If the same system can't keep from leaking with just a few extra pounds of liquid pressure in it, it was borderline anyway. And likely would have leaked just from higher ambient pressures from overheated coolant, should such a condition arise.
In both situations it simply proves that the existing cooling system was borderline defective.

And all of the high-volume water pumps in my experience have lasted longer, and in some cases, way longer than the standard water pumps used on the same engines.
And if not, just take advantage of the lifetime-warranty provide. Just like the regular pumps offer.
Nobody wants to change a pump again even if it's free for the new part. But in my experience at least, they always lasted longer.

I can't say for the different GMB versions, of course. But the FlowKooler, Moroso, Edelbrock and Steward water pumps I've used (and sold) have all been solid, high quality and long lasting products.

Paul

 

[toddz69]

My 1st experience with this brand pump was not good, front bearing/seal let go on my drive home. After just buying the Bronco, Owner stated it was two years old?

Yes found it on Summit, Overseas manufacturer.

I don't buy things like this from online or warehouse stores any more... When they fail under warranty it is a pain to get it replaced. I would suggest a local distributor, nationally know auto parts chain, new part, best quality that you can afford. And of course, good cooling system maintenance.

That's a pretty crusty pump for only being 2 years old!

Todd Z.

 

[904Bronco]

That's a pretty crusty pump for only being 2 years old!

Todd Z.

Same thoughts, no paperwork to back it up... It did not have the best of care, parked outside with windows left open... Plenty of PO stories with this one and some holes you just cannot figure out why they were there? I checked the pump, fluids and belts before driving home. Surprised it went south... Inside the pump was clean.

 

[rdullery76]

Any chance the "AL" model is aluminum, and the "P" model is pot metal?

 

[savage]

Got 'em, thanks.

Here's the supposed AL pump:

View attachment 496154 View attachment 496155

And here's the supposed P pump:

View attachment 496156 View attachment 496157

Paul

I know my eye's are getting old and don't see as good;D, but what is the difference between the two pumps ? I count 8 blades on both, and blade thickness looks the same.

 

[rpmgarage22]

Any chance the "AL" model is aluminum, and the "P" model is pot metal?

The "AL" does stand for aluminum. However, at least the last two "generations" of the "P" are also aluminum.