Recommend NOT Buying/Using FVP Brand Water Pump from RockAuto

[ZBrink]

This post is long over due and I will try and take photos to add at some point. Bottom line, the FVP water pump did not fit properly with the other OEM LT5 components.

At some point I purchased the water pump from RockAuto (FVP # 1307180) to replace my OEM pump which had its bearing going out. I think the FVP was the only available pump on the open market at the moment of purchase.

We installed the pump at Jim Voter's house. The pump itself installed fine and functions fine. But when we went to install the air horn, the alternator (which has a bracket that bolts to the water pump) was now seated too high preventing the air horn from being installed.

The best we can figure is the (3) holes on the FVP water pump (where the alternator bracket bolts to) are out of spec, raising the alternator bracket, which in turn raised the alternator, preventing the air horn from being re-installed. We were unable to make any adjustments to the other alternator brackets/bolts which would make an difference.

So, I recommend staying away from the FVP water pump.

[Young1]

Hmm. I have a GMB water pump on the shelf also purchased from RockAuto. Hmm I wonder if it will have the same issues. I was told that GMB stands for General Motors Brazil. 🇧🇷 Is that correct?

[ZBrink]

Hmm. I have a GMB water pump on the shelf also purchased from RockAuto. Hmm I wonder if it will have the same issues. I was told that GMB stands for General Motors Brazil. 🇧🇷 Is that correct?

GMB is GM Brazil. When we had our WAZOO holiday lunch back in December, we were discussing what happened with my install. Terry mentioned that there had been fitment issues with the GMB water pumps in the past but no one is known to have had installed one as of late to know if that had been worked out.

Please keep us updated if you install the GMB!

Phil is rebuilding my OEM one for me to keep on the shelf and Jerry sells the gasket.

[Matt Dawes]

Hmm. I have a GMB water pump on the shelf also purchased from RockAuto. Hmm I wonder if it will have the same issues. I was told that GMB stands for General Motors Brazil. 🇧🇷 Is that correct?

I also ordered a GMB from Rock Auto and have been in the process of changing it out, off and on for the last two weeks.

If you do not have a set of plenum gaskets on hand, get some.

Keep track of your screws! In the pump alone there are 16 screws - 4 different lengths and two head styles.

Even though the FSM does not mention removing the plenum, do it anyway! You will need to remove all three AC compressor screws and wedge it up a bit or you will NEVER get all 16 screws in the pump to line up and you will cross thread a couple. Clean your screw thread really well, it will help.

The pump to thermostat hose is a real challenge to get off, especially if the factory spring clamps are still in place. I went ahead and removed the alternator, the oil pressure sensor and oil cooler lines to make more space to work. I also loosened the clamp on the receiver/dryer so it can slide up and down. This is a good time to replace the hoses if you have any doubts at all about their integrity. I considered removing the oil filter adapter also to make even more space to work but figured that might be going a little too far.

And that is where I am...

My hoses came in yesterday. I will resume work when it warms up next week and will report back if I have any further issues.

[Dynomite]

The GMB and FVP water pumps look identical......
Keep us posted on any issues and thanks for the Water pump installation details👍👍

I know it is a tight fit for the Alternator, Air Horn and Water Pump as I have used several different 124 amp and 200 amp Alternators. I forget which Water Pumps I used but did install one Water Pump in which the impeller spun off the drive shaft inside the Water Pump (That was a bit difficult to diagnose) 😁

[A26B]

I also ordered a GMB from Rock Auto and have been in the process of changing it out, off and on for the last two weeks.

If you do not have a set of plenum gaskets on hand, get some.

Keep track of your screws! In the pump alone there are 16 screws - 4 different lengths and two head styles.

Even though the FSM does not mention removing the plenum, do it anyway! You will need to remove all three AC compressor screws and wedge it up a bit or you will NEVER get all 16 screws in the pump to line up and you will cross thread a couple. Clean your screw thread really well, it will help.

The pump to thermostat hose is a real challenge to get off, especially if the factory spring clamps are still in place. I went ahead and removed the alternator, the oil pressure sensor and oil cooler lines to make more space to work. I also loosened the clamp on the receiver/dryer so it can slide up and down. This is a good time to replace the hoses if you have any doubts at all about their integrity. I considered removing the oil filter adapter also to make even more space to work but figured that might be going a little too far.

And that is where I am...

My hoses came in yesterday. I will resume work when it warms up next week and will report back if I have any further issues.

Here is the Water Pump Bolt Placement Guide. It is available for free download on Jerrys Gaskets, along with quite a few other references.

https://www.jerrysgaskets.com/coolant-pump-bolt-placement-guide/

https://cdn10.bigcommerce.com/s-nkg90o/product_images/uploaded_images/lt5-wp-bolt-placement.jpg

[Matt Dawes]

I also ordered a GMB from Rock Auto and have been in the process of changing it out, off and on for the last two weeks.

If you do not have a set of plenum gaskets on hand, get some.

Keep track of your screws! In the pump alone there are 16 screws - 4 different lengths and two head styles.

Even though the FSM does not mention removing the plenum, do it anyway! You will need to remove all three AC compressor screws and wedge it up a bit or you will NEVER get all 16 screws in the pump to line up and you will cross thread a couple. Clean your screw thread really well, it will help.

The pump to thermostat hose is a real challenge to get off, especially if the factory spring clamps are still in place. I went ahead and removed the alternator, the oil pressure sensor and oil cooler lines to make more space to work. I also loosened the clamp on the receiver/dryer so it can slide up and down. This is a good time to replace the hoses if you have any doubts at all about their integrity. I considered removing the oil filter adapter also to make even more space to work but figured that might be going a little too far.

And that is where I am...

My hoses came in yesterday. I will resume work when it warms up next week and will report back if I have any further issues.

I finally finished up the water pump job along with new silicon hoses. I cleaned up a few things under and around the plenum before bolting it back down. The air horn cleared the alternator and went back on fine, so I guess I got lucky on that one.

The hold down clips for the IAC and IAT broke, I need to scrounge some of those up.

Over the course of the next two days I pushed 3 gallons of 50/50 classic green into the system. No leaks!

I'm on the road again, now for a good wash.