Any idea where I can get those pulley bolts?

Ok found them at JLR in Annapolis, MD. Damned expensive!

 

Used grade 8 replacements after matching the threads, on mine.

Just make sure they are not too long, or they will hit the pump.

Cost less than a dollar for four, with washers.

 

So took out the water pump and split it into the two halves.

Only two bolts hold these halves together when not installed on car. The bolts that hold the pump onto the engine also help clamp the two halves together.

All these bolts do not touch the their respective holes in the front half of the pump. There is a small clearance. The bolts that screw into the engine block do not touch either the front half or the back half.

They screw into the back half of the pump and are entirely responsible for keeping the two halves aligned with each other correctly. No alignment notches

These two halves only have to be out of alignment a very small fraction of an inch, imperceptible to my eye.

If out of alignment then the impeller will scrape the housing in the back half making quite a noise.

In the pic of the back half if you look carefully you can see scrapes just above the lower lip where the impeller came in contact.

When rotating the assembled unit by hand there is no scraping it only happens under the load of the belt in tension.

So my theory is that if the bolts that hold the pump on the engine are not tight enough the prolonged tension of the belt may be enough to pull the halves out of alignment enough to cause the scraping.

The pump will still function but the noise is too much.

Now I am going to be paranoid about getting the correct torque settings when I install the new pump!

 

My water pump is taking the scenic route!!!!! It was promised by the 7th of this month.

• Nov 4, 2018
• 08:00am PST

• In transit
• SUMMERFIELD, TX 79085

• Nov 3, 2018
• 20:54pm PDT

• In transit
• GANADO, AZ 86505

• Nov 3, 2018
• 08:46am PDT

• In transit
• NEEDLES, CA 92363

• Nov 2, 2018
• 20:45pm PDT

• In transit
• LOS ANGELES, CA 90023

• Nov 2, 2018
• 03:31am PDT

• Departed FedEx location
• FEDEX SMARTPOST LOS ANGELES, CA 90022

• Nov 1, 2018
• 18:41pm PDT

• Arrived at FedEx location
• FEDEX SMARTPOST LOS ANGELES, CA 90022

• Nov 1, 2018
• 17:05pm PDT

• Picked up
• ARCADIA, CA 91006

• Nov 1, 2018
• 15:55pm PDT

• Tracking number provided

 

The Delco brand is a single piece unit, unlike the two piece, stock pump, on mine was. (What a cluster fudge of a design, fire that engineer, or give him a mop, & toilet brush.)

Better design, fewer leaks, as well as alignment issues.

What a cluster fudge

 

The supplier I ordered yet another 2 piece pump from also sells the Delco single piece design you mentioned.

I am trying to get them to agree to a swap. I did not realize there was a single piece design.

 

So ordered the solid one piece Delco water pump from PartsGeek a few days ago and they just cancelled the order with no explanation.

Ordered it from an AC Delco supplier just now.

 

Hope you have the same luck with yours, as i have had with mine.

Simplicity is the key to good design; On my first shop teachers desk, 57 years ago, & have never forgot it. Made a serious impact on my life!!!

 

Delco

Delco next to failed pump
So received my Delco water pump just now and noticed it has a rubber ring gasket that the two piece unit did not have.

Also the pump to engine block gasket is far sturdier than the one I had on from the previous water pump.

 

Looks like the ones i ordered, that so far works great.

Serious gasket included, not cheap paper.

 

Sounds good!

 

I used AC Delco in my 2000 S Type. It was also one piece and never had an issue after install. For my 04 XJR I installed Jaguar OEM unit. So far so good...

 

I hope I can say the same in at least 10k miles which for me will be several years.

My original, which I think was the original OEM pump, lasted 100k miles plus and it had the plastic impeller. Nothing wrong with it I just thought to replace it along with the thermostat while I was in there doing other work which was actually new coolant pipes etc for the extra SC radiator.

Everything is back together except for new antifreeze and finding a dropped socket.

 

I notice in the thread about the 5.0 liter water pump that at least one person shows a 2 piece water pump in a pic.

I looked at that thread because of my 2013 5.0 liter Range Rover Sport which had its water pump replaced by a dealer around 30k miles.

 

Just to chime in late on this thread, if I recall correctly, the ACDelco water pump has a metal impeller. If I understand the literature correctly, the reason the OE impeller is plastic is to eliminate the effects of electrolysis and cavitation erosion that metal impellers are susceptible to when operating in OAT coolant. Probably not an issue in the near term, but in the long term it could be (think of eroded metal particles circulating through your cooling system).

I've installed several of the Airtex OE-style water pumps on X100s, X200s, X308s, X350s and a Range Rover, and have never had a problem. But I did once accidentally remove the screws that hold the two halves together on a car whose valley hose failed after I had already installed the new water pump, so I realized the torque of those two screws is critical to having a pump that doesn't leak. And now, thanks to John, we also know that the alignment of the two halves is critical. Thanks John!

Cheers,

Don