Water Pump showing its age

[Garth]

I was working my way back home (Canada) from southern Texas last month and stopped for gas in Garden City, Kansas. It was there that I crawled under the engine to check on things that I noticed coolant coming out of the weeping hole of the water pump. Needless to say that the rest of the trip home was overshadowed by thoughts of being stranded on a lonely stretch of highway. Fortunately, the pump held together for another 1200 miles to our home. Now that I’m home and close to my tools, I’m looking at replacing the water pump. The motor home has a Ford E350 chasis and a 460 motor. The pump still leaks coolant from the weep hole but not enough to create a puddle on the ground. The heat from the motor seems to dry it off leaving a yellow crystal like residue behind. There is also coolant residue further back from the water pump on another seem which I’m guessing is the timing chain cover.

I haven’t had much experience with water pumps before, I’ve changed only one on a Dodge 250 Ram Van after it started making a racket and leaking coolant badly. It seemed to go quite suddenly, whereas the water pump on my motorhome held together for longer than I expected. I’m wondering if those who have had dealings with water pump issues could comment on their habits ie. do they tend to give you ample warning before they go completely or are they an unpredictable part. Also, could coolant be leaking from the timing chain cover as well??

I’m also hoping that there might be someone out there that has changed a water pump on a Ford 460 engine that could give me a heads up as to how difficult it might be and possible issues I might encounter. I watched Eric’s video on the Tahoe water pump that he changed and it looked straight forward. But I also came across a video on Youtube of a guy who was working on a large Chevy 460 something that had busted a few of the bolts while trying to take off the water pump. I’m wondering if the job I’m planning to tackle will have a few surprises like this.

Topic

[Nicholas Clark]

The 460 is stone age tech. If the weep hole is weeping, then yes, it’s time to change the old water pump. Just look up a video on changing a pump on a ford 460, and you should be fine. They haven’t changed much in all those years. Edit: If you are worried about breaking bolts, shoot them with PB Blaster a few hours ahead of time.

[Mike]

[quote=”Gearwrench” post=175496]I haven’t had much experience with water pumps before, I’ve changed only one on a Dodge 250 Ram Van after it started making a racket and leaking coolant badly. It seemed to go quite suddenly, whereas the water pump on my motorhome held together for longer than I expected. I’m wondering if those who have had dealings with water pump issues could comment on their habits ie. do they tend to give you ample warning before they go completely or are they an unpredictable part. Also, could coolant be leaking from the timing chain cover as well??

I’m also hoping that there might be someone out there that has changed a water pump on a Ford 460 engine that could give me a heads up as to how difficult it might be and possible issues I might encounter. I watched Eric’s video on the Tahoe water pump that he changed and it looked straight forward. But I also came across a video on Youtube of a guy who was working on a large Chevy 460 something that had busted a few of the bolts while trying to take off the water pump. I’m wondering if the job I’m planning to tackle will have a few surprises like this.[/quote]

When it comes to pump failure, it’s a case-by-case thing, depending on the nature of the failure. If you’re thinking about nursing a few more miles out of your weeping pump, I’d recommend against it. Coolant leaking from the weep hole tells you that your impeller shaft bearing seals are shot, and the bearings are now being lubricated with coolant. The bearings could fail at any time, especially after all those highway miles. As for the timing cover, that’s probably a sign of the pump leak, but it’s hard to be definitive long distance. Your timing cover has coolant passage “ears” that mate to the cylinder heads, so it’s possible there might be a leak at the rear face of the timing cover too. A good photo of the condition might help.

When buying the new pump, make sure you specify the vehicle type and year. It’s possible that the water pump on a haul beast like a motorhome might be a higher capacity unit than one from a Lincoln Town Car.

I’m going from ancient foggy memory here, but I think your new pump will come with two gaskets. One is for the mating surface between the rear pump plate and the timing cover, and the other gasket goes between the pump casting and rear pump plate. Clean all 4 mating surfaces well and use a gasket sealant.

I also seem to remember that your timing cover is aluminum, so you might have to deal with galvanic corrosion on the steel pump bolts. Apply a good penetrating oil and let it sit at least overnight. When you’re ready to undo the bolts, a quick first tug in the “tighten” direction often helps to release the corrosion bond. Wire brush the bolt threads once you’ve got the bolts out, and using a thread chaser in the bolt holes will help too.

It would be a good idea to replace any hoses that attach to the pump, as well as their clamps. Might as well change the pump belt too.

[Garth]

Thanks, Evil-i and Hockeyclark, for the advice. If I can manage a decent photo of the leaking area, I’ll post it to see what you think. Thanks again.

[Garth]

Used your suggestion to first tighten the bolt a bit before turning it off. Great technique! All the bolts came off nicely. Question about cleaning the thread holes with a thread chaser. I have a tap and die set and have used my taps in the past to clean out thread holes, but now that you mentioned a thread chaser, I’m thinking that maybe using a tap isn’t the smartest thing. I spent some time hunting the internet for an appropriate “thread chaser” tool that you mentioned in your last post but found non that meant for thread holes. Some of my bolts are 4 inches long, so I would need a long enough thread chaser to clean the threads in these deep holes. I did come across an article on the internet that explained how to make a home made thread chaser from a similar bolt that fit the thread hole. This seems like the best bet for me, but I was just wondering what you use for “thread chasers”, whether it is a commercial kit or something you’ve made yourself??

P.S. I decided to leave the timing cover alone as there was no coolant in my oil pan. The timing cover job just looked like too much work for the little amount of wetness coming from its seem.

[Author]

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