Time to fess up! Ford Racing waterpump failure probably my fault...

[CJ Steak]

Hey everyone, I posted this up on MGE, but since it was probably my fault the water pump failed, I felt it was only fair to post my findings here as well.




"I got the new pump in the mail yesterday (thanks Summit!), and the first thing I did was touch up the welds with my welder. I assure you that plate isn't coming off anytime soon.

I just took it for a test drive and the car definitely runs cooler than it ever has.

But.

I was adjusting the timing, and mixture screws on the carb, which involved a quick rev here and there. I noticed that at not much over idle, the bottom hose collapses completely.

That would leave me to believe that while driving the water pump was cavitating with nothing in it, then when I dropped down to an idle, it got a big rush of coolant. As we all know big rushes of uncompressable liquid into mechanical parts is never really good.

I think that's what caused the plate to snap off.

Needless to say, after all this time thinking about the most technical aspects of the conversion, I failed to put my brain back into simple mode... like checking to make sure the lower radiator hose had a spring in it.

I guess my lower radiator hose (have no idea what it's actually for) is actually an upper radiator hose for a different car.

Lesson learned!

I'm a fool."  

-Chris

[kstevusa]

Wow Chris, glad you found the problem.  sometimes we all have a failure to relate to what is happening.  I have had some "Ah Ha" moments also.

[MGB-FV8]

Chris, most of the time when you buy a bottom radiator hose it doesn't come with the spring anyway.  If someone doesn't know to transfer the spring, or, forgets to re-install it then a problem will arise somewhere down the road.  I've seen people chasing overheating problems not realizing that the bottom hose collapsed under high RPM; especially, when looking more than normal at idle.  This is why I always rev-up the engine hard a couple of times to see if the bottom hose collapses.

Many people have also installed reverse rotation impeller water pump on older engines without realizing that a serpentine belt system rotates the water pump the opposite of the early v-belt type; it causes some people to never figure out why their engine overheats.

As Kelly mentioned, don't feel bad as I too had my own brain cramps; that's how we've learned how to trouble-shoot the humble way.  Thirty five years later, I still hear my friends humorously remind me how I once installed a thermostat backward...........(in a Ford Capri, easy to do)

[CJ Steak]

Haha... thanks for the kind words guys.

Needless to say, I WILL be revving/checking all lower radiator hoses from here on out.

This is actually a really good lesson, because it can avoid a ton of issues.

On to the next lesson learned now...  

[DiDueColpi]

Hey Chris,
If no one made any mistakes how would we ever learn?
I am pretty certain that I personally know everything that won't work, generally through the immense power of ignorance and pride.
Your lower rad hose shouldn't really need any support. Be it a spring or a sleeve or Viagra etc.
The cooling system, working correctly should be under 13 to 18 or more psi.
That means that a 2" hose will have approx. 56 lbs.of pressure trying to keep it inflated.
The water pump isn't capable of that kind of suction so possibly you have a rad cap issue.
If you think of the system as a whole, the pump puts out as much as it draws in.
Which in a closed system means there is no chance of a vacuum to suck the hose flat.
The only other possibility would be an air pocket in the cooling system that would allow the water to displace enough to collapse the hose.
What I'm getting at is that the flattened hose is a symptom of another issue and not the cause of your problem.
Hope that helps
Cheers
Fred