What does a bad circulation pump sound like?

[nigel]

One of my engines has started making a horrible sort-of-crunching / grinding noise that -seems- to be coming from near the water circulation pump. Its not a very regular frequency or in synch with engine revs but does increase in speed as you rev up. I can't think of a better way to describe this but the nearest noise I can think of that it sounds like is an old steam train engine.

There is also the odd clack noise now and again which may or may not be related.. Possibly this is just the exhaust flappers getting old. Or maybe something loose flapping around elsewhere.

For those of you that have changed circulation pumps - what was the symptom that made you change it? Any other ideas anyone?

Many thanks in advance,


Nigel.

 

[Dave S]

I had to have the circulation pump replaced on my 5.0 in my 240SD. It was making an intermittent squeeking and squeeling noise and it was replaced under warranty.

If you have a mechanics stethoscope, sometimes that is the easiest way to identify the source of your noise, If you don't own one, then I recommend buying one. I have used mine many times and find it very helpfull. They are inexpensive and a good addition to your toolbox.

Another way to identify the source of the noise is to remove the drive belt and spin every component by hand to see if it is noisy or if the bearings are not smooth.

Dave

 

[flarepoman]

stethoscope will do it, I keep mine on the boat!! Found a bad water pump on the engine one time.

 

[2000SEARAY280SS]

Another way to identify the source of the noise is to remove the drive belt and spin every component by hand to see if it is noisy or if the bearings are not smooth.

Dave

++1

if it is the circulation pump the pulley will be very lose the bearings often wear out on these units.

 

[nigel]

Thanks for your help...

I took a closer look today and could feel some play in the pump pully even whilst the belt was still on.. So removed the belt and spun the pump - which sounded horrible - grinding type of noise even when spinning by hand. I took the belt off my other engine to compare - and the pump on that one is silent.

So.. new pump ordered! Hopefully I'll be back up-and-running by the middle of the week...

 

[nigel]

Fixed!

Was indeed the circulation pump.

New pump has a reasonable but smooth resitance when you turn it - so I suspect my other pump is on its way out too.. Both old pumps span easily - although one was quiet.

Anyway - In the mean time I'm back running again.

Thanks for your help,


Nigel.

 

[2000SEARAY280SS]

Make sure you use RTV water sealer on the bolts that go through the water jacket. I do not recall which ones they are so I use some on all of them.

They will be the ones with corrosion on them.