Hi all,
I found a leak from the water pump this weekend :( It seemed to be coming from the bearings so I took the pulley off and found there was lots of play and water leaked as I wiggled it.
I spotted it before the water level dropped too low so I thought I'd got away without doing any damage but when I took the water pump off it looks like the play in the impeller was enough to cause it to rub up against the engine housing a bit:
(http://s23.postimg.org/3vqsdkeqf/IMG_20140907_200407.jpg) (http://postimg.org/image/3vqsdkeqf/)
and similar on the pump body itself (behind the impeller):
(http://s18.postimg.org/67543rw9x/IMG_20140907_200420.jpg) (http://postimg.org/image/67543rw9x/)
Although curiously there doesn't appear to be any damage to the impeller (the rust in the photo looks quite old and untouched)
I had planned on rebuilding the water pump (it's on a classic so replacing the whole pump is expensive), there's a kit including bearings/ shaft, seal and impeller but now that I've found the scoring I wonder how sucessful a rebuild will be...
I'm also wondering if I need to worry about the bits of metal now floating round the engine somewhere?
Any advice would be appreciated, this is my first time with a water pump so any general tips would also be welcome.
I had the same problem, but with no leak. My pump is driven by the cam belt, so real damage could have occurred if the belt went really slack due to the bearing wear.
I also had tiny bits of metal in the coolant when I removed the pump where the impeller had rubbed against the pump body. I flushed the system best I could and renewed the coolant so I'm guessing that has done the trick. As far as lasting damage I cant see any big issues, the particles were so small so I cant see any blockage problems or the like.
I'm not an engineer, so I could be wrong but I have not had any cooling issues since changing the pump and coolant.
I would just renew the pump complete, flush the system out and run it with clean water for a short test period. If no problems, drain and refill with the correct coolant.
I used to replace the internals on Lotus twincam pumps as they were expensive and the parts were the same as the 105e anglia which were cheap. Had to be careful as they could leak if you were unlucky.
It's driven off the fan belt so hopefully no cam issues...
This is a lotus 907 so quite similar to the twincams, hence my thoughts of replacing the innerds. Maybe I should just stump out for the complete pump and just count myself lucky it didn't do more damage :o
Thanks for the advice, very much appreciated
Like the guys have said, replace the pump, flush through with clean water for a test, then drain, check and refill with coolant mix. i would be surprised if there is any major damage through small particles of metal in the water system as most water ways are quite large.
Just try and get it as clean as possible, and make sure you give the radiator a good back flush as that is the most likely area if any to get a blockage.
HTH ;)
Like Benchmark I used to do Loti in the day.
I did identify what parts they used in the pump but have forgotten in the years since.
If I remember correctly even then I could only get pumps with plastic impellers so had to refit the old cast iron one - and often these were worn on the face abbutting the sealing gland.
The T/C pump was installed in the front cover and fitted all engines. It had an extra seal/teflon faced washer that enabled the old impeller to be reused. It was practical to recondition the front covers for stock.
There were so many variants of the 907 and every one I did was different to make sure you get the right one!
Dave