Centrifugal.

The Renault had been making some unhappy noises from the engine bay recently, bad bearing kind of noises. I drove it to work and back and on the way home it decided to buck and jolt badly, feeling like a bearing jamming up (more on that later).

old pump

After having to purchase an 11mm wrench (not a real size, why it’s used is beyond me) I removed the water pump. Due to the design, it was impossible to remove by hand, as the bolts undo and the pump came off with a gentle tap, but the impeller got stuck in the aperture with the pulley wedged against the frame rail. A bit of wiggling and there was 1/8″ holding it back so a thump from the bottom of the mallet handle saw it liberated onto the floor.

coolant

I’m quite impressed by the coolant. It’s very clean, all things considered. This is a good thing.

water pump removed

Water pump aperture, including original gasket, which probably could have stayed, in hindsight. Note the really large space to work in (by general Renault standards, at least. I can get my hand in there and even see what I’m doing. Luxury).

gasket scraper

Spent an hour swearing at the old gasket, which was particularly awkward to remove.

no more gasket

Eventually it did come up clean. I’m just glad the block is cast iron because the angle I was forced to work at with the blade would have scratched and taken chunks out of any softer metal. Surprisingly also, the pump housing is remarkably rust free where the impeller spins, so I’m guessing this coolant does have some anti corrosion properties.

new pump

The new pump came with a new gasket (which didn’t fit very well, the holes didn’t line up properly) and has a different impeller design. Previous one was a pressed steel affair which was effective enough, had 4 vanes. This one is cast metal and has many more (and upon actually having run it now, pumps a much higher volume of coolant, particularly at idle).

sealant

Gave the gasket a coating of sealant and installed the bolts, which were held in place by the gasket (useful side effect of the holes not lining up well).

pump in place

There was a moderate period of jigsaw/Jenga type thought and experimentation that occurred before the pump went in. In the end, the bolts had to be in place, the pulley had to be on the shaft but not attached so the pulley could wobble about enough to allow access to put the pump in place. Thankfully there’s enough room to see one bolt past the frame rail and also space to stick a locking rod so the pulley bolts can be tightened.

alternator bracket

Then it was time to put things back on! Alternator and aircon compressor bracket assembly first.

alternator

Alternator with top adjustment bracket.

compressor

Finally, aircon compressor and belt, which took a while to remember which way round all the pulleys it goes.

battery

Finally, the battery tray and battery went back in. Filled up the coolant and let it burp as best it can with the engine off.

grubby

Been a while since I’ve had grubby hands, made a change from moving boxes and furniture.

running

Finally, all buttoned up, topped up and running. Aircon even works still, which is nice. There howling bearing noise is gone, but initially it was still bang thump, kangarooing and running intermittent badly on the test run. This was traced back to a rubber bungy that had split and fallen off one of the big spigots on the brake booster. Replaced that with a short length of pipe with a wire nut stuffed in the end because that shouldn’t split now. Normal, smooth running resumed. This fuel injection system really doesn’t do well with vacuum leaks at all.

It’s nice to have it back on the road, even if the front brakes are now sticking because they’ve not been used. Next job, that.

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