Crankshaft pulley noise?

[Ron T.]

Its been a while since I've been on the forum, an odd engine noise brings me back. My gas 97 4.0L Discovery has developed a disturbing noise from the front of the engine that clears up as the engine warms up. We've been having a more typical winter this year and even with the block heater on I'd expect exterior parts of the engine to be in the -30's C in the morning. For the first couple of minutes after the engine is started there is a noise, sometimes like a loud metal on metal rattling noise coming from the front of the engine (at those temperatures even rubber sounds like metal on metal, especially the door seals when you close a door). I've checked out the fan clutch, water pump, alternator, A/C pump, and P/S pump, and they're not the source. That left me with the serpentine belt tensioner and the crankshaft pulley. I wouldn't have suspected the crankshaft pulley until I read an online post that said that there is rubber in the crankshaft pulley assembly and when it starts to fail it can make noise, including a rattling noise. Has anyone else had this problem, and if so, what was the solution?
Ron T (in Yellowknife, NT, Canada)

[singingcamel]

Pull the belt and spin all the pulleys. Also I would be thinking cats converters, they'll rattle and can sound like a front engine noise.
Make sure you grab the water pump by the pulley and yank up,down , just don't spin it . I've seen em spin without noise but by yanking on em will produce unwanted play..good luck and stay warm eh!

[Ron T.]

Thanks for the advice, but things have changed course over the last few weeks. Just after the new year I had a valve lifter give me some trouble. I took it to a local mechanic with a good reputation. It was over three weeks before he could take a look at it. In the meantime I was planning on doing a lot more work to the engine as five years ago the front engine cover gasket went and I drove it with all of the coolant mixed with the (synthetic) oil in the oil pan. Surprisingly it survived that, but two years ago I had the main bearings replaced. With over 290,000 KM on it, and given its history, I thought it was time to tear it down. But the mechanic found me another engine with only 140,000 KM on it. That should be installed this coming week, and while its in the garage I'll try to catch up on some other smaller maintenance items. BTW, this winter we had temperatures closer to typical, but only a couple of days with -40 or colder, and our coldest day was -43C. I heard recently that Land Rover opened a cold testing research facility in International Falls, MN, when they're serious about cold testing they can come up here, like Porsche does.

Pull the belt and spin all the pulleys. Also I would be thinking cats converters, they'll rattle and can sound like a front engine noise.
Make sure you grab the water pump by the pulley and yank up,down , just don't spin it . I've seen em spin without noise but by yanking on em will produce unwanted play..good luck and stay warm eh!