? Noise, Vulcan 3.0 L engine, diagnose please.

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7440257 or
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(In a 2001 Mercury Sable sedan) This Ford Vulcan V6 is a 3.0 L with a pushr od valvetrain arrangement. The common 6g alternator is in the center of mos t of the vid; however, the sound isn't clearly coming from there. The noise is loudest shortly after starting and then it subsides somewhat. It doesn' t subside much.

I initially suspected the alternator, but I removed serpentine belt and han d-turned the alternator to inspect it. It turned smoothly without noise. No ne of the other pulleys seemed to be have bearing trouble either (although I'm not clear how to test them exactly).

The recording is from a simple Samsung Galaxy Centura cellphone, so the aud io low quality, but it does reveal the noise in question. (I'll try to edit it to eliminate the video element to reduce size. I apologize for now for the raw form.) The car currently functions fine except for the noise, which is audible a l ittle to me while driving.

I'm guessing the valves are in trouble, but I'm not sure, and I'm not sure what exactly would be wrong with them. And it still could be the alternator . Maybe (although it seems to turn silently unattached) the tension of the belt on the bearing will cause it to misbehave. What's my next step in dia gnosing this problem?

Reply to
Nehmo
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From my knowlege of the vulcan in that application and the very poor sound recording I would say you have a bad belt tensioner or idler pulley. VERY common problem, easy to fix and not too terribly expensive. I've replaced the bearings themselves, but easier to just get the kit with the bearing pre-installed in new pulley

Reply to
clare

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you missed a step. Start the engine with belt removed. If the noise it totally gone, you'll know you are headed in the right direction.

GW

Reply to
Geoff Welsh

Cam position sensor is a common noise maker in a 3.0 Vulcan. That is if you have coil packs and not a distributor. Sensor takes place of distributor.

Reply to
repairman54

I was under time pressure when I had the belt off, and I wasn't thinking ri ght. I was thinking it was dangerous to start without the water pump turnin g. That's wrong, of course. For a short period of time, an engine, particul arly a cold one, can survive without coolant circulation. Anyway, upon another careful inspection of the sheaves (pulleys), I could s ee the end plate coming off the AC compressor. This turned out to be the so urce of the noise. Upon researching the problem, I learned other Vulcan 3L owners dealt with similar AC compressor problem by bypassing it with a shor ter belt, and that's what I did. I used a 82.5 inch 6 rib (825K6) replacement serpentine belt

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. It rubs a bit, but it's tolerable. I took some pics during the repair and later discovered Google Photos, *wit hout my intervention*, had composed a slide show story. Considering I contr ibuted no editing, it's a testament to the advance of Google's software. ht tps://plus.google.com/113157811476977440257/stories/2c87e141-7aa5-3b40-9a7e -01e0029e6b6014729d54aa1/1?authkey (I had trouble getting the old belt off; most of the pics show that.)

Reply to
Nehmo

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