Ford CMax 1.8 petrol - Disconnecting the alternator

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Sun 12 Sep 2010 13:15
Ford CMax 1.8 petrol - Disconnecting the alternator - Chris M

I'm getting a whining noise when the engine is first starting in the morning which disappears a soon as the engine has warmed up a little. Sounds like the water pump bearing, but the noise is coming from more in the direction of the air con pump. Switching the air con on and off doesn't make any difference though.

I have checked the water pump in situ and there is a very tiny amount of play in the bearing, but otherwise it feels smooth. I'm wondering about slipping the belt off that runs the water pump and alternator and starting the engine. This should rule them in or out as a possible cause.

Question is, will disconnecting the belt make the engine light come on and will I then need to visit Ford to get it reset? The CMax is canbus and for all I know it may not even start with the alternator not working?

Edited by Chris M on 12/09/2010 at 13:16

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Sun 12 Sep 2010 17:02
Ford CMax 1.8 petrol - Disconnecting the alternator - freman

It could be the belt slipping over the alternator pulley.

I had this occur on my 1600 Escort particularly during cold snaps. I would think that the design of these engines are pretty much alike & the drive belt is only tangential to the pulley i.e it does not wrap round it.

It is caused by the extra load on the alternator trying to recharge the battery after the cold start.

I would say live with it to see what develops

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Mon 13 Sep 2010 06:11
Ford CMax 1.8 petrol - Disconnecting the alternator - Chris M

Thanks freman. I think it unlikely that it's the belt slipping as that would be more of a squeal. Also, it's a multi V belt which is less likely to slip and secondly, the belt runs round a spring loaded tensioner pulley.

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Mon 13 Sep 2010 18:22
Ford CMax 1.8 petrol - Disconnecting the alternator - freman

This is the set up as my Escort. After the initial tension has been set by the spring-loaded pulley the mounting bracket is then locked by a set screw so the tension on the belt does not change to allow for stretching.

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Mon 13 Sep 2010 18:42
Ford CMax 1.8 petrol - Disconnecting the alternator - bathtub tom

You could try dribbling a little bit of water on the belt as it's running and see if the noise stops.

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