jenessa

This a tech question.. My serp belt is too loose all symptoms point to altinator failure..
The lights on the dash, batteries dead. When I tug on the belt its loose,
So Iv replaced the belt tentioner, what a headach , the problems still there.
What can I do to tighten the serp belt? the altinator is out of the question
what else is there to adjust please I understand what ever you can explain, thanks.
jenessa LS400

hlovepenn

You didn't say which year LS400 you have, but you might check the fan bearing--if it has gone out, the belt will be very loose. Also, the serp belt might be mis-installed. Check the belt schematic on the inside of your hood. If you need to, since the water pump drives off of the timing belt, you can charge the battery, take the serp belt out and then you can drive to your nearest Lexus mechanic without the cost of a tow. The steering will be a bit stiff, but you will be able to make it if you take it nice and slow. The alternator is not hard to pull if you have a ramp to get access to the bottom of the engine. Pull the bottom wind shield and remove some of the bolts holding the lines which may be in the way and then remove a bolt and screw from the alternator, unsnap the connectors and it is out! If it is bad, you can get rebuilt ones on the internet for about $160 plus shipping or have it rebuilt at a local alternator shop for about the same price. In fact they will probably charge $60 or so to remove and reinstall it. Good luck!