I wouldn't trust them that long... They are plastic (20 or so year old plastic @ that now) that has been heat cycled a multitude of times. I like to see the lower rails done around 300K.

You'll be pulling the front cover...which can, by some account, be done with the heads on but I'd recommend doing so while the heads are off for machining etc..

Also a great time to replace the water pump and the timing gears which are Sure to be worn @ 350K.

Jonathan

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Jonathan Hodgman
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