[Vwdiesel] changing the timing belt

[MLightner]

Message: 7 Date: Sun, 24 Dec 2006 15:48:53 -0500 (EST) From: Val 
Christian <val at mongobird.com> Subject: Re: [Vwdiesel] changing the 
timing belt To: vwdiesel at vwfans.com Message-ID: 
<200612242048.PAA13466 at swamps.roc.ny.us> Content-Type: text/plain; 
charset=us-ascii

>> procedure itself removes as much error as practically possible.  That's 
>> why you time the crank to the valves first, then the pump to the crank. 
>>   Doing it in that order removes any error accumulation.  There are no 
>> shortcuts that leave you with perfect results.
>  
>

>	James is correct with respect to priority of alignment,
>	but physically, the belt runs from the crank to the pump 
>	to the cam to the adjuster.  The precision is on the other
>	side of the crank from the adjuster.

>	If the crank to cam is off, you can damage your 
>	valves very quickly, once the parts start moving.  Even if
>	there is no interference when turning over the engine by hand,
>	there can be some interference as the engine dynamics of running
>	come into play.

>	Take the time to get the crank to cam perfect.  

>	Normally, if you have the crank to cam timing correct, the engine
>	will run, even if the pump is off a little bit.

>	Also, as you know, there is no key on the camshaft, and
>	it is a friction fit.  Torque the cam carefully.  To much, 
>	and you can break things, too little and the sprocket pulley
>	may slip.

>	I've already told the story, but I had a Rabbit, where the timing
>	was never changed, from the factory, and one day the cam
>	sprocket slipped.  It bent a few valves and dimpled a few
>	pistons, and forced me to do a top overhaul when I wasn't 
>	planning on it.  

>	Your mileage may vary, but I torque the cam sprocket to the
>	rated torque, and then impact it (usually a hammer tap on 
>	a box wrench), to get it a little snugger.I estimate that
>	I torque it to 85 instead of 65.  Cam material is brittle, so
>	you don't want to overdo.

	Val

How about using an (accurately adjustable) impact gun on the cambolt, or is that a no-no?

>	ps: If you're struggling on this over the holiday, email me, 
>	and I'll give you a phone number so you can call with questions.

Thanks, nice offer; it's kinda cold and rainy here for the next few days though, so the Jetta project has kinda gone to the back-burner for now.

Mike


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