Should I have the timing chain done while head is off?

[rph74]

My 95 318ic is at the shop getting the head gasket replaced. The tech advised that now is a great time to get all the coolant/heater hoses replaced which are normally difficult to get to. I will get that done for sure, but he also advised that I get the timing chain, tensioner and guides done while I'm at it too. He said to do the tensioner at the very least.

Now this shop WILL allow me to order my own parts in, so I can get a decent price overall. With my parts and their labor the total will be right around $450 for the timing chain job. There is 141k on the motor. I'm already spending $2100 for head gasket/oil pan gasket/ coolant & heater hoses/ water pump replacement, and I'm leery of adding much more to that bill.

What are the chances of timing chain or guide failure, and how much would a timing chain job cost at a later date?

[Mary99]

Replacing tensioner is a good idea but that can be done by you on a later date with the right parts. Requires about 15 minutes to remove and replace in a DIY for the M42/M44. If the labour price is right, let them do it, if it is stupid...DIY.

Unless there was something terribly wrong with the timing chain, don't screw with it.

Firstly, timing chains are used instead of timing belts because they are suppose to outlast the engine and are never meant to be changed.

Secondly, if everything was tickity boo, don't let the mechanics touch the chain or the timing. As good and qualified as they are, factory set is the very best you can get, unless of course they have the BMW PC's and robots.

Thirdly, everything in the motor has worn and aged at the same rate. There's a certain amount of give and slack that sits in all the components creating harmony. Again, unless something is failing, disturbing things right now will only stress the worn parts. The stress of unforgiving new parts working together with fatigued older parts is not going to lead to good news in the near future.

Lastly, don't kid yourself...mechanics are a business. If the air in your tires costs money, the mechanics will find someway to convince you that the HVAC system will perform better with replacing all the air in your tires.