Can the timing chain be replaced without removing the head. I do not believe that the pistons hit the valves. The crank still turns with out hitting anything.

 

yes. you just need to take the valve cover, the crank balancer pulley and the timing case cover off. you should do a compression leak test to find out if your valves are okay

 

+1, you do not have to pull the head, you do however have to pull the cam gear, so don't forget to line up everything as best you can & mark things also (why not).

You can remove & re-torque thr cam gear bolt by putting the car in gear & have someone "stand" on the brake pedal....but, it is far safer to buy or rent the cam gear holding tool, then there's no chance of accidently slipping a tooth during re-assembly.

 

Thanks for the replies! I don't know if I am going to fix it yet or sell the car as is. Can anyone confirm that this engine is a non interference engine by chance? Thanks!

 

It's not an interference motor. Where are you located?

 

umm the r53 w11 definitely IS an interference engine. but dont just go selling the car so quick at least try to find out what exactly is wrong. its really not a difficult job to do if you have experience and it could be something small. check the tensioner and reset the timing and do a compression test and see what happens. besides bent valves aren't that expensive to replace, any machine shop can reseat some new valves for you

 

Thanks for the replies. A few dealers are telling me it is a non interference engine. My father, who use to be a mb tech did a leak down test and determined 90% sure that there has been no interference with the valves. It also cranks freely. The chain is completely gone and is probably inside the engine. What concerns me is why did it break in the first place? He simply does not have the room or time to do any service on it. I think I am just going to list it on eBay. The car has EVERY option, which makes it harder to see it go!

 

It is a interference motor, I have seen bent valves before.
its possible your valves are already bent hence the lack of resistance.
Pull the valve cover pull the rockers
use a straight edge to see if any of them are low indicating a bent valve.

 

If the valves are good and there's no damage to the head, why not replace the timing chain? Do you have experience working on a car? The entire job shouldn't take more than a few hours.

Pull the valve cover, remove the belt and belt tensioner, then the crank pulley. Also remove the camshaft sprocket. Then just put the new chain on, line it up correctly, and go. I'd replace the guides as well depending on the mileage on the motor. Just easy maintenance so you don't have to go back in later. It really is a simple job. Might need two sets of hands, but that's about as extensive as it gets.

 

That's the basic idea, but there's a little more to it than that. The job is better done with some special tools and a well equipped garage. There are other jobs I would recommend before this one for the home mechanic.

 

I had no issues doing it this way. Used a puller for the crankshaft pulley. Did not use the camshaft sprocket tool, but instead the heavy foot on the brake technique.

What would you recommend that I left out? Not a smart answer at all, but actually curious.

 

Based upon your previous posts, you have a father that's a professional technician, meaning that you probably grew up with grease under your nails. With that background, a garage full of proper tools, and the backup of a professional mechanic, this job would seem easy. That's probably not the case for the weekend warrior. It's not the best idea to encourage novice enthusiasts to start taking apart their motors.

 

You've got the wrong guy here. No mechanics in my family, and actually no one with interest in cars except me. Learned everything myself. Did the job of timing the car with a Craftsman tool set that you could buy at Sears, a puller for the crankshaft pulley, and some common sense.

If the OP is not comfortable with doing the work than so be it. All I did was post to let them know that its not a very difficult job if you know how to turn a wrench. I respect your opinion as a professional in the business, but this isn't the first time I've gotten this type of reaction from you guys.

If you're not comfortable with doing the work, I would not try to tackle the task. If you think you can handle it, its really not that daunting. If you'd like to pm me, go right ahead. I'll offer all the guidance I can. If you're going to start doing your own work, I'd suggest picking up a Bentley Manual guidance. That's what has helped me through different projects.

 

Oops. Sorry for confusing you with somebody else. No offense intended, just a realistic warning for folks so that they don't get the wrong impression from the internet about the ease of a job. I heartily encourage folks to tackle jobs like intakes, intercoolers, catch cans: basically anything that's not steering, brakes, or will be really expensive to fix if it goes wrong.

 

i agree it really is a fairly simple job and i had very little experience the first time i did it. and you really don't need any special tools other then the crank balancer removal tool which you can rent for free from auto zone. for tightening the cam sprocket you can just hold the crank shaft still with a big wrench and use the timing chain to keep the cam gear from spinning

 

What did you end up deciding to do?