2004 R50 Justacooper 5 speed manual 171K miles. I'm a new owner. Bought it noisey

I have already installed a new timing chain tensioner (which helped with some of the top end noise (a sharp cracking which has now become intermittent instead of constant).

But it allows me to now also hearing a deeper noise. Perhaps it's the harmonic balancer and maybe the new tensioner just isn't enough to compensate for the 171K miles of wear on the chain?

The balancer rubber is pretty much kaput, by the looks of it while it is stationary.

video of noises


I'm thinking next step is replace the timing gears, chain, and the harmonic balancer? (I have a second but partially disassembled R50 motor I picked up for $100 that has a decent looking pulley on it).

Any thoughts on what's producing the noise? Any chance it is valve guides in the cyl head?

I have little info on the history of the car other than the PO claimed they were told it needs a new motor. I'm not convinced it does.

 

I would replace the timing guides as we see them make noise on higher mileage cars.
We have seen the R50 crank pulleys fail to, but not usually noisey.

 

Hey Way what do you charge for th timing guide service - 04 r50 base.

 

I practiced today on a partially disassembled craigslist motor I picked up a while back. I got the damper pulley off of it and the timing cover/oil pump plate.

Using the same 3-jaw puller, I tried to pull off the timing gear on the crankshaft and it wouldn't budge. Granted, I didn't put 10 tons (or should that be tonnes?) of force on it, but about as much as I felt comfortable putting on the gear and the puller.

I also noticed in the manual that the new gear is heated a few hundred degrees before it is slipped on.

So is there a known work-around instead of using the BMW special tool?

Also, do I really need to remove the AC (I think it's the AC pump) on the front of the motor to remove the timing cover while the engine is still installed, or is is do-able without disconnecting all of that stuff up front?

Thanks for any help.

 

Following up on this for anyone playing along at home.
I replaced the timing chain, the gears, the guides, the tensioner. While rotating the engine over by hand to ensure I put it back together correctly before I put the timing cover on I felt an easy spot while going over tdc. This is pretty normal for most 4 cylinder engines I've felt with a bit of miles on them, but the accompanying thunk that followed didn't make me feel so good.

The tighter chain and my familiarity with what it felt like to take up the clutch spring tension while rotating the engine allowed me to feel the thunk and repeat it at tdc and bdc at will.

So I pull out the spark plugs, get the engine between the point where it gets easy and the Thunk, and I push down on the #1 piston through the spark plug hole using a long 1/4" ratchet extension... THUNK! as it slip down a good bit.

Next step is to see if it' is the road bearing that is gone, or if it is the piston/wrist pin or something else in the little end that has let go.

If it were the rod bearing and crankshaft, I would think I would have had very little to no oil pressure when I pulled the valve cover off and ran it for a few seconds.

I'll chime in again once I determine what it actually is.

(anyone got any spare stock pistons sitting around that they don't want?)

 

...waiting for the next episode.

Motor on!

 

Guess you found the source of the noise

Can't you use the spare motor?

 

I don’t have this thud dull le de dunk de dunky dunky, but an update would be nice. It does seem like the bearing for the piston is shot to hell.

 

So how did you end up getting the timing sprocket off of the crankshaft? Did you have to heat it? What tool did you use? I'm doing my timing now and can't get it off with a 3 gear puller.

 

Hate it when we dont get to see the final result...

 

You really need something like this to pull the gear off the crank.


I read some people have used a dremel an a cutoff disk to split the gear an remove .

 

Ok, just picked this up. Closest thing I could find.

Thanks!!