Hello Everyone...I think this may be my first post?!
I have an R53 I bougth with 78,000 miles 4 years ago. I am now at 155,000 miles and just finally took a deep breath to change the timing chain and guides.

Long story short, when I opened up everything the cam arrow mark was no where near the chain link mark. While the crank arrows were a couple teeth off from chain marks.

My questions are
1. How was my car running without timing issues prior if the marks are no where near what they are supposed to be? At least from everything I have read here the arrows and marks need to be matching.

2. Is it really just a matter of matching these marks?


Thanks in advance!

 

As the chain has more links then there are teeth on the cam sprocket, it is not possible for the marks on the chain to line up with the mark on the cam sprocket all the time. If I remember correctly it took eight revolutions of the cam sprocket on a V-6 I was working on until the marks lined up again.

 

Yeah, that's what I was thinking as well. Rotate the crank over until they line up. Taking the spark plugs out makes it much easier.

 

I nominate you for NAM's first ever science award.

 

Would that be the Brass Hammer Award or the coveted Automatic Beeeeday Award?

 

Thanks guys I rotated the crank until marks finally matched! All "in time"

 

I have just finished my first head gasket replacement on my Mini (always have your head checked by a machine shop.) Anyways, if you use the tool to hold the cam gear still while you loosen the cam bolt all you need to do is mark the gear and the chain with a dab of paint. If you don't move the crankshaft while disassembled, then all you do is reinstall the chain and check to make sure your marks line up. Seems scary at first, but it worked great for me.

 

Paint or white out works great.

 

Round two on this didn't work out for me. Started the engine after installing refurbished head and something is wrong. Maybe timing off a tooth? It runs, but spits and sputters. Definitely couldn't drive it. Gonna look into it tonight any ideas?

 

You did back off the lifter bolts when you moved the cam to match the crank?

 

Yes, I loosened all the rocker shaft bolts for both intake and exhaust to be able to turn the cam. After getting the cam,lined up and chain on, then tightened the bolts all down to spec. I followed ModMini's YouTube video for that part.

 

Hmmmm, the upper cam sensor working?

Any codes?

 

Doing a double check I found that I had forgot to plug in the throttle body. She runs now! Amazing what a difference that made. However, my root cause for investigating the head/ gasket is still there. Upon warming up it starts to run rough and then gets worse. Stumbles during acceleration and take off. Then completely drop cylinder three. I pulled the plug wire off and it didn't change the roughness at all. It did spark all the way out if the tube, so spark seems good. Maybe not good enough? How do you test that?

 

Fixed! My stumble into a missfire turned out to be a combination coil, plugs, and wires. Replacing each part made it a little better. She runs smooth now and it's been a few hundred miles, so it's Fixed!