No Start after timing belt

[E30andy]

Hey Guys!

Need some help.....my new to me 88 325ix coupe wont start after timing belt/spark plug/spark plug wire/distributor/and rotor change.

It started and ran prior but I have only owned for a week so not sure how well it ran.

I havent dived back into it yet other than to check that the plug wires were all routed correctly (they were), and the CPS was plugged into the correct plug (it was), but

I have been doing some googling and came across this thread....Look at post #34:

https://www.bimmerforums.com/forum/s...t-change/page2

Is it possible to mount this part incorrectly (#7 below from realoem)? I did the cam seals and didnt pay any mind to how things went back together.

https://www.realoem.com/bmw/enUS/sho...diagId=11_4365

I'm pretty sure the cam/crank timing is all good but I will recheck that when I start pulling things apart again. I have a running 89ix parts car so I can swap parts which should be a big help.

Thanks!

[tomstin]

I think you're going to have to pull things apart again to verify everything. And its always difficult to check your own work as you tend to assume. Remove the spark plugs and turn the motor over several times by hand, using a socket, on the crank pulley. Verify AGAIN the timing marks line up and there are no "hard spots" (valve hitting piston). Make sure the mount for the rotor is slotted correctly. My guess is you've missed something along the way.

[E30andy]

Thanks for the response! Is valves hitting pistons something I would feel or hear as I rotate the motor by hand? Thats my biggest concern but figured its something you would notice as you rotate the motor to confirm the timing marks are aligned.

[roguetoaster]

Valve to piston contact is felt when rotating by hand and heard when running the engine or using the starter. You don't want to hear it.

Not sure if you did it, but after every timing adjustment or belt change you should slowly rotate the engine by hand to feel for any contact, and then verify timing agreement before complete reassembly.

[E30andy]

Thanks roguetoaster! I did rotate by hand to double check the timing marks and didnt feel anything like I would imagine valves hitting pistons would feel like. Also, cranking the engine to try to start it after I had put everything back together did not reveal any unusual noises, just no-start.

[roguetoaster]

To elaborate on what tomstin wrote, also verify spark, as I'd bet that you simply don't have any if the engine isn't even making a hint of combustion noise.

[E30andy]

It did try to start just didnt "catch".....

[roguetoaster]

It did try to start just didnt "catch".....

No after the fact sort of combustion noise, or really violent ignition?

[E30andy]

No after the fact sort of combustion noise, or really violent ignition?

No nothing like that. I tore it all back down to the timing belt. Took off the rotor and the "rotor mount" which is what I believe is the culprit. I now see that the "rotor mount" is keyed (very subtly!). I'm a little stunned that that is not mentioned in any TB write-ups that include changing the cam seals (the only reason you would remove this part during a TB change). I gotta believe I remounted the rotor incorrectly being unaware of the fact it can only go on correctly one way.

I also decided to change the CPS while I am in there as it looks old and brittle and has some wires showing down by the sensor. Waiting for that part and then will button it all back up and keep my fingers crossed!!

[E30andy]

Started right up today after reassembly making sure the rotor was placed properly and using a new CPS!
Thanks Guys!!