need help......CAS= no crank

[keg9]

Hello to all,

I am new to the community. I just picked up the car that I have always wanted. A 300zx. Now its not the exact one that I wanted but ill get it there It has good bones. My issue is that it has 150k miles on it and the first ting that I did was the 120k timing service cause i didnt know if it had been done. Before I did the job the car ran but would die out due to a bad alternator. It also ran sluggish and I thought that could have had something to do with that system or the timing system. So i did the timing job( I did remove the CAS and spin the engine with CAS off) and spun the crank 720 degrees THEN put everything back together. when I went to start the car it did a small like half revolution (like a dull crank) and it slowed down then stopped and would not crank. Sounds like the starter is being stopped. I thought the starter was bad so I pulled it had it tested and solenoid was bad so i got another starter. and the same issue occurred. I then thought that I slipped a tooth and went back down to redo the tension and reset the timing belt. after all things were put back together it has the same issue, it will not crank if the CAS is hooked up. If I unhook the CAS the engine will crank fine and I hear nothing coming in contact in the engine. Has anybody had this issue before. I have reset the timing and tensioner 3 times already ( I can do the timing job really quick now lol) My buddy up the street said to check the compression and make sure that each cylinder is getting its full range, he also said to check the starter voltage with and without the CAS hooked up to see if the CAS is grounding out the starting process. If you have any other ideas I can check please let me know.

[itsa300zx]

That is very bizarre, CAS should not bind up an engine.
Can you rotate the engine by hand/wrench via the crank pulley with the cas installed?
This will at least eliminate a mechanical interference issue if it rotates "freely".

[keg9]

Yes, before I put the timing covers on, I spin the crank. on the third time I even put the water pump tubing back on and cranked it without the timing covers just to make sure the timing wasn't slipping. It definitely sounds like something is stopping the starter from spinning or engaging.