My lady is a 1980 280zx auto that I probily should'nt have bought but I could'nt help myself. She did'nt run when I got her and the timing seemed wrong So... I pulled the head new valve guide seals lapped the valves. All back together, I had a few problems with the injector wiring (bad rott) but got that under control got her started YEA!!! then no go after much tring I finaly pulled the valve cover nd found the shiny link 5 to 6 theeth off the mark??? I'm buying a new chain and a new thensioner but the old ones did'nt seem all that bad??? Any Tips Tricks ect???? Its hard to believe the chain could jump so much????


Bob

 

These chains don't jump...

You're problem lies elsewhere. If the chain is off the mark, somebody put it there.


Rod.

 

My first zcar 1980 auto 280zx

the timing chain slipped 5/6 teeth the chain did'nt seem streched. The tensioner was a little groved but seemed to have good action. I ordered a new chian and tensioner hopefully this will help clues????

Thx

 

(merged threads)

 

No! If the chain is set on the marks and then the engine is rotated a few times, the marks wont line up! Ive tried it. Occasionally they will, but it will take many many crankshaft revolutions. I would say your problem is electric or fuel. Make sure you have fuel preassure, and check AFM, Dizzy, All connectors, and check for vacuum leaks. If the Dizzy is worn enough it will eat itself, thats why it has teeth.

 

ok I thought it wierd that the chian would do that Tommorrow i'll recheck And if all is ok i'll cancel the chain ect... Ok now to show my ignoance what's a dizzy ?

 

dizzy= distributor

 

now you said you pulled the head right? did you build the little wedge to keep the chain from coming off the bottom sproket? and also, yes the marks wont line up unless your at tdc, you can easily check that by looking at the rocker arms, if both valves are up, and you crank marks at 0, then your marks should line up.

 

Not only did I pull the head but the timing cover also. This has been a 2 year project for my sons first car. And as we all know it never goes as fast as we would like. The chain is per the book and after I rotated the engine a few more times the marks lined up GOOD! I was not looking forward to pulling the front coveragain. I'm going back to square one and check everything... wish me luck

Thanks for the info
Bob

 

Thanks for all your help. I fond my problem was the afm. The cover had been off and the spring was very loose. I was just starting to get it to run, and had just ordered a air fuel gauge when the number 4 exhast valve broke while the engine ws idling....the head should be ok with a little work but the piston is trash... Now I have to deide her fate... Thanks again


Bob

 

its not too hard nor expensive to do that, prolly 500 bucks, but its up to you, and hope you keep it. specially after all this time