Just got a 720 4x4 and brought it home. I took it out for a drive and noticed I lacked power and it was missing slightly. It seems someone before me had problems but only made things worse. It was wired with the firing order 1234 at TDC it was hitting on #4 ex so I got it to TDC, put the wires in proper order and now it will barely run at all! My question is...what if any reason would it now not run properly or close to it. Is it possible I have a faulty distributor??Thanks in advance for any ideas.....shay
Modified by [email protected] at 6:01 AM 3/27/2009

My truck is a 1982 720 4x4...z22 motor....it is doing the same thing....slow slow like the cat. converter is clogged or something...and today it has a skip at idol...my motor only has 71,000 miles on it with a brand new carb and plugs...so im intrested in seeing what ppl write back in this post...

wow...my 720 is an 84 w/ 72K - no cat -new weber carb-fuel pump-plugs&wires..etc.

There's definitely something wrong there. 1234 firing order is way out; I'd say your cam timing is probably out. Check the marking on the cam timing plate and the notch on the chain sprocket at TDC. There's three notches on the sprocket that alter the cam timing by 2 degrees. Get the one where the notch and the marking match as closely as possible.

thanks....I think it has aftermarket cam

A shifty distributer can cause this in many other cars I have worked on. I am new to anything post 70's and also Japanese, but I would look into it. The thing can slap around a bit due to it's wear and never get good timing. I have also been able to put a distributer in 180 degrees out of place and get the vehicle to run poorly until I figured out what I had done. Switched it and off she went. Again, not a Datsun/Nissan, but. Looking at some tech pics could help you figure this out. This could be something only I could do on a late night of wrenching, however.

The vacuum hose thing comes up very often around here too. Seems like another good place to go. It has moved to second on my list, after an oil pan gasket/fluid change. I plan on just taking every piece out and replacing them one by one. I figure it should be a leisurely afternoon if I am prepared with plenty of hose.

Had a similar problem when I got mine. Is it the J16 engine, if so your cam/valve timing is out, if it misfires and backfires also there is carbon build up on the valves and combustion chamber. Take off the front cover, put the No 1 cylinder on TDC and reset the cam one tooth to the right to advance the timing or one tooth to the left to retard it. It takes a little time but in the end it will run fine. Once the power is up, ilde up the engine to about 1100 rpm and spray into the carburettor with a spray called BARS TECH. This will loosen the carbon. Carry her for a run and see the difference. hope you dont get caught speeding,will check daily for your final run feed back.

Eddie