I had the same problem and it was my spark plug wires, current was escaping and when I mashed on the gas the engine hesitated. Check you spark plug wires and make sure current isn't escaping, if they are change them.

Thanks Dodgeman, and yes I mean the rear axle assembly. I am using the vehicle for normal everday driving so I guess the 4-forward will work. What can I do to take off the strain from the clutch an engine? I'm from Trinidad and the 5-forward is really hard to fine, as a matter of fact a lot of mechanical parts are becoming difficult to fine in my country. But I'm determine to keep my Datsun and have it going, even if it means using other parts. I've been looking for the rear axle assembly for a while now and I finally found a place that have both the complete rear axle assembly for the B210 and the B310, and they are both used from Japan. My only query is which one to buy, because the B210 is spring leaf and the B310 is coil spring. If I buy the B310 will it work up on my B210. what is your recommendation since I'm running an A15 engine.

if the timimg is not set properly, will this cause the engine to burn more gas? Also I installed an Arospeed open end filter, will this filter cause the engine to burn more gas since more air is going to the carburator or will I get a better performance as well as better gas milege?

Thanks, but in my country it is very hard to get the 5-forward, I've been looking for it for a while, but no luck yet. Ok if I use the B310 back end, how will I cater for the coil springs or can the spring leaf on the B210 work on it?

I have the 1975 B210 120Y model with an A15 engine and a 4-forward gearbox. My diff is really damaged, and I want to replace it. I am getting the original B210 complete back end as well as the complete B310 back end to buy. The problem is I don't know which one to buy. I know that the original B210 will work, but since I have an A15 engine the diff may give out again. Does anyone know if the B310 complete back end will work on the B210 120Y or will I have to do some modifications? Secondly I don't know if the B310 model came with coil spring or spring leaf. If anyone can help me I'll really appreciate it. Thanks.

I really need some help with the timing on my A15 engine, I can't seem to get it right. Does anyone have a service manual for the A15 engine or knows the correct timing for the A15 engine. Thanks.

I have a 1975 Datsun 120y Model B210. I changed the original A12 engine with an A15. The engine works great, but I've already damaged the original 4 forward gearbox. I tried to get the 5 forward, but its really hard to get in my country (Trinidad). So, I ended up buying back a 4 forward, but when I shift in fourth the engine calls for another gear. Well my other problem is that my diff is completely damaged, It has a serious "Backlash". What I would like to find out is which diff could work on this model car. I'm not interested in changing the entire rear end, just the Diff. Could anyone who has done this before or has an idea as to how to solve this problem please respond, any help will be greatly appreciated.