Son_of_a_Nun Posted January 14 Report Share Posted January 14 1980 Datsun 720 4x4. Basically in any gear, after coasting in gear. I get a fairly consistent hard throttle response. The accelerator is fine/smooth. It's the reengagement of the fuel/throttle that causes a kick of sorts. Any thoughts as to what could be worn or damaged? Quote Link to comment
datzenmike Posted January 14 Report Share Posted January 14 It bogs when stepping back into it? 1/ Accelerator pump is not working. Quote Link to comment
Son_of_a_Nun Posted January 15 Author Report Share Posted January 15 Not quite. It’s more of like a gear box issue. Or at least feels like it’s possibly the differential? It’s more of a kick in the pants. Quote Link to comment
datzenmike Posted January 15 Report Share Posted January 15 Check the two engine and one transmission mounts. Quote Link to comment
Son_of_a_Nun Posted January 15 Author Report Share Posted January 15 Great point. I’ll inspect them tomorrow. Thanks Quote Link to comment
Crashtd420 Posted January 15 Report Share Posted January 15 15 hours ago, Son_of_a_Nun said: 1980 Datsun 720 4x4. Basically in any gear, after coasting in gear. I get a fairly consistent hard throttle response. The accelerator is fine/smooth. It's the reengagement of the fuel/throttle that causes a kick of sorts. Any thoughts as to what could be worn or damaged? I generally assume manual transmission... any chance this is an automatic? Quote Link to comment
datzenmike Posted January 15 Report Share Posted January 15 My Charger had a loud bang and would shake the car when stepping on the gas after slowing. It was an automatic so it always had a slight load on the driveshaft when driving but it was like there was slack, a lot of slack in the drive train that when taken up would bang. Eventually I found that I could turn the differential almost a 1/4 of a turn between coasting and under load. I pulled it and the pin that held the spider gears had pounded a large slot in the carrier that holds the ring gear. In fact it had already cracked the casting and was on the verge of breaking out. 1 Quote Link to comment
Son_of_a_Nun Posted January 15 Author Report Share Posted January 15 It’s a manual. Interesting. I have a funny feeling, It might be the differential as well. I’m gonna start with the motor mounts though. I should be an easy swap out and probably needs to be done anyway. 1 Quote Link to comment
datzenmike Posted January 15 Report Share Posted January 15 You don't have to swap mounts for new, just check and eliminate them as the cause. I've learened the hard way not to fix what isn't broken. As to the differential, place in neutral and try turning the drive shaft at the differential pinion. Normally it will rock back and forth through the normal gear lash maybe 1/4"-1/2". In my case the pinion mate shaft had pounded sideways almost all the way through the carrier casting. 2 Quote Link to comment
Ranman72 Posted January 17 Report Share Posted January 17 check all ujoints and drive shaft bolts too Quote Link to comment
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.