Rasp933 Posted May 20, 2018 Report Share Posted May 20, 2018 Hi. Did anyone had a problem where the valve lash nuts won't open? Need inputs guys.. Quote Link to comment
racerx Posted May 20, 2018 Report Share Posted May 20, 2018 You mean you can't loosen the nut that tightens or the one that adjust the valve? 1 Quote Link to comment
Rasp933 Posted May 21, 2018 Author Report Share Posted May 21, 2018 Both.what am I doing wrong here Quote Link to comment
captain720 Posted May 21, 2018 Report Share Posted May 21, 2018 Not using a big enough lever? JK they shouldn't be that tight so be very careful and consider soaking then in a non abrasive loosening substance. Quote Link to comment
datzenmike Posted May 21, 2018 Report Share Posted May 21, 2018 Bottom part is screwed into head and stays there. Top part with the ball .... ....screws down into the bottom part to set the valve lash. The nut in the middle is tightened down to hold the setting. What can happen is the valve seats wear down, earlier ones were bronze and needed the lead in gas to lubricate them. Non leaded gas wears them out faster. The valve then burrows up into the head and the pivot post bottoms out and runs out of adjustment. Eventually you will need to replace the seats with the later hardened ones, but you can get more adjustment by grinding the adjustment nut thinner. Might get you through the winter when you don't want the car off the road. Comparing both nuts. Bottom one is uncut.This will allow the top part to set deeper into the bottom. You may even have to grind a couple of threads off the bottom. 2 Quote Link to comment
Doctor510 Posted May 21, 2018 Report Share Posted May 21, 2018 Both.what am I doing wrong here You need to loosen only ONE, the 17mm one. Use the longest 17mm open end wrench you can or buy a 17MM "CROW'S FOOT". I believe that Snap on still sells the special wrench that works super. Quote Link to comment
racerx Posted May 21, 2018 Report Share Posted May 21, 2018 If you have never adjusted valves, may want to go on you tube, several valve adjust on datsun. Visual will give you a better idea. 2 Quote Link to comment
Rasp933 Posted May 21, 2018 Author Report Share Posted May 21, 2018 I guess these nuts were fused together by heat Quote Link to comment
john510 Posted May 21, 2018 Report Share Posted May 21, 2018 I guess these nuts were fused together by heat Not likely.Get a better wrench. Quote Link to comment
datzenmike Posted May 21, 2018 Report Share Posted May 21, 2018 Lefty lucy Righty tighty Quote Link to comment
banzai510(hainz) Posted May 21, 2018 Report Share Posted May 21, 2018 YOur have to break the 17mm first to give it soem slack then while holding the 17mm you loosen the 14mm and adjus to what you need then while holding the 14mm not to move you tighten the Jam nut 17mm . then it will hold Quote Link to comment
Rasp933 Posted May 21, 2018 Author Report Share Posted May 21, 2018 This stuff can be really tricky Quote Link to comment
Rasp933 Posted May 21, 2018 Author Report Share Posted May 21, 2018 Thanks for messaging guys .you all are the best 1 Quote Link to comment
racerx Posted May 21, 2018 Report Share Posted May 21, 2018 Book says to adjust hot but you can adjust cold. Very hard to adjust while hot for first timers. Quote Link to comment
racerx Posted May 21, 2018 Report Share Posted May 21, 2018 Also write this down on a big piece of paper, E I I E E I I E. As you adjust one valve cross it out. E is for exhaust and I is for intake and as mentioned earlier go on YouTube and see Datsun L series valve adjust, it makes more sense when you see it vs reading it. Good luck. 1 Quote Link to comment
d.p Posted May 21, 2018 Report Share Posted May 21, 2018 You need to loosen only ONE, the 17mm one. Use the longest 17mm open end wrench you can or buy a 17MM "CROW'S FOOT". I believe that Snap on still sells the special wrench that works super. This the tool? https://www.ebay.com/p/Snap-on-17mm-1-2-Drive-Valve-Adjustment-Tool-S6014/1926243914?iid=302725178525 Quote Link to comment
racerx Posted May 21, 2018 Report Share Posted May 21, 2018 You can use that but I actually cut mine, length wise, battery got in the way. I also shaved the 14 mm, nut is easier to get to. Quote Link to comment
DanielC Posted May 21, 2018 Report Share Posted May 21, 2018 "Book says to adjust hot but you can adjust cold. Very hard to adjust while hot for first timers." Adjust cold. then recheck after engine is hot. Quote Link to comment
don51o Posted July 7, 2018 Report Share Posted July 7, 2018 I set them .001 tight-cold. then check hot. seems quite close. (street perf. cams). Banzai510 has the adjuster answer Quote Link to comment
don51o Posted July 7, 2018 Report Share Posted July 7, 2018 to remove rocker arms where "unlocking" jam nut doesn't work, get/make strong rod (I ground down end of allen wrench) that fits into rocker oil hole and lever towards cam. rocker heel will rise off pivot and you swing to side: free rocker. No need to touch adjustment. Remove rocker arm spring retainer and you can use socket and big bar to remove pivot socket. Quote Link to comment
Stoffregen Motorsports Posted July 7, 2018 Report Share Posted July 7, 2018 On 5/21/2018 at 8:42 AM, d.p said: This the tool? https://www.ebay.com/p/Snap-on-17mm-1-2-Drive-Valve-Adjustment-Tool-S6014/1926243914?iid=302725178525 Yes, that's the tool. Those jam nuts can be very tight and using the Snap-On crow's foot may be the best way to get them loose in the car (on an engine stand is a lot easier). Quote Link to comment
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