banzai510(hainz) Posted March 23, 2019 Report Share Posted March 23, 2019 I had 2 blocks built and the bearing size was still STD size. 1even with 200k Miles on it. make sure to Gap the rings make sure your oil pump still has oil in it when you put things back together 3 Quote Link to comment
Genaro Posted April 1, 2019 Author Report Share Posted April 1, 2019 (edited) Ok, after waiting for the parts to show up, im finally ready to put things back together... I hope i dont mess it up! As Mike suspected, there is one rod bearing that haves a scratch all the way around, luckily the crankshaft isn't damaged. Edited April 1, 2019 by Genaro Add info 3 Quote Link to comment
Crashtd420 Posted April 1, 2019 Report Share Posted April 1, 2019 One bit of advice, use plenty of assembly lube and oil..... but be careful assembly lube is sticky..... I almost messed up when I was loading my pistons .... one of the bearing shells came loose from the rod and stuck to the crank as I was trying to install the rod cap.... but I think that was because of my rods, i upgraded mine, it looks like yours should go together a bit smoother...... as you install things rotate the crank.... it should always turn smooth, but the amount of resistance will increase with each piston and obviously from the head.... And I'll share a painful tip make sure there are 2 dowel pins in the front cover.... they align the oil pump shaft... I lost one and I almost had a huge issue.... crank bound up solid.... luckily I found this while turning it by hand..... 2 Quote Link to comment
Genaro Posted April 1, 2019 Author Report Share Posted April 1, 2019 (edited) 44 minutes ago, Crashtd420 said: One bit of advice, use plenty of assembly lube and oil..... but be careful assembly lube is sticky..... I almost messed up when I was loading my pistons .... one of the bearing shells came loose from the rod and stuck to the crank as I was trying to install the rod cap.... but I think that was because of my rods, i upgraded mine, it looks like yours should go together a bit smoother...... as you install things rotate the crank.... it should always turn smooth, but the amount of resistance will increase with each piston and obviously from the head.... And I'll share a painful tip make sure there are 2 dowel pins in the front cover.... they align the oil pump shaft... I lost one and I almost had a huge issue.... crank bound up solid.... luckily I found this while turning it by hand..... Thanks Crash! Every advice is welcomed...i am a total newbie in this trade...! I work in industrial plants as a field commissioning & start-up technician, so i know how things should work but not always how they do they work in deep...hahaha...! Yes! Pins for the front cover are there, will keep an eye on them .. Im reading about assembly lube, i though it was only oil to be used... Manual says to use engine oil, but i see that a bit more of sticking is good to keep things in place while assembling and also in the first rotations before real run...Good tip! I was reading a guy that says that before running the engine for the first time, it is good to remove the spark plugs, coil cable and crank it like that for a while, until you see the oil low pressure switch turns off.... Sounds reasonable, isn't it? Thanks again! Edited April 1, 2019 by Genaro Mispell 2 Quote Link to comment
Genaro Posted April 1, 2019 Author Report Share Posted April 1, 2019 (edited) Luckily for me, removing the engine made me see that the clutch disc is shot , was rubbing rivets against pressure plate ... New kit is on its way... 225mm 24 splines...it was hard to find the right one, most of parts sellers here have the small one that goes into cars, not trucks... Edited April 1, 2019 by Genaro Add info 2 Quote Link to comment
Crashtd420 Posted April 1, 2019 Report Share Posted April 1, 2019 6 minutes ago, Genaro said: Thanks Crash! Every advice is welcomed...i am a total newbie in this trade...! I work in industrial plants as a field commissioning & start-up technician, so i know how things should work but not always how they do their work in deep...hahaha...! Yes! Pins for the front cover are there, will keep an eye on them .. Im reading about assembly lube, i though it was only oil to be used... Manual says to use engine oil, but i see that a bit more of sticking is good to keep things in place while assembling and also in the first rotations before real run...Good tip! I was reading a guy that says that before running the engine for the first time, it is good to remove the spark plugs, coil cable and crank it like that for a while, until you see the oil low pressure switch turns off.... Sounds reasonable, isn't it? Thanks again! The assembly lube is designed to stay around till the oil gets there during startup.... just oil would be ok I think in your case because your gonna be starting it almost immediately .... the motor is not gonna be hanging around waiting...... And yes cranking the motor and priming the oil system is a good idea.... you could even prime the oil with a rod through the distributor hole, that gets the oil flowing before all the extra rotating, but that's basically why the assembly lube gets used so you dont have to do all that.... I did that every other week because I had about 6 months between finally assembly and startup...... 1 1 Quote Link to comment
datzenmike Posted April 2, 2019 Report Share Posted April 2, 2019 The main bearing caps all have arrows, point them towards the front. When you are ready to torque the center thrust main bearing cap shove the crank forward as far as it will go then tighten the bolts. Torque from the center outwards in at least two stages. Do all in the following order to 20 ft pounds. Then a final finish torque to 35-40 ft pounds. RAD 7....8 3....4 1....2 thrust bearing 5....6 9..10 Flywheel The rear cap also has side seals that must be installed correctly Make sure you lube the rear oils seal before installing so it does not start up dry. 3 Quote Link to comment
Genaro Posted April 2, 2019 Author Report Share Posted April 2, 2019 (edited) Thanks for the advices, Mike! Two questions in one picture, guys... - Is this manual ok? - Could be a problem that the new bearing haves the little hole slightly bigger than the original's bearing one? Thanks and have a nice week! Ps: actually is almost double the size of the hole 🤔🤔🤔 Edited April 2, 2019 by Genaro 🤔🤔🤔 2 Quote Link to comment
datzenmike Posted April 2, 2019 Report Share Posted April 2, 2019 Shouldn't matter, just lets in the oil. 3 Quote Link to comment
banzai510(hainz) Posted April 2, 2019 Report Share Posted April 2, 2019 (edited) make sure to prime oil pump before START. or pump oil to the oil pump using a hose. I prime my carburetor so gas squirts in and then just START it. . the oil pressure should be there in 15seconds.. I pour oil on the cam and rocker arms right before start also Edited April 2, 2019 by banzai510(hainz) 3 Quote Link to comment
datzenmike Posted April 2, 2019 Report Share Posted April 2, 2019 I should imaging Nissan has assembly lube on all moving parts and they just start them up and go. Shrug. I worked for GM in the mid 70s and did spend a day working at the end of the truck line where they are started and driven to the parking lot. The probably primed the carbs but it took about 5? seconds to get them going. 2 Quote Link to comment
Stoffregen Motorsports Posted April 3, 2019 Report Share Posted April 3, 2019 I never prime a Datsun before firing, but I do pack the pump with Redline assembly lube. This helps the pump create suction to get the oil flowing. Just fire it and watch the psi gauge. It should build pressure within about 5 seconds. 3 Quote Link to comment
Stoffregen Motorsports Posted April 3, 2019 Report Share Posted April 3, 2019 Maybe I missed it, but you are using new bearings, right? The ones in the pics at the top of this page aren't in great shape. See the copper??? 2 Quote Link to comment
Genaro Posted April 3, 2019 Author Report Share Posted April 3, 2019 Just now, Stoffregen Motorsports said: Maybe I missed it, but you are using new bearings, right? The ones in the pics at the top of this page aren't in great shape. See the copper??? Thanks for the oil pump advice! Yes, all bearings, piston rings, valves/guides/seals are new, i've just finished assembling the crankshaft with the pistons. Now starting to put together the head and chain.... 4 Quote Link to comment
Genaro Posted April 6, 2019 Author Report Share Posted April 6, 2019 Tomorrow i will put the engine back to his place... Cross your fingers with me! Hahahaha.... 4 Quote Link to comment
Crashtd420 Posted April 6, 2019 Report Share Posted April 6, 2019 Hard parts done..... nice job.... 3 Quote Link to comment
banzai510(hainz) Posted April 6, 2019 Report Share Posted April 6, 2019 I sometimes jack up the trans mission and have the engine mounts loose to help get my engine in my 521 as I angle it in with the water pump on and its a tight fit 2 Quote Link to comment
datzenmike Posted April 6, 2019 Report Share Posted April 6, 2019 Later '75 and up rad supports bow out for a larger rad and have more clearance. L16/18 L20B '75 and up 3 Quote Link to comment
Genaro Posted April 9, 2019 Author Report Share Posted April 9, 2019 Hi guys! First of all....BIG THANKS to all the people that helped me thru the process of diagnosing/fixing the engine....! Last night i started it for the first time, today im going to give it a try on the road. Any advice/suggestion on how to treat the engine for the first miles/kms will be greatly appreciated! 3 Quote Link to comment
Crashtd420 Posted April 9, 2019 Report Share Posted April 9, 2019 Just dont beat on it to bad for a little while...... When I broke my motor in we just drove it normal.... well it was on a dyno, but still .... we also let the motor compression brake a few times, i forget why but it was something to do with rings.... Nice work. . Very satisfying when things go as planned.... 3 Quote Link to comment
datzenmike Posted April 10, 2019 Report Share Posted April 10, 2019 Don't baby it. It's called BREAK IN not BABY IN. Avoid driving at steady speeds and excessive idling during the break in period, always be accelerating or decelerating. Drive it hard out on the highway. Accelerate full throttle from 30-60 in 4th and let slow by itself back to 30 and repeat 15-20 times. You want the new rings to be forced against the honed cylinder walls and wear themselves in to make a tight seal. Check the temp is not over heating and oil is full, watch the gauges. Hopefully you filled with cheap oil and change it and the filter after 100 miles and drive normally. Do NOT use synthetic oil. 5 Quote Link to comment
Crashtd420 Posted April 10, 2019 Report Share Posted April 10, 2019 6 hours ago, datzenmike said: Don't baby it. It's called BREAK IN not BABY IN. Avoid driving at steady speeds and excessive idling during the break in period, always be accelerating or decelerating. Drive it hard out on the highway. Accelerate full throttle from 30-60 in 4th and let slow by itself back to 30 and repeat 15-20 times. You want the new rings to be forced against the honed cylinder walls and wear themselves in to make a tight seal. Check the temp is not over heating and oil is full, watch the gauges. Hopefully you filled with cheap oil and change it and the filter after 100 miles and drive normally. Do NOT use synthetic oil. And Mike for the win..... I knew there was more to it...... 2 Quote Link to comment
datzenmike Posted April 10, 2019 Report Share Posted April 10, 2019 Previous to the 60s you did have to baby engines during the crucial first 500 miles. Since then engine parts and oils are such that a faster break in is advised. Avoid low RPM lugging and too much idling but do not red line it either. You want to work the engine to seat the rings. If you can't get out on the highway use 3rd gear and rev from 2k to 4K under load but let the vehicle slow by itself in gear no brakes. Don't worry about idling at the lights just don't leave idling in the driveway. Just drive it and make it do some work. 4 Quote Link to comment
Genaro Posted April 10, 2019 Author Report Share Posted April 10, 2019 Excellent tips guys! Thanks a lot...! I used it yesterday and no problems at all. Engine runs much smoother and quieter than before... Im using Shell Rimula R4 X 15W40 mineral diesel oil...ZDDP supposed to be 1250 ppm. Idling oil pressure is at 38 Psi constant at normal coolant temperature. (Temp sender stopped working today...what a nice moment to fail... It was bad grounding only) Engine hasn't been "tuned" at all...i dont have a lamp to check the timing and i dont have the knowledge for adjusting the carburator, i'm reading about that... But i've put everything back as it was and bum.... It' s running...hahahah! Sorry if it sounds too amateur for some of you! What about head re-torque after some mileage? I was reading a thread here on Ratsun and one guy says : "After the engine has been warmed up, ran and cooled down, recheck the torque. Check it again in about 100 miles. Recheck at the next oil change. By now, everything should have settled into place, and you will not need to recheck as often, but I think Nissan still recommended a head bolt check every 12,000 miles." Sounds reasonable to me, but again ...im not a mechanic! TXS ! 2 Quote Link to comment
datzenmike Posted April 10, 2019 Report Share Posted April 10, 2019 Head re-torque is not totally necessary, might have been in the '50s. The only engine that should be re-torqued once a year is the Z24 in the 720. There are not many things more exciting than assembling inert parts and have it start an run, pulling you and the vehicle down the road. I would check the hot valve lash and set the timing before adjusting the carb idle mixture and speed. You can set the carn now but you really should do it again after those other adjustments. Find the idle mix screw and the idle speed screw. Idle mix is on the valve cover side on the base of the carburetor. If standing leaning over the passenger fender to see it, the idle speed is to the left and more on the rear of the carburetor. Begin by turning the speed down as low as you can so changes are easier to detect. Turn the mix screw in (leaner) or out (richer) one or the other will improve or make the idle worse. Try 1/4 turns and wait a few seconds for any change. You may find there is almost one full turn where it runs good but drops off on either side. Just set roughly in the middle of the good. Try to find the strongest, smooth idle position. Likely the idle has gone up so turn it back down and repeat the mixture adjustment. You may need to perform this adjustment over a half dozen times to get it just right. When you have it idling strongly and can't improve on it and the idle speed is about 650-750 you're done. 3 Quote Link to comment
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