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Rhino13

Snake pit - rhino built

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Hey all, I am new here but have owned a few 720's in the not so distant past. A few days ago I went and picked this up for $800, runs and drives, has no engine, tranny, or rear end noise, 150,000ish miles, and even has good tags! It needs new seats, and my lady really likes the idea of a bench, so thats what Ive got my eyes out for. I'd like to get a 620 bench in good condition.

The plan is to fix him up with a few things it needs, such as power steering pump and grille (that adds 10hp right?), make it more comfortable with the seat and a stereo, then daily it until I have enough money to drop it.

Plan is to drop it about 2", get new rubber, get new straight bumpers and re-hang new fenders, then get a "cheap" tape and spray paint job, and maybe do an exhaust if anyone can point my in the direction of something that won't sound like a little fart machine.

I will upload more pictures tomorrow once I get my internet booster set up and don't have to wait 30 minutes for a picture to upload.

 

IMG_20150206_183137_zps8ba0978c.jpg

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Welcome to ratsun. It sounds like a good build plan but I really only saw a couple questions.

 

2" drop - put two inch blocks in the back and let the torsion bars down in front. Torsion bar adjustment is covered ad naseum on this forum and on you tube.

 

Exhaust - you probably won't notice the the engine waking up a whole ton, but mandrel bent 2" or 2.25" at the most is plenty for that engine. Talk to a muffler guy and see what mufflers they like. Flowmasters are good, thrush can be ok, and there is always magnaflow.

 

There is a down side to a bench in a kingcab, it will make it difficult, if not impossible to gain access of any kind to the rear. But if that doesn't matter, then go for it. I don't know about a 620 bench, but I believe the 720 bench should bolt right in, even in the king cab.

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The Z24 is 50K overdue for a blown head gasket. Time to re-torque the head bolts. Start with a cold engine, loosen one bolt and immediately tighten to 60 ft lbs then move to the next bolt. One at a time loose and in any order you like. This is recommended by Nissan at every tune up. This will refresh the clamping force on the gasket and prevent it blowing out. The Z24 is well know for doing this.

 

Stock exhaust down pipe is 2" but get a turbo muffler that is well 'padded' inside to remove/dampen annoying raspy sounds. You can also add a straight through 'cherry bomb' type on the tailpipe to mellow it out even more.

 

The drive train may be quiet now but unless you know what has been maintained on it, better to change the fluids now.

 

 

 

To confirm... transmission and transfer case oil is GL-4. Differential's oil is GL-5. It's important that GL-5 NOT be used in a Nissan transmissions or transfer cases.

 

Engine oil these days has a controversy about how much zinc additive ZDDP has been reduced in it and how well it protects our older 'flat tappet' engines. The ZDDP level 30 years ago was much higher than it is today and has been steadily reduced because today's roller rocker cams don't need it and it ruins the catalytic converters. Good or bad you can still run higher levels by using Shell Rotella T or Chevron Delo 400. Both are light diesel 15w40 oils. No you don't have to dump your out. Maybe just figure out what you want and change it at the next oil change.  Do NOT use fram oil filters they are crap and cheaply made. NAPA Gold, WIX and a few others are far superior in build and filter quality.

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Thanks for the welcome Lockleaf. I plan on doing torsion bars up from and blocks in back. Will the camber be way off once I crank down the torsion bars? And will I get ~2" of drop out of them? I'm waiting on an alignment right now because most of this is in the near future, so highway driving gets risky sometimes!

I plan on welding the exhaust up myself, and I'll probably just go with a cherry bomb like datzenmike mentioned, and have it dump out the side in front of the back wheel.

I think 520, 620, and 720 all have the same bolt pattern. Don't quote me on it, but I remember someone telling me that. I plan to keep tools in the back, so I'm going with a bench if I can find one in decent shape. Unless anyone knows of a newer car I could easily swap a bench out of for more comfort?

 

Thanks for the helpful info datzenmike. A few questions though. When re-torquing the bolts, is there a specific order I should go in? And am I reading correctly that using Delo 400 diesel oil is good for these old gas engines too? I used to have an 82 diesel 720 and Delo 400 was all I used.

 

I'll take more pictures tomorrow morning if it's not raining. The seats are pretty hilarious, both backs move freely, and the passenger seat also doesn't lock on the tracks so my lady has been getting a leg workout everyday ha ha

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Thanks for the welcome Lockleaf. I plan on doing torsion bars up from and blocks in back. Will the camber be way off once I crank down the torsion bars? And will I get ~2" of drop out of them? I'm waiting on an alignment right now because most of this is in the near future, so highway driving gets risky sometimes!

Any raising and lowering will alter the camber and the toe-in slightly. Adjust height then align one time.

 

and I'll probably just go with a cherry bomb like datzenmike mentioned, and have it dump out the side in front of the back wheel.

What I said was...

 

Stock exhaust down pipe is 2" but get a turbo muffler that is well 'padded' inside to remove/dampen annoying raspy sounds. You can also add a straight through 'cherry bomb' type on the tailpipe to mellow it out even more.

 

I do NOT recommend just a cherry bomb straight through 'muffler'. Thsy sound like shit, but added to a turbo muffler will mellow it out even more.

 

 

Thanks for the helpful info datzenmike. A few questions though. When re-torquing the bolts, is there a specific order I should go in?

The Z24 is 50K overdue for a blown head gasket. Time to re-torque the head bolts. Start with a cold engine, loosen one bolt and immediately tighten to 60 ft lbs then move to the next bolt. One at a time loose and in any order you like. This is recommended by Nissan at every tune up. This will refresh the clamping force on the gasket and prevent it blowing out. The Z24 is well know for doing this.

 

And am I reading correctly that using Delo 400 diesel oil is good for these old gas engines too? I used to have an 82 diesel 720 and Delo 400 was all I used.

Engine oil these days has a controversy about how much zinc additive ZDDP has been reduced in it and how well it protects our older 'flat tappet' engines. The ZDDP level 30 years ago was much higher than it is today and has been steadily reduced because today's roller rocker cams don't need it and it ruins the catalytic converters. Good or bad you can still run higher levels by using Shell Rotella T or Chevron Delo 400. Both are light diesel 15w40 oils. No you don't have to dump your out. Maybe just figure out what you want and change it at the next oil change. Do NOT use fram oil filters they are crap and cheaply made. NAPA Gold, WIX and a few others are far superior in build and filter quality.

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Thanks for the reply datzenmike. It was late so I passed over a few of your answers. I meant to say cherry bomb/turbo. I had a friend that got into putting cherry bombs on all of his cars and it makes every car sound like a ricer Honda.

 

Now a few more questions before I do a majority of the work this upcoming week...

What are causes of inconsistent idle? I always start with pumping the gas for the choke and it always runs fine, but when driving around town it idles very low when coming to a stop, but idled perfect when coming off the highway or any faster road. Sometimes it's always fine, so I'm thinking carb cleaned and all new vacuum hoses, but want a second opinion.

 

My gas gauge and temp gauge work intermittently, but have stopped altogether the last three times I've driven. Electrical problems always stump me so I never have any idea where to start looking, and would rather not take the dash apart if it's not necessary.

 

And lastly about lowering. Do most people get new lower riding shocks? And if so what are some good brands? I came across a Belltech set, but have no experience with these type of shocks.

What's a good size wheel/tire to run on a 2" drop? I'm not really a fan of big wheels and small tires, so I think I might go with a white wall on stock 620 rims with the big hub caps, but I'd also like some input to see my options.

 

Any help is appreciated

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Next time it's warmed up take the top off the air filter and takes a look. The choke plate should be fully open. The plugs are probably cleaned after the highway and maybe sooted up around town. The choke being part on might do this. Also look at the sight glass on the front of the carb. Fuel level should be at or very near the dot on the round glass.

 

If they both quit together then the regulator is suspect. The temp and the gas gauges run off the same voltage regulator located in one the the gauges. (I forget which one) Looks like this, inside the cluster. Just get some fine sandpaper and fold into a thin strip. Open and close the points on it and draw the paper through to clean them.

 

720fueltempgaugevoltregulator002Large.jp

 

A 2" drop can be done by adjusting the torsion bars on the front. Just type "torsion bar lowering" into the search for a detailed description. Keep in mind that the steering toe in and camber will be affected to some degree and a corresponding adjustment or alignment needed to correct this. Not adjusting will affect handling, steering and tire wear. For a 2" drop the stock shocks will be fine.

 

The rears are easy to do by replacing the rear U bolts with longer ones and slipping a 2" block or spacer between the axle and the top of the leaf spring pack. This may throw out the drive shaft angles and cause some unwanted vibration so shims might be needed under the front or rear of the block to correct this. Lowering the rear with blocks has zero effect on shock length, so no worries there.

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Got the idle worked out, there was a nut that fell down the carb and got locked into place on a swivel so it would sometimes hold the plate open a little.

 

The relay was the culprit, and sanding it worked perfect. However, once I reassembled everything the blinkers stopped working. I did take one of the dash lights out to replaced it, and tried putting it back in with no luck. Both fuses are good. Headlights work, both normal and high beams, and flashers work normally. It's just the turn signals.

 

Thanks for all the lowering info, I've got a pretty good idea of what I'm up against and plan to tackle it within the next week.

 

Also is there a place where people can buy and sell parts on the site? I'm in need of a few small things like a grill with Datsun logo, sun visors, a black drivers side fender, Datsun fender logos, front bumper, 1 reverse light housing, tachometer, and speaker covers for the walls under the dash. If anyone can direct message me with parts or point me in the direction of a cheap source, I'd greatly appreciate it. I live in the Eugene area of Oregon.

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And my apologies if posting about buying/selling is a no no.

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Rhino, at the top of each Ratsun page, there is a menu. In that menu is a "Classifieds" section. There you go!

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Thanks petercscherer!

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Any help on the blinker situation is greatly appreciated.

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Any help on the blinker situation is greatly appreciated.

I'd pull your column cover off and make sure the terminals to the actual switch aren't loose or rusted.

~Peter

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try cycling your hazard switch back and forth and make sure it stops in the right place....ive read on here its problematic and messes up blinkers...good luck

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Thanks Peter, I did pull the column cover and checked all connections, but thank you for the input.

 

Thanks bilzbo, you got it spot on! I moved the switch a few times and found that if I turn it off slowly, the blinkers work fine. Very glad it was so easy...

 

I've got a few more lowering questions now... What is a good size block to use in the back if I'm running 195 tires up front with dropped torsion bars (not reindexed, about 2" drop) and 205 tires in the rear? I was thinking 2" blocks but I've been reading that a lot of people do 3" to level the ride height, just want some first hand experience from people who have this set up.

I'm thinking of just painting my stock 14 rims black and getting chrome 620 hubs, but I'm curious about going with something wider to increase handling a bit. What's the widest I can go without having to roll my fenders?

Ideally I'd like them to just barely stick out or be flush if possible.

 

Thanks

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Finally took a few more pictures today after cleaning the last few days. Installed a bench seat from an 89 hardbody and some Sony Xplode speakers in the doors. There was already holes cut, and the stock speaker bezel cover is trash on both sides so I'm going to redo them without the mesh part for the speaker.

 

IMG_20150218_171930186_HDR_zpsd601d963.j

My lady got me that snazzy seat cover. I always liked that Mexican style blanket that everyone seemed to have covering the bottom of the bench in old Fords.

 

IMG_20150218_171952045_HDR_zps243d2519.j

I've vacuumed twice now, but the dirt driveway always wins.

 

IMG_20150218_171904176_HDR_zpsf1942384.j

 

IMG_20150218_171942239_HDR_zps7c6b6990.j

 

I'll get some exterior pictures once I give it a bath and pop out a few dents.

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Any help on the blinker situation is greatly appreciated.

 

I see you fixed them. I spent an hour one Saturday fixing a friend's flashers. And yes it's the design of the 4 way flasher switch. It should disconnect the signals and connect the 4 ways. When turning the 4 ways off it travels too far in the off position and actually disconnects them again. The trick is to move the switch slightly toward the 4 way ON position. This is a very common problem on the 720 buy an easy fix.

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Yeah, got it figured out, but thanks for the reply and the tip. I was very happy to find out it was so easy. Electrical is not my strong point.

 

I was putting off under the hood mostly because the fluid levels were perfect, no leaks, no engine noise, and the only "Jerry rigged" thing in the bay is a Powerade bottle for the coolant overflow.

However, the power steering pump pulley is loose and rattles at low rpms. When the truck is off it only has inward and outward play. The belt was loose to the point that I was impressed it was even working, so I tightened it up. It still has a little play in and out, but the shaft bolt it tight. I'm guessing it needs a new pump, but I thought I'd ask in case it's a bearing or something that can be changed because the pump works fine otherwise. Only get a little squeal every once in a while from a stop.

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I like you seat cover!

Thanks! They make them for buckets too.

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So just curious, whats everyone's opinion on Lucas cylinder lubricant and Sea foam? I've seen people use them but never have personally and wanted some opinions.

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Shouldn't need it if everything is working okay. It's basically a solvent that dissolves engine deposits. You want to remove carbon build up?...

 

Two things needed are hearing protection and a tall boy full or water.

Take air filter off. If you have a header disconnect the rest of the exhaust pipes from it.

Warm engine up, get it hot, really hot. Cardboard in front of rad hot. 

When temp gauge is 3/4 or high in the normal range you are ready.

Rev engine well up and start trickling the water down the carb.

Engine will slow down so add throttle to keep revved up.

More throttle and more water!

Exhaust will steam... a lot, so do outside.

Temp gauge will drop to normal and even lower, so let warm up again and repeat.

 

What you are doing is steam cleaning the combustion chambers. The sudden cooling will shrink and crack off the carbon layers and the flakes will pass through the exhaust ports and out. If you have ever replaced a blown head gasket that leaked coolant into one or more cylinders you have seen first hand the cleaning power of super heated steam on the combustion chambers, the valves and the piston tops.

 

If you place cardboard under exhaust outlet you will see the shit that came out.

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Used to do this on my 79 Harley Low Rider.  New off the show room floor it would carbon up and start pinging.

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It was great to meet you yesterday at the work party for the Canby truck . 

 

The next generation of datsun lovers is alive and growing !

 

 

P.S.  you have to take pictures of it dented also ,  it's a lot more fun for us to see how far it's comes .  Cause you know it's all about us & Pics :poke:  

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