My 1971 521

[mainer311]

This L20b is going to be about as quick as the L16 now that it’s pushing 40lbs of brass adapters. 
 

2 oil pressure sensors, 2 water temp sensors. Might as well put a second speedometer on there, so you can check your speed while you’re checking your speed.

Edited February 14, 2021 by mainer311

[d.p]

At least it will look good doing it.  

[d.p]

Alright well @mainer311 was right about 1 thing, 2 water temp gauges are overkill. 

 

I am fine with oil pressure for obvious reasons but once I was done installing them I looked at the stock water temp gauge and looked at the autometer gauge and thought to myself "well that's redundant."  I still have the single hole thermostat housing installed and would have to take the Mikunis off to install the 2 threaded hole one and I really have no interest in doing that.  So it wouldn't even work if I wanted it to without switching the housing.  So rather than keep the water temp I figure I will just get a volt meter gauge instead...unless someone has a better recommendation?   I also ordered a matching autometer tach, been using a sunpro that @Crashtd420 graciously gifted to me years ago.  

 

 

 

Other car related news my wife got a new car, MB GLA45 AMG...pretty slick hatchback..AWD 375HP and 350ftlb of torque IIRC.  Makes me want to sell my BMW and get into a Mercedes, C63s or GLC63 or something along those lines.  MB interiors are miles ahead of BMW but I think BMW provides a better driving experience and MB has 0 manuals which is a bummer.    

 

[mainer311]

Manuals will soon be dead. It’s really a shame. The new Nissan Frontier doesn’t even have a manual option anymore. With all of these new DCT’s, shifting is obsolete. I think it makes people less connected to the car. 

[d.p]

My dad told me not too long ago that I too will grow tired of a manual and he is usually right more often than wrong.  Having driven my wife's GLA and about 4 other auto Mercedes over the past month and half I think I won't miss it all that much if I did get a new car.   ICE will be dead in our lifetime then it will be auto, electric self fellating cars for everyone.   

[datzenmike]

The stock temp gauge has no numbers but your after market one will be more accurate. However if the stock one runs at say 1/2 all the time then it only needs to read above or below to let you know something is wrong or out of the ordinary.

 

I remember when an automatic was a hot option but then the muscle car age happened and 4 speeds were hot. It was my experience that around 350 cu in the automatic began to equal the standards all things equal. Less skill was needed when racing and the automatic never missed a shift. Smaller V8s were terrible and a six stick could almost give them a race. Six and four cylinder automatics? forget them!

 

I like the idea of a paddle shift but that's as far as my interest goes. Today's cars put out a lot more hp also which makes an automatic less unappealing. 

[d.p]

Trying to figure out what to do with the block vent pipe and mikunis?  Can I just plumb the block vent directly to the valve cover pipe and call it a day? Or leave the block pipe venting to open air and run a small filter on the valve cover pipe (which I did on my l16)?  
 

what say ye??

[Crashtd420]

54 minutes ago, d.p said:

Trying to figure out what to do with the block vent pipe and mikunis?  Can I just plumb the block vent directly to the valve cover pipe and call it a day? Or leave the block pipe venting to open air and run a small filter on the valve cover pipe (which I did on my l16)?  
 

what say ye??

You do not want to connect the 2 directly together.....

I'm sure datsunmike can say why...

Best bet is to just add the small filter...

[mainer311]

DON’T route a hose from the cover to the block. 
 

In my experience, and I’m sure Mike will tell you the same thing, there needs to be some vacuum on the block pipe to help evacuate the vapors in the block. There aren’t many ways to do this. Supposedly there is a way you can actually use the exhaust to create suction through a special fitting, so that’s one option.

 

The vent on the valve cover can be routed to atmosphere via a rubber hose or whatever. 

[d.p]

I read somewhere that @banzai510(hainz)vented the block pipe to open air and it ran fine.  I also read about venting the block pipe to the exhaust past the muffler but no interest in trying to make that work right now.  I guess I will just vent it open and run a small filter on the valve cover.  

[datzenmike]

Sure it will run just like a 1950s and older engine that would run 100,000 between re-builds. Partly this was because of the oil contained acidic combustion by products and condensed water vapor that wasn't removed by the block vent. The old block vent used to be piped down beside the block under the oil pan and used vehicle speed to form a small vacuum. They were called draft tubes and sprayed oil all over the highways. The valve cover also vented into the engine compartment and the smell of unburnt gas and hot oil wasn't that bad. It did a very poor job and oil change intervals were 2-3 k if you were wise. My dad's'51 Chev had a 1" thick layer of white paste in the bottom of the oil pan when it was taken apart for mew main bearings. We always wondered why it wouldn't take the recommended amount of oil when changed.

 

Below, draft tube oil in the center of all lanes. Look at today's roads.

 

You might get the exhaust to suction fumes out but a one way valve would be handy to prevent pressure reversing or a backfire setting off the fumes. I saw an old 60s car flood in a parking lot and somehow it backfired and blew the valve cover and oil pan half off.

 

You see, even with oil changes that are 1/3 today's intervals the engines simply did not run clean enough and this shortened their life. True oil is better today and they even have oil pumps and filters now.

 

 

I'm in the same boat with a home made intake for R-1 carbs. I'm running with them open to the engine compartment. It's a good engine with little if any blow-by and I forget it's like this. I drive a couple of K a year (all at once in the summer) and change every 2 years. It's barely darker than new when I do change it. I would prefer some kind of Positive Crankcase Ventilation and will work towards this. 

 

 

[d.p]

Anyone mounted an autometer tach to their steering column before? 

 

I have at trick mount that @mainer311 gave me that works with my sunpro tach but doesn't with the autometer.  The autometer doesn't have that screw in plug on the back but it came with a mount that you can screw into the column but wondering if anyone knows a different way? 

[d.p]

Can someone tell me if my alt and starter are wired correctly? I ask because when I hook up the negative cable to the battery (pos already connected) the alternator clicks. 

[d.p]

Starter:

 

 

[mainer311]

That looks correct to me. Does it click once, or keeps clicking?

 

Also, I see you're still using the original yellow colored wire for power. If this is a higher amp alternator, you might want to strip that out of the harness and use something beefier with a fusible link in it.

[d.p]

Just clicked a couple times but once o tightened the negative terminal down it stopped so I think I’m good?  It’s a 60AMP for a 200SX.  

[mainer311]

It was probably clicking because of intermittent contact. Might want to upgrade your wire size though. You've almost doubled the current capacity, and the wire stayed the same. Give it a nice big ground wire too. Same gauge as the positive.

Edited February 26, 2021 by mainer311

[d.p]

Where does the power wire go to from the alt? Starter and get power via the starter to the battery? 

[mainer311]

Alternator power gets tied to the battery via the post on the starter solenoid.

 

That yellow wire is in the wire harness that runs just below the battery tray. If you unwrap the harness a little bit, you can pull just that yellow wire out. It goes directly from the alt to the post on the starter.

 

Edited February 26, 2021 by mainer311

[datzenmike]

1 hour ago, d.p said:

  It’s a 60AMP for a 200SX.  

 

What year? The '77 was external regulator like the 521. The '78-'79 were internal. I don't think the alternator should click at all or the volt regulator if that's what you have.

[mainer311]

10 minutes ago, datzenmike said:

 

What year? The '77 was external regulator like the 521. The '78-'79 were internal. I don't think the alternator should click at all or the volt regulator if that's what you have.

 

His is a later one, you can tell by the case.

[d.p]

11 minutes ago, mainer311 said:

 

His is a later one, you can tell by the case.

Yeah it’s from 80 200SX IIRC and I took the VR off and jumped the wires.  

[d.p]

Can someone tell me what is what with these alternator mounts?  I was using the far right one but the adjustment faces the firewall.  The middle one came off my l16 and the left one came off this L20b. 
 

mainly interested in where the one from the right came from cause I got no idea.  
 

 

[d.p]

2 hours ago, mainer311 said:

Alternator power gets tied to the battery via the post on the starter solenoid.

 

That yellow wire is in the wire harness that runs just below the battery tray. If you unwrap the harness a little bit, you can pull just that yellow wire out. It goes directly from the alt to the post on the starter.

 

min that pic the big red wire on the back of your alt goes where? To the starter or to the battery?

[mainer311]

22 minutes ago, d.p said:

min that pic the big red wire on the back of your alt goes where? To the starter or to the battery?

The post on the starter. The battery also has a big red wire that goes to the same post.