My 620 build thread.

[J's 620]

Here’s this beauty of an alternator. I rebuilt it using a kit I bought online, alternator parts.com/ national quick start. Should have 105 amps now. 
 I took it to an alternator shop to get the bearings out and the guy confirmed for me it’s a Delco/Remy cs130. It comes from an 88’-91’ eagle premier I think. Definitely that year of eagle. 

[frankendat]

Way to go Idaho,looks fantastic.I didn't know that alternators could be rebuilt with a DIY kit. Great information!.

[J's 620]

I started it up last night, no muffler on because the exhaust manifold I put on is a tad longer than my stock. It sounds WICKED loud!!! I wanted to drive it to work today but idk if I can put myself through that! Besides I figured it would be best to let it get it’s first heat cycle so I can re torque the head and check some other odds n ends. I had a water pump leak when I filled it with coolant so I tightened those bolts down a bit over spec to stop the leak. I just do dry gaskets. The timing cover also seemed to need a bit more than spec. Another snag was the manifold gasket protruding into where the thermostat housing seats, took a chisel to that and carefully removed some excess. All is well and I can’t wait to get it to a muffler shop on Friday. I may post a video but you’ve all heard an L20B, nothing special here. 

[J's 620]

So for now I’ll run it as is but I want that Schneider cam Hainz is running and has suggested. I think it was about $200. Can I just swap that in without doing anything to the rocker arms? When I was going to get a delta grind, they told me to send them my rocker arms to “recondition” them. Would this be the case with a new cam?

 

I found the answers I needed. If the rockers look good, no grooves n such then you can swap cams. However no cam manufacturer has an off the shelf cam available, it’s regrind only. I should have known that. I don’t want any down time on this truck right now so if I find myself parking it for the winter I’ll have my cam sent in. Schneider is a cheaper option over isky. It’s a $100 difference. 

Anywho, Ratsoon on! 

Edited September 17, 2020 by J's 620

[J's 620]

I need to route my coolant bypass lines a little better, I didn’t have enough hose to get a clean setup. The line from the manifold is “tee’d” in with the thermostat bypass line. 

[banzai510(hainz)]

J what is that blue hose? is that the fuel lines???????????

 

well you got it running which is great. Hope you primed the oil pump before start up.

 

If it runs good don't worry about the cam. You might get more HP improvement by just a bolt on 38/38 weber and live on a flat area, L20b be better w the 38/38.  EZ is build up a head on the side while your truck is running so one don't rush thru and make a mistake.  Just my thoughts

 

 

as for the wrap on the exhaust some say it keeps the heat in and can cause a manifold to crack and rust out faster . other like them.

[banzai510(hainz)]

I like the stock airfilter   plus its quieter  and don't have to fuck cleaning the airfilter

 

just make sure those inner hex allen are tight or have removable lock tite on there. I had one of my bolt go down the carb. Lucky I caught it. It was jammed up then I open the air filter and cycled the linkage went past the butter fly and had to fish it out

[datzenmike]

Find the temp sensor from inside the old air filter and get the ATC working. You'll never have carb icing again.

[J's 620]

Those blue lines are vacuum lines. It’s silicone hose. Yea I did prime that oil pump, I think it’s a ka24de pump, I’d have to post up the part #. The box says it’s a Japan part and I don’t remember where I bought it from. And I do have the Weber 38 on there. I hate that stupid filter they give you. I can see you would have to clean that like twice a month. 
 Hopefully I didn’t toss the cut out pieces and temp sensor from my air cleaner!! I was hoping that the coolant running through the intake could help with carb icing. 
 Right now it’s at a friends house and we’re almost done fitting up the exhaust. It was a loud ride this morning. 
 I drilled 2 1/8” holes in the thermostat,(it’s an aisin brand) and I noticed the temp was a bit cold while driving, but when idling in the garage it climbed to operating temp. I hope I don’t need to do a thermostat now and do only one air bleeder hole.

Edited September 18, 2020 by J's 620

[J's 620]

The manifold was cleaned down to bare metal then  painted with some vht flame proof then I wrapped it. I hope the paint keeps it from rusting, but I wouldn’t want to source another manifold if it cracked from the wrap. That would really suck. I’ll have to keep an eye on that. 
 

I did lock tite the Allen screws on the carb adapter plates.

[J's 620]

I had some major oil leaks, I had to sinch down the oil pump a little bit more, and oil was coming from one of the alternator mount bolts, the one in between the lower mounting feet of the alternator itself, that threads into the block.  
 

 I beleive I added a little too much oil and this could be a contributing factor. Once the truck is off the jack stands and on level ground I will check the oil level. 

Edited September 19, 2020 by J's 620

[J's 620]

Let’s get technical. Ever since I did an alternator swap my charge light glows. Never had battery issues, and the alternator has always showed it’s charging. However sometimes at higher speeds the light will go bright briefly and go off. This was before I rebuilt it. Today while driving and approaching higher revs but probably not real high, the light was bright more frequently and on for longer periods. The charge light still glows as well but the alternator is still charging the battery. I did rebuild this thing but I didn’t replace the regulator. Culprit? I don’t know. 
 To convert to an internally regulated alternator I followed someone else’s guide on this forum. Maybe I have a ground issue? Any ideas, should I start a new thread?

 

i used the search feature and did some research on other sites, it seems that I need to make sure my grounds are really good and I need to trace some high resistance in the charge light circuit. Troubleshooting should narrow this issue down. If and when I find it I’ll explain what was going on. 

 

got my meter out....... 14.2 at idle and lower rpm, as I rev up it starts to fluctuate from 13.6-14.2 then as the charge light starts to blink on and off the voltage drops to 12.2. So that should give me something to research for. all grounds are good, I'm getting the same idle voltage, and I suspect I would get the same voltage reading at my grounds when it starts to fluctuate or drop. 

Edited September 20, 2020 by J's 620

[J's 620]

I found my problem. One of the bricks in the brush assembly broke off from the copper lead wire. I was driving to work on Monday and the charge light came on, this must have happened that morning. Also, the front bearing is completely loose because the alternator shop guy broke some chunks out of the front housing piece where the bearing seats when he hammered it out. The entire bearing assembly spins in the housing. That’s probably not good. I called the guy and told him, he said he could peen it to the housing but the bearing may never come out, but he did have a brush assembly in stock. I chose not to go back, I just bought a “new” alternator from rock auto. 1989 eagle premier. 

im tired of dicking around with these hack job Idaho mechanics, exhaust shops, machine shops, and generally everybody. No offense to my Idahoans. 

Edited September 25, 2020 by J's 620

[J's 620]

Right now I’m in the process of hooking up an auto meter gauge trio: temp, oil pressure, and voltmeter. I’ll take pics and tell you how I go about it. I can tell you getting the temp sensor probe and sealing nut through the firewall was a bitch. I plan to mount it on top of my center console, so the 6ft of probe wire is not long enough! I do have a plan.....

 

oh! I did not have oil leaking from alternator mounts, it must have been seeping from the head gasket, I retourqed, but obviously need to do it again or go thicker oil. I’m running Mobil1 0-40, Probably way to thin but it’s good oil, so 5-40 is probably what I will try. My bell housing plate is leaking a bit as well and I know my rear main is only a few years old now. I’ll probably switch to thicker oil and accept the oil leaks. Whatever it is what it is. 

Edited September 25, 2020 by J's 620

[J's 620]

It’s been awhile right? 
 I’ve been driving the shit out of my 620. The new alternator I bought from rock auto did the very same thing on another Monday morning. The charge light lit up, when I pulled it apart the brick was separated from its copper lead wire. I rebuilt both of my alternators, I had the local alternator shop guy peen the loose front bearing in my pretty blue alt. and it is currently running just fine but I’m seeing a rusty colored dust on the fan and pulley. I’d say something is metal on metal, it’s also giving a squeal when I shut the engine down. 

[J's 620]

I’ll get some pics and a super short how to on my gauge trio, but those are doing great. I haven’t plumbed in the oil pressure gauge. The temp gauge confirms my low temp at high speeds, I think the 2 air bleed holes in the stat could be one too many or it might be that it’s been cold as shit here in east ID. No carb icing, the choke works well on the Weber and I’m pretty much dialed in on the tuning. My idle is a bit high but I think the A/F is ok. I do believe in Hainz’s theory of the uphill bog down, when goin up a hill more throttle creates a vacuum loss, this equals loss of acceleration. It’s real, and I guess I’ve never noticed it, not until I’ve had my head worked on and cleaned up. But dang, around town and on flat ground this little 4-banger gets down. 

[J's 620]

Anyway, a lot of people envy anything Datsun, it’s a piece of history and brings back memories. People love them and wish they still had them. Trust me, I hear it daily at least. I’m not sure what my next thing to do is on this, as I’m still technically tuning the carb for weather changes. Let me know what you guys think about that rust colored dust on that alternator pulley. 
 I’ll update on Sunday with some pics, belt info, and other things I might have missed. Oh speaking of that, I ditched the silicone cam cover gasket and made one from 1/8” cork/rubber gasket from Napa. The sili kept slipping out and It would piss out oil! 

[J's 620]

Look what I picked up today! A 78 620, really good condition.

 Here’s a side by side of the 5spd that came with the truck(the tail gate even says 5spd!?) and next to it is a mystery 5spd. It’s about 5 to 5-1/2 output shaft turns per 20 input shaft turns. 80 truck or 810? Has 71b on it but it is not an Lseries bell housing. Notice that front cover says t5, I doubt it’s a borg Warner, those look way different right?

Edited December 5, 2020 by J's 620

[datzenmike]

 

The one on the right by itself is for a Z series engine. Says ZL71B and it's an FS5W71B 5 speed made in '80 or newer. Twenty input turns in first gear....

 

5.5 output turns..... wide ratio transmission used in the '82-'83 S110 200sx car and only on 4x4s in the 720. Check for the absence of the speedometer drive in the tail stock making it it a 4x4..

[J's 620]

Well here’s what I worked on today.

This is the 5spd with the z series bell housing. This set of yellow wires, is that the speedo drive or something else? I didn’t get under my truck today to look for what that looks like so I guess I’m ignorant to what I’m looking for.

Edited December 7, 2020 by J's 620

[J's 620]

I now believe I have 3 5spd transmissions.....

 The trans on the tailgate seems to roll through 6 gears and has the same ratio as that z series bell housing transmission . I think the casting says L4

 the 5spd hook to the L20b I’m assuming is a 5, it says L8 but I haven’t tried to shift through it yet.

Edited December 7, 2020 by J's 620

[J's 620]

Here’s a bit of my gauge trio set up.

 •First up, where I mounted it.
 •how I plumbed in the temp gauge. 

The adapters that came with it went right in. 1/2” npt  

 •then you have voltage at idle, voltage at idle with lights and fan blowing. 
 • this is where I grabbed the lighting circuit from, which is the pigtail for my factory clock which isn’t in. I took some 18awg wire, covered it in solder to make it stiff, soldered that to some 14awg wire and stuffed it in to the terminal of the pigtail connector. 
 The rest was per instruction from autometer. The oil pressure isn’t plumbed in yet. Yes, I butchered the diffuser vanes of the vent. I used to have some micro ductwork coming off that. It was S.S. and real cute.

Edited December 7, 2020 by J's 620

[J's 620]

I’ve been hearing some annoying noise this past week...... I narrowed it down to the alternator. I noticed some red dust on the pulley and fan. Well.....

[J's 620]

I don’t know why but the fan was digging in to the front cover. Either my pulley was warped(and it looks like it is!)or I just didn’t have the shaft nut tight enough or whatever, idk? I ended up putting a new brush kit I had in my other alternator that I bought new, I posted what went wrong with that, and I put that in the truck. It charges with better voltage than the pretty blue one. 

[J's 620]

Look at how the back of the fan and around the shaft is all scarred up. I added a small washer in this space to keep that from happening again. Hopefully.