New at engine rebuild L16

[Richie]

On 8/7/2021 at 12:07 PM, datzenmike said:

 

 

1/  2 liters GL-4 it's critical that it be copper/brass 'yellow metal' compatible, GL-5 is NOT! 90w you can try a synthetic but I find on old Datsun transmissions, and all Datsun transmissions are old, it tends to form leaks. A new output seal usually fixes this. Not always. Never over fill. When you can't get more in the fill hole.... it's full. Excess oil will just get foamy and go out the plastic breather, and bubbles do not lubricate

 

2/ Anything BUT a synthetic is fine as you want some wear, as long as you change it within a thousand miles or so. Drive it at varying speeds and loads, don't drone on at a steady speed. Change to an oil high in zinc anti scuff ZDDP such as a diesel oil (there are other brands) Don't run conventional gasoline engine oils as the ZDDP levels are half what they used to be. I suggest Shell Rotella T4 10w30 or 15w40. Always change the filter too. Fill till the dip stick reads full about 4.5 liters. Half fill the oil filter before spinning on and wet the rubber gasket. Check after running, top up as needed. If a total rebuild with new gaskets and seals you can switch to a synthetic after break in if you want, but waste of money unless running some kind of power adder.

 

3/ Fill the rad till full but leave 3/4" for expansion*. An L18 with heater is just about 1.5 US gallons if calculating the amount of anti freeze to add. Once thermostat opens any air that might have been caught will escape into the top tank of the rad. It's absolutely impossible for air to be trapped in the engine. Check and top up as needed.

 

* Over filling will just cause the rad to expel any excess coolant. Get a coolant recovery container and special rad cap and every time the engine cools any saved coolant will siphon back into the rad.

 

4/  The 620 was built for use with DOT 3 but DOT 4 is totally compatible and a nice upgrade. Other than DOT 5 (NO NOT USE!) brake fluid absorbs water which has a lower boiling point so it should be replaced every 30k or 24 months. 

 

 

Hey Mike, what fuel should i run now that i am about to do the first start and setting everything? I know the compression ratio is higher now. 

Also i am a little confused on the engine oil. Youre saying throw some conventional oil 10w30 in, with the lucas zinc additive first, then throw in some good oil with high zinc? 

I am trying to buy everything on amazon now so i can have it for friday. 

 

Also just a head ups if you have any comments on this, i am getting this alternator 

https://www.oreillyauto.com/detail/c/ultima/charging---starting/alternator/f7cab2ae3cc0/ultima-60-amp-alternator-remanufactured/oat0/r111307b

 

I changed the wiring harness to a 12 circuit aftermarket harness. Thank you. 

[datzenmike]

Quick recap of what was done for the rebuild???

 

 

You could just run Rotella T4 10w30 right from the start. 

 

Put the year of your 620 in your profile. The 50/60 amp alternators are for cars and later 720 trucks and are larger diameter than the stock 38 amp one in the 620. It's not a good fit. Did it say it fit the 620???? You can try it, but I found there isn't much room for it against the block and when swung away to tension the belt, it hits the grease fitting on the idler arm and cuts into the rad hose.

 

 

 

 

 

 

[Richie]

33 minutes ago, datzenmike said:

Quick recap of what was done for the rebuild???

 

 

You could just run Rotella T4 10w30 right from the start. 

 

Put the year of your 620 in your profile. The 50/60 amp alternators are for cars and later 720 trucks and are larger diameter than the stock 38 amp one in the 620. It's not a good fit. Did it say it fit the 620???? You can try it, but I found there isn't much room for it against the block and when swung away to tension the belt, it hits the grease fitting on the idler arm and cuts into the rad hose.

 

 

 

 

 

 

1974 Datsun 620 L18
I got the cylinders bored to 86mm 

I got the head rebuilt and they shaved off a little to clean it up. The block did not get shaved. 
New bearings, new pistons, oil plugs and freeze plugs. 
 

basically with the alternator, I need a self regulated one that fits fine. 

[datzenmike]

8.43 stock and 8.58 with 86mm pistons. Regular gas, your choice.

[Richie]

25 minutes ago, datzenmike said:

8.43 stock and 8.58 with 86mm pistons. Regular gas, your choice.

E85 it is! I am joking. thank you

 

[datzenmike]

I doubt it will make a difference. You can adjust the timing.

[Richie]

so do not get that alternator, the one I placed with the link?

 

[datzenmike]

15 hours ago, datzenmike said:

The 50/60 amp alternators are for cars and later 720 trucks and are larger diameter than the stock 38 amp one in the 620. It's not a good fit. Did it say it fit the 620???? You can try it, but I found there isn't much room for it against the block and when swung away to tension the belt, it hits the grease fitting on the idler arm and cuts into the rad hose.

 

This is my experience with a larger diameter car or later 720 alternator. It fit, but rubbed hole in the rad hose and bumped against the idler arm. I switched to a 280z lower rad hose inlet pipe to the water pump to move the rad hose away, used a 720 alternator to block mount to raise the position of the alternator and I may have used a shorter belt. To fit, I had to put the belt on the alternator pulley first then put the mounting bolts in. I may have modified the adjusting strap also I forget. Another problem is that the closer the alternator is to the block the less belt is actually in the groove. I got it to work but wasn't happy with it. Try it, it may work for you, it was a poor fit for me.

[Richie]

4 hours ago, datzenmike said:

 

This is my experience with a larger diameter car or later 720 alternator. It fit, but rubbed hole in the rad hose and bumped against the idler arm. I switched to a 280z lower rad hose inlet pipe to the water pump to move the rad hose away, used a 720 alternator to block mount to raise the position of the alternator and I may have used a shorter belt. To fit, I had to put the belt on the alternator pulley first then put the mounting bolts in. I may have modified the adjusting strap also I forget. Another problem is that the closer the alternator is to the block the less belt is actually in the groove. I got it to work but wasn't happy with it. Try it, it may work for you, it was a poor fit for me.

do you have any suggestions on a alternator that would work? I mean i could figure out the hose situation like you, but chances are it wont be as good

 

[datzenmike]

I think the stock US LR135 alternator for the 620 was (about) 35 amps. If you had the 'cooler option,' I don't know if this was air con or just a heavy duty cooling system, you got an optional 38 amp alternator. Canada were all 38 amp alternators.

 

You could try taking it to an automotive electrical shop that can rebuild it with an increase in output.

[Richie]

3 minutes ago, datzenmike said:

I think the stock US LR135 alternator for the 620 was (about) 35 amps. If you had the 'cooler option,' I don't know if this was air con or just a heavy duty cooling system, you got an optional 38 amp alternator. Canada were all 38 amp alternators.

 

You could try taking it to an automotive electrical shop that can rebuild it with an increase in output.

so i am going to try the alternator i put in the chat first, and get a shorter belt like you mentioned first. I believe i can make it. thank you. Ill update with some pictures. this weekend is going to be all about wires and fluids.

[banzai510(hainz)]

the last number on the belt is usually 5 mm increments then you can figure wheich belt is needed

[Richie]

Alright tomorrow is work on getting everything connected and fluids. Hopefully saturday i can charge the battery and see if the engine will turn. Ill post some pictures of what i am doing. I got an alternator gonna try and get it fit nicely and wired up correctly.

[Richie]

https://imgur.com/a/7m4s68v 
 

this is where I am at with the alternator. Any ideas? I had to get a longer belt. 15360

[banzai510(hainz)]

like I said add a 5 to the part number  15365 if they make them.   I havent gone past 60 myself.  but I put the smaller alt back in as ezer t get in out(more room)

 

 

look like you might need a spacer between the alt tab and the adjustment bracket. thats a big gap.  you want it even so not the dtress the front cover. otherwise its going to get loose all the time

Edited August 13, 2021 by banzai510(hainz)

[Richie]

15 minutes ago, banzai510(hainz) said:

like I said add a 5 to the part number  15365 if they make them.   I havent gone past 60 myself.  but I put the smaller alt back in as ezer t get in out(more room)

 

 

look like you might need a spacer between the alt tab and the adjustment bracket. thats a big gap.  you want it even so not the dtress the front cover. otherwise its going to get loose all the time

I added a 5 like you said. The original one is 15355 this one is 15360

 

also is it back the the hose inlet is almost touching the alt? Like is the heat going to ruin it? 
 

And any ideas for a new alternator tensioner bracket? 

[banzai510(hainz)]

maybe a 5mm longer one.

Its hard to gauge like I said I went back to the stock size as when the belt were it would hit the frame of grease fitting on the joint.  I said fuck it,  35 amper is ok just weak at idle,

 

went went with a turnbuckle sytem on mine , but youll get more movent with the slotted bracket, but to me they alwasy seem to get loose.

Edited August 13, 2021 by banzai510(hainz)

[Richie]

https://imgur.com/a/NhxDJhC
 

well for now at least I turned the bracket upside down and it fits fine. I’m just worried about the alternator being so close the the hose inlet. 

[Crashtd420]

8 minutes ago, Richie said:

https://imgur.com/a/NhxDJhC
 

well for now at least I turned the bracket upside down and it fits fine. I’m just worried about the alternator being so close the the hose inlet. 

Ya I dont get that... I just went out and checked my truck and I could fit my hand between water neck and the alternator and I'm fairly tight against the block.... 

[Richie]

33 minutes ago, Crashtd420 said:

Ya I dont get that... I just went out and checked my truck and I could fit my hand between water neck and the alternator and I'm fairly tight against the block.... 

Do we have the same alternator? And bracket?

[Crashtd420]

2 hours ago, Richie said:

Do we have the same alternator? And bracket?

I had the same altenator and the one I'm using even has a slightly bigger case....

The water neck looks the same, the upper bracket is slightly different but that wouldnt affect the clearance to the water neck...

 

Maybe the lower mount? 

 

[Richie]

14 minutes ago, Crashtd420 said:

I had the same altenator and the one I'm using even has a slightly bigger case....

The water neck looks the same, the upper bracket is slightly different but that wouldnt affect the clearance to the water neck...

 

Maybe the lower mount? 

 

i am using the original lower mount. This is weird but thank you Orielly for returning it 

 

[datzenmike]

 

 

 

 

I think one of my mods was the alternator mount from a Z series engine. It moved the alternator up away from the water inlet and rad hose.

[Crashtd420]

This is my motor 15 years ago before any rebuilding ....

It crusty but it's the only picture I could find of the bracket I'm using

[Richie]

4 minutes ago, Crashtd420 said:

This is my motor 15 years ago before any rebuilding ....

It crusty but it's the only picture I could find of the bracket I'm using

yea my mount is different. its the first mount in Mikes photos. 

 

https://www.oreillyauto.com/detail/c/ultima/charging---starting/alternator/f7cab2ae3cc0/ultima-70-amp-alternator-remanufactured/ost0/r111397a/v/a/6644/automotive-car-1985-nissan-300zx?q=alternator&pos=0

 

Someone told me this work fine too. It is the 300zx alternator. He said it is smaller. What do you guys think?