1978 Datsun 620 - "Sendy"

[Stoffregen Motorsports]

May as well check the valve adjustment while you're in there.

[bxadook]

Hey everyone,

 

So I replaced my valve cover gasket and that has appeared to fix the leak.

 

Today, I learned that a garage opened up in my apartment complex which has suddenly opened a big juicy can of worms for me. 

 

In the next month I want to replace the brakes and do a suspension overhaul. The overall goal is to make the truck safer and to prepare it for an eventual motor swap. My L20b is still running strong. 

 

Planning on doing the D21 disc brake conversion, and converting the rear brakes to disc later as well. 

 

Front suspension parts list: 

Front upper and lower bushings 

Strut bushings

Sway bar bushings

Ball joints

Struts

Sway bar link

Tie rods 

 

Brake conversion parts list:

D21 2wd  truck hubs and dust shields 

D21 or pathfinder 4x4 calipers with mounting brackets

D21 rotors 

Bell-tech D21 drop spindles

 

Are there any issues with this list or glaring things that I am missing? Any recommendations? 

 

I am not planning on doing anything big, like a coilover suspension or Willwood brakes just yet because there is a high likelihood I will break or fuck up something as I am learning. My apologies if it seems as if I do not know what I am doing, because it is true. Any advice would be helpful. 

 

Ben

[Bucketerium]

I just finished up my D21 front conversion. I had to swap out my wheel studs as they were ridiculously short. For even the steelies, they were too short, let alone the aluminum wheels I installed. Something you'll probably want to consider.

[bxadook]

How long were your studs and what size did you change them to? 
 

ben

[Bucketerium]

I installed some Moser Engineering 8255 studs. Everything looks good & seems to fit about right so far. Haven't driven the truck with them in yet, but I see no reason to be concerned yet. This particular model is long as shit & I cut about 3/8" off my front studs. They had a model with all the same critical dimensions, but I opted for the longer ones. They're also M12x1.5 threads, not the 620 stock M12x1.25.

 

I'll measure my stock D21 ones when I get home.

[bxadook]

So I am in the process of upgrading the front suspension and I received two balljoints from Rockauto, the MOOG 9045 balljoints. They are both different. One clearly isn't made for this truck and has made me skeptical that the other will fit. The one that I thought would fit sits in the lower control arm like so. I haven't torqued it down fully but really not liking how this is sitting in the control arm. 

 

 

 

Is this a normal gap? 

 

 

The above diagram seems to indicate that is gap is normal but would like an opinion on this. 

 

Edited post for photos.

If that didn't work: 

https://photos.google.com/search/_tra_/photo/AF1QipMz5ZRba11CQS3C9eTN4mNmuE9BlJKZqqF2OJSF

https://photos.google.com/search/_tra_/photo/AF1QipMJMcbx1Q3aQsVz1LF7MMxGABudUl4yxCXZtsPO

 

Ben

Edited March 29, 2020 by bxadook

[Ooph!]

The pictures aren't showing for me in either Firefox or E

[bxadook]

edited 

[bxadook]

So guys, 

 

I am basically done with the D21 4wd 2 piston caliper disc brake upgrade for the front. Pics will come later. It took me about a month and a half. Was anticipating driving the truck to get an alignment and had issues. 

 

I attempted to drive the truck out of the garage. It starts, but I have to give the truck gas to start it consistently. Had the same problem two months ago, but once everything was warmed up the truck would start no problem. Once started I have to give it gas to keep the truck running. It also  sounds like it is running rough while I am giving it gas, and while putting it in gear. It feels like I have to give it a lot more gas to get the truck to move as well. I was worried it was my new hub bearings, but the wheels still spin freely. Needless to say, I got the truck 10 yards out of the garage and got freaked out. 

 

I suspect I have a vacuum leak or a fuel issue related to the work I did, as well as letting the truck sit for a little while and letting everything dry up. 😞

 

Please gods help me!

 

Ben 

[bxadook]

Oh boy so I learned a lot about my truck since the last post but here is my progress! 

 

I'm lovin' the lil rake and stance it has.

 

 

Yes I will tidy up the coolant line and get that fuel line choked up on the fitting 🙂 

 

 

D21 Drop spindles with D21 hubs

D21 4WD 2 piston caliper conversion in the front.

Power stop calipers for 4WD D21, and Brembo vented rotors for a 4WD D21.

The existing hard brake lines running from the caliper will NOT work with this conversion and you need to run a banjo bolt with crush washers with the proper brake hose for the caliper.

KYB Gas-a-just shock absorbers.

New ball joints, tie rods, and center link.

Wheel Vintique Rallye's 15x8 running a 215/65/r15 in the front and 15x10 with a 255/60/r15 in the rear. Need to run a hubcentric 100mm to 108mm adapter to make this work.

 

Wanted to run a smaller stretched tire in the rear, but my tire shop wouldn't let me. Will look to run something other than this big ass tire in the future, but for now it will do.

Got it off the stand - and it wouldn't idle so I replaced the stock Hitachi with a Weber 32/36 DGEV - and yes I will plug in that electric choke. I was having issues getting it to stay, but in this hot AZ weather it starts just fine without it for now.

Will delete that coolant line running to the manifold eventually as well.

Took pictures of the EGR delete. Yeah it's janky with JB weld, but this is a shit box.

Have a few things to tidy up but just needed to share and update since the last post. 

Thanks for everyone's past and present help. The search function has been absolutely vital in this build!

 

[DavNova]

That looks great mate! 

Appreciate the break down on that, i may have to do something similar.

[datzenmike]

On 6/5/2020 at 10:42 AM, bxadook said:

Yes I will tidy up the coolant line and get that fuel line choked up on the fitting 🙂 

 

 

 

Will delete that coolant line running to the manifold eventually as well.

 

 

 

That coolant line needs to be there and connected to the intake. Besides the obvious two possible leaks the way it is, the coolant actually helps cool the intake that soaks up radiant heat from the close by exhaust. Really good in hot weather to prevent vapor lock and hard restarts.

 

The weber air filter also has a provision on the front driver''s underside for fitting for that valve cover hose.

 

Has much earlier elephant oil cap, (nice touch) and that's a '79 thermostat cover.

 

Is that the return spring for the carburetor on the valve cover bolt. It really should be in line with the throttle cable or it will accelerate the wear on the throttle shaft pulling sideways.

 

Like, I mean I really like, the earlier grill. It's so much better than the '78.

[banzai510(hainz)]

Matter of fact my return spring is a similar set up

 

i would get new rad hoses to clean it up and maybe shorten up the fuel line or make it look better or prebent metal line.

Edited June 8, 2020 by banzai510(hainz)

[Stoffregen Motorsports]

Get a gallon of Purple Power and a handheld pump sprayer. Coat the whole engine bay and let sit for a couple minutes then pressure wash off. Most things (including the radiator hoses) will look like new again.

[bxadook]

Thanks for the help guys! 

 

i reconnected the coolant line and tried to clean up the engine bay. Pics to come soon. 
 

I just sourced an l20b with a 5-speed from a Datsun 720 for $350. Going to take a look at it tomorrow. Would be fun to swap the trans out and maybe rebuild the motor.

 

I currently don’t know the year of the source truck but presumably because it’s an l20b the tranny should just swap over no issues??

 

related question: what’s the best source for performance oriented parts for an l20b?

 

money will soon be a non-issue for me. No girlfriend. Just the truck and I soon to be in Colorado. Taking a nice hospital job. 

 

Edited June 9, 2020 by bxadook

[banzai510(hainz)]

I’m not into your tire wheel set up I like my stuff tucked in and lowered.

as for the motor the L20 is a great up grade but need to see if the head is a round port exhaust but I think you can use the square port exhaust manifold.

be honest I would just clean the engine compartment up and just drive it and build this L20 block on the side and when your ready swap it over.L20 and other L motor the power is in the head and carbs.L20 is a long stroke and a big upgrade even from a L18. Bit all other improvements are pretty much the same in cost.howeber the L20 is 6 bolt crank While the L16/18 is 5 bolt

[bxadook]

I’m already aware my rear tire is too large. Probably going to downsize to 15x9 in the future. 
 

This is already an L20b and right now I’d just be swapping the 5-speed into this truck. 
 

my current exhaust manifold is a round-port which doesn’t fit any of the aftermarket headers on the market today. 
 

Would love to rebuild the new motor from the ground up and eventually swap it in. Was reading that DCOE setups just guzzle gas and don’t net power without port matching the intake and exhaust. Would love to upgrade internals but just don’t know where to find them. 

Edited June 9, 2020 by bxadook

[banzai510(hainz)]

I would not worry about the headers .

datzenmike says one can pull out the exhaust liners if you have a round port.

too me a Cam and dual carbs are the things to get if available . And a electronic ignition.If you don’t have this already

internally most is stock Just the camshaft and valve train and carbs.

 

fimd a Weber 38/38 and bolt it on since you have a L20 already

L20s are 1.375 intakes and to match port is based on the newer manifold but one can open up the stock manifold pretty ez

Edited June 9, 2020 by banzai510(hainz)

[Stoffregen Motorsports]

11 hours ago, bxadook said:

 

Would love to rebuild the new motor from the ground up and eventually swap it in. Was reading that DCOE setups just guzzle gas and don’t net power without port matching the intake and exhaust. Would love to upgrade internals but just don’t know where to find them. 

As strange as it may sound. the L20B does not have a lot of performance parts available for it. At least nothing really bolt on. Sure, you can do a header and intake, but that's about it for bolt on stuff. You won't start to see any real gains in HP until you remove the head and install a good cam, valvesprings, have a good 3 angle valve job done, and then possibly some porting. In the bottom end, raising the compression is a must. Re-curve your distributor and then build a nice 2.25" exhaust system to get some easy horsepower.

 

Really though, unless you can do this work, you're going to pay someone to do it, about what it costs to swap in a KA24E or even DE. Motor swaps are easy HP and can be done in your garage, if you can weld.

 

So what do most Ratsun owners do then? They install a DGV Weber, a mild cam and have a valve job done, re-curve the distributor and build an exhaust system. These mods are good for about 15hp, more if properly tuned.

[]2eDeYe]

An L20B 720 is going to be a 1980. One year only, the next year had a Z series motor. 

 

Love the look you got going on B)

[bxadook]

Got my 5 speed! 

 

 

 

 

 

 

 

Fuel pump looks new!

Got a chance to ride around in the truck it came from and it felt like it had more power than my current L20b. It wouldn't idle, which is the same problem that my truck had. He said he replaced the fuel pump, so that leaves the carbeurator as the issue.  It has an ATK reman sticker. I do not know the mileage. It did come from a 1980 720. The bolt was to the left of the center of the tranny, so I knew it would work for my truck! Gonna be fun to tear this lil guy down. Sorry Mike, I did not put the fram on it!!!

 

I am not dead set on doing a KA swap currently as I am having a ton of fun already. Maybe when my truck feels old... lol. With the new carb and this little side project I think a KA swap is off the table for now. I can daily my truck. The truck is so much fun to drive. 

Edited June 10, 2020 by bxadook

[Stoffregen Motorsports]

I was just using the KA swap to illustrate the point that swapping in a newer motor would require about the same effort as building up the L20B.

[bxadook]

To be determined what I will end up doing. I appreciate the point you were trying to make. For sure it would be easier to just swap in the KA if I wanted just power. 

 

I also want to learn, and the L20b seems like an easy/relatively cheap to platform to learn how to do this type of work. The end goal here is continued learning more so than actual power gains.  Will likely end up getting a different platform/car when this goal changes. 

 

For all I know, the motor will end up sitting, when I impulsively buy a KA. (I impulse bought this 5-speed + L20b)

 

[banzai510(hainz)]

just put a 38/38 weber on there and Im sure youll like it  cheap and your DONE!!!!!

[bxadook]

I am sorry hainz but curiosity got the best of me, and I think I ended up making the right choice. In the donor motor I found: 

 

 

https://photos.app.goo.gl/bhWbyR5PhYoJGQKR7

 

Video of sludge coming from water pump. I sent this to my brother via text if you are wondering about the speech. 

 

 

 

Pitting in the water pump? Sorry I cleaned up the sludge when I took this photo.

 

 

Latte coolant / oil coming up through the valves? 

 

 

It had a square port manifold gasket, yet where the exhaust flows it is round. Is this normal? My 1978 L20b did not look like this at all! Its almost like a portion of the head was eaten away by acidic exhaust? Every exhaust port looks similar. 

 

https://photos.app.goo.gl/FECdEJJwobVE9Ba68

 

The exhaust ports are all shit. The intakes actually have a portion at the 6 o'clock position(gravity dependent I guess) where it is eaten away. Is the EGR bad? Is it recirculating too much acidic crank case gas? Was it the coolant leak into the oil worsening the pH of the motor?

 

 

 The gasket in question. 

 

 

This is the intake manifold. My 1978 motor was clean - you could see the manifold metal. Here is the 1980 motor coated in a black tar. The coolant ports on the head for the intake manifold also appeared to be clogged. Half of one of the intake ports on the manifold was completely blocked off with crap. 

 

I am pulling the head off tomorrow. Will make sure to set the motor to TDC before I do so.  Super curious as to what I am going to find, I suspect there will be a blown head gasket. This is so cool, learning a lot. 

 

All I wanted is the transmission. I hope it is in good shape. Have new seals coming in this weekend, and clutch coming in next week. If the block ends up being crap I will turn it into a table or something. This head appears to be totally ruined. 

 

 

Edited June 13, 2020 by bxadook