New Truck - '71 521

[mainer311]

1 hour ago, andyZ00m said:

Dang!! SO is this an inherent design flaw in the Weber?

 

The issue is that it highly depends on the engine/application. Things like ignition timing that can drastically change idle RPM when compared to butterfly position, etc. 

 

I used to have a 32/36 DGV on my truck and I was never able to fix it correctly. I got close. It was a good learning tool though, since the operating principle of most Webers is the same. It made loud sucky sounds and looked cool. 

[andyZ00m]

2 hours ago, mainer311 said:

 

The issue is that it highly depends on the engine/application. Things like ignition timing that can drastically change idle RPM when compared to butterfly position, etc. 

 

I used to have a 32/36 DGV on my truck and I was never able to fix it correctly. I got close. It was a good learning tool though, since the operating principle of most Webers is the same. It made loud sucky sounds and looked cool. 

 

Hahah. It def makes loud sucking noises. I ordered a jet kit from pierce and will mess around with different combinations. Gunna start with slightly larger idle jet (60 instead of 55 stock) and see what happens as that's super easy to change.

 

2 hours ago, Crashtd420 said:

For the most part people say you just have to drive the truck like the weber likes because the tune is close enough..

 

Mike (the carb whisperer) said he went to a larger main jet and that helped the last time he did one of these with the same issue so I have stuff to play with. Im cool with driving it like the weber wants as well but I think I still have some room to improve it.

 

The engine is dieseling a bit too so I need to dial in the timing/idle/mix/jet situation.

 

Edited December 19, 2023 by andyZ00m

[Crashtd420]

1 hour ago, andyZ00m said:

 

Hahah. It def makes loud sucking noises. I ordered a jet kit from pierce and will mess around with different combinations. Gunna start with slightly larger idle jet (55 instead of 50 stock) and see what happens as that's super easy to change.

 

 

Mike (the carb whisperer) said he went to a larger main jet and that helped the last time he did one of these with the same issue so I have stuff to play with. Im cool with driving it like the weber wants as well but I think I still have some room to improve it.

 

The engine is dieseling a bit too so I need to dial in the timing/idle/mix/jet situation.

 

 

Definitely try it if you don't mind messing with it.... 

I drove around for a month with a jet kit on the passenger seat in my truck trying different combos... not a downdraft but a single side draft so I had my own unique issues....

[andyZ00m]

22 minutes ago, Crashtd420 said:

 

Definitely try it if you don't mind messing with it.... 

I drove around for a month with a jet kit on the passenger seat in my truck trying different combos... not a downdraft but a single side draft so I had my own unique issues....

 

Ha! I bet you did.

 

Just messed around a bit more with the stock bits in there. Its running very nicely right where I have it but the dieseling is a bit worse.

 

11TDC, mix about 1.2 turns out, idle comfortable, 55 idle jet.

 

Had it at around 8 and it was running nicely but the hesitation is better with the above settings but dieseling was less. 

 

The dieseling is likely related to motor being quite warm by the time I was done testing. Need to flush the radiator and get new coolant in there. Shits gross.

Edited December 19, 2023 by andyZ00m

[datzenmike]

The L20B is 12⁰. 

 

My '73 620 L16 says 5⁰.

My Haynes 510 manual says 10⁰ for the L16

 

So I don't know. Rule of thumb, run it as advanced as you can and it is still happy, damn the emissions.

[mainer311]

If the mix screw is only 1.2 turns out, going up to a 60 will make it worse. I too thought that fattening up the idle would make the flat spot go away, but it made it worse. These little L16’s like either a 50, or the supplied 55. Keep in mind that changing the idle jet will affect the entire transition circuit, as well as low RPM driving around town.

[andyZ00m]

5 hours ago, mainer311 said:

If the mix screw is only 1.2 turns out, going up to a 60 will make it worse. I too thought that fattening up the idle would make the flat spot go away, but it made it worse. These little L16’s like either a 50, or the supplied 55. Keep in mind that changing the idle jet will affect the entire transition circuit, as well as low RPM driving around town.

 

Totally agree. with the idle and timing range I had before, the engine ran best with the mix screw more like 2-2.5 which was where the suggestion for idle jet came from.

 

I got it to a much better spot after today. Gunna drive it a bit more and see whats up. Im realizing the tuning and optimizing of this thing is gunna be a longer process that I thought.

[andyZ00m]

Merry Krampus!

 

Did a radiator flush yesterday of the ancient and disgusting coolant. Was nasty, did two flushes and still was really gross in there. Replaced the hose on the heater core that was leaking and so far the leak is fixed. The fiddly little hose behind the engine is super annoying but if repaired sooner could have avoided a million years of rust on the back on the engine compartment.

 

 

Heres a video of the fluid draining so you can see the color. https://i.imgur.com/UIxo1W1.mp4
 

Next thing is to replace the shocks and sway bar link bushings in the front and well as the torque rod bushings. I found the part number from another thread but they are too big and not the right thing I dont believe, they are poly and wrong shape/size. I also am looking for any advice/pitfalls for replacing this stuff. Do I need to have it aligned after I replace?

 

 

 

[datzenmike]

Check and snug (not over tighten) the clamps while the hoses are warm and soft.

 

I would flush the block as the coolant is shared with it and the heater core. Run a garden hose in both directions through the core with it set in the HOT position.

 

 

 

 

Polly bushings are not compliant enough for use on the tension rods. The bushing should flex during suspension movement. Polly will force the tension rod to flex and this can lead to metal fatigue and breakage. You may want to drill a few holes to allow up and down flexing. Compression will not be affected. Rubber replacements would be best.

 

[andyZ00m]

27 minutes ago, datzenmike said:

Check and snug (not over tighten) the clamps while the hoses are warm and soft.

 

I would flush the block as the coolant is shared with it and the heater core. Run a garden hose in both directions through the core with it set in the HOT position.

 

 

 

 

Polly bushings are not compliant enough for use on the tension rods. The bushing should flex during suspension movement. Polly will force the tension rod to flex and this can lead to metal fatigue and breakage. You may want to drill a few holes to allow up and down flexing. Compression will not be affected. Rubber replacements would be best.

 

 

Nice idea with the heater core flushing. It had some seriously nasty shit in there and I have a feeling I didnt get it all out just by draining through the radiator.

 

Im trying to find rubber bushings that will work. Maybe I can take off the ones I have now and take em to the parts store and see if I can find replacements in rubber that are similar.

[banzai510(hainz)]

use rubber ones strut rod bushing or shock tower bushing

[bilzbobaggins]

I think I used sway bar link bushings on mine.

[Crashtd420]

14 hours ago, bilzbobaggins said:

I think I used sway bar link bushings on mine.

Same

[andyZ00m]

Anyone know where to find the hood rubber bumpers for the 521? I’m missing one and the rest are blasted.

 

it’s still fucking raining here so can’t work on the truck really right now but I got all the suspension bushings and parts ready when it’s dry again in a couple days. 

Edited December 30, 2023 by andyZ00m

[mrbigtanker]

1 hour ago, andyZ00m said:

Anyone know where to find the hood rubber bumpers for the 521? I’m missing one and the rest are blasted.

 

it’s still fucking raining here so can’t work on the truck really right now but I got all the suspension bushings and parts ready when it’s dry again in a couple days. 

datsungarage.com 

[mrbigtanker]

https://www.datsun-garage.com/collections/datsun-520-521-weatherstrip-and-rubber/products/hood-bumper-set-1966-72-520-521

[andyZ00m]

12 hours ago, mrbigtanker said:

https://www.datsun-garage.com/collections/datsun-520-521-weatherstrip-and-rubber/products/hood-bumper-set-1966-72-520-521

ohhhhhhhh yes! Thank you!

[andyZ00m]

Got the hesitation issue sorted. Went with bigger main jets (which didnt make sense to me but fixed it) from the recommendation of the carb wizard. went to 175/180. Probably lost some mpg but thats ok. Motor running great and timing/idle/mix dialed.

 

Got the adapter to put the stock air filter on there and its BARELY fitting under the hood. Had to put a little rubber furniture foot on the hood where it was rubbing the tiniest bit.

 

Edited December 30, 2023 by andyZ00m

[banzai510(hainz)]

the carb WEBER adpaters actuall raises the stock airflilter up. this is real common on L20b as its a taller motor. But weber makes a 1.75 in tall airfilter

[andyZ00m]

1 hour ago, banzai510(hainz) said:

the carb WEBER adpaters actuall raises the stock airflilter up. this is real common on L20b as its a taller motor. But weber makes a 1.75 in tall airfilter

yeah exactly what’s happening. The rectangular air filter that came with it fit fine but made it look all hot rod. Which would be fine but I’m gunna try and make This work for now. 
 

make sense that with a l20b it would be exactly 1” worse. Haha. 

[andyZ00m]

Replaced the stabilizer bars/bushings and the front shocks today. Def driving tighter. The new shocks make it sit just a little bit higher. No worries there for me.

 

I have been noticing a slight vibration when braking and since I had the wheels off I looked at the new brake pads/shoes and there is a weird wear pattern. Not sure what could be causing this but it def explains the vibration. Any ideas?

 

It looks the same on both sides. Maybe bad drums from the factory?

 

Edited January 2 by andyZ00m

[andyZ00m]

I put the old drums back on and the brakes are smooth af.

 

New drums are clearly garbagio. Gunna take em to the shop and have them rounded out, theres a place right down the street from me that does it.

 

These are supposed to be the high quality drums too... oh well.

 

Also, had to go back to the Weber air filter as there just isnt enough room for the stock air filter under the hood after the adapter. The hood was rattling all over it and making a huge racket. It looks a lot cleaner, just not stock at all. Also means I need to rig up the valve cover vent and the fuel tank vapor line.

Edited January 2 by andyZ00m

[andyZ00m]

Heyo! Getting back to work on the truck.

 

Im going to have the seat reupholstered and since I will have the seat out of the truck for a couple weeks I thought I would also tackle adding three point seat belts. My wife already hates the lack of modern safety and I cant put my kids seats in this thing without them.

 

I found this thread which is awesome but wondering if anyone has done this recently and if they found an offthe shelf solution for the nut that goes inside the pillar? I could have something fabricated if thats necessary.

 

My truck has the little flat spots on the b pillar but I dont know if there are threads in there. Do I just drill a hole and see if its threaded? Whats the best way to tackle this?

 

I plan to use these belts. https://www.seatbeltplanet.com/i-30499408-1968-1972-datsun-521-driver-or-passenger-bench-seat-belt.html?ref=category:1389706

 

Thanks for the advice!

[Crashtd420]

49 minutes ago, andyZ00m said:

Heyo! Getting back to work on the truck.

 

Im going to have the seat reupholstered and since I will have the seat out of the truck for a couple weeks I thought I would also tackle adding three point seat belts. My wife already hates the lack of modern safety and I cant put my kids seats in this thing without them.

 

I found this thread which is awesome but wondering if anyone has done this recently and if they found an offthe shelf solution for the nut that goes inside the pillar? I could have something fabricated if thats necessary.

 

My truck has the little flat spots on the b pillar but I dont know if there are threads in there. Do I just drill a hole and see if its threaded? Whats the best way to tackle this?

 

I plan to use these belts. https://www.seatbeltplanet.com/i-30499408-1968-1972-datsun-521-driver-or-passenger-bench-seat-belt.html?ref=category:1389706

 

Thanks for the advice!

They definitely didnt have those listed 5 years ago... mine being a 72 has the 3rd point there... if its not there then there is nothing in there.... they sell plates that can be bolted inside... 

You drill a hole lower to fish it up....

 

Search for 3 point seatbelt anchor plate...

 

 

 

You really just need this plate

 

 

 

Edited January 10 by Crashtd420

[Crashtd420]

50 minutes ago, andyZ00m said:

 

I found this thread which is awesome but wondering if anyone has done this recently

Just realized this is a link....

And yes that's basically what you need to do...