510 Su's

[240260280]

Something for you Hitachi 38mm SU guys and gals.

 

Enjoy!

HJL38W.pdf

[Captain Obvious]

Haha!! Thanks guys! I don't know about the little 38mm varieties, but there is plenty of meat on the Z flat tops. Just remember... Measure twice, cut once.

"I cut it twice, and it's still too short." is often heard around my shop. 

Someday I'll have a pic of a car with uber-round tops installed.

[Patcon]

@zKars

I have two questions:

What are you doing for a choke cable for your new carbs?

It appears the heat shield is installed behind the carb and before the insulator. Did you put a gasket on each side of the heat shield? Did you put a gasket between the insulator and the manifold?

Well maybe three questions...

[zKars]

Good question. Three possibilities. There is a 510 specific two choke cable, which I "think" I have one somewhere that needs work. If I use a Z console like I did on my 69,  I can just use a Z cable and mount it in the console.

Last I've been trying to dream up a linkage "thingy" that converts the dual carb chokes into a single cable for 510's since the "right" one is nearly un-obtainium. Maybe some cold night the right simple design will come to me. I keep thinking of stepper motors....

Heat shield. yes, 6 gaskets, both sides of heat shield and insulators. The back of the heat shield has gold reflective foil on it You're trying to block radiant heat directly between the header and float bowls, can't stop circulating heated air from getting around the heat shield without getting really boxy around the entire carb/fender area. Line of site baby.

Edited December 19, 2017 by zKars

[Patcon]

 

10 hours ago, zKars said:

Good question. Three possibilities. There is a 510 specific two choke cable, which I "think" I have one somewhere that needs work. If I use a Z console like I did on my 69,  I can just use a Z cable and mount it in the console.

Last I've been trying to dream up a linkage "thingy" that converts the dual carb chokes into a single cable for 510's since the "right" one is nearly un-obtainium. Maybe some cold night the right simple design will come to me. I keep thinking of stepper motors....

Thanks Jim,

If you find the stock 510 cable, post up some pictures, maybe I can fabricate something. I would also like to see your final choke cable as well as your 240z center console hybridization. Cody wants a  console but I don't have a plan for that yet...

FYI I was able to get some misc parts and a heat shield from Z Therapy...

[Patcon]

OK, I need some help now. I am working on Cody's SU's. I got the front one apart, cleaned, replated and reassembled. The screws were stupid tight on the dome when I disassembled it. The problem I have is when I tighten the dome down the piston doesn't want to slide. If I leave them loose it's fine. So now what? Was trying to get these done by Christmas...

[zKars]

Oh oh. Start with checking if the needle is bent and rubbing on the jet tube. 

Try torquing down the dome screws in a slightly different order. Can it be put on 180 degrees rotated? 

Maybe hold the piston up with your finger as you tighten it down?

Has the plating added thickness somewhere where it shouldn't have?

Add some oil?

Edited December 20, 2017 by zKars

[Patcon]

2 minutes ago, zKars said:

Oh oh. Start with checking if the needle is bent and rubbing on the jet tube. 

Try torquing down the dome screws in a slightly different order. Can it be put on 180 degrees rotated? 

Maybe hold the piston up with your finger as you tighten it down?

Has the plating added thickness somewhere where it shouldn't have?

Add some oil?

The needle is brand new. I thought about taking it out and try that to at least isolate the problem. I added some oil to the dampener chamber. The dome can only go on one way. I tried the tighten while lifting the piston technique, that is how I isolated the issue. There is nothing I plated that should cause this issue...

[zKars]

Oh sure, now the ideas get pretty thin and sketchy...

Didn't mix up the domes/piston sets?

Check for the tinest burrs, nicks, spider webs, nose hairs, something that's causing the dome to go on crooked....

Lather it all up inside with tons of damper oil? 

Color the piston all over with sharpy then get it to stick, then look for where it's touching by where the sharpy is wore off.

Enlarge those holes where the locator pins fit to give you more position adjustment. Make whereever locates the dome looser or freer

Edited December 20, 2017 by zKars

[Patcon]

7 minutes ago, zKars said:

Oh sure, now the ideas get pretty thin and sketchy...

Didn't mix up the domes/piston sets?

Check for the tinest burrs, nicks, spider webs, nose hairs, something that's causing the dome to go on crooked....

Lather it all up inside with tons of damper oil? 

Color the piston all over with sharpy then get it to stick, then look for where it's touching by where the sharpy is wore off.

Enlarge those holes where the locator pins fit to give you more position adjustment. Make whereever locates the dome looser or freer

If I remember correctly it operated correctly before disassembly. I wondered if the previous owner had mixed up the domes and then compensated by torquing the screws down. I thought I might try the other dome after I get it clean. Really frustrated by this! It looks good now but isn't gonna work the way it is...

Why can't it just be simple?

@240260280

Any ideas Philip?

[240260280]

Good Talking.

Attached is SSS carb manual excerpt.   Apparently there are plastic replacements for those brass floats.

Datsun 510 SSS Carb.pdf

[240260280]

Also check this and post #7