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Topic: carburetor opinions
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Ryan in Seattle
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bullet Topic: carburetor opinions
    Posted: 17 April 2005 at 11:15am

So since Bleach and I dropped in my latest l20b, I've been having a hell of a time getting it to run correctly. At first I thought I f**ked the timingup again, but after checking it over and over, turns out I actually handled it correctly for once. Blahblah, my weber is causing me all of the headaches. this I know for a fact. I took it apart yesterday for the 306th time, adjusted the floats, and bam! the secondary opened up and for a brief, beautiful second, I got to feel the power that my L20 can provide. well sh*t, it's not the engine at all! I built a solid L20!!!! then the truck died, I pushed it out of the intersection, pulled over and, wow, I didn't know you could fit so much gas into a carb. Seriously flooded, floats were way off. No biggie, adjusted them back, and I'm back to square one. It drives fine until i try to open up the secondary, then apparently it starves. But i cleaned all of the jets, so that's not it. Must be deep inside.

Anyways. I've got a great deal in the works over a 38/38. Supposedly solid. Has anyone ever tried one of these carbs on an l20? It seems to me that it is close to the equivalent of flattop 38mm su carbs, the bores are the same, they essentially open at the same time, just my setup would be a downflow vs. sidedraft. Any opinions, ideas, or feedback? Please?

1973 620 "Prerunner"
L20B,A87,5spd.Lynx,40dcoe,
header,cammed & bored.
zx oil pump,starter,headbolts
& water pump/pulley.
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Bleach
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bullet Posted: 17 April 2005 at 5:00pm
with an offy and the mild porting you did, I'd say dont' get greedy and go with a larger non-progressive carb. Another Weber or NEW weber will have all the parts in place and you need to have your choke on there too.
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808DA6
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bullet Posted: 18 April 2005 at 5:15pm

I thought about doing the 38/38 DGES myself.  Pricey though.  I decided to go with a 42 DCNF.  Simple carb.  I was having similar probs w/ my 32/36 except mine leaned out real bad on the primary side.  I have a spare 40 DCNF if you want to try it.  You'll have to make an adapter for it.  Not for sale though.  If  you like it, there pretty easy to find for cheap.

BTW, this carb will be mated to a stock L16 w/ a 280/480 cam and an offy manifold.  Later I will have a closed chambered head machined for it as well.

~B

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Hainz
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bullet Posted: 18 April 2005 at 11:00pm
808DA6
some sidedrafts will enhance that cam grind you have

Ryan I told Bleach that your carb was hosed when I was there the first time you did your motor. I think its time to get another one(not someone elses junk)
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Ryan in Seattle
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bullet Posted: 18 April 2005 at 11:17pm
I'm looking for a good 3236. the one i have has seen better days. at first i was considering a 3838, but i don't want anymore headaches. If i got the 3838, i'd have to open up the manifold to allow the butterflies to open. i just want to find a solid weber3236. period. if you have a solid one that you know has no problems, pm me. we'll talk, I'm tired of f**king around. i want dependability. my motor is solid (finally), no cheezy sh*t goin on there, just the carb has had it.
1973 620 "Prerunner"
L20B,A87,5spd.Lynx,40dcoe,
header,cammed & bored.
zx oil pump,starter,headbolts
& water pump/pulley.
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Ryan in Seattle
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bullet Posted: 18 April 2005 at 11:19pm
or a solid set of su's that don't need any work. I'll consider partial trade of my port and polished Offenhauser manifold. either or, no more headaches, no custom adaptors, no porting, no poo
1973 620 "Prerunner"
L20B,A87,5spd.Lynx,40dcoe,
header,cammed & bored.
zx oil pump,starter,headbolts
& water pump/pulley.
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Ryan in Seattle
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bullet Posted: 18 April 2005 at 11:20pm
And i want a choke, i removed my other one, stupidly. then I'll be able to start saving for a cam, lifters, and retainers.
1973 620 "Prerunner"
L20B,A87,5spd.Lynx,40dcoe,
header,cammed & bored.
zx oil pump,starter,headbolts
& water pump/pulley.
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Hainz
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bullet Posted: 18 April 2005 at 11:43pm
http://www.webercarbsdirect.com/inc/pdetail?v=1&pid=566

just for you!!!!!!!!!!!!!!!http://www.webercarbsdirect.com/inc/pdetail?v=1&pid=566

this be the one with the cut off soiliniod
http://www.webercarbsdirect.com/inc/pdetail?v=1&pid=398
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74wagon710
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bullet Posted: 19 April 2005 at 12:02am

You wont have to open up the intake to use a 38/38, the one on my L18 did not need any mods to fit once the adaptor was on and it is the short one.  The only porting you may want to do is cutting the seperate holes out to make one large oval hole for more direct flow. My carb also has a working electric choke.

74 Datsun 710 wagon, all original now, near perfect shape, project vehicle now.

83 Hell Camino.

07 Civic Si Coupe.

07 Yamaha R1
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74wagon710
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bullet Posted: 19 April 2005 at 12:05am
The carbs Hainz linked to have the same filter and adaptor I have. You do not need the accelerator linkage adaptors so that will save you money.  Just swap over the  throttle arm on your stock hitachi or your current junk weber to the new carb and you ready to go.
74 Datsun 710 wagon, all original now, near perfect shape, project vehicle now.

83 Hell Camino.

07 Civic Si Coupe.

07 Yamaha R1
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VilleBill
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bullet Posted: 19 April 2005 at 10:03am
Is there some way to determine if a used weber is used up? Before I throw $ into a rebuild kit and jets. What gos bad?

Thanks
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Hainz
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bullet Posted: 19 April 2005 at 10:35am
Well Ryans carb has no choke and he didnt route a water line to the intake since his L20 had no water passage holes. So it would take a while to warm up.
His motor was timed correct and it just looke like the carb was poping alot so I assumed it was the proplem.
personally there is not much to them. Mine are well used and still work good as long you you dont take it apart and lay it on the floats and bend the arms and keep the jets clean. But sometimes its best to get a new one and start with a clean slate. esp if you have a new motor then youll be good to go for awhile.
Mine DGV has no choke ,but rev it up and it pretty much idles right away.
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mklotz70
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bullet Posted: 19 April 2005 at 12:05pm
As long as you don't bend, warp, or break anything like Hainz said, about the only thing that can go wrong with them is the holes for the butterfly shaft get worn excessively and it causes an erratic vacuum leak. Makes it hard to keep a good idle. You can have bushing put in them, but the cost may not be worth it. I put a bushing in another guys stock carb a couple of weeks ago and it took about 4 hours just to do the one. To do it right, you'd have to do at least the two for the main barrel....secondaries probably won't be worn out anyway. The other thing that can cause grief with the weber....and I just learned this about 10min ago while working on mine.....the holes for the choke shaft can get worn, allowing the choke butterflies to rub against the side of the barrel. Once the choke is open it isn't a prob, but with the choke closed, they stick when I try to get into the secondary.

Don't have to be too bright to be me!
Gresham, OR
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datsunfish
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bullet Posted: 19 April 2005 at 8:53pm

I have a few webers and have had even the most worn ones work fine.As long as it is clean and the float adjusted correctly.

I have ran a larger hibachi(for naps Z) before with no run on problems and plenty of power for a stock l20b.I have even fabbed up a mechanical secondary and removed the vacuum assembly.You can also just remove the vacuum spring for less restriction.Remove all unnecessary junk.

The thing that sucks about the hitachi is all the parts bbs and such.Good but not as cool as a weber.

71 510 4 door
72 521
72.5 620
73 VW
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mklotz70
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bullet Posted: 20 April 2005 at 10:14am
You're right about working fine with wear.....when they get so sloppy that the butterflies have trouble centering.....that's when the shafts are too loose. No wiggle on the shaft is best, but some wiggle is pretty common. The carb I put the bushing in had about a 1/16" of play in the hole.
Don't have to be too bright to be me!
Gresham, OR
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