snwyvern

Yeah... so... About those carburetors. I, having read whatever I can find in the FAQ (that doesn't have a broken link...) embarked upon rebuilding my 7's stock carb, and, after much pain and agony did so.

... The secondary venturis are filling with fuel. And- When I say filling, I mean filling; all the way up and over into the rest of the carburetor.


Any ideas?


Also... What's necessary to go buy an aftermarket carb and bolt it on?

Cheers,

rxtasy3

iTrader: (2)

pull the carb top back off and check the needle and seat to see if there's any trash gotten in the to keep it from shutting off the fuel, otherwise, the float level is probably set too high. as for aftermarket carb, there's several options. the majority here will tell u dellorto or webber. i'm running the holley setup from racing beat. reguardless which u got with, they're not cheap. check the f/s section here and they pop up on ebay from time to time.

lascelles

Go to http://www.sterlingmetalworks.com

Read the trouble shooting guide.
or buy the best carb for our cars

PS I don't get a cut just think he is good

snwyvern

I was hoping to get a "Hey, check your vent solenoid-retard!" or something similar... message... You know, something easy to fix :P

I'm just tired of troubleshooting, I want this car to run, and I want it to run today... But, alack! I'll probably just mothball it until August so I can buy a Sterling. Blah.

... and more blah.

Thank you all for your advice.

74RX4

iTrader: (10)

A strong tap or two on the top of the carb will sometimes break loose new or sticking needle valves. Did you replace needle valves when you rebuilt the carb?

Kentetsu

If you didn't adjust your floats during the rebuild, the don't touch them now either!!!!
The float levels will not change unless you mess with them, drop the carb, or something of that nature. But if they were okay before, then they should be okay now.

Sterling carbs rock!

Sterling is our resident carb expert, and his site has all kinds of details on rebuilding, troubleshooting, modifying, tuning, etc. Definitely take the time to read through some of his articles, or even sign up with his forum for help from the Carb God himself.

www.sterlingmetalworks.com (just in case you missed the link the first time)


.

DivinDriver

iTrader: (15)

I had this problem after my last rebuild - - turned out to be one needle that didn't like one seat bore. Swapped the needles left/right, problem went away.

When this happens, something is preventing the needle from seating, or it's not sealing.

Common causes:
*Extractor spring (litle spring that ties the float to the needle) is positioned wrong and is hanging up
*Spring inside the needle got left out - makes the needle too short to seat
*forgot to put the aluminum crush washer on the needle seat before installing, or it was out of position and didn't seat properly
*needle seat not tightened down properly

New needles are sort of notorious for binding until they wear in, too.


Or, your fuel pressue is waaaaaaaay too high; common problem with aftermarket pumps unless a regulator is used. Stock Nikkis only like 3 lbs or so of fuel pressure, and most aftermarket pumps are well above that. Too much fuel pressure overwhelms the floats, forcing the needles open

A blocked/restricted return line can do this, too, as can intalling the return line check valve backwards.

snwyvern

... This sounds promising. I'll give it a couple of whacks when I can get to it next. This would "explain" why it ran fine for a week or so (with shoddy ignition) before any issues cropped up.


And yes, all the parts are new. (except for the emulsion tubes, jets... so on.) I may have had an issue with the accelerator pump check spring and weight... But that would cause leaning out when stomping on the gas, not... niagra falls.

orthophonic

Here is a little trick that might help to get trash from between the float valve and its seat. Close off the fuel supply to the carburetor by pinching shut the rubber hose that feeds in the fuel. Start the car and let it run until the gasoline is exhausted in the carburetor and the engine will stall. Unpinch the fuel line and gasoline will enter the carburetor under some pressure and wash out the trash that was sticking the float valve open. That is about the easiest way that I have found to do it...

Kentetsu

You know, I can't say for certain, but I seem to recall that if you are missing one of those components for the accelerator pump it will cause niagra falls. Check with Sterling, he'll know for sure....

snwyvern

... I discovered that the mess that is 'supposed' to go under in the Accelerator Pump circuit is completely missing. Fail.

So... Does someone know what I need to ask the nice gentlemen at the parts' counter for?

-

snwyvern

Bump, for great justice?

DivinDriver

iTrader: (15)

Can you post a picture of the afflicted area, so we can get an idea of what specifically is missing?

jinxed4dub

iTrader: (7)

check ball and weight? that goes under the screw in the AP? If thats what your missing I don't think you can buy one from auto parts store. I'm sure someone has a spare from a dead carb. Look up RW-7 on the forum. I think he has a spare from when we were having problems with my carb.

kutukutu1

iTrader: (5)

hey my carb after the rebuild it was doing the same thing, the secondary where flooding to the max. it was that i had the bowl vent capped off. check if you plugged it by mistake

snwyvern

The "missing" parts are under the brass screw indicated in black.

I believe that the proper name for this is the "accelerator pump circuit."

Thanks.

DivinDriver

iTrader: (15)

Sadly, not sold separately by parts stores, as far as I know.

There are Mazda part numbers for them on the parts fiche. No idea of current availability, though; you'd need to contact a dealer to see what can still be had.

Or find someone with a junk carb that can spare them.

Kentetsu

Send Sterling a PM and see if he will take pity on you...

snwyvern

Bumping to indicate PMs being sent.

RW-7

iTrader: (56)

Replied to PM.

snwyvern

Bumping for an update. I replaced the missing parts (AP Circuit parts.) I took the carb. off of the vehicle to drop in the bits-- For obvious reasons. Prior to removing the carbeurator there was fuel drizzling from the secondaries. Now there's fuel pouring in everywhere. The sight-glasses on the carbeurator are all-the-way-filled with fuel.

Any "easy" ideas, before I bust out the sledge hammer?

yetterben

Can we assume stock fuel pump?
If aftermarket make sure you are only getting 2 or 3 psi max.

MAke sure return line is not plugged either

snwyvern

Yes, stock fuel pump. The return line is clear and the check valve works. (Blah...) I am planning to rig something up to replace the fuel bowl vent solenoid tomorrow. Unless anyone else has any ideas, I suppose it's worth a shot!

DivinDriver

iTrader: (15)

Sounds like a classic case of sticky needles to me; I had to fiddle with mine several times, post-rebuild, before they'd seat proper. Same issue with gas gushing & full bowls. Once I got them properly settled, all was well.

Got downright skillful at taking the carb cover off without taking it off the car, by the time I had it right. Frustrating, but character-building.

yetterben

does the vent solenoid click when 12v is applied ?