Stock NIKKI questions...
03-07-09, 12:47 PM
#1
Stock NIKKI questions...
I have a GSL-SE that sat for AWHILE & I'm slowly bringing back to life. She has a 12A in her.
I named her Ol'Dirty... Here's a pic:
The Mikuni carb that was on her is solidly frozen stuck from sitting for so long, so I decided to ditch the Mikuni for now and drop a stock 85 NIKKI on her.
Anyways... The car is going to be a weekend street driver w/NO emissions.
Here's the lower intake manifold:
Anything I should do to prep, get rid of, block off, etc...???
What is that flap door thing in the bottom pic, top left port...??
Are the coolant passages necessary or should I block them off...?
I named her Ol'Dirty... Here's a pic:
The Mikuni carb that was on her is solidly frozen stuck from sitting for so long, so I decided to ditch the Mikuni for now and drop a stock 85 NIKKI on her.
Anyways... The car is going to be a weekend street driver w/NO emissions.
Here's the lower intake manifold:
Anything I should do to prep, get rid of, block off, etc...???
What is that flap door thing in the bottom pic, top left port...??
Are the coolant passages necessary or should I block them off...?
03-07-09, 02:18 PM
#4
My 7 is my girlfriend.
iTrader: (5)
Join Date: Feb 2006
Location: London, Ontario, Canada
Posts: 3,162
Likes: 0
Received 1 Like
on
1 Post
That flap thing is the shutter valve. Designed to eliminate backfire from the rear rotor on deceleration. That ACV is the opening on the side under where the carb bolts on. Go to www.mazspeed.com and check out the de-emission tutorial. That will show you what to block off/remove. You can also remove that shutter valve by pulling the valve out of the shaft and then pulling the shaft out of the manifold. Then measure the shaft length you need for a plug and cut the rest off. Use JB Weld to hold the new plug in and don't be stingy. You don't want any leaks. I removed mine last year and have no problems with backfires. It's just an obstruction that doesn't need to be there anymore. Also if your car came with a 12A, those wheels which look like they would be 4X110 bolt pattern, and 4 wheel discs, then it is at best a GSL. The GSL-SE came with a fuel injected 13B and 4X114.3 bolt pattern with 14 inch wheels. Take the Mikuni and stick in a bucket of carb cleaner. That may help loosen it up then you can rebuild it and get some oomph out of it. Or buy a Sterling 465 and enjoy stock like driveability with some extra power to boot. www.sterlingmetalworks.com . There's also some great theory and whatnot there to help you understand more about the Nikki and how it works.
03-07-09, 04:40 PM
#5
Zoom Zoom
iTrader: (1)
Join Date: Jun 2008
Location: Minnesota
Posts: 638
Likes: 0
Received 0 Likes
on
0 Posts
What you have isn't a SE. SE's had a 13B and different bolt pattern. Look at your rear wheels. If you have drums, then you have a S or GS, and if you have discs, then you have a GSL (and LSD).
I wouldn't bother with all the time associated getting a Nikki back on there. The Mikuni may need a rebuild but in the end it will provide better perfomance than the stock Nikki.
I wouldn't bother with all the time associated getting a Nikki back on there. The Mikuni may need a rebuild but in the end it will provide better perfomance than the stock Nikki.
03-07-09, 04:48 PM
#6
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,852
Received 2,615 Likes
on
1,852 Posts
it does have gsl-se seats in it, and those wheels were made in 4x114.3 for the 510's
03-07-09, 07:46 PM
#7
THE RX HORDER... REALLY.
Join Date: Mar 2009
Location: Long Island
Posts: 7
Likes: 0
Received 0 Likes
on
0 Posts
It's definatly a SE. The car is actually mine and 85TIIDEVIL talked me out of parting her out. The owner before me pulled the 13B and fuel injection for a 12A carb set-up. The car sat for 6 years and the mikuni throttle is still frozen after we've been soaking it for agood month already.
Trending Topics
03-10-09, 12:39 AM
#9
^ Sometimes u do what u have to do to get going again, especially on a budget...
Thanks a bunch ORION for the help.
So do I block off the coolant passages...??
And the black plastic shield that goes btwn the intake and the carb... Should I gasketmaker her up..? It appears there is a gasket on both sides that seems fully intact but it's kinda hard.
And there's a big ol' nipple right under the ******* valve thats capped off with a rubber plug. Is that a vaccum source if uncapped..?
Still have to check out the MAZSPEED site. My ADOBE wouldn't load correctly..?
Thanks a bunch ORION for the help.
So do I block off the coolant passages...??
And the black plastic shield that goes btwn the intake and the carb... Should I gasketmaker her up..? It appears there is a gasket on both sides that seems fully intact but it's kinda hard.
And there's a big ol' nipple right under the ******* valve thats capped off with a rubber plug. Is that a vaccum source if uncapped..?
Still have to check out the MAZSPEED site. My ADOBE wouldn't load correctly..?
03-10-09, 02:55 AM
#10
On a stock 12a, you shouldn't block the coolant passages. But i would replace the intake manifold gasket, and with that comes new coolant passage o-rings. Would be a highly recommended step imo.
The plastic shield does not need a new gasket, it is a gasket in itself.
The nipples you are not using on the carb should be plugged. This is dependent on whether you're removing the emissions, have AC, etc.
Ian
The plastic shield does not need a new gasket, it is a gasket in itself.
The nipples you are not using on the carb should be plugged. This is dependent on whether you're removing the emissions, have AC, etc.
Ian
03-10-09, 07:23 AM
#12
haha...
All the RacingBeat manifolds basicly block them suckers off, so they can't be that important...??
I can't recall hearing / reading what coolant passing threw the intake was all about...? It's gotta heat up the manifold for some reason...? I'm basicly trying to understand why I'm either keeping or removing it...
All the RacingBeat manifolds basicly block them suckers off, so they can't be that important...??
I can't recall hearing / reading what coolant passing threw the intake was all about...? It's gotta heat up the manifold for some reason...? I'm basicly trying to understand why I'm either keeping or removing it...
03-10-09, 10:10 AM
#13
The coolant passage thru the manifold is meant to stabilize carb temperature; help it warm up early, prevent it from getting too hot.
Lots of people have blocked off the cooling passages (on the rotor housing side, usually, with proper-sized freeze plugs) without ill effect. Makes removing the manifold much less of a chore, too.
Lots of people have blocked off the cooling passages (on the rotor housing side, usually, with proper-sized freeze plugs) without ill effect. Makes removing the manifold much less of a chore, too.
03-11-09, 08:47 AM
#15
^ I'm definatly all for anything being less of a chore. Off to the parts store w/a spare housing to find me some freeze out plugs.
Here's a few pics to keep the update on my progress... Even though they are simple tasks, pictures say alot more then words sometimes.
The screws removing the shutter weren't so willing to part ways...
So I attacked them with a small dremel cutting wheel...
Then a drillbit...
After getting it out I cut the shaft to size to plug the hole...
And plugged her back up w/some JB Weld...
Then cut off I what guess you'd call the vacuum pot...
And turned it into a block off plate...
Here's a few pics to keep the update on my progress... Even though they are simple tasks, pictures say alot more then words sometimes.
The screws removing the shutter weren't so willing to part ways...
So I attacked them with a small dremel cutting wheel...
Then a drillbit...
After getting it out I cut the shaft to size to plug the hole...
And plugged her back up w/some JB Weld...
Then cut off I what guess you'd call the vacuum pot...
And turned it into a block off plate...
03-11-09, 10:28 AM
#16
The screws on throttle plates in many carbs have what are called "disturbed" threads; essentially, they are peened at the bottom or precisely overtightened just enough to lock them in place, and prevent them from falling out (which would obviously be bad). The Mazda carb manual mentions this, as being the reason normal shop servicepeople were not supposed to remove the butterflies during rebuild.
Wouldn't be surprised to find the same thing was done to the shutter valve.
Wouldn't be surprised to find the same thing was done to the shutter valve.
03-11-09, 03:35 PM
#17
Moderator
iTrader: (3)
Join Date: Mar 2001
Location: https://www2.mazda.com/en/100th/
Posts: 30,852
Received 2,615 Likes
on
1,852 Posts
its also a huge giant PITA to try to align 4 throttle plates
03-11-09, 07:18 PM
#18
Alrighty...
So what I've just learned if you are a cheap bastard you can save yourself the $1 each if you re-use the small freeze out plugs on the front plate of a 2nd gen housing...
Or you can save yourself the time of trying out a dozen freeze out plugs @ the parts store until you find the right one by just ordering one from a front plate of a 2ndgen housing.
This is to plug the coolant passages on a 12A rotor housing of course...
So what I've just learned if you are a cheap bastard you can save yourself the $1 each if you re-use the small freeze out plugs on the front plate of a 2nd gen housing...
Or you can save yourself the time of trying out a dozen freeze out plugs @ the parts store until you find the right one by just ordering one from a front plate of a 2ndgen housing.
This is to plug the coolant passages on a 12A rotor housing of course...
03-11-09, 08:21 PM
#19
Ohhh man... I just finished taking a look a three stock carbs I have and them things scare me.
There's a TON of stuff & I have no clue what's what.
I have a completly stock nikki I rebuilt about 5 years ago and I have no clue if I did it right...
I have another one that's never been molested but a bunch of little things are missing here and there...
And then I have another one completely stock, compleletly unmolested that's on my 12A I pulled a few years back that I use alot for a reference since it's still connected to the motor w/all the vaccuum and emmision lines still 100% intact. But at least I know she runs / ran fine.
Sorry for thinking out loud but I'm a bit nervous which one I should try.
There's a TON of stuff & I have no clue what's what.
I have a completly stock nikki I rebuilt about 5 years ago and I have no clue if I did it right...
I have another one that's never been molested but a bunch of little things are missing here and there...
And then I have another one completely stock, compleletly unmolested that's on my 12A I pulled a few years back that I use alot for a reference since it's still connected to the motor w/all the vaccuum and emmision lines still 100% intact. But at least I know she runs / ran fine.
Sorry for thinking out loud but I'm a bit nervous which one I should try.
03-11-09, 08:33 PM
#20
Chad Carson
iTrader: (29)
Join Date: Nov 2001
Location: South of Nashville TN. USA
Posts: 7,010
Likes: 0
Received 0 Likes
on
0 Posts
That flap thing is the shutter valve. Designed to eliminate backfire from the rear rotor on deceleration. That ACV is the opening on the side under where the carb bolts on. Go to www.mazspeed.com and check out the de-emission tutorial. That will show you what to block off/remove. You can also remove that shutter valve by pulling the valve out of the shaft and then pulling the shaft out of the manifold. Then measure the shaft length you need for a plug and cut the rest off. Use JB Weld to hold the new plug in and don't be stingy. You don't want any leaks. I removed mine last year and have no problems with backfires. It's just an obstruction that doesn't need to be there anymore. Also if your car came with a 12A, those wheels which look like they would be 4X110 bolt pattern, and 4 wheel discs, then it is at best a GSL. The GSL-SE came with a fuel injected 13B and 4X114.3 bolt pattern with 14 inch wheels. Take the Mikuni and stick in a bucket of carb cleaner. That may help loosen it up then you can rebuild it and get some oomph out of it. Or buy a Sterling 465 and enjoy stock like driveability with some extra power to boot. www.sterlingmetalworks.com . There's also some great theory and whatnot there to help you understand more about the Nikki and how it works.
What Orion ^^^ said exactly! I would soak the carb more as it might unstick and would be better than the stock carb. Might try kerosene or parts blaster
03-11-09, 10:26 PM
#22
Is there anyway someone can copy and paste the tutorial on MAZSPEED here, email me, print it out and drop in the mail, (j/k) something,..???
I've tried to upload a new ADOBE and still keep crashing...???
Fire... I'm going to get the Mikuini unfroze eventually but I have a YAW on my car and that puppy kicks ***. Besides the fact I get to learn about my carb at the same time, I want to also be able to compare the two and see if the Mikuni really is all that much better or vise versa.
I've tried to upload a new ADOBE and still keep crashing...???
Fire... I'm going to get the Mikuini unfroze eventually but I have a YAW on my car and that puppy kicks ***. Besides the fact I get to learn about my carb at the same time, I want to also be able to compare the two and see if the Mikuni really is all that much better or vise versa.
03-12-09, 01:27 AM
#24
adobe reader sucks big *****......get Foxit Reader http://www.foxitsoftware.com/pdf/reader/
03-12-09, 08:14 AM
#25
I uploaded the new version of Adobe and the Mazspeed tutorial keeps opening up with the old one... I'm don't really want to upload another program that isn't going to work.
I'll just wait until the weekend and print it out at my pops house.
Anyways... here's a few more pics to keep it moving.
I put a small layer of the thin gasket maker on the heat shield b/c even though the gasket was all intact it was hard as could be. Also the shield was cracked so I repaired to prevent further cracking.
Nicey nice cleany clean...
I'll just wait until the weekend and print it out at my pops house.
Anyways... here's a few more pics to keep it moving.
I put a small layer of the thin gasket maker on the heat shield b/c even though the gasket was all intact it was hard as could be. Also the shield was cracked so I repaired to prevent further cracking.
Nicey nice cleany clean...