1st Generation Specific (1979-1985) 1979-1985 Discussion including performance modifications and technical support sections

What is this part? Carb bushing?

Thread Tools
 
Search this Thread
 
Old 06-27-17, 10:26 AM
  #1  
Full Member
Thread Starter
 
rithsleeper's Avatar
 
Join Date: Oct 2012
Location: sumter sc
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
What is this part? Carb bushing?

Ok, so the car sat for 2 years so I was draining the gas and cleaning the carb when I went to shake a jet out of the top and this little bugger fell out onto the bench. I have no idea where it came from. The only place that I thought it might fit would be under the accelerator jet but the piece makes no sense. I started the car without it in the carb and seemed to run fine... But I'm betting if mazda put it in there, it must do something. That pin sized hole doesn't look stock but it goes all the way through.

Name:  received_10105399020830897.jpeg
Views: 288
Size:  42.5 KBName:  received_10105399019393777.jpeg
Views: 291
Size:  50.2 KBName:  received_10105399019962637.jpeg
Views: 284
Size:  43.6 KB
Old 06-27-17, 04:30 PM
  #2  
Full Member
 
workaholic's Avatar
 
Join Date: Jun 2017
Location: Pittsburgh, PA
Posts: 73
Received 1 Like on 1 Post
Looks like one of the little weights that go in the carb, but if it was under the jet, it was in the wrong place...
Old 06-28-17, 09:14 AM
  #3  
Full Member
Thread Starter
 
rithsleeper's Avatar
 
Join Date: Oct 2012
Location: sumter sc
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
It did not come from under a jet. It fell out of somewhere while I was shaking a jet out. I didn't see where it came from. I was holding the carb in my hand so I am fairly confident it came from the carb... Can you be a bit more specific on where the "weight" is supposed to be?
Old 06-28-17, 08:37 PM
  #4  
1st-Class Engine Janitor

iTrader: (15)
 
DivinDriver's Avatar
 
Join Date: Jun 2008
Location: Chino Hills, CA
Posts: 8,376
Received 26 Likes on 24 Posts
Check ball weight, looks like. Part of the accelerator pump circuit, it's supposed to sit on top of the accel pump outlet check ball to make it close better.

There should have been a small check ball under it, too - though sometimes they get stuck from dried fuel varnish.

Exactly where it goes depends on your version of the carb (some carbs have two) but it probably came from under the accel pump outlets.

Don't believe I've ever seen one with a hole in it, though.
Old 06-28-17, 11:42 PM
  #5  
Lapping = Fapping

iTrader: (13)
 
Jeff20B's Avatar
 
Join Date: Aug 2001
Location: Near Seattle
Posts: 15,725
Received 70 Likes on 64 Posts
I betcha someone drilled that to create an anti-siphon effect, probably due to an accel pump that was drawing fuel out at sustained high revs. It's similar to a problem experienced by Holley users. I doubt this mod worked very well but who knows. He should have looked elsewhere in the carb to solve his problem such as making sure both checkballs and both brass weights are there.

By the way, I think all Nikkis had them, not just some models.
Old 07-01-17, 04:49 PM
  #6  
1st-Class Engine Janitor

iTrader: (15)
 
DivinDriver's Avatar
 
Join Date: Jun 2008
Location: Chino Hills, CA
Posts: 8,376
Received 26 Likes on 24 Posts
Originally Posted by Jeff20B
By the way, I think all Nikkis had them, not just some models.
Was of the impression that some models had one, others two, but that's an old memory and by no means reliable.

I know mine has two weights; a large one and a small thin one.

Edit: I checked, looks like all Nikkis have two, Power Valve Inlet (small) and Power Valve Outlet (large).

The one in the OP's pic is the large one, for under the outlet jets.

Last edited by DivinDriver; 07-01-17 at 05:38 PM.
Old 07-19-17, 06:55 PM
  #7  
Full Member
Thread Starter
 
rithsleeper's Avatar
 
Join Date: Oct 2012
Location: sumter sc
Posts: 72
Likes: 0
Received 0 Likes on 0 Posts
thanks guys for the response. This actually seems pretty helpful. I didn't see a ball valve under but the carb kit came with a few ball bearings. I'm hoping there isn't that big of a difference between them. I would like to find the second weight so I know it is there also.

This is on a IT7 car so I'm at high rpms all the time, so the hole makes sense.
Old 07-21-17, 11:00 AM
  #8  
1st-Class Engine Janitor

iTrader: (15)
 
DivinDriver's Avatar
 
Join Date: Jun 2008
Location: Chino Hills, CA
Posts: 8,376
Received 26 Likes on 24 Posts
I have personal experience with the check ball getting stuck at the bottom of the bore due to fuel deposits. Solution was to use a magnetized ice pick to gently work it loose.

You could use compressed air at the other end of the channel... but the ball may end up shooting the cat in the yard.
Old 07-21-17, 01:59 PM
  #9  
Waffles - hmmm good

iTrader: (1)
 
t_g_farrell's Avatar
 
Join Date: Jul 2004
Location: Lake Wylie, N.C.
Posts: 8,783
Received 282 Likes on 232 Posts
Originally Posted by DivinDriver
You could use compressed air at the other end of the channel... but the ball may end up shooting the cat in the yard.
And thats bad how?
Old 07-22-17, 01:28 PM
  #10  
1st-Class Engine Janitor

iTrader: (15)
 
DivinDriver's Avatar
 
Join Date: Jun 2008
Location: Chino Hills, CA
Posts: 8,376
Received 26 Likes on 24 Posts
Originally Posted by t_g_farrell
And thats bad how?
Ask the cat.




All times are GMT -5. The time now is 12:18 AM.