chris_g

iTrader: (29)

Hey guys -

This has been my issue for a while and now its getting to the point where Im just going to spend the money to get it fixed....

I bought a Sterling Carb from a member on here, but somewhere down the line either Canada Post or USPS dropped it bending part of the throttle assembly. Its all fixed now, but Im thinking something else may be screwed up.

I am still not able to get the dang thing to idle under 2300

I figured if I post here, this time with more pictures so people can verify I am doing things correctly, I will eliminate all issues bit by bit.

• The timing seems to be decent. I removed the dizzy, lined up the two notches, plugged it in (making sure the rotor doesnt turn) and all seems to line up okay.
  
• Both ignitors are working. I checked with the timing light to make sure a signal was being sent and all wires are pulling one.
  
• I am running 2.7ish psi for fuel through my regulator
  
• All vacuum lines have been replaced with new ones
  
• My compression was around 90 I believe on both rotors, all seals. Ill have to check my other thread to verify. It was fine though, so thats the important part.

After running for a little while, my header begins to glow at the rear rotor which is making me believe ignition is wrong or the engine is running too lean.




Anyways, I stripped the intake and here's what I have currently. Is any of this wrong?






And here is my vacuum advance routing.

Tab on end which leads to the T in the following picture and then the two vacuum pots.




Thanks to all of those who can contribute, I'd like to get this thing running by spring.
Chris

Jeff20B

iTrader: (13)

I see a 76-78 gasket. You might need to get a 74-75/81-85 gasket to prevent an anoying exhaust leak from the ACV port. Best option is to get some quicksteel putty and shove it in the port. This reduces manifold heating. Then and only then can you block off the coolant ports in the housings with some 20mm frost/freeze plugs. Otherwise if you block off the coolant ports before the ACV port, you got a superheated manifold from exhaust heat.

That's not exactly what you were asking about, but I see you have an ACV blockoff plate already, so might as well get better performance by keeping the manifold cool.

CobraStngSVT

The idle issue sounds an awful lot to me like vacuum. Is the idle stable at 2300 or bounce around?

and +1 on the previous comment.

NCross

iTrader: (18)

Route your vac advance to the port 2nd from the front of the car when mounted. Some ports will screw up your trailing timing. Did you install new tb/spacer gaskets?

chris_g

iTrader: (29)

@Jeff - I ordered that from Atkins a while back and never realized. Thanks. I ordered another one Monday so I hope they sent the correct one this time. Will that cause an issue with the idle then? I did notice the leak and thought it was coming from my header. Guess I was wrong there!

Also, if the new gasket covers the ACV port, will it be fine to leave the o-rings in there and just button it all up? Is there a significant advantage to blocking it off? Im torn if I want to block it with quicksteel or not.

@Cobra - When playing with the idle screw and air/fuel adjustments I could get it to idle at the lowest 2300. It seemed pretty consistent, but I have heard far better. My widebody idles smoother, which is leading me to vacuum leak again.

@NCross - I originally had it on the second from the front and was suggested try the back to see if it changes. It didn't seem to. Also, I read somewhere on here that it was not recommended to put a new gasket on the black spacer as the spacer is the actual gasket. If I am wrong, wheres the best place to find a gasket for it?

Per MazdaTrix: "The stock carburator does NOT have replaceable paper gaskets; they are permanently bonded to the plastic spacer and are basically infinitely re-useable. The only way to replace the gasket(s) is to buy the new spacer."

NCross

iTrader: (18)

A rebuild kit may have them. Couldn't hurt to have them I guess.
They came with my sterling second hand. What is your jetting? That will cause idle issues.

chris_g

iTrader: (29)

@Jeff - I noticed you posted this on my other thread and I didn't even realize it:

Do you think I can swap my stock nikki metering block for the sterling block or does he modify them? If so, Ill go ahead and swap that out, too.

@NCross - Ill be ordering up a rebuild from Advance tomorrow. Thanks for the input!

Jeff20B

iTrader: (13)

For the o-rings, reuse or get new if yours are looking old/flat. Even if you install freeze plugs, it's a good idea to use or-ings because there is sometimes a slight leak as these are old housings and you're installing them by hand. Easy to get them slightly crooked. I like to add a small amount of RTV inside the hole and make sure it's clean aluminum.

For the gasket question, the gasket is so narrow in places it can leak a little if the manifold isn't totally flat/true. I've had a few manifolds that needed help, usually caused by an idiot mechanic who used one of those air die grinder driven scuff pads. It's soft cast aluminum! The old gasket can't be that much smarter than you! (gotta be smarter than what you're working with) I like to use a razor blade and spend time carefully removing the old gasket material. Works every time.

chris_g

iTrader: (29)

Can the metering blocks be interchanged?

Actually, I think I have an older (79-81) sterling on a 82-85 intake.

The old carb I have for parts is off of the 84 Im working on, so I assume they cant be interchanged. Hmmmm.

CobraStngSVT

I think your on the right track. Use some brake clean spray while the engine is idling to test the areas you suspect. Might narrow down your search before you drive yourself too crazy running around looking for parts.

j9fd3s

iTrader: (3)

yes. i had to change metering blocks when i did a sterling for a friend of mine, for some reason it just didn't work, it looked like it was installed right, passages were clear etc etc, it just would not meter fuel on the idle circuit.

i should say that sterling did a few things to the metering block, so while a stock one seems to be the same from 81-85, a sterling will have the bigger venturi's which you need to press out, and all the jets. i was lucky enough to have another dud sterling to take parts from.

chris_g

iTrader: (29)

Quick update:

My gaskets and O-Rings came in a few weeks ago and I just got time ot work on it again.

I replaced these items:
Intake Gasket
O-Rings
Plugs
Cap
Rotor

I reinstalled the distributor just to double check.

I have it idling at 1800 right now with GREAT throttle response, slightly advanced, no fouled plugs, no exhaust leak at the intake anymore. It hasnt sounded that good in a while.

But, the idle will not go any lower. It also dies after about 5 minutes of idling at 1800 or so. The fuel pressure is at 3.5psi.

Could is possible be that my idle circuit is clogged somewhere? Maybe with one of the bleeds?

Also, I found out its a 79-80 sterling that I put on a 84 intake. This should not be a problem, should it?

Thanks all!

Kentetsu

While idling, look down the barrels and see if you have fuel running into the bowls.

I'm also concerned about the glowing header, as this is usually either timing related or a lean condition. Make sure that the leading plug is firing when it is supposed to, and the trailing as well. Sometimes they can get switched around...




.

ih8dsm

Check your ignitors for the glowing header

chris_g

iTrader: (29)

Oops, I thought I put in the update that the header is no longer glowing. We had it running on/off for about 25 minutes and it didnt glow where as last time it started to glow within about 3 minutes.

82FanTC

iTrader: (9)

I could be wrong but I'm inclined to say yes. The intake for the 79-80 carb has passages cut between the primary and secondary runners on both sides and the newer ones do not. I believe the older style carbs were tuned to run on that specific intake.

However sterling may modify the carb in such a way that it would no longer matter, I do not know.

Kentetsu

In a fairly recent post, Sterling mentioned that he had an issue with some of his earlier carbs. He discovered the hard way that some of the bodies (?) don't match up with the air horns (?) of later year carbs. The only correction was to match them correctly, if I recall correctly. FYI.




.

chris_g

iTrader: (29)

So in other words, I need an early intake manifold AND a spare early carb to swap parts around? This sounds awesome.

Who wants to buy it? Purchased for $350, will sell for $225. lol

chris_g

iTrader: (29)

Update as it was nice out the past few days:

I narrowed things down enough to where it must be the carb. So, I went to my (extremely nice, but no paperwork) parts car and decided it was time to tear off the nikki and strip it (within reason).

I stripped it last night (removing basic components that are unneeded such as the TPS, Dashpot, etc), put it on today and it fired right up. It actually idled at 100rpms for a little while.

Im going to go through sterlings website and re-tune the new (parts car) nikki and I think it may finally hit the road this summer!

7aull

iTrader: (2)

nice to hear you might have this beat Chris - thanks for following up. Still have a brand-new (!) 83-ish Nikki that got Sterling-ized and haven't gotten around to installing it so helps to see what you are doing. FWIW I know towards the end there Sterling was ONLY modding the 81+ carbs for all applications. He would NOT mode the SA 79-80 carb. BUT: he was starting to mod the 79-80 intake mani, which I also have! So he seemed to think the 81+carb with early mani was the best combo, at least once he'd ported/modded the mani.

Stu Aull
80GS
Alaska

chris_g

iTrader: (29)

Yeah, the later carbs in general are much nicer IMO.

I got it tuned in last night. Idle at 750, no stutters anymore, no glowing cat, nothing. Im stoked. Its been 3 years this summer since it has been on the road!

If anyone wants a Sterling, I will let it go for well under I paid for it to recoop my cost. Or trade for a 84/85 sunroof.

cshaw07

iTrader: (14)

this is discouraging!

i have an 85 gsl with rb exhaust and sterling carb bought new in 8/3/09. I cant get mine to idle lower than 1400rpm at all. I changed all my gaskets and have checked for leaks a million times. Timing is spot on too and all my ignition components are tested and work. Im going to try pulling the carby apart and cleaning it super good.

Im glad you fixed your car, sucks about the news on the sterling though :/

clubber

I need carb and I'll shoot you a PM for it. Then I finally get a carb WooHoo!!

Spyride

What part of the throttle assembly, just part of the brackets or did the rod get bent? if so, it didnt bend up into the carb did it? I understand the carbs no longer being used, however, if you do try it again. maybe spray it with some starter fluid and see if you get a change in your idle. Just thought I'd throw that out there, since it was the first thing that caught my attention in your post.

chris_g

iTrader: (29)

It was just the throttle bracket. Everything has been straightened out.

No idea. I gave up. I want to drive the car soon.