Holley 5212

[Buzo]

The car & stock carb did run great, during the cold weather.
Its getting warmer here and started to have issues.

1.-Idle boost was on and off intermittently. I had to unscrew it to avoid the engine to accelerate and de-accelerate like crazy. But then I had to adjust the Idle rpms around 1200 to be able to keep around 900 when in shift.

2.-Strong fuel odor when the windows are open. Can't see wet anywhere, so it may be fuel vapor somewhere.

3.-at 2000 rpms and 40 mph the car is like... how to say it in English? pulling? We say "jalonear" in spanish.

4.-Have never reached stable rpms below 900. I think 900 is too high. I would like 800 for better fuel economy.

5.-Constantly shaking at Idle.

So what?

I partially took appart all the hoses and installed a Holley 5212 I found in the local JY (after a quick rebuild).

There is less shaking, but the Idle rpms are constantly changing from 900 to 1000. like 1 second at 900 and 1 second at 1000 and back to 900.

So far, that's the only concern I have with this carb, Oh yeah I recall the second problem, the engine shuts off everytime I turn to the right

This is my second day testing, so still lot to adjust, but any advise will be greatly aprecciated.

[Oldblueaccord]

I think the word you are wanting is "surging". It is when a carb feels like it is accelerating and decelerating on its own at the same MPH (speed).

As far as the idle it seem you might have a vacuum leak.

800 rpm idle even with my car being fuel injection is hard on a 4 cylinder motor there not a well balanced as say an American V-8 is.


wp

[2oodoor]

what kind of car did that carb come off of?
you may need to either raise or lower the float level, depending on the cause of the right turn stall, surging usually means too low float level so maybe that is the clue...
also, the holley will have the linkage on the left side not the right like oem if Im not mistaken, and depending on the model you have it may need a baffle in the bowl to prevent gas sloshing for front wheel drive applications.

[Oldblueaccord]

The car & stock carb did run great, during the cold weather.
Its getting warmer here and started to have issues.

1.-Idle boost was on and off intermittently. I had to unscrew it to avoid the engine to accelerate and de-accelerate like crazy. But then I had to adjust the Idle rpms around 1200 to be able to keep around 900 when in shift.

2.-Strong fuel odor when the windows are open. Can't see wet anywhere, so it may be fuel vapor somewhere.

3.-at 2000 rpms and 40 mph the car is like... how to say it in English? pulling? We say "jalonear" in spanish.

4.-Have never reached stable rpms below 900. I think 900 is too high. I would like 800 for better fuel economy.

5.-Constantly shaking at Idle.

So what?

I partially took appart all the hoses and installed a Holley 5212 I found in the local JY (after a quick rebuild).

There is less shaking, but the Idle rpms are constantly changing from 900 to 1000. like 1 second at 900 and 1 second at 1000 and back to 900.

So far, that's the only concern I have with this carb, Oh yeah I recall the second problem, the engine shuts off everytime I turn to the right

This is my second day testing, so still lot to adjust, but any advise will be greatly aprecciated.

Ok at 2000 rpms mine surges also. I think its the 2 vacuum advances right at that RPM fluctuates. I can hold my car at 2200 - 55mph and it will surge and buck all day.


wp

[Buzo]

Ok at 2000 rpms mine surges also. I think its the 2 vacuum advances right at that RPM fluctuates. I can hold my car at 2200 - 55mph and it will surge and buck all day.


wp

Now that you said that, I vacuum tested the advance actuators and found the main one not holding vacuum. Do I need to replace the whole distributor? I don't think right?, so I need to investigate if the actuators are sold alone locally.
However, the car does not surge with the "new" carb which does not support the theory of the advance as the cause.

[Buzo]

what kind of car did that carb come off of?
you may need to either raise or lower the float level, depending on the cause of the right turn stall, surging usually means too low float level so maybe that is the clue...
also, the holley will have the linkage on the left side not the right like oem if Im not mistaken, and depending on the model you have it may need a baffle in the bowl to prevent gas sloshing for front wheel drive applications.

The holley carb was already removed from the original car, I only know it says "motorcraft" in the electric choke.
This holley also have the accelerator linkage in the same side than the OEM, so I had no problems adapting it. The ATV is comming straight from the pedal, so that was one less thing to worry about.

I supposed the cause of the engine shutting off was fuel slosh, since the jets are in the right side and the fuel sloshes to the left in a right turn. I am thinking also there is too much flow restriction in the fuel inlet (I blew through the inlet when adjusting the float and needed too much effort). The floats are at a couple of mm before touching the top carb cover. So no more adjust is possible.

Maybe my pump is not pumping enough flow/time through that orifice.

How that "baffle in the bowl" looks like?

[Buzo]

I think the word you are wanting is "surging". It is when a carb feels like it is accelerating and decelerating on its own at the same MPH (speed).

As far as the idle it seem you might have a vacuum leak.

800 rpm idle even with my car being fuel injection is hard on a 4 cylinder motor there not a well balanced as say an American V-8 is.


wp

I feel beter now, I thought I could get below 900. So I can stop worrying about the high rpms.

I'll keep checking for vacuum leaks, since i removed the metal tubes from the engine, it was easy to close all the maniful ports, however, the home made carb adapter or the carb itself can have a leak.

Something that I noticed was the mixture adj screw has no effect in the rpms, I adjust it all the way in and the engine does not stall.

[Buzo]

Just in case I need to go back to the stock...


I need to be at this height. Right now I am like 1 in above, with no filter!


Adapting the linkage from an old stock carb. Cut all the bends off to make it flat


The two parts matched.


WOT just to make sure.

[Buzo]

And if you though i was done with my OBDZ project, I am not! This is how the O2 sensor reacts now that it is open loop.

It goes below 0.5 only when I take the foot off from the pedal. It stays rich even at Idle. What does it mean in terms of fuel economy? We'll see at the end of the week.

[Demon1024]

Did adjusting the float fix the stalling issue? I've had bad coils do the same to me. Only it was left turns.

900 rpms isn't that bad man. My stick idles at 1k and the auto is at like 1100. After you've got all the bugs outta the rest of it just make sure to set the idle where it'll run smooth

[Dr_Snooz]

^^^ x2. I don't know why Honda maintains the fiction that any of their cars will idle properly at the recommended 750 rpm. I've never had one that would. They all did best at >=1,000 rpm.

[Xaisk]

Yeah our stock 89 idles pretty solid at about 800, but when you turn the A/C comp it starts to shiver. Im running a weber on my 88 hatch and it can get down to 750 or lower perhaps without having any problems. The only problem with mine is that I need new motor mounts and thats why mine vibrates so much. It always vibrates =(

[2ndGenGuy]

I feel beter now, I thought I could get below 900. So I can stop worrying about the high rpms.

I'll keep checking for vacuum leaks, since i removed the metal tubes from the engine, it was easy to close all the maniful ports, however, the home made carb adapter or the carb itself can have a leak.

Something that I noticed was the mixture adj screw has no effect in the rpms, I adjust it all the way in and the engine does not stall.

Mixture screw having no effect is a symptom of the jetting being off. When you have the idle jetting correct, the idle screw will be very sensitive.

Another thing I have noticed about the 5200 series carbs is that the throttle shafts wear out and cause a nasty vacuum leak. I had two of them that I got from two totally different sources and they were both like that. Supposedly there is a way to rebush the shafts so they don't leak, but I never figured that out... I imagine it involves reaming and press fitting some brass bits in there... but that would be a good thing to check... It was absolutely a terrible idea to have no replaceable bushings on the throttle shafts when the carburetor is an aluminum body. Explains a lot about the state of the cars that ran these carburetors from the factory.

Also, my 5200s didn't have idle jets that were removable, they were cast into the carburetor, which means you're stuck with that idle mixture. Not sure if yours is the same way or not...

[2oodoor]

precisely^^^^
also if the mix screw was ever bottomed out to the point it was damaged, even the slightest burr or bend ruins them. A vaccuum leak would also cause a no effect condition and finally, there is a solenoid that screws in some of those carbs, in the main body.

what is that cap thing in the second picture, also the aluminum cover that has an allen head adjustment, not sure I remember what that does ? In the third pic the base plate looked warped just an illusion hopefully.

[Buzo]

Thanks everyone for your comments.

I started checking for vacuum leaks in the adapter plate and throttle bushings by applying some carb cleaner, couldn't hear the engine rpms changing. I am pretty sure those are the only possible sources of leaks since everything else has been blocked off.

what is that cap thing in the second picture, also the aluminum cover that has an allen head adjustment, not sure I remember what that does ? In the third pic the base plate looked warped just an illusion hopefully.

The thing with the allen is the choke vacuum kick adjustment screw. It is to adjust the gap when the choke is fully closed.
Your appreciation is right, I overheated that side of the carb when soldering the adapter plate screws. I will post pics later of my franky base plate.

Did adjusting the float fix the stalling issue? I've had bad coils do the same to me. Only it was left turns.

No it didn't, the floats are at the maximum fuel capacity, so when approaching a 90 degrees right turn & braking, I need to use two feet to avoid it to die. The problem doesn't show up if turning right and accelerating.

^^^ x2. I don't know why Honda maintains the fiction that any of their cars will idle properly at the recommended 750 rpm. I've never had one that would. They all did best at >=1,000 rpm.

900 rpms isn't that bad man. My stick idles at 1k and the auto is at like 1100. After you've got all the bugs outta the rest of it just make sure to set the idle where it'll run smooth

I am OK with 900 now. With the stock I used to start the day at 900 and end up with 1200. At least I have 900 constant now.

Mixture screw having no effect is a symptom of the jetting being off. When you have the idle jetting correct, the idle screw will be very sensitive.

At least I know the direction to go in the jetting change, and those jets are interchangeable. Something that I like about this holley is that the knocking noise i used to have with the stock has completely disappeared! So I am OK with the secondary jetting behavior.

[Buzo]

there is a solenoid that screws in some of those carbs, in the main body.

Actually there is a solenoid in one of the corners of the top cover with a 3/8 vapor outlet tube, I am pretty sure it is to avoid the vapors to escape (or go inside the intake maniful) when the engine is off, so it is normally closed when the engine is off, open when on, at least that was the way the stock was, but using vacuum instead of a solenoid. Currently it is disconnected, I think I will just connect it in parallel to the choke signal.

[2ndGenGuy]

At least I know the direction to go in the jetting change, and those jets are interchangeable. Something that I like about this holley is that the knocking noise i used to have with the stock has completely disappeared! So I am OK with the secondary jetting behavior.

There usually are the interchangeable jets inside the float bowl, the mains... But are you sure the idle jets are? They are on the sides of the carburetor, covered with a brass cap that you can unscrew... I'm not trying to be a know-it-all if you already know this... but I didn't realize it for a long time when I first started messing with carbs is all... I'm sure there are 5200s out there with swappable idle jets.

[2oodoor]

Actually there is a solenoid in one of the corners of the top cover with a 3/8 vapor outlet tube, I am pretty sure it is to avoid the vapors to escape (or go inside the intake maniful) when the engine is off, so it is normally closed when the engine is off, open when on, at least that was the way the stock was, but using vacuum instead of a solenoid. Currently it is disconnected, I think I will just connect it in parallel to the choke signal.

yes that sounds like a bowl vent solenoid, you wont need that unless your using emissions cansister.
The idle jets are a little different than most webers, if you indeed have those that are swappable. Brass screw caps on either side of the carb body milddle ways.
Ive seen vaccuum advance create vaccuum leaks if you have vaccuum attached. Use only the one with that carb not both. /the diaphragm can leak internaly.

YOu do good work!

[Buzo]

Ive seen vaccuum advance create vaccuum leaks if you have vaccuum attached. Use only the one with that carb not both. /the diaphragm can leak internaly.

YOu do good work!

thanks! I already confirmed i have a vacuum leak in the distributor's main advance actuator. I need to find how to fix it. The car needs a long crank every morning so i am sure i need to adjust the timing. I just have had no time this week.

[Buzo]

There usually are the interchangeable jets inside the float bowl, the mains... But are you sure the idle jets are? They are on the sides of the carburetor, covered with a brass cap that you can unscrew... I'm not trying to be a know-it-all if you already know this... but I didn't realize it for a long time when I first started messing with carbs is all... I'm sure there are 5200s out there with swappable idle jets.

I'm affraid i am going to need some pics of these idle jets. The ones i am referring to are in the bottom of the bowl, marked as primary and secondary in the chilton's manual. But as far as i can understand you, there are other idle jets besides the ones in the bowl?

[2oodoor]

I dont have time to figure how to host a diagram but here...
http://www.carburetorfactory.com/expvw17.html

Now, look at #47-48 and 49-50, those are idle jets and retainer. Be very careful not to scratch or damage them when you clean.

[2ndGenGuy]

Yeah, the ones inside the bowl are the main jets. They do have some effect on the idle, but not like the idle jets.



This is probably not your EXACT carburetor, but it's close enough. 33 and 33a are the idle jets. I think this diagram is wrong, because it makes it look like 33 goes into the Accelerator pump diaphragm, but really, if you drew a straight line, it would go into the side of the barrel...

Actually, here's a photo:

[Buzo]

This weekend looks like is gonna be another one under the hood.
The goal will be to remove the EFE heater, maybe rework the adapter plate to make room for the air filter, and play with the idle jets.
I believe I will rework the stock air filter to fit the new carb because I want the hot air intake function, and most important, i don't have money to get a new one. The new carb demonstrates that is more powerful than the stock one and the fuel economy didn't change. So ready to make non-return changes to the car!
Thanks a lot for your recommendations and for the exploded views and pics.

[2oodoor]

you can maybe get the base of an air cleaner off a dodge K car, omni, shoot a bunch of American cars in the 80 used some form of those carbs, or something else that used that carb and go from there.
Also I ordered from a toyota off road outfitters website to get a real weber cleaner brand new for less than 20 dollars shipped.

[Dr_Snooz]

The new carb demonstrates that is more powerful than the stock one and the fuel economy didn't change. So ready to make non-return changes to the car!

Bye, bye OBDZ.