Edelbrock 1406 whistling

-
Ghostsoldier

Ghostsoldier

Well-Known Member
Joined
Nov 3, 2009
Messages
72
Reaction score
0
Guys,
My son's '74 Duster 318 has a brand-new Performer intake and 1406 electric choke 600 cfm carb (about a year old), which until today, was running great. When I started the car to go to work this morning, the engine took off like a bat out of hell, over-revving and rattling the valves and scaring the hell out of me.

In my panic, I kicked the gas pedal, and the idle dropped back down to normal...but after doing so, I began to hear a high-pitched whistling from the carb, and the idle became rough (like a plug misfiring).

Thinking it was a vacuum leak, I sprayed some carb cleaner around the base, and it had no effect on the driver's side. When I got to the passenger's side of the carb with the spray, the idle smoothed out and the car ran fine for a few seconds, and then went back to running like crap. I was late for work, so I decided to buy a new base gasket this afternoon, and fix the leak problem when I got home.

Well, I did that. I went to O'Reilly's and bough a replacement base gasket; I opted for a thicker Felpro type, since I hear that these 600's are prone to heat. I put the gasket on this afternoon, cranked it up, and the damn thing is STILL whistling. :cussing: I re-sprayed the area in question, and the idle picked up, et.al....the leak is still on that side.

My question for you guys is to ask opinions on what might be causing this...I read on the web that the airhorn (top carb body, not air cleaner) gasket could be leaking, or worse yet, those shafts on the choke side. I also read that the choke itself might be causing this, though I don't know how it could. And before anyone asks, my warranty ran out a year ago. angry9:

I've attached a pic of a 1406 I snagged off the web (NOT a pic of my carb, or of a Mopar), so I could highlight the areas in question: red arrows are the shafts, green arrow is the gasket....

614674188_FGUBr-M.jpg


Thoughts?

Rob
 
Most if not all of the Carter electric chokes had a vacuum unloader piston in the choke housing. There is a small vacuum gasket between the main body and the choke housing. Check that. You may need to take the choke assembly apart. Also double check the setting on the fast idle speed, andmake sure the linkage doesn't bind up.
 
Chief,
I checked the choke o-ring, and it looks fine. I removed the whole assembly, just to make sure there were no issues...the piston inside works fine, too.
I used some putty to plug up the obvious holes, and also around the shaft I suspect, but it still whistles (see pic).

S6307616c.jpg


Then I started fiddling with the secondary linkage, and discovered that when I sprayed fluid here....

S6307616d.jpg


...and especially HERE....

S6307614a.jpg


...the idle smoothed out perfectly. I found that if twist this shaft while the engine is running, it takes off like a bat out of hell, running WFO (and scaring the hell out of me)...and, if I spray a mist of fluid across the secondaries...

S6307617b.jpg


....the idle also smooths out perfectly, also. Could it be those secondary plates are whistling?

If so, I'm wondering if there is a linkage problem down there; I can't believe that the shaft seals would just "go bad" all of a sudden. And I'm not really sure of how those cams and plates are supposed to be contacting each other in all that stuff...is there a photo or a website that can tell me how they work?

Rob
 
Almost always, 100% of the time, when there's whistling around the carburetor, it's a leak at the carburetor base where it joins the manifold. I have yet to see one that was something else. Also......do yourself a favor, ok? How about using something other than carburetor cleaner to check for leaks? You're spraying something into a running engine that says "EXTREMELY FLAMMABLE" on the label. Stop and think about that for a minute. Water in a spray bottle will find your leak just a quickly and be safe doing it.
 
Thanks for the safety tip, Stroker...it's the only thing I had on hand; I hope not to blow myself up (we country boys do some dumb things, sometimes)! :iconbigg:

They say a picture is worth a thousand words, so a video oughtta be worth a dictionary! Here's what it's doing...



And, I sprayed completely around the base gasket...the new one I installed yesterday...and it does not leak; the engine idle does not increase at any point. In the video, I'm zeroing the carb spray on the secondary shaft...you can hear the whistle, and then the idle goes up.

Thoughts?
Rob
 
It certainly seems as though the secondary shaft is leaking. How old is that carburetor?
 
Like stroker said it usually whistles from the base gasket, that carb doesn't look that old, don't see how the secondary shaft could be wore that much, my old 600 has been rebuilt 3 times and the shafts are still in good shape..
 
Ghostsoldier said:
Thanks for the safety tip, Stroker...it's the only thing I had on hand; I hope not to blow myself up (we country boys do some dumb things, sometimes)! :iconbigg:


Thoughts?
Rob
Click to expand...

Hey Rob,
Welcome to FABO.
I usually try to stay away from tech advise due to so many more here with more mechanical knowledge than me.
But you asked for thoughts and as many here know, those don't cost me nothin so I share when asked.:coffee2:
I have some experience with that carb on BOF (our old 67) had a 318 with about your same set up. So here's what I had goin on.....

I think you have proven to me you have a leak around the shaft. Just my thought after seeing vid.
YES, I too (Hoosier Hollar dwellar) use carb cleaner for leak checks, SO WHAT! Anyway....
That carb is real sensitive to cross stress or "pulling" on the linkage by not setting square or any other above average stress on shafts. It took me many trys to get all linkage adjusted to operate smoothly with no cross stress or too much retun spring tension.
I'm just sayin'!
Our eddy 600 would whistle like a turbo on a semi when heavy on the petal with all 4 open going up a hill all through second and third gears (Auto) untill it planed out and secondaries closed down.
It would give all kinds of weird symptoms of illness when not installed as recomended on instalation video on website.
I'm back country hollar bumpkin hoosier boy and would never tell someone you should or tell how to spend money.
Watch the vid at the eddy website for instalation in their tech section. Link;

http://www.edelbrock.com/automotive_new/misc/tech_center/install/tech_vids.shtml

Start with Vic's intro!
They recommend a certain MOPAR style spacer under carb with 4 directional holes in it not the spread bore and not no spacer at all. Also recommend larger diameter air cleaner after total carb rebuild.
Ours would never run properly untill we followed the install vid to the letter, then we had no problems from that carb again. That was just what happened to us though.

Disclaimer;
ONLY meant as a representation of what I was thinking at the moment (My thoughts per your request) and not meant as an expert should of comment, I am not a mechanic! I did not mean any disrespect or ill will of airing my thoughts, ie my 2 cents worth is all it's worth!

Good Luck and keep us posted.
John.:cool:
 
John @ Thanks for the reply; your 2-cents is worth a lot, especially if it helps! ;) I have to say that my return spring is a bit stiff, and the throttle cable is NOT coming in on a straight-line approach--it's at a bit of an angle, so I'm sure it pulls at the linkage. I'm wondering now, as you have said, if all this has contributed to the premature failure of the shaft seals, even if they are the secondaries (but then again, I would think those stresses would only affect the primary shaft)...either way, I'll correct those 2 issues.

Hornet and Stroker @ I agree that the carb seems to be too new for this to happen...it's only about 8 months old. But, I guess like everything else in life, sometimes you get a lemon; you can plainly see that the idle picks up when I spray that shaft. Maybe it isn't the springs, as much as it's just a sudden catastrophic failure of the shaft seals.

Now that we've isolated what seems to be the culprit, I've got 2 spare 1406's I bought off of eBay for parts, so I'm thinking I'll rob Peter to pay Paul, and use those (I'm assuming these seals are o-rings)...unless I can order them separately, which I don't think Edelbrock offers (unless you buy the whole freakin' rebuilt kit...:|)

Here's the 1477 rebuild kit....can anyone tell me if those seals are in there?

1477.jpg


I'll update as soon as I change them out....nothing ventured, nothing gained. :)

Rob
 
I've never in my life seen seals on a carburetor throttle shaft. They are always just a tight fit through the carburetor base. Now I've worked on and tuned some Edelbrocks, but I've never torn one all the way down so they might have an o ring there, I don't know. The usual fix there is to have the throttle base plate drilled out and bronze bushings installed. Before I did anything, I would check the warranty on it from where you purchased it from. It could be that it has a one year warranty. Some things do.

Also.....on the carburetor cleaner thing. I recommended water in a bottle because a friend in high school auto shop class was using carburetor cleaner to hunt down a vacuum leak. He sprayed too much in and whether the engine ignited it or some got into the distributor was unclear, but it flashed back into the engine compartment and burned him severely. I remember it well because some of our shop class had to hold him down while he was trying to peel the freshly burned skin off his face. The resulting fire also burned the entire under hood area of the car before the shop teacher and I could run get fire extinguishers and put it out. So some people may ask "SO WHAT"? There is your "SO WHAT". My thing has always been why in the world risk being hurt when water will work just as good? It just makes no sense. THAT'S WHAT.
 
C130 Chief said:
No throttle shaft seals on Edelbrock carbs.
Click to expand...

I just found that out. :!:

So, after dissecting the spare carb, and making that discovery, I went back to square one and decided to try to diagnose the new carb. I swapped the (working) 1406 off of my '62 Ford 302, put it on the 318, cranked it up, and was surprised to discover IT DOES THE SAME DAMN THING. Whistles like a mother. I sprayed this carb at the base, and I definitely got an increased idle....I sprayed it at the secondary shaft, and it didn't change at all. Sunofabitch. :banghead:

Sooooo....I've decided to take Stroker and Hornet's advice, and replace the gasket...again. It's got a new one on it, but the parts guy had an issue finding it, so I wonder now if it's the correct one (the thick Felpro version). They have a Mr. Gasket spread bore type, so I'll try that one next. I really can't believe the shaft would be leaking....it just doesn't seem logical.

I'll let you know.

Rob
 
Rob I ran into this on a car, Same symptoms, it was the intake flange barely cover the base of the carb. It sealed for a while but then started to whistle after time. The fix was a gasket that fits the intake , then a spacer or plate that fits the carb base and then a gasket that fits the carb. Make sure your gasket is sealing both.. Take a piece of paper and set it on the intake . press around all of the edges to make an exact copy of the intake flange, inside, outside and bolt holes. set this on the bottom of the carb and make sure it covers all of the carb flange. If it does not you need a steel plate or an aluminum spacer to compensate for the difference and two gaskets one on each side of the plate or spacer. also spray around the intake I have seen the intake gasket whistle . If you put a large port intake on a small port head and used the small port gaskets. The gasket must match the intake. Looks like you have a 340-360- intake and you mentioned this is a 318. this could be your problem. and just by coincidence you are giving it fuel at the shaft and compensating for a greater leak. Just thought I would mention this also because the first pic is not the same intake as the rest of the pics? If it is the intake, Another thing that most do not do when bolting a different intake on is to port align it. Take a straight edge and scribe a line directly between the ports up to the top and continue this line around the top side. this is the center of each port. You'll notice there is not much room for error. The valve cover bolt holes are in the center of the ports on the head. Set the intake on dry and see if they are close . you can slide it front it or back to get them equal . If one is off an 1/8 and the rest are center you can slide it a 1/16 and make them equal. This is why new intakes are not drilled for the end pins. When you find your best location for the intake you tap down on the ends with the pins in place they will leave a mark and this is where the pin holes will be drilled. That then makes this intake alignment specific to this motor. But remember small port intake gaskets will not permanently seal a large port intake. That is more important. The alignment is only a suggestion for person who really wants to do it once and get the most out of his modifications .
 
StrokerScamp said:
Also.....on the carburetor cleaner thing. I recommended water in a bottle because a friend in high school auto shop class was using carburetor cleaner to hunt down a vacuum leak. He sprayed too much in and whether the engine ignited it or some got into the distributor was unclear, but it flashed back into the engine compartment and burned him severely. I remember it well because some of our shop class had to hold him down while he was trying to peel the freshly burned skin off his face. The resulting fire also burned the entire under hood area of the car before the shop teacher and I could run get fire extinguishers and put it out. So some people may ask "SO WHAT"? There is your "SO WHAT". My thing has always been why in the world risk being hurt when water will work just as good? It just makes no sense. THAT'S WHAT.
Click to expand...

Again, as seen in my post above that I knew I would regret.

Disclaimer;
ONLY meant as a representation of what I was thinking at the moment (My thoughts per your request) and not meant as an expert should of comment, I am not a mechanic! I did not mean any disrespect or ill will of airing my thoughts, ie my 2 cents worth is all it's worth!

High school auto shop........Should have been closer supervision. I am sorry for the freak accident you witnessed. I meant you no ill will with thoughts I voiced.

I'm almost 50 and this has never happened to me or anyone I ever worked with on cars. I'll still do it my way being even MORE carefull in the future.

Thank You for pointing out. There is nothing more important than safety. The first step to a safe job is a safe man. Burns are a horrific injury. Again I am sorry for offending you, my comment was made so as the rest of us dumb hillbillies who do it the wrong way wouldn't feel so bad.
Again, This is why I usually don't ever answer tech questions anymore. It always leads to problems for me.

Going back to restorations, general discussions and jokes section.
Sorry for letting out my thoughts again in the tech section.
Will NEVER happen again. I slipped up, it had been almost a year ago that I did it last time.......:clock:
Peace Out!:salut:
 
Hey, Oldmanmopar, the first pic is of a SBC I snagged off the web, before I took pics of my carb for this post. :) It's not my intake or carb.

But, I think you might have hit on the issue about the intake/carb base match. I put the new Mr. Gasket gasket on the car, started it up, and it did the exact same thing. Whistle City.

EXCEPT this time, the leak was on the passenger side, under the choke, and across the front of the base plate. Absolutely NO leakage at the secondary shaft this time. Grrrrrrrr. Looks like it was a coincidence all along.

So tomorrow I'm going to order a high-quality Edelbrock gasket, and I'm thinking one of these:

adapter.jpg


This is the 1/16" spread-bore adapter plate that adapts spread-bore carbs to Edelbrock manifolds without regular mounting flange...or so the info says. It looks like it might work; it's a helluva lot wider on the sides than the standard setup. Here's what Jegs says:

Putting A Square-Flange Carb On A Dual Pattern Intake? You gotta have this if you're installing a square flange carburetor on an aftermarket intake with dual square bore/spread bore flange. Eliminates vacuum leaks common to this combination.


What do you guys think?

Rob
 
Being you have a 4150 carb base this is not what you need . If this plate you are showing is what your intake opening looks like this is your problem. Holley sells a plate for their strip dominater intake for use with a 4150 base carb this is the plate you will need and ues two gaskets one on each side. This plate you pictured will not work with your carb. Is this what your intake flange looks like can you get a pic of both base of carb and flange on intake. It would help.
 
It's all good dude. I just don't like to advise anyone to use something flammable there and was explainin why. If somebody wants to burn their face off, they have been duely warned. lol

64dart170 said:
Again, as seen in my post above that I knew I would regret.

Disclaimer;
ONLY meant as a representation of what I was thinking at the moment (My thoughts per your request) and not meant as an expert should of comment, I am not a mechanic! I did not mean any disrespect or ill will of airing my thoughts, ie my 2 cents worth is all it's worth!

High school auto shop........Should have been closer supervision. I am sorry for the freak accident you witnessed. I meant you no ill will with thoughts I voiced.

I'm almost 50 and this has never happened to me or anyone I ever worked with on cars. I'll still do it my way being even MORE carefull in the future.

Thank You for pointing out. There is nothing more important than safety. The first step to a safe job is a safe man. Burns are a horrific injury. Again I am sorry for offending you, my comment was made so as the rest of us dumb hillbillies who do it the wrong way wouldn't feel so bad.
Again, This is why I usually don't ever answer tech questions anymore. It always leads to problems for me.

Going back to restorations, general discussions and jokes section.
Sorry for letting out my thoughts again in the tech section.
Will NEVER happen again. I slipped up, it had been almost a year ago that I did it last time.......:clock:
Peace Out!:salut:
Click to expand...
 
I will look tommorow to see if I have a plate. I found a picture of a performer intake and this is your problem for sure. Go on holleys web sight and look at the carb adapters. There are two the 4bbl is what you would need that you can still buy if you were putinga spread bore on a square bore , but you are going the otherway. I think a solid square bore 4150 base spacer would also work and cheaper also not as high. Holley no longer lists the one I was talking about for the strip dominator. I have a bunch of spacers and plates in the shop I will look tommorrow and let you know. If I have whatyou need you will only pay me the cost to ship. I live in Pa. 18038. I'll take some pics and fit them to some intakes here if interested. and post them tommorrow if that wil help. Steve
 
Steve,
This is the manifold I have on the 318 (except it's non-EGR)....

ph_591.jpg


...and this is the bottom of my 1406 carb....

384504861_o.jpg


Rob
 
This may sound dumb, but what are the odds of me using a thin layer of silicone spray sealant on the mating surfaces of the gaskets?

I know it's not a permanent fix, but I really need to use the car, and it only started doing this a few days ago. This would be just until I can get the correct parts.

Will that work?

Rob
 
I wouldn't put any sealer on the gasket as the gas will eat it up. Any parts store should carry the square bore to spread bore adapter. Had the same situation when I bought a truck with a Holley stuffed on a spread bore manifold.
 
You do not need or want to use the spread bore adapter. They are made to bolt a spread bore on a stock 4 hole 4150 intake. or bolt a 4150 on a stock thermoquad intake. they are pretty thick and not nessasary in your application. Like I said I will see what I have and you may have it for shipping cost. Or just get a 4150 base spacer. 1/4 inch thick aluminum is all you need gasket on each side. or a steel 3/32 thick. It will be a square opening. or 4 holes the same size. Steve
 
Fix it right. Put a Thermoquad on it. That's what the intake is made for anyway.
 
You must log in or register to reply here.
-

Back
Top