mslisaj

I have two cars with 440's and Six Packs. When they run they run flawlessly and I have been very lucky for many years. The biggest issue is after sitting for awhile and a hard start with a backfire I always lose a power valve.
Well I have lived a charmed life with both of these set ups as I have been very careful with starting and haven't had a problem. But today, after a two year sit I had big issues. I had two problems actually with the center carburetor. One, I had a backfire and I know I knocked out the power valve. But also for some reason the carb was also flooding out the vent with a float/needle and seat issue. Well looking in my records It's been 20 years and 110 miles since I put the last power valve in. So I buy these valves ahead of time and keep them in stock so I propose putting back a Holly 125-55 power valve.

Also a couple of years ago I was looking in a Summit catalog and found the "Power Valve Check Ball" installation kit # 125-500 and have one of those to put in this time. Also I believe I have gotten away with these carbs sitting so long as I use Holley's treated paper gaskets instead of the old cork. So here are my questions:

1) Can you tell me what the opening vacuum is for that number power valve I am going to put back in. The only marking on the old valve is E H 6. But This is the valve I use on the other six pack so I think I figured this out with trial and error.

2) Any thoughts on the install of that "Power Valve Check Ball" kit? It seems very straight forward and it comes with the drill and stop.

3) Also I know that the metering body gaskets for these are special and any suggestions there where I should get a pack or set.

4) Being I have to take this center carb all down I was just going to buy a rebuild kit for that carb number. Any thoughts or warnings there?

Here are the numbers of my Center Carb:
List 4374 Second number 2839
Metering body number 4779 Second number 6541

These carbs are such a chore to get on our off and work on them so I really want to do this right the first time. It's been awhile since I have been in them so I am open to suggestions and recommendations.

Thanks for your help and guidance.

Lisa

RacerHog

5.5 Inches of vacuum for the valve...
STD. Overhaul kit should do the trick...
Careful of those old valves you have laying around. The Rubber can go bad..

mslisaj

Okay, you're not seeing a real issue to this overhaul and "back fire valve" installation. This is good new. The valves are still in the factory sealed Holley packages so I'm thinking they are okay. I try to buy ahead as I am always not sure how long parts like this would be available.

But thanks for the information and I must say "wish me luck".

Lisa

Archer

Lisa -

There are more people driving around with blown power valves than you might imagine. Most don't even know it. Just reality.

The manifold vacuum determines the size of the power valve, in a 2:1 ratio. If you are hold 11" of vacuum at idle, you want a 5.5 PV, regardless of what the "specs" are. So check your vacuum pressure first.

The flooding sound more like a float issue.

The check ball addition depends on how comfy you are taking a drill to the base of your carb. I have an older 850 DP on my Charger, and haven't added one yet. (I do have one laying around as well.)

You shouldn't have a problem getting a rebuild kit for those carbs. If you do, call Mancini Racing.

Archer

mslisaj

Thanks Archer for taking your time to reply. I have been in this business way too long and built these vehicles when I was in my late 20's/early 30's so we have been around together a long time. I'm just a lot older now and bending over the fenders isn't any fun any more. But with all that said Yes I do have the skill level to take a drill press to that carb base and do the modification. As I mentioned originally if I am very careful starting these cars after a sitting spell I can get them running without a backfire. But I look forward to this modification to prevent this in the future. And yes I need to run the cars more often and plan too now that I am retired and actually have the time now.

Thanks for the explanation of the power valve vacuum opening number. I forgot how that worked. I wish I had this engine running so I could take that reading but it's got a little bit of a cam in the engine so I believe through trial and error I discovered that the 6 to 5 inch of vacuum worked well and the cars would idle nicely.

On the blown power valve, I remember when I got my first six pack set up. I overhauled the carbs and had everything done and apparently I blew the valve right off. I worked on these carbs for weeks, even had professionals play with them and finally by accident the power valve was replaced with a lower opening vacuum number and magically the car ran perfect.

On the flooding, I removed the needle and seat and it was clean but the o-ring that seals the valve to the bowl was pretty smooth. The combination of lousy fuels and time got to it so that will be a simple fix too.

For anyone that has worked on this set up knows they are just a total PIA to work on. You have to remove the end carbs to get to the center and all the linkage and hoses, not to mention the fuel lines are just impossible. When these run they can't be beat but when you have to work on them it makes one wish for a simple AFB sitting there handling all the chores.

Thanks for the advice about Mancini. I forgot about them and the Repro parts that are available today is truly amazing.

Wish me luck.

Thanks again.

Lisa

Drag Pak

mslisaj

Actually, if you grind down an open end wrench you use to hold the fuel line bushing at the carburetor, you can get a tube wrench on the fuel line and remove the center carburetor first. I have done this many times!

Peter

mslisaj

Hi Peter,
Thanks for the idea. I have thought about it but didn't think that was possible. I certainly have the extra wrenches to sacrifice one that would make this job easier. I'll give it a try. As I have said many times before, these are awesome carburation set ups when they are working and total nightmares to fix when they're not. But the reality is I haven't had that much trouble with them when you consider the amount of time they have been on the cars and the years on them.

I so appreciate all the ideas and help you guys are giving me on this subject. Off to get the parts today and get this back working again.

Keep the idea's coming.

Lisa

Drag Pak

One further note.

The center carburetor slides out to the passenger side. When I disconnect the outboard carburetor linkage rods, I tape them to the center carburetor to ease the removal process.

You'll get the idea!

mslisaj

That's and interesting idea "Drag Pak". Hopefully I can get this right the first time but it would make life easier. I'm trying to remember, didn't I have to remove the fuel line from the back carb to get that back bold on the center carb? Yes I did. But yes these things are a bear to work on.
Parts are coming tomorrow so maybe I'll get it back together and give it another try.

Thanks again for all the suggestions.

Lisa

RacerHog

Let us know how the check valve install goes....

TVLynn

On newer Holleys the backfire valve is built in to the carb

mslisaj

Well this certainly is an older Holley. I'm thinking a 70 or later becase it's on a Chrysler, cast iron six pack manifold. Definitely old school.
I'll be sure to report as I have to set the drill stop on the drill and everything. But I have the kit and directions and I'll let you know how it goes.

Lisa

mslisaj

Okay, here is how the Check Valve Ball install went. First I followed the directions to the letter and double checked everything. In a word the install went smoothly and will work. But here are my observations of this kit and the install. The original hole for the vacuum to get to the power valve in the carb base is .155 of an inch. The drill is a #16 drill at .177". The little orifice/seat that I installed was .190" in diameter. Here is the kicker for me. All this went well but the check ball that was installed was .140" in diameter. The only thing keeping this in place and from going through the engine is a very tiny, very light wound spring. I'm sure Holley gave this some thought and I'm sure worse case scenario is that 440 could pass that ball right through it without any damage but this would be my only concern with this kit. The orifice is a .013" press fit and it's not going anywhere. But you asked for my observations on this and here they are.

Comments are always appreciated and I may start another thread with this Check Ball Kit install information and see what others have to say or what they have seen.

Regards,

Lisa

RacerHog

If it saves the power valve and doesn't leave town. Them you have done a great job and saved yourself a lot of future work..

mslisaj

I'm pretty pleased with it and it will work very well. I also discovered that this carburetor was in real need of this overhaul. It was kind of glued together from the varnish in the gas. Needless to say before I fire this up after all this work I will drain and clean the entire fuel system. This vehicle has had it's share of issues that sort of put it on blocks and one by one I am working out the kinks and it will be show quality again.

Thanks for your support and I think that ball and spring will stay exactly where I put them.

Lisa

TVLynn

Like any old car, You truly never get finished...

mslisaj

I stand back and look at my fleet of show cars and trucks and I will have plenty of work for the balance of my days. I retired last year and I will never run out of work to do. Most of all I have to drive them all more often. The sitting takes a real toll.

Lisa

RacerHog

Are you going to tend to the other 2 carbs now that you know they may need some attention also?

440roadrunner

No power valves in the outers

Wish you'd taken some photos of this. I've never "done one." In fact, I haven't run a Holley 4bbl in some 30 years or more, LOL

mslisaj

You can bet I will check over the "other two" carburetors as I have them of and in my hand. Now's the time for sure.

For "440roadrunner" I'm not sure what you would want pictures off. Here is the Holley instructions sheet for the installation of the kit and it's pictures are pretty good. The job is as simple as the instructions. If you let me know I can take a couple of pictures of the finished job before I put the carb together but we're really talking about small parts here. But let me know if you want pics.

http://www.jegs.com/installationinst...10-125-500.pdf

I personally never liked Holley carburetors over all the years I have been around this stuff. An old Carter AFB or even a Rochester Quadra-jet I felt were better and more reliable carbs. But Holley flooded the market with their "performance" carburetors and they have the name. Then I find myself with two totally complete Six Pack set ups and now I am the proud owner of SIX of a brand of carburetor I would rather not have. But as I have said here many times, when they work they work great and all six of mine perform very well. This issue that I am having and correcting now is due not to the fault of the carburetors but a lot of time and old gas.

And Gentlemen, I'm not saying Holley is a bad carburetor so don't get me wrong. My comments are due more to my training in the industry and my own personal preferences. I prefer plunger pumps to diaphragms. Vacuum pistons and metering rods to a diaphragm type power valve enrichment system and I just found the other carbs to be more rugged and trouble free. Just my opinion. Yes the Holly is infinitely more adjustable with different size needle and seats, power valves, jetting, accelerator pump sizing and much more so i can see how it lends itself to specific applications. But for simple fuel delivery I'll take the other brands that I mentioned here.

Again I appreciate the comments and the conversation and most importantly you guys sharing your help and experience. It's been awhile since I have been in these carbs so I am not as sharp as i used to be.

Thanks again,

Lisa

RacerHog

But the fuel contaminate might be an issue if it was in the center carb, EH..

440roadrunner

Oh I see you meant "rebuild in general" Thought you were referring to the PV mod

mslisaj

Okay Gentlemen, here's where we are right now. First I have to thank Drag Pak for the wrench idea. I'm here to say I can extract the center carburetor with out removing either end. Fabulous idea and now i have a wrench exactly like yours in my tool box and it works as advertised.

Then RaceHog Bob, Well partner, you warned me about new but old power valves. But I'll talk more about that later but here is the story to right now. Bottom line is I have the truck running perfectly now. Albeit NOW it needs a new fuel pump as this one is leaking pretty good out the top vent. But that is as straight forward as it gets. But here's the carb story.

Okay, brand new fuel system. Everything blow out, tank cleaned out and new "clear" premium for fuel now. It's so nice working with real gas. All new hoses filters and everything. So I fire the truck up and it's running a lot better but FAR from perfect. It's running fat - just like a blown power valve!!!! Okay Drag Pak here is where you come in. I removed the fuel lines and now magically I can get to the base bolts of the center carb. Mine slid out to the drivers side as the throttle linkage just wouldn't let it go the other way but I had it off the car in about 15 minutes. Well I take the carb all apart and all looks good. I am suspect of the Back Fire Valve that I put in but it looks and tests okay. So I give Holley a call. After a 10 minute conversation with the tech and it was clear he thought I was a fool to be fooling around with a 70's carburetor I just let him go as he had no magic bullet for me. He did tell me that the later Holley Carbs had smaller openings in the throttle body where the "check ball" goes in. Well this was all I needed to hear. I have this one the bench and NOW and I take a punch and drive the Check Ball system out of the base. I'm not going to use it. I changed something here that was not allowing this engine to idle correctly. Now I take the metering body with the power valve in it. I suck on the power valve and the valve moves in but it seems to slip back out when I hold it with my tongue. All this is suspect to me now so I take the OLD power valve and put it in the metering body and suck on this one and there is no doubt this one holds a vacuum. So I put it all back together with the OLD 6.5 power valve and NO power valve check valve system in the throttle body. Put it all back together with Drag Pak's wrench and fire it up and it runs like it left the Chrysler factory with a little more cam of course.

My observations are these, I have a tendency NOT to field engineer. Chrysler and Holley wanted that .155" passage in the throttle body for the vacuum signal to get to the power valve for some reason. So it's back open to that now with out the restriction of the check valve system. The power valve being good or bad, well who knows. If your going to change something change them one at a time. I made two changes PLUS cleaned the carburetors of all the varnish and bad fuel. I may one day put that valve back in if I'm sitting around with nothing to do. But until then It's going back in the box. I have another six pak set up on my 65 Satellite and it's running perfect now too.

So there you have it gentlemen! Thank you for all your help and suggestions. I am a better Holley mechanic today thank to you guys with your support and idea's. Now I'll put a fuel pump on it and then maybe I can take if for a drive and test the brake caliper repair that started all this. I'll keep you all in the loop if I run into any difficulties or even go back and try the check valve kit again. But for now it's running just fine.

Thank you all again for taking your time to help.

Lisa

RacerHog

Job well done...... Happy you got it running again.....