223 Low Vacuum

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Steves55
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223 Low Vacuum

Post #1 by Steves55 » Mon Mar 12, 2018 1:51 pm

My 223 has been running terrible (stalling when coming to a stop with difficulty re-starting) and bad gas mileage. Vaccum is holding a very low steady reading of 8 during idle. I have tried locating possible leaks with brake cleaner spray around the intake manifold and carb mount and throttle linkage with no change in RPMs. I don't think it is carb related so I will be asking a pro mechanic to do a compression check and also check the valve lash and timing. Anything else I should look for? Thanks. Steve

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bubba22349
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Re: 223 Low Vacuum

Post #2 by bubba22349 » Mon Mar 12, 2018 4:34 pm

How is the condition of plugs, wires, cap, and rotor?

In this order with engine warmed up good.
1. For sure first reset the valve lash.
2. Then check the point dwell.
3. Set base timing 2 to 4 degrees more than stock depending on your local area alt. and weather.
4. Set carb mixture to lean best idle.
5. Set curb idle to 475 to 500 RPM (on some engines I have even set them to idle as low as 375 to 400 RPM) if manual trans, add 50 to 100 for auto trans.

Let us know how it does. Good luck :thumbup: :nod: edited
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

Steves55
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Re: 223 Low Vacuum

Post #3 by Steves55 » Mon Mar 12, 2018 5:20 pm

Thank you very much. I see the intial timing is 5d BTDC so you are recommending 7 or 8. I will let you know how things go. Best, Steve.

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B RON CO
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Re: 223 Low Vacuum

Post #4 by B RON CO » Mon Mar 12, 2018 6:42 pm

Hi 8 inches of vacuum is not good. If it was caused by a sticky valve the vacuum would fluctuate. Check the vacuum diaphram in the distributor and maybe the vacuum wipers for a vacuum leak. You can buy a compression tester for $30 at Napa. Good luck
B RON CO. Still workin' on it!

1933 Ford Pickup - 59A Flathead V8
1966 Ford Bronco - U14 - 170/200 Straight 6
1966 Ford Mustang - 289 V8

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bubba22349
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Re: 223 Low Vacuum

Post #5 by bubba22349 » Tue Mar 13, 2018 12:34 pm

Steves55 wrote:Thank you very much. I see the intial timing is 5d BTDC so you are recommending 7 or 8. I will let you know how things go. Best, Steve.



You didn't state in your post what your working on but these are the Stock tune up specs for a 1955 223 car a truck maybe slightly different on base timing and usally a little higher curb idle RPM.

1. Valve lash is set to .019 Hot. This is at the normal operating temperature. Valve lash is quite important to a 223 engine performing or running good and its economy, over time these lash settings have a tendency to change. This is also why it's the first tune up setting I make on them.
2. Spark Plugs are gapped at .035
3. Point gap is set at .024 to .026 for the base generic setting you would want a end up with Dwell setting of 36 Degrees for best results.
4. Base timing is set to 3 degrees BTDC. So your currently already at 2 degrees more than stock, but yes you can try 7 or 8 degrees and see how it does.
5. With the engine warmed up and the choke fully open. Set idle mixture to lean best idle. This done by setting to the highest Idle RPM and then only turning the mixture screw in a 1/4 turn (leaner).
6. Last set the Curb idle to 475 RPM for manual trans, 450 RPM for auto trans in drive with parking brake set, this will usually be 50 to 100 RPM higher when trans is in Neutral or Park.

The order of the settings can make a differance to the final tune this is why the carb settings are last thing. Are you confident that your carb is in good condition and with the float level is set correctly? Good luck :thumbup: :nod:
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

Steves55
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Re: 223 Low Vacuum

Post #6 by Steves55 » Sat Apr 07, 2018 4:14 pm

Problem resolved. I took the truck to a highly recommended mechanic. The valve lash was way out of adjustment as well as the timing was too advanced. Once the proper valve adjustments and timing was set, the engine absolutley runs remarkable. When I bought the truck 8 years ago, the previous owner was adding lead additive after each fill-up. I never followed through with doing that and wondering if this possibly contributed to the valve problem? I am thinking about using additive but have mixed feelings. Is it necessary? Thanks.

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bubba22349
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Re: 223 Low Vacuum

Post #7 by bubba22349 » Sat Apr 07, 2018 8:25 pm

The pre 1980 fuels still had lead that protected the valve seats and guides, without the lead the seats and guides wear faster. So yes this could be part of the reason the valve adjustment was off by so much. Good luck :thumbup: :nod:
A bad day Drag Racing is still better than a good day at work!

I am still hunting for a project car to build but with my current low budget it's not looking so good. My Ex- Fleet of Sixes these are all long gone! :bang: 1954 Customline 223 3 speed with O/D, 1963 Fairlane project drag car with BB6, 1977 Maverick 250 with C4, 1994 F-150 a 300 with 5 speed.

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Daves55Courier
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Re: 223 Low Vacuum

Post #8 by Daves55Courier » Mon Apr 16, 2018 10:58 pm

So then, it has been many decades since the head was rebuilt, thus the valve seats have never been changed. They need to be changed to flame hardened valve seats. After that, the lead fuel additive will not be necessary.

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