Help. 220s stopped when shut off accelerator

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heiwaz
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Help. 220s stopped when shut off accelerator

Post by heiwaz » Wed 06 Mar, 2019 4:52 am

After more than 20 years my 220s finally start!! But now have a problem, when revs up the engine runs perfect, but when shut off the accelerator the engine stopped, I think is a problem with the zenith carbs :think: . I try to find the idle screw but I'm not sure it has got, only find a screw each carb but I think this is the air mixture screw. Anybody can help me? :pale:

The zenith carbs was refubrished completly with a repair kit.

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drew56cus
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Re: Help. 220s stopped when shut off accelerator

Post by drew56cus » Wed 06 Mar, 2019 7:35 am

Hola!
I have never had much luck with Zeniths - all I can do is point you in the direction of this manual!
http://www.jaimekop.com/CarbManual/

Bart is much smarter than I. Hopefully he can guide you.
Good luck! Drew
Drew
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Re: Help. 220s stopped when shut off accelerator

Post by John Green » Wed 06 Mar, 2019 7:42 am

heiwaz wrote:
Wed 06 Mar, 2019 4:52 am
The zenith carbs was refubrished completly with a repair kit.
Refurbishing the carburetors is only half the job. The other half is setting them up. Someone with good knowledge on them can get some of the set up done as part of the rebuild, but most don't. Follow Jamies's instructions and so long as you have them set up correctly, it will be fine.

This does of course presume that the engine has good compression and the ignition system is working correctly. Incorrect timing and poor compression can also both lead to a stalling engine.
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Re: Help. 220s stopped when shut off accelerator

Post by Bartman4800 » Wed 06 Mar, 2019 8:58 pm

Usually, the first thing to check when an engine does not want to idle, is whether you have a vacuum leak in the intake tract.

I have been had a few times, when a "friend" wanted to help and installed a gasket on the intake tract the wrong way around.
Result: Engine runs great but won't idle.

If you can get your hands on a vacuum gauge, that would be even more helpful.

If your vacuum is fine, your idle jets might be clogged. There is some good foaming carburettor cleaner out there, which helped me greatly a few times.

And Drew: thanks for the compliment!

Bart
1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
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Re: Help. 220s stopped when shut off accelerator

Post by Henry Schuman » Thu 07 Mar, 2019 12:29 am

Definitely check for air/vacuum leaks!!!

The idle air /fuel adjustment screws are in the bottom base plate of each carb and basic setting is run the screw all the way in (NOT TOO HARD) then back out 2 and one half full turns .
There is an Idle jet port in the top of each carb you need to insure that they are open and have no debris as something as small as a Frog Hair will impede their function . Blow some compressed air through them to clean them . Providing the Rebuild was done correctly and the Jets and Emulsion tubes were put back correctly these basic things will usually get it done .
Don't Squat With Your Spurs On !!!!

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heiwaz
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Re: Help. 220s stopped when shut off accelerator

Post by heiwaz » Thu 07 Mar, 2019 2:03 am

I did the adjustment following the jaimecok manual and the refubrished video I found in youtube https://www.youtube.com/watch?v=7-bMXv_N-Vg (I posted other thread with all 9 videos of refubrished).

When the engine run last time correctly (lot of years ago) runs perfect, so I think the timming and electric is ok (I have changed spark plugs).

I want to know if the zenith carbs has got idle screw to adjust revs (I only found the air mixture screw, but no idle rev screw)

Bartman4800 wrote:
Wed 06 Mar, 2019 8:58 pm
Usually, the first thing to check when an engine does not want to idle, is whether you have a vacuum leak in the intake tract.
I removed the gaskets between carbs and intake manifold, and later insert the same gaskets (also, removed the manifold screws to separate a little to get access to remove the carbs screws) maybe bad adjust and have a leak?

I will do it a vacuum check with a gauge. Do you know the vacuum value and method to do it correctly? I'm very grateful for your help :pray:

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Re: Help. 220s stopped when shut off accelerator

Post by Bartman4800 » Thu 07 Mar, 2019 11:29 am

1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
2006 Ford Focus "daily driver"
2002 VW Passat V6 30V Station Wagon (SOLD - This car into a money pit)
2011 Kia Sportage "Missus commuter Bus"
2002 Mitsubishi Rosa Bus (converting it to a motor home)

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heiwaz
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Re: Help. 220s stopped when shut off accelerator

Post by heiwaz » Sat 16 Mar, 2019 9:54 am

Today I connected a vacuum gauge to the intake manifold and measure between 13-15, kept a little accelerated (can't measure at idle because stopped). I recorded a video: https://youtu.be/p3wKnaF05lg

These are the symptoms:

When the engine start cold at idle (little rev) run ok and no stopped.
Once warmed, at idle stopped.
When hold the throttle little rev the engine not run very well, like backfire.



Zenith carbs are repaired with a refubrished kit and adjust according specifications, spark plugs are changed (ngk BP7ES)

It's maybe a intake leak in the manifold when disassembled to refubirshed the carbs (according to the vacuum measures)?

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Re: Help. 220s stopped when shut off accelerator

Post by Bartman4800 » Mon 18 Mar, 2019 12:14 pm

First of all, vacuum is measured at idle, not at any throttle opening. And make sure you don't take it from a port where you only measure "ported vacuum"

I think you have a few problems.
It sounds like you have a significant vacuum leak.
You said earlier you split the intake manifold in a few places.
Go back to these joints and make sure all have a good seal (add some permatex aviation gasket cement if you are not sure)
IF YOU HAVE A VACUUM LEAK YOUR ENGINE WILL NOT IDLE PROPERLY

Also, I hear valves ticking. This means they have not been checked for a while.
While ticking valves pose no immediate vacuum issues (because they have too much clearance), too narrow clearance can do that.

So make sure all your valve clearances are set correct. From memory 0.1 on the intake and 0.2 on the exhaust. Cold engine.
Make sure you measure between top of the valve and the rocker arm, not between cam and rocker.

Once that is done, it should run a lot better.

Oh, and BP7 is too cold a spark plug for that engine. They will foul up!
Standard is BP6, but BP5 is used too.
A warmer plug will burn clean more easily.

Bart
Last edited by Bartman4800 on Tue 19 Mar, 2019 10:42 am, edited 1 time in total.
1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
2006 Ford Focus "daily driver"
2002 VW Passat V6 30V Station Wagon (SOLD - This car into a money pit)
2011 Kia Sportage "Missus commuter Bus"
2002 Mitsubishi Rosa Bus (converting it to a motor home)

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heiwaz
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Re: Help. 220s stopped when shut off accelerator

Post by heiwaz » Tue 19 Mar, 2019 2:01 am

Bartman4800 wrote:
Mon 18 Mar, 2019 12:14 pm
First of all, vacuum is measured at idle, not at any throttle opening. And make sure you don't take it from a port where you only measure "ported vacuum"
I can't measure at idle because at idle engine stopped :Doh: Only could measure at idle at cold start, because engine is a bit accelerated and don't stopped.
I take the measure from the brake assitance hose in manifold, disconnect this tube and connect the vacuum gauge.


I think you have a few problems.
It sounds like you have a significant vacuum leak.
You said earlier you split the intake manifold in a few places.
Go back to these joints and make sure all have a good seal (add some permatex aviation gasket cement if you are not sure)
I bought the intake/exhaust gasket to replace. Also will add gasket paste between manifold and carbs.

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Re: Help. 220s stopped when shut off accelerator

Post by John Green » Thu 21 Mar, 2019 5:42 pm

heiwaz wrote:
Tue 19 Mar, 2019 2:01 am
Bartman4800 wrote:
Mon 18 Mar, 2019 12:14 pm
First of all, vacuum is measured at idle, not at any throttle opening. And make sure you don't take it from a port where you only measure "ported vacuum"
I can't measure at idle because at idle engine stopped :Doh: Only could measure at idle at cold start, because engine is a bit accelerated and don't stopped.
I take the measure from the brake assitance hose in manifold, disconnect this tube and connect the vacuum gauge.
As hard as it may seam you need to take the vacuum reading from the line that goes to the distributor. The line that goes to the brake booster is at one end of the manifold and can give a false reading.

One menthod of finding a vacuum leak it to get some "start ya bastard" and spray it on the manifold to head gasket with the engine running, even at high revs. It there is a leak it will get sucked in and upset the engine. At a guess this is called something else in Spain....

https://www.nulon.com.au/products/aeros ... ne-starter
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Re: Help. 220s stopped when shut off accelerator

Post by Bartman4800 » Thu 21 Mar, 2019 7:34 pm

empieza ya bastardo :dance: :laughing6: :laughing6:
1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
2006 Ford Focus "daily driver"
2002 VW Passat V6 30V Station Wagon (SOLD - This car into a money pit)
2011 Kia Sportage "Missus commuter Bus"
2002 Mitsubishi Rosa Bus (converting it to a motor home)

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Bartman4800
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Re: Help. 220s stopped when shut off accelerator

Post by Bartman4800 » Fri 22 Mar, 2019 10:54 am

John,

On my finnie with Solex PAITA's, the line going to the dizzy is definitely ported vacuum.
If that is the same on the Zenith version, you would not measure any vacuum at idle.

Can you confirm?

Regards, Bart
1963 220 Sb Sedan "Kermit" (Australian Assembly)
1960 220 Sb Sedan "Zum Schlachten" (Early German Assembly, with a torsion bar spring for the bonnet) - Stored in Country WA
1981 Subaru Brumby 1.8 with Weber and 5-speed box "little utie" - Sold to another enthusiast!
2006 Ford Focus "daily driver"
2002 VW Passat V6 30V Station Wagon (SOLD - This car into a money pit)
2011 Kia Sportage "Missus commuter Bus"
2002 Mitsubishi Rosa Bus (converting it to a motor home)

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