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Setting up an engine

I'm sure I've seen this somewhere but don't know where!
I have set the tappets, plugs and points on an engine that was recently rebuilt and it runs but... Is there a procedure to follow to ensure that the setup of the distributor and carburettor are as good as they can be.
My engine is fitted with a DJ4 distributor and an FZB carb which are both in fairly good condition.
Any advice gratefully received.
Brian

Location: Near M1 Motorway Jtn 28

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Re: Setting up an engine

With the ignition advance/retard lever in full advance I set the ignition timing at 1.75" before top dead centre on the flywheel and run with the advance/retard lever between 9 and 10 o'clock. To save removing the flywheel cover and starter I have a pointer by the fan pulley and a white paint mark on the pulley. I start with the slow running adjustment on the 22FZB one turn open, fire up the motor and go for a run round the block and when the engine is hot I adjust the idle speed and mixture to get a nice even slow idle with good pick up.

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Re: Setting up an engine

Many thanks Dave.
Brian

Location: Near M1 Motorway Jtn 28

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Re: Setting up an engine

Brian, I was always taught that the valve timing and tappets should be done first then when correct check and adjust points and plug gaps followed by ignition timing then finaly carb adjustments.

Yours John Mason

Location: Mansfield Nottinghamshire

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Re: Setting up an engine

Hello John and thanks for replying.
I agree with your sequence of checking and that is what I've done but it's the carb adjustments I've been having problem with as there are adjustments available at the hand throttle, the connection to the rod that runs across the bulkhead, the rod that operates the butterfly valve, the screw stop onto the carb body and the slow running jet.
I have had the engine running but now its being difficult. I have removed some debris, including a dead fly, from the small filter in the carb body and found a partial blockage in the slow running jet.
I now have the carb off the car so that I can ensure everything is clean. The fact that the engine only ran for a second or two after two successful longer runs up the road and back pointed to a carb problem.
You must live not too far from me!
Brian

Location: Near M1 Motorway Jtn 28

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Re: Setting up an engine

I suggest you start by loosening the clamp where the accelerator pedal connects to the cross shaft so that the tickover speed is set solely by the adjusting screw on the carb. Also slacken the clamp for the hand throttle at the base of the steering column.
Set the throttle so that it runs at the slowest speed you can manage. Then adjust the slow-running mixture for fastest tickover. The throttle will then probably need to be reset and after that the mixture again. Might have to repeat this a few times.
If it is difficult to achieve a good tickover maybe the throttle spindle is worn allowing air in.
If the link from cross shaft the carb is very worn then the throttle closed position will waobble. I attached a coil tension spring alongside the rod to ensure it closed fully.
Once this is done adjust the linkage to the pedal so that it doesn't affect the tickover. Also ensure that with the pedal down to the floorboards the throttle is fully open. On my car the linkage is such that the pedal movement exactly matches the throttle at the carb, so adjustment is a bit fiddly.
Then tighten the hand throttle clamp with everything at the closed position.
I have replaced the bit of bent rod that actuates the throttle at the carb with proper ball joints. After 85 years they were very worn so there was a lot of lost movement.
My car is 1929 so is the same as yours except that I've fitted a bronze 22FZ. The Mazak on my 22FZB was breaking up.

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Re: Setting up an engine

Many thanks Jim, that was exactly what I was looking for. I'll give it a go after cleaning the carb internals.
Brian

Location: Near M1 Motorway Jtn 28

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Re: Setting up an engine

Now I've cleaned out all the bits of Viton 'O' ring out of the carb and fitted new corks to the petrol tap (see post on Fuel Tap), I'm ready to start again. I'll let you know the results.
Brian

Location: Near M1 Motorway Jtn 28

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