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We're almost on the road!

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77_MG_Midget

77_MG_Midget

Jedi Trainee
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well, got the engine running pretty good. Only have the interior left to do and we'll be on the road again for the first time in 14 months.

But, I do need some help.

First, I need some advice on the best way to tune the carb. It's the ZS 150 CD. Can it be done without the "special" tool the book talks about? How do I know if I'm too rich or too lean?

Second, I got a coolant leak from the heater shutoff valve. I've pulled it apart and replaced the gasket between the valve halves, but still leaking. When I had it apart, I noticed a little brass screw, I think it may be to take the insides out of the valve.

Has anyone rebuilt the heater shutoff valve? is it even possible?
 
The special tool is kind of a rip off IMHO.

All you need is a long allen key and two hands. While you make adustments to the needle height with one hand, you hold the piston in place with the other. Just stick you finger throught the front of the carb and put pressure on the piston to keep it from turning.

I don't recall the size of the allen key. If someone else does not respond before I get home tonight, I will send it to you then along with a great article on tuning ZS carbs. It discusses how to determine if you are too rich or lean.

I don't know anything about the heater valve.
 
I broke down and bought the adjusting tool; the adjuster on mine is pretty stiff anyway so holding it with one hand wasn't very practical. Here's a good article on adjusting the Zenith by ear and not with the tailpipe sniffer.
https://www.sterlingbritishmotoringsociety.org/files/zenith%20stromberg%20tech%20tips.pdf

As for the heater valve, it can be rebuilt. Mine was leaking pretty badly, and you are correct, the little screw holds the valve body in. There's an O-ring that is supposed to seal it. Mine was pretty dry and crispy when I attacked it. The hard part is finding the right size O-ring. I bought one of those universal grab bags from Autozone and found one that was close, but it took a little shaving of the edge of it to get the valve back together. Mine made a tight enough fit that I just leave it on and decline to turn it off, but it fixed the leak. I also cut new seals for the two halves out of a sheet of gasket paper.
 
Thanks everyone, that was the info I needed. Much appreciated!
 
We are waiting for the Vroom post. Are you going to do a video like Zimmy? /ubbthreads/images/graemlins/smile.gif
 
LOL... yes, I think I can video it. It kinda sounds like an outboard boat motor at the moment as I only have the header on the car.
 
Oh cool, that's a good sound.
 
[ QUOTE ]
LOL... yes, I think I can video it. It kinda sounds like an outboard boat motor at the moment as I only have the header on the car.

[/ QUOTE ]

LOL to that. I was taking my wife for only her second spin in my '77 Midget when I started hearing an exhaust leak from under the bonnet. I decided to turn around and head home as quick as possible (even though the "prepare to walk" light had not lit up). On the highway headed home the tail pipe separated from the header completely, it was very loud at 60 MPH. Ironically, the first time she rode was on my test drive and we ran the car out of gas.
 
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