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Can the incline of the side of the road affect the starting ability of our cars? Some of the roads in Alameda have very steep cambers where they make the car lean -a lot- to the passenger side.
 

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Can the incline of the side of the road affect the starting ability of our cars? Some of the roads in Alameda have very steep cambers where they make the car lean -a lot- to the passenger side.
Looking at twin SU HS6 carbs they do indeed depend on gravity for proper functioning and USD would not function at all.

BTAIM, most carb-related (only) hot start problems imply too-lean settings and/or improper float bowl adjustment (assuming the fuel pump is ok).

On the next hot start attempt try this - all accessories/lights/etc. OFF, trans in N, clutch on the floor, choke fully disengaged and gas pedal hard to the floor.

Engage the starter in 5-10 second bursts but do not lift the gas pedal.

When the engine makes the first effort to start keep the starter engaged and the pedal on the floor.

As the engine catches up to the starter's revolutions disengage the starter while working the gas pedal to clear the carbs as the engine gains full operation.

Another hot start option is to richen each carb about six flats then re-adjust with the engine running.

Heyyyy! - how about running 225-95-15s on the right and 155-25-15s on the left?!

George Dill
 

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George, I would think that a hot start problem is more likely related to rich operation, not lean. In which case, I would agree with you that holding the gas pedal to the floor is the best approach ... But if the problem was lean, it would be the opposite, or a little choke ...
 

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Bikeymikey -

Is it only when the car is leaning, or does it happen on the flat as well? If the latter, could be the battery cable to the starter is getting too hot and losing conductivity. How close is it routed to the exhaust manifold?

Phil in nearby Berkeley
 

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Bikeymikey -

Is it only when the car is leaning, or does it happen on the flat as well? If the latter, could be the battery cable to the starter is getting too hot and losing conductivity. How close is it routed to the exhaust manifold?

Phil in nearby Berkeley
It will probably happen regardless of the grade that your car is on. It's just a characteristic of carbed vehicles. When you cut it off, it's going to momentarily get warmer in the engine bay. If you attempt to restart after a short while, it's still going to be hot and need more fuel to fire up. I wouldn't say this means anything is wrong with your car. It's just something you live with. No computer in there telling something to put a certain amount of fuel in a certain place.
 

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Discussion Starter #6
Looking at twin SU HS6 carbs they do indeed depend on gravity for proper functioning and USD would not function at all.

BTAIM, most carb-related (only) hot start problems imply too-lean settings and/or improper float bowl adjustment (assuming the fuel pump is ok).

On the next hot start attempt try this - all accessories/lights/etc. OFF, trans in N, clutch on the floor, choke fully disengaged and gas pedal hard to the floor.

Engage the starter in 5-10 second bursts but do not lift the gas pedal.

When the engine makes the first effort to start keep the starter engaged and the pedal on the floor.

As the engine catches up to the starter's revolutions disengage the starter while working the gas pedal to clear the carbs as the engine gains full operation.

Another hot start option is to richen each carb about six flats then re-adjust with the engine running.

Heyyyy! - how about running 225-95-15s on the right and 155-25-15s on the left?!

George Dill
Sorry George, USD, BTAIM? Not sure what that means. I will advise my wife (this happened when she was driving the car) of the procedure. Maybe I'll get new tires...

Bikeymikey -

Is it only when the car is leaning, or does it happen on the flat as well? If the latter, could be the battery cable to the starter is getting too hot and losing conductivity. How close is it routed to the exhaust manifold?

Phil in nearby Berkeley
Hey Phil,
Greetings from the balmy island of Alameda.
I haven't looked at the batter cable to the starter, but this only happened twice, once with me and once with my wife, both times when the car was hot and leaning heavily to the right.

It will probably happen regardless of the grade that your car is on. It's just a characteristic of carbed vehicles. When you cut it off, it's going to momentarily get warmer in the engine bay. If you attempt to restart after a short while, it's still going to be hot and need more fuel to fire up. I wouldn't say this means anything is wrong with your car. It's just something you live with. No computer in there telling something to put a certain amount of fuel in a certain place.
Andrew, I can live with that. The only time I had difficulty starting the car was when I was up in Pollock Pines, at some 3000 ft elevation. Adjusted the jets, and boom, voila.

To everyone: I feel like a broken record, but I cannot say how much I appreciate your help.
 

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Yeah, elevation is gonna throw you a loop as well. I just bought a 244 that came from 7000 ft and had it sent out here to NC where I'm at 800 ft. So yeah, some elevation change will do that to ya.
 

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The car would have to be parked at a dangerous angle (as in close to rolling over) before it would baffle the carbs enough not to start. Hard hot starts are usually due to over-rich mixture.
 

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Hot starts on a Volvo car with twin SU HS6 carbs:

The purpose of the wide open throttle (no choke) is to maximize the amount of fresh air entering the carbs. If the carbs are set very lean the hot start will be more difficult and require more cranking.

The heat from the exhaust manifold/header plays a big role in the hot start problem. Some folks have improved on the stock heat shield/drip pan...

http://www.cwnicholls.com/spitfire06.jpg

...oops...

http://www.flickr.com/photos/blue65pv544/4765679942/

...by adding heat-proof washers/spacers to move the shield closer?/farther? relative to the manifold.

Keep in mind that many other factors can cause hard starting hot or not - timing gears off one notch, wrong ignition timing, wrong valve adjustment, worn cam lobes, wrong dwell setting, wrong carb adjustments, dirty float bowls, crud in jet tubes and needle valves, faulty fuel pump, too much/little fuel pressure, wrong needles/jets, faulty carb linkage/choke setup, dirty gas/fuel filter, failing coil, poor battery cable connections, wrong/bad spark plugs, old plug wires, wrong/bad condenser, reading all the junk on the www...

George Dill
 

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Discussion Starter #10
Sorry all, but i was wrong, and phil in bezerkley might be on the right track. It seems like it might be a battery/charging problem. starter doesn't turn, but a pushing it to start will get it to go. one of my headlights is out and my radio is starting to cut out too. how do i diagnose where the problem lies? i have a tester, but don't really know how to use it.

phil, the cable to starter is routed in the same manner as all the other ones i've seen.
 

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Sounds like maybe a grounding and/or charging problem? In which case it wouldn't necessarily be related to engine temperature - that could just be a coincidence. Check that all your connections are tight and corrosion-free, including the Bat+ on the generator/alternator and the stud on the starter where everything is tied together. Be sure the green wire to the starter is seated securely too.
 

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Discussion Starter #12
Sounds like maybe a grounding and/or charging problem? In which case it wouldn't necessarily be related to engine temperature - that could just be a coincidence. Check that all your connections are tight and corrosion-free, including the Bat+ on the generator/alternator and the stud on the starter where everything is tied together. Be sure the green wire to the starter is seated securely too.
thank you.
 

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Discussion Starter #13
update: the battery was bad. and there was tons of corrosion. so out came the sand paper and dielectric grease, in in came a new battery. starts up every time.

thanks all!
 
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