Cannot Restart When Hot

PostPost by: LaikaTheDog » Thu Apr 15, 2004 8:22 pm

Been running my +2 now for a couple of weeks, but twice I have been caught out at the gas station.

when hot, i turn off ignition, then restart just perfect, but if i leave it for a couple of minutes i cannot restart, it catches a couple of time but just does not run, as a result i have run the battery down twice and had to sos the wife ! very bad for lotus credibility in the home...."sure honey, its as reliable as the saab, lets go on holiday in the lotus..." is not an arguement i can now win...

I figure it to be one of two things - poor state of tune - am i running too rich and flooding when hot ?

or i suffer fuel vaporisation and the the mechanical pump is not up to getting fuel to the carbs before the battery dies ?

I have dellorto's, but the chambers have fuel when i checked just now, so it is not evaporating while hot after a run, at least not this time...

runs like a dream once it starts
cold start is perfect every time

help is appreciated
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PostPost by: type26owner » Thu Apr 15, 2004 8:44 pm

Classic heat soaking and the fuel percolates out into the cylinders. Webers do it too. VERY SLOWLY to minmize the accelerator pumps from making the situation worst open the throttles via the pedal. Click it over with the starter for an instant and wait ten seconds. After the fourth cycle try releasing the pedal and it should startup reluctantly. Don't pump the pedal.
Regards,
Keith
p.s. Been doing lots of reading on this subject lately and this info was in there.
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PostPost by: freddy22112211 » Thu Apr 15, 2004 8:57 pm

Resetting the carburetor floats as described in the manual helps a bit.
Most people start a flooded car by flooring the throttle (slowly!) and then 'churning' the motor for 10 secs or more. Usually it catches properly on the third try.
Gordon
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PostPost by: type36lotus » Fri Apr 16, 2004 12:09 am

My Coupe' exhibits the same issue. I simply open the throttle about 1/4 and crank. It usually starts right up. Revs a bit so be ready to let off the throttle.

Mike,
66 S3 Coupe'
Mike Geiger
66 S3 Coupe', no more :-(
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PostPost by: 1964 S1 » Fri Apr 16, 2004 4:01 am

...is your vent line still blocked? (old evaporate problem on elan.net) .... does it happen only after putting fuel in? I think it's a pressure problem, how's the fuel pump?
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PostPost by: steveww » Fri Apr 16, 2004 10:13 am

It is not just a Weber / Dellorto thing my Stromberg S4 does it as well. I have read in a manual somewhere the best way to hot start is open the throttle full and hit the starter. Obviously jump off the pedal once it fires :o

The only other option is to open the lid and let it cool down a bit before starting it up.
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PostPost by: simon.mitchell » Fri Apr 16, 2004 11:12 am

My Sunbeam Alpine, running on twin Zeniths, used to do exactly the same thing when hot when I first got it - I used to dread stopping for fuel as it was hit or miss whether the thing would start again afterwards.. I found that it was running rich and tuning / balancing the carbs as per the manual improved things greatly.

Good luck!
Simon
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PostPost by: freddy22112211 » Sat Apr 17, 2004 8:24 pm

I wasn't very accurate when I replied before - what I should have said is that Miles Wilkins says in his book on the twin cam that in cases of persistent flooding one should set the float levels to the European spec. - 17mm instead of 15. I've copied the relevent pages onto my site - see <a href='http://www.lotuselan.de/tech/tech.htm' target='_blank'>http://www.lotuselan.de/tech/tech.htm</a> - tip number 11. I did it last year - it's not perfect, but it seems somewhat better.
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PostPost by: LaikaTheDog » Sun Apr 18, 2004 7:43 pm

interesting,

I had the dellortto's rebuilt last year, they are indeed set to 15, I will try at 17 and let people know how i get on, in the mean time, the throttle open 'fix' appears to work, I am uncomfortable with it as i never used to have to do this, I will also have the car tuned, hopefully this week on the rolling road.

thanks for the tips everyone
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PostPost by: LaikaTheDog » Tue Apr 20, 2004 3:56 pm

took the lotus to the rolling road at redline tuning (i have put details in the business listings),

I have known Tony who runs Redline for over 15 years, he is my local specialist for dellorttos anyway. but i have been taking MGs and mini's there since i was a teenager.Tony's diagnosis is
sadly, that my dellorttos have twisted spindles which has led to my fast idle (1500rpm), bad balance and poor starting when hot, also my coil is giving a very poor spark, so my carbs are coming off and new lucas sports coil needs to sourced.
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PostPost by: steveww » Tue Apr 20, 2004 4:15 pm

You can get a sports coil from just about anywhere. Burton do the Bosch coils and I have been told good things about the Aldon Flame Thrower coil from Aldon Automotive. My S4 runs with a Bosch blue coil and a big fat spark so I use 0.8mm gap for a better burn.
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