Lotus Elan

Engine Sudden Stalls

PostPost by: Lotus130 » Sat Sep 15, 2018 10:09 pm

I have a Lotus Elan+2/s with the following problem. Startup ok and runs perfectly but after few kilometers run, engine suddenly stalls with no means of engine startup. After 45mins engine starts again perfectly. It has a magnetic distributor. Wiring from distributor to coil and solenoid are tightly connected. Would like to hear if anyone has ever experienced such a problem and what was the solution. Regards Kenneth
Lotus130
New-tral
 
Posts: 1
Joined: 15 Sep 2018
Location: Malta

PostPost by: Andy8421 » Sun Sep 16, 2018 4:59 am

To run fine, then pack up when hot - only to work fine again usually indicates an electrical problem.

You should check whether you have a spark at the plug during the period the car is hot and won't start. No spark, definitely an electrical problem. If you have a healthy spark, then you may have a fuel vapourisation issue or a problem with the pump - although that would be unlikely.

There are a number of components in the ignition system that are heat sensitive. I have had coils, distributor caps, rotor arms and electronic ignition modules all work fine when cold, but fail as they got hot. Easiest way (if you have the spares available) is to substitute components until the problem goes away.

If you don't have the spares, then you will have to work your way through the system one step a time until you come across the bit that doesn't work.

edit: It is always possible you have a vacuum forming in the tank if the breathing system is blocked (although most of the posts on here about plus 2 tanks seem to have the opposite problem). A quick test is to undo the flller cap and see if the car starts. Unlikely to be the problem, but very easy to test for.
Andy8421
Third Gear
Third Gear
 
Posts: 232
Joined: 27 Mar 2011
Location: Surrey, UK

PostPost by: Sea Ranch » Sun Sep 16, 2018 5:47 am

Seems Andy has given an excellent rundown, Kenneth.

Clearly, the time to diagnose the problem is when there IS a problem, so you would have to bring tools and spares along on your next drive and be prepared to go through a checklist.

No question I would start, as Andy suggested, with spark at the plug; easiest thing to check first. Work logically from there.

I once had a bad ignition coil and did not have a spare to swap in, as a way to check. Spares can be expensive, but in the long run are a necessary bit of kit as we travel down the road of classic car life :wink:

Let us know how it turns out!

Randy
User avatar
Sea Ranch
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1172
Joined: 07 Mar 2011
Location: West Coast, Canada (Surrey, BC)

PostPost by: ericbushby » Sun Sep 16, 2018 9:34 am

Kenneth
My first thought is a failing rotor arm in the distributor.
Mine had a similar fault but did start misfiring before failing altogether. It recovered when cooled down.
It is quick, cheap and easy and may be due for renewal anyway.
As Andy says, check for a spark.
Best of luck
Eric in Burnley
1967 S3SE DHC
ericbushby
Fourth Gear
Fourth Gear
 
Posts: 692
Joined: 13 Jun 2011
Location: east lancashire

PostPost by: billwill » Sun Sep 16, 2018 10:20 am

ericbushby wrote:Kenneth
My first thought is a failing rotor arm in the distributor.
Mine had a similar fault but did start misfiring before failing altogether. It recovered when cooled down.
It is quick, cheap and easy and may be due for renewal anyway.
As Andy says, check for a spark.
Best of luck
Eric in Burnley
1967 S3SE DHC




But be sure to get a good quality one, there aree a lot of crap copies on the market.

Try the Distributor Doctor for a replacement.
Bill Williams

36/6725 S3 Coupe OGU108E Yellow over Black.
billwill
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 4500
Joined: 19 Apr 2008
Location: London UK

PostPost by: steve.thomas » Sun Sep 16, 2018 11:58 am

I had a similar problem recently which i thought was either coil or electronic ignition failing. I swapped out both but the problem persisted. Eventually i traced it to a partial blockage in the fuel tank outlet. It seems the pump could provide enough fuel at tickover, but after 20 mins driving it would starve. When cooled it would re-start fine, which implies fuel was syphoning from the tank to the carbs, which i have heard of before on the Plus 2 due to the relatively high position of the tank.
Regards
Steve
steve.thomas
Second Gear
Second Gear
 
Posts: 96
Joined: 24 Jun 2010
Location: Gironde, France

PostPost by: Harvey » Mon Sep 17, 2018 2:23 am

An engine needs both spark and fuel to run. If you are getting spark delivered at the right time and the car will not fire then I would check to see if the carbs are getting fuel. This can be tested by pulling off the fuel line to the carbs, placing the line in a bottle and then turning on the ignition if the fuel pump is electric or simply cranking the engine if the fuel pump is mechanical. Be quick to turn the ignition off however because the bottle will fill pretty quick if the fuel pump is working.

I have had two cars, one on SU carbs, and one on Strombergs where the inlet jet to the float bowl became partially clogged not allowing enough gas to keep the float bowl filled so that a few miles into a drive one of the carbs would starve two of the cylinders and the car would lose power. Not quite what you are experiencing here but fuel delivery problems can take many forms.

Lee
Jackson, CA
Harvey
Second Gear
Second Gear
 
Posts: 73
Joined: 21 Aug 2010
Location: Jackson, California

PostPost by: nigelrbfurness » Mon Sep 17, 2018 11:15 am

My money's on the coil - try that first.
1970 S4SE/1760cc big valve/SA-AX block, L2s, 45DCOEs, 1978 Jensen GT, 1962 AH Sprite, Alfa-Romeo 159, 1966 Bristol Bus, 1947 AEC Regal bus.
nigelrbfurness
Third Gear
Third Gear
 
Posts: 331
Joined: 04 Apr 2008
Location: Dunmow, Essex, UK

PostPost by: alan.barker » Mon Sep 17, 2018 4:00 pm

For me it's for sure the Condenser made in China. The last one on my car lasted 80 kms :shock:
Fit a Hall effect sensor in the dissy and throw away the Points + Condenser.
Or buy from "Distributor Doctor" :wink:
Alan
Alan.b Brittany 1972 elan sprint fhc Lagoon Blue 0460E
alan.barker
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1627
Joined: 06 Dec 2008
Location: BRITTANY FRANCE

PostPost by: pauljones » Mon Sep 17, 2018 7:49 pm

I agree with coil. Next time touch it with back of your hand. It may be very hot so be carefull. Have you left your ignition on by chance in the past? Mine done exactly the same. I fitted the luminition sports coil but quickly went to Aldon for the ignitor 2, matching coil and leads. Worked a treat. I went to efi after so i kept them as they were so good. I know some have fitted a bosche coil. Blue i think. A simmilar sports coil with good results.
Kick the tyres and light them fires...!!!!!!!
pauljones
Fourth Gear
Fourth Gear
 
Posts: 985
Joined: 09 Feb 2008
Location: Gosport sur la mer,South hants

PostPost by: alan.barker » Tue Sep 18, 2018 1:59 am

If you have a "HALL" effect sensor fitted did you remove the pip on the Base Plate and also use the Thermal Grease :wink:
Alan
Alan.b Brittany 1972 elan sprint fhc Lagoon Blue 0460E
alan.barker
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1627
Joined: 06 Dec 2008
Location: BRITTANY FRANCE

PostPost by: mbell » Tue Sep 18, 2018 2:12 am

Worth checking but some sensors have a holes pre drilled hole to avoid that issue. My pertonix did.
'73 +2 130/5 RHD, now on the road and very slowly rolling though a "restoration"
mbell
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1286
Joined: 07 Jun 2013
Location: Austin, TX (UK Ex-pat)

PostPost by: worzel » Tue Sep 18, 2018 4:08 pm

Hi

My own experience- I had an alarm fitted that was wired to disable the ignition. In effect the alarm control box was being fed current continuously whilst the engine was running. It appears that these control boxes aren't designed to take a continuous feed.

Switching the circuit to the starter cured the problem. The symptoms were exactly as you describe.

Regards


John
worzel
Fourth Gear
Fourth Gear
 
Posts: 704
Joined: 13 Jan 2004

PostPost by: denicholls2 » Tue Sep 18, 2018 5:31 pm

Contrary opinion here. I don't know the susceptibility of the Webers/SUs to vapor lock, but the symptom is identical to vapor lock as I've experienced it.

I had an Audi 100LS that in the summer would stop, for example when stopping at a toll booth. Or in traffic in a tunnel trying to get someone to the airport for a departing flight. When it stopped, it wouldn't start. Wait 15 minutes, starts and runs fine.

I finally discovered that the fins on the radiator core had rusted to powder -- run your hand over them and they flake off. To the junkyard for a replacement, worked fine after that.
denicholls2
Fourth Gear
Fourth Gear
 
Posts: 543
Joined: 23 Jan 2006

PostPost by: alan.barker » Tue Sep 18, 2018 6:48 pm

Never had vapour lock in 43 years of driving lotus cars.
Alan
Alan.b Brittany 1972 elan sprint fhc Lagoon Blue 0460E
alan.barker
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1627
Joined: 06 Dec 2008
Location: BRITTANY FRANCE
Next

Total Online:

Users browsing this forum: No registered users and 6 guests