Lotus Elan

Missing Horses

PostPost by: Ramsden » Fri Dec 24, 2004 6:39 pm

Hi,

My Plus2 S130 has been lying idle for about 3 months. I took it out today to blow away the cobwebs to find that all was not well.

The engine starts and idles ok but seems to labour when under load. Under relatively light throttle this is not so apparent but under heavy throttle (regardless of the gear) there is no urge and the engine note drops, as it would if you floored the throttle in too high a gear. Similarly, climbing hills requires downshifting much earlier and by more than before. Overall it is as if something has chopped about a third of the horses off. You can get up to speed but it takes a long time and you lose it again fast if you hit a hill.

I also noted the car never quite seemed to warm up properly. The temp needle normally sits solidly at 85 but today it hung about the 75-80 mark until I left the car idling on the drive for a while. Could just be the season but it was about 10 degrees today so not overly cold.

Whilst off the road the car has been started and left to warm up approximately once every three weeks. It was very low on fuel when I returned to it which does make me wonder whether some rubbish from the bottom of the tank may have been sucked into the fuelling system and is resticting the feed.

Before its enforced idleness the car ran wonderfully, with enough tractability to pootle in 4th at 30mph, reving easily and pulling hard from about 3500 up to the redline.

I'm disinclinded to suspect some kind of resistance in the drivetrain/sticking brakes as I drove for about an hour without experiencing any odd rubbing noises or overheating smells.

Any thoughts would be most welcome.

Cheers

Simon
Ramsden
First Gear
First Gear
 
Posts: 32
Joined: 09 Oct 2003

PostPost by: type26owner » Fri Dec 24, 2004 6:54 pm

Possibly the fuel has gone sour. Try filling it with fresh stuff from a different filling station before doing anything else.
-Keith
type26owner
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1704
Joined: 18 Sep 2003

PostPost by: rgh0 » Fri Dec 24, 2004 9:39 pm

Retarded ignition will give the same symptoms of ok starting, no power and low engine temperature.

Rohan
In God I trust.... All others please bring data
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 8874
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: Ramsden » Sun Dec 26, 2004 2:49 pm

Thanks Chaps.

Keith, I've re-filled the tank with fresh stuff and am taking the car for a serios of runs in the hope that the goodness will seep its way through.....no luck yet.

Rohan, Could the (lumenition) ignition have become retarded whilst the car was standing? It ran fine in September when I last drove it regularly.

Cheers

Simon
Ramsden
First Gear
First Gear
 
Posts: 32
Joined: 09 Oct 2003

PostPost by: rgh0 » Sun Dec 26, 2004 10:57 pm

Simon

Its possible for the distributor clamp to work itself loose at any time and for the ditributor to move retarding the ignition. This usually happens when the distributor has not been fitted all the way into its socket ( which is easy to do given its inaccessible location)

Rohan
In God I trust.... All others please bring data
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 8874
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: pereirac » Mon Dec 27, 2004 12:33 pm

I had a similar sounding problem with my Elan (although after a longer period of idleness). I checked timing etc and eventually decided it was a fuel problem and stripped down the fuel pump ..to discover nothing wrong with it...
What I iescovered was that the small piece of rubber tube used to connect the fuel pump to the plastic fuel pipe had gone brittle and begun to split (although you could only see the split if you bent the pipe). It appeared that the more I accellerated the more the pipe split and the less fuel the engine received. When driving the car felt fine until I tried to accellerate quickly and the power just `dropped off`. At idle, a constant speed or if you accellerated slowly there were no problems...

The fix cost about 20p and the actual repair took 5 mins. Checking the timing, fuel pump etc took hours (taking off the carbs to get to the fuel pump is a real pain..) but I do have a nice clean fuel pump now!!

Just a thought!!

Happy New Year to everyone

Carl :D
Carl

72 Elan Sprint
87 Excel SE
97 Alpina B10

http://www.lotuselan.co.uk
User avatar
pereirac
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1136
Joined: 01 Oct 2003
Location: Cambridgeshire

PostPost by: Ramsden » Mon Dec 27, 2004 6:35 pm

Thanks chaps - gives me a few more ideas to check...
Ramsden
First Gear
First Gear
 
Posts: 32
Joined: 09 Oct 2003

PostPost by: type26owner » Mon Dec 27, 2004 8:17 pm

Check the condition of the battery and the charging system. If both are weak then very probably it will not build up enough voltage to fire cleanly under high loading conditions. It won't entirely cutout but it will intermittantly be misfiring on all the cylinders. It just sounds like it's labouring and it won't pull hard anymore. For this to happen the engine needs to be easy to start normally and you have to be rather deft (perhaps without even realizing it) with the ignition switch to coze it to start when it should not due to a low voltage condition. The clue here is if the engine only starts when the key is released.

The quirky cooling behavoir has been noted by me on the Yahoo list due most likely to the direct cooling of the engine by the wind whistling through the engine bay. Mike Causer made the connection that the same effect was also causing him carb ice problems on his newer style Elite. When it gets around freezing we both have to partially block off the airflow through the radiator or our engines will not warm up fully to the proper operating temperature. Turns out this a fairly common occurence on engines that sport an aluminum head(s) but have a cooling system designed for cast iron.
-Keith
type26owner
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1704
Joined: 18 Sep 2003

PostPost by: JACKJABBA » Mon Dec 27, 2004 8:30 pm

Carl, was there no petrol leak or smell of petrol with your split or was it pulling in air.
JACKJABBA
Second Gear
Second Gear
 
Posts: 84
Joined: 17 Sep 2003
Location: Middleton St George, Co. Durham

PostPost by: pereirac » Wed Dec 29, 2004 10:55 pm

There was no petrol smell that I can remember or even fuel leakage in the boot. The pump was just pulling in air when you pressed down hard on the accellerator!!
Carl

72 Elan Sprint
87 Excel SE
97 Alpina B10

http://www.lotuselan.co.uk
User avatar
pereirac
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1136
Joined: 01 Oct 2003
Location: Cambridgeshire

PostPost by: StressCraxx » Sun Jan 16, 2005 4:32 am

A couple of quick checks...

hook up a timing light to check your timing at idle. Make sure it is to spec.

spool the engine up to 3500-4000 rpm with the timing light on the mark. You should see the advance move further 25-28 deg

Check your vacuum hoses for cracks.

Spray some carb cleaner at the carb mounts to the manifold. A sudden increase in idle means a vacuum leak.
There is no cure for Lotus, only treatment.
User avatar
StressCraxx
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 1434
Joined: 26 Sep 2003
Location: San Francisco Bay Area, California

Total Online:

Users browsing this forum: gjz30075 and 7 guests