1972 Lotus Elan +2

[euroauto]

Having never had a Lotus Elan in the shop ( or even seen one up close until now) and no access to data or specs, I have the following questions:
- Where are the safest jacking points to put the car on the lift?
- What should I expect for healthy oil pressure with a shop gauge
(cranking, cold and warm)?

Thanks

[Guy Croft]

Hi,

I am sorry but as for jacking points I don't know exactly! See if this helps any:
http://www.lotuselancentral.com/repair/jackpoint.htm

As far as engine oil pressure, that I do know, 15-20 psi at tickover hot, and 55-65 psi under load hot. The idle oil pressure can be as low as 10 (on old rods, crank and bearings) but it must jump up when you blip the throttle. If it is less than 50 psi under driving conditions at engine speeds over 3000 or so, it really needs the bottom end inspecting.

I have friends at Lotus Sports and Performance division so if you get stuck let me know.

GC

[euroauto]

Many thanks.
Oil pressure when cold (at Idle) is 15 psi and raises as rpm increase.
This is as far as I got today.
Initial complaint was that the customer accidentally overfilled the crankcase, started the car, it made a "bang noise" and it threw a lot of the oil on the ground. I assume this may have come from the crank vent. He drained the oil to proper level and when he restarted the car , the mechanical gauge in the dash read much lower than before, which is why I have it here.

[Guy Croft]

JB,

overfilling with oil either causes the excess oil to be blown out of the breather or other 'orifice', and in the extreme can cause hydraulic locking, where there is so much oil in the crankcase that the engine cannot turn over, a bent rod can occur in the latter case, but I have never seen it, the starter (especially on an Elan) usually is not powerful enough to do that.

I have deliberately over-filled many engines equipped with oil pressure accumulators (using extra 1qt, 1.5 qt, 2 qt of oil) and certainly never experienced a cranking problem like this.

Whatever the client thinks about oil pressure my advice is to fit your own accurate capillary gauge and check it cold and hot.

If you suspect low hot pressure, which really matters under load, then you'd best advise to him an exploratory strip of the sump and bearings, to be on the safe side. I can't think of a reason why his over-filling and any 'low oil pressure' should be related. If he refuses the strip, get him to sign a refusal in writing and let him worry about thereafter.

GC

[euroauto]

Well , I finally made 10 minutes to spare with the Lotus. The info my customer gave me was a red herring.
The oil pressure was very low due to the sump being half full of fuel :!:
I changed the oil with Mobil 1 synth 15W50 (customers choice) and a Bosch filter. With my shop gauge taped to the windshield the car ran a little over 50 psi at about 4000 rpm.
I am not sure where all the gasoline came from. The spark plugs have a little black soot but the car runs and drives well with no indication of flooding. Choke levers are full off ....... :?:

[simon-spanner]

Has the car still got a mechanical fuel pump?

If so check the pump diaphragm isn't split- if that happens the sump can easily fill up with fuel.

Been there, done that- made a big mess of the bearings etc

[Guy Croft]

Well done, Simon,

very well-made point, this is of course the first mention of 'gasoline... where did it all come from?..'

And of course you are quite right that gasoline contamination of the oil from that cause (and others, eg: over-fuelling due to carb over-rich settings/out of balance or flooding - fuel pressure and float settings) could degrade the oil viscosity severely and reduce the oil pressure/potentially damage the bearings.

(See also GC V/W. I have written about this in ancillaries.)

GC