Lotus Elan

Engine numbers

PostPost by: BobC » Wed Jul 03, 2019 2:53 pm

Hi all
Not for the first time an engine number query. I have +2/130-4 that I am at an early stage of 'rescuing'.It was first registered May 1973 and according to the VIN plate the engine number is P29885. However on the ledge between the middle inlets very faintly stamped is 93837 and bolder stamped 116E. As part of the block casting is T2 and on the LHS towards the front 3M10. There are no raised casting letters/numbers at the rear LHS. My reading of this 116E - correct Ford 1500 Kent base engine, T2 - good block for over boring, 3M10 - casting date M, Ford year 1973, 3 - March - 10 -10th day. Carbs are twin Dellortos and the cam box says 'Big Valve'. I have full history other than only (!) the first 13 years of its life and no evidence of any major engine work. I have no idea why just the block would need changing, but then I am not steeped in Lotus engine knowledge. So either the block has been changed for a suitable Ford item (93837 being some Ford model sequence) or it is an original block and the real engine number lurks elsewhere. Grateful if anybody can shed any light on either of my theories. Many thanks. Bob
BobC
New-tral
 
Posts: 4
Joined: 09 Apr 2019
Location: Liverpool UK

PostPost by: Craven » Wed Jul 03, 2019 6:54 pm

If it’s a 116E block then your decoding of 3M10 is likely to be wrong, not good news as it would be 1963 March 10.
Craven
Fourth Gear
Fourth Gear
 
Posts: 852
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: promotor » Wed Jul 03, 2019 6:58 pm

If it's got "116e" engraved or stamped above the engine mount then that block would have been in a Ford car first as that's part of Ford's identification numbers, 116e referring to Consul Classic / Capri.
116e cast into the block is an actual part number.

Craven wrote:If it’s a 116E block then your decoding of 3M10 is likely to be wrong, not good news as it would be 1963 March 10.


I think the "M" is for December - it's the 13th number of the alphabet but in Ford's numbering system they don't use "i" so 13th becomes 12th.
Last edited by promotor on Wed Jul 03, 2019 7:06 pm, edited 1 time in total.
promotor
Third Gear
Third Gear
 
Posts: 485
Joined: 16 Mar 2012
Location: Derbyshire, U.K.

PostPost by: Craven » Wed Jul 03, 2019 7:04 pm

OK it was the year that concerned me as the difference between a 116E block and the later square cap, probably 701M in 1973 is chalk and cheese.
Craven
Fourth Gear
Fourth Gear
 
Posts: 852
Joined: 14 Sep 2013
Location: south coast uk

PostPost by: BobC » Wed Jul 03, 2019 7:51 pm

Thanks chaps. In anticipation of the block maybe having started life in a more humble animal, I am contacting the FMC Heritage Centre to see if they can shed any light. Will keep the Forum posted of any info they can provide. in the meanwhile any other comments would be appreciated.
BobC
New-tral
 
Posts: 4
Joined: 09 Apr 2019
Location: Liverpool UK

PostPost by: denicholls2 » Fri Jul 05, 2019 2:09 pm

BobC wrote:Hi all
I have no idea why just the block would need changing, ...


    Sustained use above 6500 RPM with stock crank
    Multiple rebores to minimum wall thickness or catastrophic piston failure
    Thrown rod
    Many others I am sure ...
denicholls2
Fourth Gear
Fourth Gear
 
Posts: 566
Joined: 23 Jan 2006

PostPost by: BobC » Sat Jul 06, 2019 8:57 am

Thanks for last reply. I am well aware of the generic issues and their reasons that can befall an engine. Perhaps i phrased my question badly as I was really getting at any Lotus/Ford specific issues that can affect this engine.
It would not be the first time a designer built in a problem, for example even the mighty Porsche got it very wrong with the M96 engine as fitted to the 996.
BobC
New-tral
 
Posts: 4
Joined: 09 Apr 2019
Location: Liverpool UK

PostPost by: 2cams70 » Sat Jul 06, 2019 12:29 pm

BobC wrote: for example even the mighty Porsche got it very wrong with the M96 engine as fitted to the 996.


Porsche aren't mighty. Cosworth were way, way better. They set the standard by which all modern engines follow including Porsche
1970 Ford Escort Twin Cam
1972 Ford Escort GT1600 Twin Cam
1980 Ford Escort 2.0 Ghia
Peugeot 505 GTI Wagons (5spdx1) (Autox1)
2015 Honda City 5spd.
2cams70
Fourth Gear
Fourth Gear
 
Posts: 638
Joined: 10 Jun 2015
Location: Australia

PostPost by: rgh0 » Sun Jul 07, 2019 12:18 am

BobC wrote:Thanks for last reply. I am well aware of the generic issues and their reasons that can befall an engine. Perhaps i phrased my question badly as I was really getting at any Lotus/Ford specific issues that can affect this engine.......


The Twincam had no particular weakness except perhaps for a tendency to leak a little more oil than usual for engines of that period due to the front timing chain case design. It is a strong and reliable engine in road trim that can take a lot of enthusiastic use up to the 6500 rpm rev limit.

Operating life between the need for rebuilds was also perhaps shorter than some engines due to the relatively short valve guides and no oil seals on the valve stems leading to smoky engines and the very rich tuning of the Webers leading to excessive fuel in the cylinders washing oil off the bores resulting in more rapid bore wear.

Replacement of engines however is very common as the cars tended to have a hard life in their first 10 to 15 years being driven hard and often being maintained poorly.

There is nothing inherently wrong with an early 116E block versus the later 701M block. The round main bearing caps on the 116E block are fine on a road engine.

regards
Rohan
User avatar
rgh0
Coveted Fifth Gear
Coveted Fifth Gear
 
Posts: 7069
Joined: 22 Sep 2003
Location: Melbourne, Australia

PostPost by: BobC » Sun Jul 07, 2019 2:12 pm

Rohan Thanks for that, I suspected that the 116E would not have any major problems, it is a five bearing crank so should be pretty robust. The car will only be used for light road use when refurbished. I am in the process of taking the car down and the body is nearly ready to come off, so I can then get at the engine more readily and remove the sump etc. I have checked the cylinder pressures and they are all 160 psi +/-, so that is good.
BobC
New-tral
 
Posts: 4
Joined: 09 Apr 2019
Location: Liverpool UK

Total Online:

Users browsing this forum: No registered users and 2 guests