Engine mounts Se4

[[email protected]]

Not sure where to post this on forum - but hope it adds sommat to knowledge base.

When rebuilding my SE4 Sprint spec I came to the refitting the engine mounts.

I have dellortos and have always had a mighty struggle to fiddle on the rear lower carb nut. This with Carb side mount off & jack under sump etc)

After much research I found that the carb side mount was correct (straight flanges) but was fitted upside down and a bolt fitted through to restore some element of fail safe. Yuk!!!. On fitting the right way up, the cant on the engine immediately showed better access to the back carb lower nut. BUT as my bonnet does not have a carb bulge (engine originally fitted had Strombergs) There is clear evidence that the front edge of the cam cover was hitting the underside of the bonnet.

After much measuring & mount removal & refitting ( Headers & Starter motor not fitted - thankfully!!) I worked out that an exhaust side mount (scalloped flanges) fitted on the carb side would give sufficient engine cant to improve back carb lower nut access plus give acceptable clearance twixt cam cover & bonnet

Top tip !! clearance confirmed by sticking a line of plumbers mate twixt strips of Asda's smoked ham packet plastic cover; running the resultant sandwich along cam cover front edge then dropping the bonnet on) resultant squidge shows a minimum 6mm clearance.

I am also going to fettle & remake the Fibreglass "drop" where it goes under back carb to further aid carb hand clearance hope this is of use

[William2]

I had exactly this problem when I rebuilt my S4 several years ago. I did the same and fitted an exhaust mount on the carb side. To overcome the airbox hitting the upper footwell grp area I cut slot out about 3/4" wide and re-fibreglassed it with several layers of matt.This now gives sufficient clearance on the airbox and cam cover. I don't expect there is any benefit but it also means that the fuel level in the Dellorto float chambers is more level than on a canted engine.

[alan.barker]

Sorry but,
I would say that both of your cars have had a chassis change and the new Chassis was not fitted correctly.
The front of the Camcover clearance with Bonnet should be checked when positioning Body on new chassis. Shims should be used between Body and Chassis Mounts.
I can understand your way of fixing the problem and it's your choice why not.
Bob,
i hope before you fitted the Engine Mount on the exhaust side you put the Exhaust Manifold in place and held it to one side. Before attaching the Engine Mount. i think you will have problems sliding the Exhaust Manifold into place if the Engine Mount is already attached.
Sorry again if my post seems negative
Alan

[William2]

Alan, as a point of interest my car has the original chassis. I could have shimmed the body using penny washers but have never liked the idea. Not to say I don't have the odd shim washer here and there to take up any deficiencies in the body moulding but from an engineering perspective I preferred that the body sat close to the chassis lower flange.

[alan.barker]

Hi William,
like i said i can understand the way you fixed it.
There is one good thing to use the same Engine mount on both sides is more logic and cheaper. The Exhaust side one is the same as the old Ford Anglia 105E and not a Lotus special.
I must say it is strange with an original Chassis that the Camcover touches the Bonnet. Unless you car was not a Big valve (which is higher and more square) and it now has a Big Valve Camcover
Alan

[alan.barker]

Hi William,
i just thought your car has the original Chassis but has the Body been lifted off the Chassis at some time.
Then the Body was refitted. I know that with the Chassis after several years they do get a little tired and the Front turrets do approach one another which means that the sides of the Engine bay get pushed in. This means the Bonnet sits at a lower position and can allow contact with the Camcover.
I had this problem on a 1970 +2S 36 years ago and it was the first signs that the Chassis needed replacing. I then fitted a Lotus Galvanised Chassis from Miles Wilkins.
Alan

[RogerFrench]

There's another odd point.
The car doesn't have a carb bulge because it originally had Strombergs? That's bass-ackwards!

[alan.barker]

+1
the Bonnet Bulge was for Strombergs not to touch, nothing to do with Webers. having said that there were cars with bulge Bonnets and Webers to use up the stock of Bulge Bonnets. Many +2 Elans in 1970 with Webers had Bulge Bonnets but it was never to clear the Webers. Chapman wanted to get rid of old stock.
Alan
ps. How i understand it ALL Stromberg cars had Bulge Bonnet.
SOME Weber cars had a Bulge Bonnet
Please correct me if i'm wrong no problem

[William2]

Alan, I restored the car totally and had the body off. I checked the chassis thoroughly and found only minor surface rust in places and no signs of corrosion on the front turrets. Front box member was fine, but I realise that it can rust from the inside as well!! The chassis also showed no signs of any stress cracks around engine mounts, etc. It also looks like the body has the original front end on it. I do not know the full history of my car but have heard of other Elans still running on original chassis. I have to admit I was a bit surprised to find out that the chassis was original but have no history of the cars mileage so maybe it has seen little use relatively. I hadn't heard of the scenario of the turrets getting pushed closer together unless there was fairly serious rust in that area. Fingers crossed mine will last a few years longer! There have been previous threads on the forum regarding bonnets hitting the cam cover and never getting to the bottom of it. I know one thread was mine in search of solutions and causes.

[alan.barker]

William,
i think when you replaced the Body on the Chassis it just settled in a lower position which is a pity.
I used to have a 1973 +2S130 which was on its original Chassis also with no rust. having said that it had been off the road for 23 years in a dry garage. I was the 4th owner but i sold it about 2 years ago and now it's in Guadeloupe a french Island in the West Indies.
Alan

[[email protected]]

Bob Frost to William - thanks for the heads up on slotting the footwell top section to give clearance for the airbox I have fettled the whole thing down and re-glassed as close as I dare to the pedal upper bracket / steering column etc. Now loads of room to get hand under back carb and around 18mm clear under the airbox

Interesting my car has had 2 x chassis changes, 1 for rust followed 6 months later by a front prang according to the receipts I got with the car, So quite possible body chassis heights are not right. Also if I had known just how long it takes to do a thorough restore I would lifted the body off first.

At 71 I ain't quite as supple as I used to be!!! Great string - very interesting

[alan.barker]

It's good to know you have fixed the problem and can get out and drive your Lotus.

It's always seemed strange to me that Lotus Opted to make a special Engine Mount on the Carb side to stop contact with the Carbs and Footwell. Instead of changing the Mould which would have been very easy and dare i say much more professional.
Perhaps someone on the Forum can enlighten me
Alan

[ericbushby]

Alan, Was it done to raise the right hand side so that the carburettors were at a 5 degree angle.
Just something I heard once but I do not know what benefit this gives.
Eric in Burnley
1967 S3SE DHC

[alan.barker]

Eric,
you could have a good point there to stop petrol pouring out the trumpets. But to do the job correctly you would angle the Inlet Tracts more or simply raise the height of the Chassis Lug.
On the Lotus Seven does it have the same Engine Mounts both sides or Lotus Cortina, Escort Twin Cam, Cortina Twin Cam etc and the list goes on.
It just seems after designing the Lotus Twin Cam Head and all the work a bit of a diy bodge
Alan

[Chancer]

Austin A35 mounts on a Lotus7 sitting on the lower frame rails, fabricated tubular pyramid spaceframe type brackets from the mount to the engine block so plenty of scope for tweaking the height from one side to the other.