Inlet manifold vacuum connections

[calum]

Hi.

My first e-type arrived this morning! It's an unrestored 1973 2+2 in red. Not perfect but seems like an honest enough car. Very excited anyway - but a few issues with running. I've checked all plugs, leads, rotor arm and distributor cap and apart form having one plug that's different (strangely - I'll get that sorted) everything else seems nearly new. Plugs were not too bad apart from a few being a little bit sooty and one being petrol washed. There were a few pipes split and clips missing so have tried to do a little under bonnet tidy up.

The question I am left with (today at least!) is:

What is meant to connect to the vacuum connections that project towards each other from the inlet manifolds? One of mine was connected to the 'valve' towards the ram air end of the air intake but not sure if that's right? I've had a look through the manuals and can't find any references to these ports.

The other one on that side did not have anything. The two on the other side did not have anything connected at all.

Are these vacuum outlets and should they have something connected or be capped? I did not think to run the engine and stick my finger over to feel for vacuum and the car is reversed into the garage now so I would rather not contaminate my lungs with any more unburnt fuel today!

Found a good picture! These little things that protrude, facing each other on the sides of the induction manifolds that 'face' each other on the same cylinder bank. They have masking tape on them in this picture.



Thanks!

Calum

[vee12eman]

Hi Calum,

Welcome to the forum and welcome to the Series 3. I have a Series 3 2+2 I restored so I will have a look at the connections later on and see what I can see. However, I do know the connections varied quite a lot with market, year (even month) of build and whether emission controls was fitted. Can you tell us more about the car - e.g. UK/US spec, LHD/RHD (won't affect the connections but indicates more info) date of manufacture. Give Jaguar Daimler Heritage Trust a ring, they may tell you manufacture dates over the phone and will talk you through obtaining a heritage certificate which will give you a lot of useful info, including the manufacture/sale dates plus info on first owner in many cases, also the market the car was destined for - they migrate!.

I am not an expert on the engine and vacuum connections, but with more info, somebody should be able to help. It's quite possible the wrong manifolds were fitted at the factory due to shortages and then unused connections blanked off. The image you have posted appears to be an XJ12, maybe these differ, but they may have been the only mainfolds available on the day of manufacture.

Did you try the parts manuals, or just the workshop manuals? I think both are available on the forum under the knowledge base section - note you have to be logged in to be able to see it.

Regards,

Simon.

[42south]

Hi Calum
Hope you enjoy your etype. I have a 71 V12 with carbs. On mine those two vacuum pipes are larger and connect together via a rubber t piece to a balance pipe that runs across to the two manifold connections on the other side. I assume its to promote smoother running.
Your engine appears to have had a lot of work done on it, or it is from another car. The brake master appears to be from a later saloon, maybe the engine is as well.

[42south]

Further to my post above. I just went and had another look at my manifolds. They are different to yours in that the balance pipe connections are above the small connections that you have pictured. So you don't have a balance pipe connection.
I do have one small connection the same as your picture, it connects to the inboard side of the air cleaner housing, as part of the warm air flapper arrangement on the air cleaner trumpet. This is part of emission control and could be blocked off with no adverse effect.

[Alty Ian]

Hi Calum

Firstly congrats on your car, I have the same one. Is yours an early S3 or a later one? there are differences, I suspect its a later one. See this for more info on originality.
http://www.jcna.com/library/concours/2007/e-type3.pdf

The picture you have posted isnt from an e type, where did you find that? looks like its a V12 saloon engine bay?

The two small vacuum conns on the drivers side on the inside face of each inlet manifold, one goes to the distributor advance retard, the other should be blanked off.

On the other side, one goes to the adsorbtion canister in the air filter, god knows what it does, it never seems to make any difference to how mine runs whether its on or not.

Best of luck

Ian

[calum]

Thanks for the welcomes!

Some more info for you. The car is a UK car. From what I can tell there's no emission control apart from the air intake flapper valves. It was registered May 1973. I think from memory the build date was February or March 1973 but I'll need to check that again. It's a later car. Chassis no 1S51787BW. V5 says it was auto but is now a getrag 5 speed.

It was converted to LHD by a jaguar specialist near Clevedon (Bristol Classic and Sports Cars, I think) as the previous owner lives in France now and took it over there. It's been stored for about 5 years in France and he was re-commissioning it for French MOT and registration but has his sights set on a Bentley (as the e-type is a bit small for him). I heard it was available so snapped it up. The previous owner had it since 2002.

The picture I have used above is not my car (mine is nowhere near as clean as that! And mine is a solid red colour). I will try and get some pics of mine posted at the weekend. Only reason I used that pic is it gave the clearest view of the small connections I was describing.

Good idea on the parts manuals - I had only looked at the workshop manuals.

Apart from some bad paintwork and a modern stereo the car seems to be pretty much original. But I guess I'll find out more as my journey of discovery continues!

One further thing I've noticed - the fuel pump ticks slowly with the ignition on without engine running. Is this normal or do I have something leaking/ passing? I have found it has the blue metal fuel filter in the boot. There is some smell of fuel from the car but I haven't identified any definite leaks yet. Maybe some of the hoses are porous/ needing changed.

Also need an interior rear view mirror and a couple of door mirrors. There is one on it (on the original drivers side...) which is also so blemished as to be useless. And one of the seat belts doesn't retract. And the heater blower is on its last legs. I think it may need a set of brushes.

Lights were also converted to LHD by the PO so I'll need to change them back for the MOT. Are they just standard Lucas 7" H4 units?

Thanks again,

Calum

[calum]

Looks like I've found my answer here:

http://www.sngbarratt.com/CatalogueProd ... 55&a=16583

C.37021 Blanking plug for stub pipe on front manifolds - not ex/em

Thanks for pointing me in the right direction! I'll get them blanked off.

Calum

[calum]

Hi.

A bit more research suggests that the vacuum pipe from the flapper valve on the air intake trumpet should run from/ to a thermostatic valve mounted on the air filter box. The pipe from the inlet manifold runs to this thermostatic valve. When the car is cold the inlet vacuum should keep the flapper valve in the air inlet trumpet closed, meaning that air is drawn in over the exhaust manifold and thereby 'pre-heated' to some extent.

Main issue I have is that the thermostatic valves are nowhere to be seen and having the flapper valve pipes connected directly to the inlet manifold means they are closed all the time that the engine is running. OK when cold, not so good when up to temp. So I think I'll disconnect them and blank all four inlet manifold ports for now.


Thanks,

Calum

[Alty Ian]

One further thing I've noticed - the fuel pump ticks slowly with the ignition on without engine running. Is this normal or do I have something leaking/ passing? I have found it has the blue metal fuel filter in the boot. There is some smell of fuel from the car but I haven't identified any definite leaks yet. Maybe some of the hoses are porous/ needing changed.

Calum

That is normal. Fuel is pumped continuously to the carbs via the pipe on the offside and there is a return line on the nearside. If you open the boot and remove the luggage rack base, you will hear the returned fuel going back into the tank. If the car has stood a while its quite likely you will have some minor leaks from hard hoses or if one of the fuel tank breather hoses is cracked or loose or missing (there are 3 hidden on the top back of the tank). You would be well advised to carefully follow all the hoses from tank to carbs with the ignition on and see where the leak is coming from.

The other thing that can drip is the plug/seal over the main jet at the base of each carb.

cheers

Ian

[calum]

Hi, Ian.

I thought I could hear something flowing back to the tank - thanks for confirming.

Calum