Replacing manifolds - how easy?

[TrevS]

Hi all

I am looking to replace the manifolds on my series 1 e-type as they are not in great condition and I would like to enhance the appearance of the engine bay. I've never replaced manifolds before so how easy are they to replace? Will I need any special tools and what gaskets and sundry items do I need for the job?

Any help is much appreciated

Thanks

Trev

[David Oslo]

Assuming you are talking about the exhaust manifolds.

Easy job, just spannering with a 1/2" AF along the block, and then 1/2" or 9/16" AF socket (memory fading) on some long extensions from below, to get to the exhaust pipe flanges. You'll need exhaust gaskets for the block and for the downpipes. It's good to change out the brass nuts at the same time, you'll maybe find that they've chewed up the threads a bit anyhow. Cheap and cheerful, and improve the cosmetics too.

On the Haynes spanner scale I'd put this at a 1 or 2 :D

[christopher storey]

Trev : what are you going to replace them with ? new ceramic coated manifolds suffer from the same problem as the old ones - once you get water from road spray or rain on a hot manifold , they start to degrade rapidly , so that 12 or 18 months on, you are back where you started . It is different , of course if there are structural defects like cracks or broken out studs . The quickest and cheapest visual improvement comes from a 1/2 inch brush and barbecue , or motorcylcle exhaust , paint

[abowie]

As David says.

The only tricky bit is getting to a couple of the 9/16AF brass nuts that hold the pipes onto the manifold flanges. I do this from below using two 3/8" drive extension "wobble" bars. I use a long one and a short one to get around the frame rails and the exhaust. Easier with the car on a hoist.

Otherwise it's about 30 mins work.

[cactusman]

Agree with the above. They are fiddly but not difficult to remove. Worth putting a lump of wood under the front part of the exhaust pipe to support it. Get new nuts all round. Do not be tempted by use steel ones. They must be brass. You will also need two sealing rings where the pipes fit into the manifolds, and while you are there it makes sense to the place the manifold gasket. I had to carefully angle grind the old rings off the ends of the exhaust pipes.

Once you have the manifold off then spend a merry hour or two with wire brushes and a drill and grind any remaining enamel and as much rust as you can. Then use a good quality exhaust manifold paint. I gave mine three coats with time to dry between coats. Did it last march and so far they still look nice tidy Matt black.

Cost very little but time. When they need doing again I will simply repeat. Good luck.

[Heuer]

For the sake of accuracy the original nuts were bronze rather than brass IIRC

[mooney1el]

For the sake of accuracy the original nuts were bronze rather than brass IIRC

On our aircraft exhaust systems, we use inconel bolts and nuts (austenitic nickel-chromium-based superalloy). That is what I used on the "spare" engine and will be using on the real original engine. More expensive but won't be heat effected.


Richard

[cactusman]

Yes...typo...bronze not brass. Dissimilar metal to steel studs so they don't "rust weld" together with the heat I believe. Lashings of copper grease is also a good plan.

If you can get aircraft stuff and are not bothered by absolute originality (I am not) then I am sure they would be even better.

[rolando38]

allow me not to share the same opinion with my above colleagues on this supposedly easy job...yes, it is , only if nothing breaks

but in my case 50% of the studs between manifold ans exhaust broke, and same with the fasteners between manifolds and engine
and then you're in deep guacamole...

and this despite extensive usage of WD40 , and persuaders of all kind

[nefematic]

May I agree with Rolando38 - the bottom nuts holding the manifolds are not easy to come at. To get them off took me the greater part of a saturday. Maybe it had to do with the heat shield and a/c hoses blocking part of the access. Mine had to come out to take out ripped and fit new studs for the downpipes. Before reinstalling check the manifold surface. Mine were slightly uneven, I got them planed before putting them back on.

[Alty Ian]

If the manifolds have not been removed for a long time, the risk of shearing off studs is very, very high unless extreme care is taken.

Nuts should be heavily lubricated and repeatedly loosened and re-tightened very gradually until they become loose enough to remove.

If resistance increases, stop and re-tighten, re-lubricate and start again.

If a stud does shear then it isnt impossible to replace it and often exhaust studs do get quite corroded and need replacing anyway.

Just take care when you do it.

[malcolm]

Yeah, one of mine broke as well. MY E type man got it out and sorted it though, and car looks much better now with new rather than rusty manifold.