Talk Morgan Forums Morgan Sports Cars Morgan Plus Four, Supersport & Plus Six (CX & CXV Generation Vehicles) Hot Bonnet

I recently bought a 1989 Plus 4. It has the Rover M16 engine.

After driving it I noticed the bonnet on the left hand side is very hot. Too hot to hold a hand on it. The exhaust manifold is on that side, so it makes sense. But that can't be good for the paint (though it doesn't seem to be affected).

I'm thinking of making a heat shield of some sort to go over the exhaust manifold. Just a simple thing that would still allow air to flow over and under it, but keep the manifold from radiating heat upwards. I don't want to wrap the manifold with insulation.

Thoughts?

Rick

Hi Rick,

Congratulations on buying a great Brit car to add to your collection.

I have had two Plus 8's with manifolds on each side and I could fry an egg on either side bonnet quite comfortably I feel sure after a spirited drive, I have never seen any signs underside or topsides of the bonnets paint wise being damaged.

Same on one side only on my 4/4 Sport it does get warm under there but never any signs of water bottles or any other non metallic parts melting so all is well..

By all means put in a transparent (horizontally fore and aft) alloy fending strip if it feels like personalising, it can do no harm.

Enjoy your miles.

Might get more relevant thoughts if you posted the question in the Classics section, as here is for the CX generation cars. I can't remember what my T16 car was like for heat soak.

Might get more relevant thoughts if you posted the question in the Classics section, as here is for the CX generation cars. I can't remember what my T16 car was like for heat soak.

I had a 1993 4/4 with Ford 1.6 efi engine.
It came with a steel heatshield bolted onto the exhaust manifold. The air intake was a plastc/flexi pipe about 100mm(ish) that went above it so the intention was to protect that from high manifold heat. I had to replace the air intake pipe as it was deteriorating due to the heat in the area where it passed over the manifold that the shield was letting past.The replacement was a similar material but I wrapped it in reflective heat shield material. A simple job that worked. You could also stick some heat insulation to the bonnet. BUT....removal in a safe way of hot air so it doesn't affect components should be a priority, as is shielding components.
The Plus8 I moved to used to get quite "warm" under the bonnet! No overheating but attempts were made to improve airflow through. Rear bonnet extenders in summer, temporary air scoop/ducts as tests.
There is an option to wrap the manifold or ceramic coat it. There are discussions on the pros/cons elsewhere in TM plus gomog site.

Rick,
I fitted a heat shield over my Librands exhaust on my T16. I also replaced the air inlet pipe with heat resistant tubing as the original was burnt through underneath. I also put heat insulation on the wash bottle.


As Graham says this might get more reports if it is in the trad forum.

My apologies. I saw "Plus 4" and thought it was the correct place. I didn't know what CX generation meant. Now I do. I appreciate the feedback for this and the other suggestions.