[Cornish_Blue]

Hello, I thought I would investigate an engine bay undertray upgrade as with the inclement weather we have in blighty and the cost of a new gearbox as the current cover does not protect the box.

The current standard undertray covers the engine sump but not the exhaust or gearbox. I am unsure why not as it's always been covered on all of my extended families vehicles made post 2000.

Anyway, I ordered a copy of the A Class undertray - part number is A2465200123. The genuine infiniti one is just the same I believe.

Example - google - MERCEDES-BENZ A-CLASS W176 Engine Undertray Cover A2465200123

The one I ordered is made from HDPE which is more heat resilient and not prone to cracking. I needed 4x MB undertray frame clips and five extra screws along with two cable ties. I also fitted Aluminium exhaust heat tape to below the exhaust and fitted rubber door seal to the outer edges of the tray for better weather protection. My choice of cover is a moulded copy of the Mercedes tray, it is not as precise the hard plastic one and needed a small amount of fettling to get it to fit perfectly.

My tray is secured by three front clips, three mid clips, two rear clips and two cable ties from the tray to the fixings near the suspension lower arms.

Total cost around £65.


Very pleased and highly recommended 🖐

 

[Bartos]

I had this cover, but I quickly dismantled it. Don't use it. In summer, the engine compartment gets very hot, the air filter housing is hot. Engine and transmission are not cooling properly.

This cover was on diesel engines.

 

[Cornish_Blue]

I appreciate the information, I will make a note that it is not required in summer in hot climates. What ambient temperature was the weather when you experienced issues?
The gearbox oil is cooled via an oil / water heat exchanger under the airbox. I would not expect any issues at all normally. If my temps on the dash were going up I would expect the radiator fan and electronic water pump to increase flow to aid cooling.
I have ambient temps of below 10'c winter and 25'c tops in summer. 🖐

 

[Bartos]

I understand you. I also have about 25 ° C in the summer.
I watched what was happening in the engine compartment in the summer. You can even check with your hand. The engine hood is hot, the air filter housing is hot, so the engine does not get chilled air in summer and its power drops. High temperature in the engine compartment negatively affects all sensors, hoses and cables that have become damaged over time. Likewise, the engine block, without cooling from the bottom, maintains a higher temperature, which negatively affects the seals.

As for the gearbox, at a very high temperature it worked with a noticeable gear change, it jerked slightly.

The coolers cool down the fluids in the engine and gearbox, but not the accessories that work with them.

Mercedes thought about the situation. Therefore, gasoline engines and AMG versions do not have a hood under the engine. While driving, the rush of air is designed to cool the oil pan of the engine and gearbox, additionally ventilates the engine compartment and cools the intake system.

 

[Cornish_Blue]

Thankyou. I will pay close attention to temps as you advised, best not to overcook anything as you and I both understand. I think I will remove large cover and fit smaller one May to September months. 👍