Why does the exhaust get very hot - 2008 Scion Xd

valve clearances sohc 4g63 carb motor both hot and cold

Valve clearance - INLET mm: 0,15 hot
Valve clearance - EXHAUST mm: 0,25 hot
This engine is set hot if you are repairing the engine and have to do this cold
then set to 0.10mm INLET and 0.20mm EXHAUST
Then once hot readjust to specs

.010"inlet hot and .012" exhaust hot for water cooled engines and .012" inlet hot and .014" exhaust hot for air cooled engines

Cold: Intake 0.30mm, Exhaust 0.50mm.
Hot: Intake 0.20mm, Exhaust 0.040mm.

The 2L Toyota engine runs an overhead cam with bucket lifters, and requires removing and replacing of shims to adjust clearances...

There is raw fuel entering the exhaust system or the exhaust is plugged

a engine model would be good
petrol
generally .010" hot inlet
.012" hot exhaust
diesel
.012" hot inlet
.014" exhaust hot.

Not RED hot, no.
You may have a restriction or a timing problem.
Was it that hot before you replaced the exhaust parts ?

The exhaust manifold is going to get hot, this is where the engines exhaust flows through. these tempertures reach high temps,

If the manifold is glowing hot then theres a problem.

Sometimes people say the manifolds are getting to hot because they see them smoking. The reason on most of these cases is due to a leak, aleak from a bad gasket like a valve cover gasket. Engine oil leaks down on to the exhaust manifold causing smoke. make sure there are no leaks .


A few reasons that would cause exhaust manifold to heat up more than normal would be a engine thats running rich, this may be due to a leaking injector or a poor running engine. Another reason may be that you have a plugged cat. converter.

The Exhaust manifolds can reach about 600 degrees, the last thing is people hear the metal expand or contract and think there are getting to hot , this is normal.

Please let me know if there is something else i can help you with. thank you and have a good day.

your converter is blocked needs to be changed,unless exhaust system is damaged and causing restrition.

Sounds like the catilitic converter is plugged.

Make sure that your catalytic converter and exhaust is not plugged..Also check for propper map sensor operation,the reading that the map sensor supplies to the pcm is used to adjust ignition timing and fuel delivery.If the timing is being retarded to far , the exhaust exiting the cylinders will be extremly hot and will produce the effect you are having...Good Luck...