Features

How to fix a Td5 warped exhaust - pictures

by: Auto Express team

27 Sep 2017

Removing the manifold: The acoustic cover has been removed from the top of the engine by removing the three bolts, as has the trim over the top of the radiator and fan.
The air intake hose to the turbo charger is also removed by loosening the jubilee clip and unclipping from the air cleaner at the opposite end.
The tell-tale sooty deposits on this engine are found at the rear, where one stud has been pulled out of the cylinder head, with the threads ripped out.
Remove the nuts holding the manifold in place, using a 13 mm socket wrench. Some are difficult to get at and require a small spanner.
With air conditioning, the drive belt is removed and the AC compressor unbolted and moved to one side. No need to break the refrigerant circuit.
The turbocharger is unbolted from the exhaust manifold and eased left still attached to the exhaust downpipe, there’s sufficient flex to move it.
The exhaust manifold can be now eased off of the remaining studs and withdrawn carefully from the engine, holding the turbo clear all the while.
The old gasket is removed, note its condition. The gasket has split, and the material around the broken stud has disintegrated.
On this engine, all studs are being replaced. This quick method of removal involves welding the nut on each stud and turning it with a spanner.
Now that all studs have been removed, the mating surface on the cylinder head is carefully cleaned up using a solvent and fine emery paper.
The old manifold (bottom of picture) shows the soot staining around the rear port where the gap had opened up. The new manifold is seen above.
Fitting the new manifold: As the rear stud has been ripped from the cylinder head, an M10 stud will be fitted, so the hole is enlarged to 9 mm in preparation for re-threading.
The M10 tap is being turned into the hole using self-gripping pliers, as the space is too restrictive to use the full threading tool.
Two nuts are tightened together on the new stud to lock them so the stud can be tightened into the head. This is an alternative removal method, too.
The oversize M10 stud has been threaded into the cylinder and is ready to be tightened using a 17 mm spanner, before the nuts are removed.
In the remaining undamaged threaded holes, extra long M8 studs are fitted from the special Alive Tuning Uprated Td5 manifold stud kit.
Replacement manifold is having one hole drilled out to 10 mm to accommodate larger stud. Corresponding hole in manifold gasket is also enlarged.
The exhaust manifold is trial fitted to the studs to check that the enlarged hole is sufficient and that the other new extended studs are in alignment.
The new exhaust manifold gasket is placed over the studs on the cleaned and prepared cylinder head first. Note the thicker shorter M10 stud to the rear.
The replacement exhaust manifold is gently tapped home squarely over the new manifold studs and is nearly ready to be bolted down.
These spacer bushes, fitted between the manifold and the securing nut, allow for greater flexibility under expansion, giving a more reliable seal.
This cut down 13mm spanner is a great aid in getting the nuts turned onto the studs in some of the most restricted places at the cylinder head.
The nuts are tightened down progressively, working from the centre outwards in stages in order to achieve and even progressive clamping.
The Aerotight lock nuts that come in the Alive Tuning stud kit provide a firm secure fixing over the expansion bushes and look excellent.
That’s the manifold sorted. We’re now ready to refit the turbocharger and other components to complete the job.