The Automobile And American Life: A Short And Simple Essay On Sports Cars
The Automobile And American Life: A Short And Simple Essay On Sports Cars
I have in the past had great success using a wooden dowel, rather like the ones used on a valve grinding hand tool. Using contact adhesive stick a square of medium abrasive paper to the end of a flush cut dowel, allow the glue to dry then trim round with scissors. I personally have had great success using the Honda part as they seem to be made from a superior material and appear more compressible thus making a better seal against any slight face imperfections. This test head features my custom carbon steel hold down threads making it ideal for these hold down bolt torque experiments because data is not compromised by any aluminum thread deformation or failure. It has previously been reported that fresh hold down bolts have failed when several group members had torqued to 62 in/lbs and then 180 degrees (mistaking 1/2 turn for 90 degrees). Group members have noticed that Mercedes Benz has a published torque spec for the injector hold down bolts that seemingly differs significantly from the long standing DC published specs as shown in DC workshop manuals as well as on the instruction sheets that DC at one time included with replacement injectors.
Be sure you test your cyl head鈥檚 bolt hole threads by using a wire brushed used hold down bolt with an indexing paint mark, turning in by hand while counting turns, to assure threads are clean and bore is unobstructed to full depth. Try to rotate the unclamped injector, if it moves freely by hand then great, if it won鈥檛 budge try a little more force - but not too much. Tightening the fresh hold down bolt and seal ring will produce the same clamping force (defined by seal ring crush thickness) regardless of which of the 2 torque specs are used. The Sprinter鈥檚 copper seat seal ring features a double convex cross section and the clamping force induced 鈥榗rush鈥?creates narrow sealing flats on each side of the ring. Now the top tip, it will be necessary to purchase a new copper sealing washer. Chances are good you will find numerous versions that fit what you want out of a car, and much more. Don't mess with a good issue.
Check the gasket at the back plate/cover of the upper section of the inlet manifold as this is prone to squeezing out causing turbo boost leak and is this a good time to take a look/plan to rectify. If you have need to use a credit card then apply for a debit or check card tied to your bank account. Learning of credit score will help you uncover the best personal loan. Use a torch to inspect the injector seat in the cylinder head, it will likely be blackened and carbonised, this needs to be cleaned off and in severe cases re-cut to present a perfect sealing surface. The new ML will use the three-spoke steering that debuted on the new E-Klasse, as well as some of the buttons, such as the manual control panel for the infotainment system. While the actual MB recommended spec for tightening the hold down clamp bolt is 7Nm plus 90 degrees, plus 90 degrees - 7Nm plus 90 degrees will provide a safer torque to yield on a new bolt in an old head.
The extended threaded shank length, 85.83mm long, 6.0mm dia., 8.8 grade, factory hold down bolt, hold down pawl and injector seal ring are identical part numbers for both the 5 cyl. The best thing to do here is purchase a Honda part in preference to the genuine Mercedes Benz item. If your 6mm torx clamp bolt came away cleanly and without damage, discard the old one and purchase a new item from Mercedes. Remove the long single 6mm torx bolt that secures the injector clamp and place it safely to one side with the clamp itself. Inspect the threaded portion of the 6mm bolt if it is damaged or showing heavy signs of alloy material deposited on the threads then further action may be needed later on to rectify the threads in this failing all important tapped hole. In some cases the injector lifts out instantly, in others it can take hours of wiggling and fiddling, don鈥檛 be tempted to use hammers or heavy tools to do this job as commonly expensive damage results.
Each 90 degree rotation past 7 Nm with a new clamp bolt and clean hole results in a further 0.3mm stretch bolt yield, so my view has always been - softer composition, less crush and a little less beads of sweat on the final swing of the wrench! TRIAL 1- A fresh, factory hold down bolt torqued to 62 in/lbs (approx 7 Nm) and then an additional 90 degrees, results in 0.08mm crush of a fresh factory seal ring. TRIAL 2- A new seal ring and a fresh, factory hold down bolt torqued to 62 in/lbs. 0.08mm crush of the seal ring as well as a steady 180-190 in/lbs torque reading during angle tightening. Monitoring the bolt torque during the 90 degree rotation reveals a peak of 180-190 in/lbs before full 90 degrees is achieved and remains at this level all the way to 90 degrees. The desired residual bolt stress (to achieve essentially infinite cyclical fatigue life) is achieved by both specs but the 2X 90 spec does allow for less care and precision during the tightening procedure. The next part of the procedure is 鈥榤ake or break鈥?for the DIY repair and is the point of no return so please take heed.
I have in the past had great success using a wooden dowel, rather like the ones used on a valve grinding hand tool. Using contact adhesive stick a square of medium abrasive paper to the end of a flush cut dowel, allow the glue to dry then trim round with scissors. I personally have had great success using the Honda part as they seem to be made from a superior material and appear more compressible thus making a better seal against any slight face imperfections. This test head features my custom carbon steel hold down threads making it ideal for these hold down bolt torque experiments because data is not compromised by any aluminum thread deformation or failure. It has previously been reported that fresh hold down bolts have failed when several group members had torqued to 62 in/lbs and then 180 degrees (mistaking 1/2 turn for 90 degrees). Group members have noticed that Mercedes Benz has a published torque spec for the injector hold down bolts that seemingly differs significantly from the long standing DC published specs as shown in DC workshop manuals as well as on the instruction sheets that DC at one time included with replacement injectors.
Be sure you test your cyl head鈥檚 bolt hole threads by using a wire brushed used hold down bolt with an indexing paint mark, turning in by hand while counting turns, to assure threads are clean and bore is unobstructed to full depth. Try to rotate the unclamped injector, if it moves freely by hand then great, if it won鈥檛 budge try a little more force - but not too much. Tightening the fresh hold down bolt and seal ring will produce the same clamping force (defined by seal ring crush thickness) regardless of which of the 2 torque specs are used. The Sprinter鈥檚 copper seat seal ring features a double convex cross section and the clamping force induced 鈥榗rush鈥?creates narrow sealing flats on each side of the ring. Now the top tip, it will be necessary to purchase a new copper sealing washer. Chances are good you will find numerous versions that fit what you want out of a car, and much more. Don't mess with a good issue.
Check the gasket at the back plate/cover of the upper section of the inlet manifold as this is prone to squeezing out causing turbo boost leak and is this a good time to take a look/plan to rectify. If you have need to use a credit card then apply for a debit or check card tied to your bank account. Learning of credit score will help you uncover the best personal loan. Use a torch to inspect the injector seat in the cylinder head, it will likely be blackened and carbonised, this needs to be cleaned off and in severe cases re-cut to present a perfect sealing surface. The new ML will use the three-spoke steering that debuted on the new E-Klasse, as well as some of the buttons, such as the manual control panel for the infotainment system. While the actual MB recommended spec for tightening the hold down clamp bolt is 7Nm plus 90 degrees, plus 90 degrees - 7Nm plus 90 degrees will provide a safer torque to yield on a new bolt in an old head.
The extended threaded shank length, 85.83mm long, 6.0mm dia., 8.8 grade, factory hold down bolt, hold down pawl and injector seal ring are identical part numbers for both the 5 cyl. The best thing to do here is purchase a Honda part in preference to the genuine Mercedes Benz item. If your 6mm torx clamp bolt came away cleanly and without damage, discard the old one and purchase a new item from Mercedes. Remove the long single 6mm torx bolt that secures the injector clamp and place it safely to one side with the clamp itself. Inspect the threaded portion of the 6mm bolt if it is damaged or showing heavy signs of alloy material deposited on the threads then further action may be needed later on to rectify the threads in this failing all important tapped hole. In some cases the injector lifts out instantly, in others it can take hours of wiggling and fiddling, don鈥檛 be tempted to use hammers or heavy tools to do this job as commonly expensive damage results.
Each 90 degree rotation past 7 Nm with a new clamp bolt and clean hole results in a further 0.3mm stretch bolt yield, so my view has always been - softer composition, less crush and a little less beads of sweat on the final swing of the wrench! TRIAL 1- A fresh, factory hold down bolt torqued to 62 in/lbs (approx 7 Nm) and then an additional 90 degrees, results in 0.08mm crush of a fresh factory seal ring. TRIAL 2- A new seal ring and a fresh, factory hold down bolt torqued to 62 in/lbs. 0.08mm crush of the seal ring as well as a steady 180-190 in/lbs torque reading during angle tightening. Monitoring the bolt torque during the 90 degree rotation reveals a peak of 180-190 in/lbs before full 90 degrees is achieved and remains at this level all the way to 90 degrees. The desired residual bolt stress (to achieve essentially infinite cyclical fatigue life) is achieved by both specs but the 2X 90 spec does allow for less care and precision during the tightening procedure. The next part of the procedure is 鈥榤ake or break鈥?for the DIY repair and is the point of no return so please take heed.
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