Stripping and Rebuilding an M20 Cylinder Head - Revision history

PhilBeans: Clarification on rocker shaft scratches/gouges.

2014-10-24T08:48:21Z

Clarification on rocker shaft scratches/gouges.

PhilBeans: Added warning to check for shaft gouges/scratches before removal.

2014-10-24T08:23:32Z

Added warning to check for shaft gouges/scratches before removal.

Grrrmachine at 08:16, 11 May 2012

2012-05-11T08:16:51Z

Grrrmachine at 05:17, 23 September 2011

2011-09-23T05:17:47Z

Daved at 18:22, 25 November 2010

2010-11-25T18:22:10Z

Ugirylylov at 04:31, 24 November 2010

2010-11-24T04:31:17Z

Willnz: Protected "Stripping and Rebuilding an M20 Cylinder Head" [edit=autoconfirmed:move=autoconfirmed]

2010-05-13T05:46:04Z

Protected "Stripping and Rebuilding an M20 Cylinder Head" [edit=autoconfirmed:move=autoconfirmed]

Willnz: Reverted edits by 220.130.96.213 (Talk); changed back to last version by Hoshy

2010-05-13T05:45:48Z

Reverted edits by 220.130.96.213 (Talk); changed back to last version by Hoshy

220.130.96.213: 10

2010-05-11T10:54:14Z

Hoshy at 06:57, 15 July 2008

2008-07-15T06:57:29Z

@@ Line 37: / Line 37: @@
 The next part of the procedure is to remove the rockers and shafts.  I usually work with the pulley end of the head to my right.  Concentrate on removing one rocker shaft at a time.  We will be removing the exhaust side rocker shaft to begin with.  Place the pulley bolt back into the end of the camshaft so that you turn the camshaft.  Keep turning the bolt until it fully tightens.
-Before removing the rocker shafts, give them a careful going over for any nicks, gouges or scratches that might damage the shaft bores as you drive them out.
+Before removing the rocker shafts, give them a careful going over to check for any nicks, gouges or scratches that might damage the shaft bores as they are removed from the head.
 IMPORTANT NOTE: Remember that you will only be able to turn the camshaft in a clockwise direction from now on.  Attempts to turn in a counter clockwise direction will just remove the torx bolt.

←Older revision		Revision as of 08:23, 24 October 2014
Line 36:		Line 36:

	The next part of the procedure is to remove the rockers and shafts. I usually work with the pulley end of the head to my right. Concentrate on removing one rocker shaft at a time. We will be removing the exhaust side rocker shaft to begin with. Place the pulley bolt back into the end of the camshaft so that you turn the camshaft. Keep turning the bolt until it fully tightens.		The next part of the procedure is to remove the rockers and shafts. I usually work with the pulley end of the head to my right. Concentrate on removing one rocker shaft at a time. We will be removing the exhaust side rocker shaft to begin with. Place the pulley bolt back into the end of the camshaft so that you turn the camshaft. Keep turning the bolt until it fully tightens.
		+
		+	Before removing the rocker shafts, give them a careful going over for any nicks, gouges or scratches that might damage the shaft bores as you drive them out.

	IMPORTANT NOTE: Remember that you will only be able to turn the camshaft in a clockwise direction from now on. Attempts to turn in a counter clockwise direction will just remove the torx bolt.		IMPORTANT NOTE: Remember that you will only be able to turn the camshaft in a clockwise direction from now on. Attempts to turn in a counter clockwise direction will just remove the torx bolt.

@@ Line 130: / Line 130: @@
 [[Category: Technical]]
-[[Category: Maintenance]]
+[[Category: Repair]]
 [[Category: E30 Engines]]
 [[Category: M20]]

←Older revision		Revision as of 05:17, 23 September 2011
Line 128:		Line 128:

	Now is an ideal time to adjust your valve clearances, please see the tech article for the procedure for doing this. It makes life much easier to do this while the head is off the car.		Now is an ideal time to adjust your valve clearances, please see the tech article for the procedure for doing this. It makes life much easier to do this while the head is off the car.
−	[[Category:~~Servicing~~ ]]	+
		+	[[Category: Technical]]
		+	[[Category: Maintenance]]
		+	[[Category: E30 Engines]]
		+	[[Category: M20]]

@@ Line 1: / Line 1: @@
 In this guide, we will show you the correct procedure for stripping and rebuilding an M20 Cylinder Head.  This includes 2.0, 2.3, 2.5 litre engines.  For the benefit of the guide, we will be using an M20 2.5 head.
 *Required Tools
 *Female Torx Socket
-*Old Timing Belt
+*Old Timing Belt.
 *Lockable Grips
 *8mm Spanner
 *10mm Spanner
 *3mm Allen Key
-*11mm Deep 1/4&quot; Drive Socket
+*11mm Deep 1/4" Drive Socket
-*Short 1/4&quot; Drive Extension Bar
+*Short 1/4" Drive Extension Bar
 *Feeler Gauges
 *Valve Spring Compressor
-*Valve Grinding Stick &amp; Paste
+*Valve Grinding Stick & Paste
-*Suitable drift (1/2&quot; Drive Extension)
+*Suitable drift (1/2" Drive Extension)
 *Hammer
 *Magnetic Ended Screw Driver
@@ Line 53: / Line 45: @@
 [[Image:m20head-4.jpg]]
-Take a suitable drift, I found that a 1/2&quot; drive extension bar was the perfect size.  Use a hammer to knock the exhaust rocker shaft out from the right hand side of the cylinder head.  You only need to knock it a short distance, just enough so that you can slide the number 1 exhaust rocker from it's shaft.
+Take a suitable drift, I found that a 1/2" drive extension bar was the perfect size.  Use a hammer to knock the exhaust rocker shaft out from the right hand side of the cylinder head.  You only need to knock it a short distance, just enough so that you can slide the number 1 exhaust rocker from it's shaft.
 [[Image:m20head-5.JPG]]
@@ Line 97: / Line 89: @@
 Before you actually rebuild the head, it's a good idea to carry out a few routine checks and maintenance to check that the head is in good order.
-Firstly take the cylinder head to a machine shop and request that they check the tolerances of the valve guides (take your valves with you), check the face of the head for warps, have it pressure tested for cracks.  If all is okay then request for it to be &quot;chemically dipped&quot; and &quot;refaced&quot;.  A chemical dip removes all carbon deposits an generally cleans the head up to a new finish again.  You'll probably notice that your current cylinder head is stained brown.  A reface is where a very thin surface is removed from the face of the cylinder head giving you a nice smooth finish ready for you to mount your gasket against.
+Firstly take the cylinder head to a machine shop and request that they check the tolerances of the valve guides (take your valves with you), check the face of the head for warps, have it pressure tested for cracks.  If all is okay then request for it to be "chemically dipped" and "refaced".  A chemical dip removes all carbon deposits an generally cleans the head up to a new finish again.  You'll probably notice that your current cylinder head is stained brown.  A reface is where a very thin surface is removed from the face of the cylinder head giving you a nice smooth finish ready for you to mount your gasket against.
 When you get the head back from the machine shop you should re-grind the valve seats.  If you look around the rim of the valve where it contacts the head when it opens and closes, you will notice that it's most probably very shiny which is bad for a good seal.  Anyone can regrind valve faces but you will need a grinding kit which consists of grinding paste and a grinding stick.  These can be bought very cheaply from any motor factors.
@@ Line 113: / Line 105: @@
 [[Image:m20head-16.JPG]]
-It's important to install new Valve Stem Oil Seals before replacing the valves.  There is a special tool available for installing these seals but a deep 1/4&quot; Drive 11mm socket fits perfectly.  Begin by wetting the inside of the valve stem oil seal with some new oil to allow easier fitting.  Place the seal on the end of the 11mm socket and then use a firm force to push the seal into place making sure that you keep the seal straight.
+It's important to install new Valve Stem Oil Seals before replacing the valves.  There is a special tool available for installing these seals but a deep 1/4" Drive 11mm socket fits perfectly.  Begin by wetting the inside of the valve stem oil seal with some new oil to allow easier fitting.  Place the seal on the end of the 11mm socket and then use a firm force to push the seal into place making sure that you keep the seal straight.
 [[Image:m20head-17.JPG]]

←Older revision	Revision as of 05:46, 13 May 2010
(No difference)

@@ Line 18: / Line 18: @@
 *Spark Plug Wrench
-ETHQyh  <a href="http://ryftfyguyjkq.com/">ryftfyguyjkq</a>, [url=http://oxpwmwrktqug.com/]oxpwmwrktqug[/url], [link=http://tpefplsgmprs.com/]tpefplsgmprs[/link], http://azpfkoiilwur.com/
+==Stripping==
 ==Rebuilding==

←Older revision		Revision as of 06:57, 15 July 2008
Line 128:		Line 128:

	Now is an ideal time to adjust your valve clearances, please see the tech article for the procedure for doing this. It makes life much easier to do this while the head is off the car.		Now is an ideal time to adjust your valve clearances, please see the tech article for the procedure for doing this. It makes life much easier to do this while the head is off the car.
		+	[[Category:Servicing ]]