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Re: head bolt tension setting
These specs straight from service info
25Nm + 70deg+ 70deg+ 30deg
alot of after market gasket sets are the 25Nm and 3 lots of 60deg and the extra 10deg bolts are meant to be replaced (use once only) alot of bolts tend to start stretching when doing last 10 deg use oil on threads and washers under bolts 25 and 3 lots of 60deg is correct and more commonly used.
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Socket set and ratchet1: Drain the oil and coolant. Put on your eye protection and gloves and drain the oilfrom the vehicle.
Make sure the vehicle can not be started by removing the negative cable from the battery. Next the coolant will need to be drained so it does not leak when the head bolts are loosened. Step 2: Clean valve cover. Use some of the parts cleaner or brake cleaner to clean up the valve cover and as much of the cylinder head as is reasonable.Remove valve cover. If necessary, remove other components to make the valve covers accessible, and start removing the bolts from the valve cover.
Once all bolts are removed carefully removed the valve cover from the cylinder head. If any valve cover gasket material remains, remove it at this time and clean any excess oil from the edges. Set the valve cover aside carefully as it will be reused with a new gasket once repairs are completed.
Part 2 of 3: Pushrod engine head bolt removal
Head bolt socket (if needed)
Socket set and ratchetStep 1: Rocker arm and rocker removal. A pushrod engine has long pushrods that protrude through the cylinder head and attach to the rocker rail.
The rocket arm will need to be loosened first. Many manufactures have a specific sequence for removal of the rocker arm bolts. After the rocker arm is removed, the rockers will be unbolted.
Set all rocker arms aside in the order they were removed as they should go back to the cylinder they were removed from.Step 2: Remove the pushrods. Remove the pushrods one at a time from the cylinder head.
Put them into a numbered piece of cardboard as the pushrods will go back into the same slot they came from.Step 3: Loosen head bolts. Use the ratchet begin to break the cylinder head bolts loose.
Each bolt will be loosened but not removed. Loosen all of the bolts before removing any of the the bolts all the way. Step 4: Remove the bolts. Place each bolt through a numbered hole in the cardboard in case the head bolts are different lengths so they can be installed back into the proper hole.
The bolts may require a special socket depending on the manufacture. Step 5: Lift off the cylinder head. Once all bolts are removed, lift up on the cylinder headgently; the head should come free easilyIf the cylinder head sticks, lightly use a dead blow or rubber mallet to tap the cylinder head to be able to remove it. Set to the side in a safe area.
Warning: Cylinder head bolts have a specific sequence that is used when removing them. Consult the manufacturer's specifications for the proper removal sequence for the engine being worked on.
Part 3 of 3: Overhead cam head bolt removal
Socket set and ratchetStep 1: Remove the timing cover. The timing cover will need to be removed to gain access to the timing belt or chain.
This is necessary because the cam shaft sits in the cylinder head and is attached to the crankshaft with either a timing belt or timing chain. Step 2: Time the engine to remove the belt. The engine will need to be timed to avoid damage when the timing belt is removed.
Each engine is different and will have its own procedures to time. There should be marks on the camshaft and crankshaft that will be aligned to set the timing at top dead center (TDC)Step 3: Remove the timing belt. The timing belt tensioner will be removed or released to take the tension off the belt.
Once the belt is loosened, it should be able to be slipped of the camshaft in the cylinder head.Step 4: Remove the head bolts. Every engine will have its own procedures for the order that the head bolts are removed or tightened.
Loosen head bolts ¼ turn each in the order specified, which may require a special socket. Once all the bolts have been loosened they may be removed one at a time. The bolts must be organized or marked in case they are different lengths. Step 5: Remove the cylinder head. Once all the bolts are removed, the cylinder head may be removed from the engine. If it is stuck, tap lightly on the side of the head with a rubber hammer to loosen the cylinder head.
Warning: Most head bolts are torque-to-yield. These head bolts are single use only and once removed must be replaced. Torque-to-yield head bolts stretch when they are torqued to allow them to tighten properly and repeated application can cause the head bolt to break.
Removing the head bolts can seem like a daunting process
you could possibly get the tensions by going google and typing in--- head tension s for renault megane 2.0 l engine
torque settings in ft/lbs or newton meters is a by gone thing as the better method of stretching the bolts is to do it by angles
by using a torque wrench the bolt stretch ( tension) has variables like bolt thread finish, thread lubrication, bolts bottoming out from gunk/oil in the hole , uncalibrated tension wrenches , all of which means that not all head studs are pulled down to the correct stretch
By using angles , the head tension becomes uniform
May be a new head gasket but there has to be a reason for the leak
incorrect head bolt tensions, bolt holes full of oil or gunk preventing the bolts from tightening the head down, warped head ( head needs milling flat)
or corrosion holes in which case you will need a new head
Jul 22, 2015 - f77 2.8 diesel non turbo.1989 model.require head bolt tensions,stages and sequence please - Daihatsu Rocky question. ... Torque to yeild bolts need to be replaced whenever the head comes off.....Long bolts are 46 ft lbs. and ...
I am assuming that you have the 2.2L OHV engine (most do). If you have a timing chain problem, you may want to think about this....this engine is prone to timing chain tensioner breakage. This causes the timing chain to jump out of time. This will often cause the pistons to slam into the valves in the aluminum head, causing valve damage. If you decide to replace the timing set, insure that you get the chain, both gears, and a new tensioner. Install them and set the timing back to correct specs. THEN, perform a compression check of all cylinders BEFORE attempting to start the car. If there is uneven compression, you will need to pull the cylinder head and have it repaired or replaced before you can operate the vehicle. This is a tricky job. Aluminum heads are easy to warp and/or crack. You will need to replace all the cylinder head bolts when you replace the head as they are special bolts that are designed for one-time use as they have a stretch factor built into them. Remember to use thread sealant on those head bolts that extend into the water jacket or you will have coolant leakage. And most, important, USE A TORQUE WRENCH that is in good working order when tightening the head bolts. Be SURE to follow the correct pattern and torque settings or you will have problems.
it is good mechanical practice to replace all bolts that are operating under tension. That includes con rod bolts , big end bolts fly wheel bolts , head studs and crank shaft bolt. Some manuals recommend the replacement of cam shaft sprocket bolts as well. This practice is recommended where the engine is driven at high rpms. It is recommended practice because the tension effect actually twists the bolt and this combined with the tensional stress makes the bolts prone to failure. As it adds considerably to the cost many mechanics do not follow the practice but will charge for the new bolts as well.
Disconnect battery earth lead. Do not turn crankshaft or camshaft whn timing beld removed. Remove spark plugs to ease turning engine. Turn engine in normal direction of rotation (unless otherwise stated) Do not turn engine via camshaft or other sprockets. Observe all tightening torques. Remove engine, remve RH engine mounting. Remove auxiliary drive belts, water pump pulley, crankshaft pulley, timing belt upper cover, timing belt lower cover. Turn crankshaft clockwise to TDC on No. 1 cylinder, slacken tensioner bolts 5 & 6. Move tensioner away from belt and lightly tighten bolts. Remove timing belt. Remove water pump and replace with new one. Suggest to replace cambelt as well.
Ensure timing marks aligned3 & 4. Fit timing belt in anti-clockwise direction, standing at crankshaft sprocket. Ensure belt is taut between sprockets on non-tensioned side. Slacken tensioner bolt 5. slacken tensioner bolt 6. Allow tensioner to operate. Tighten tensioner bolt 6. Tighten tensioner bolt 5. Turn crankshaft on turn clockwise. Ensure crankshaft sprocket timing marks aligned 4.
Slacken tensioner bolt 5. Slacken tensioner bolt 6. Allow tensioner to operate. Tighten tensioner 6. Tighten torque: 20 - 26 Nm. Tighten tensioner bolt 5. tighten torque: 20 - 26 Nm. Apply thumb pressure to belt at middle. Approximately 5kg. Belt should deflect to 1/4 of tensioner bolt head width 7. Belt tention can also be set using burroghs (BT-33-73F) tension gauge 10 at middle. Turn crankshaft 90 ° anti clockwise. Check belt tension is 9.5 16,5kg (engine must be cold). Install components in reverse order of removal. Fit cranckshaft pully. Tighten crankshaft pully bolts 8. G4-J: Tightening torque: 12-15Nm.
G4-N/G4-k: Tightening torque: 10-12Nm
G4EA: Tighten crankshaft pully bolt 9. Tighten torque: 140-150Nm.
buy a new tensioner assembley and idler pully and might as well get a new belt while your at it. you will need a 3/8 ratchet a 15 mm socket and a 13 mm socket there is one bolt holding on tensioner remove it discard old tensioner put new tensioner in place and tight bolt. second remove bolt from idler pulley discard old pulley put inton place and tighen bolt. next install belt fallow belt routing digram put head of 3/8 rattachet into hole on tensioner or on bolt head of tensioner pulley depending on style of tensioner and pull or push to create slack in belt push belt into groves on all pulleys and release tensioner
Using a vise, lightly compress the secondary chain tensioner piston until the piston step is flush with the tensioner body. Using a pin or suitable tool, release ratchet pawl by pulling pawl back against spring force through access hole on side of tensioner. While continuing to hold pawl back, Push ratchet device to approximately 2 mm from the tensioner body. Install Special Tool 8514 lock pin into hole on front of tensioner. Slowly open vise to transfer piston spring force to lock pin (Resetting Secondary Chain Tensioners).
Position primary chain tensioner over oil pump and insert bolts into lower two holes on tensioner bracket. Tighten bolts to 28 N·m (250 in. lbs.).
CAUTION:Overtightening the tensioner arm torx® bolt can cause severe damage to the cylinder head. Tighten torx® bolt to specified torque only.
Install right side chain tensioner arm. Apply Mopar® Lock N, Seal to torx® bolt, tighten bolt to 17 N·m (150 in. lbs.).
NOTE:The silver bolts retain the guides to the cylinder heads and the black bolts retain the guides to the engine block.
Install the left side chain guide. Tighten the bolts to 28 N·m (250 in. lbs.).
CAUTION:Overtightening the tensioner arm torx® bolt can cause severe damage to the cylinder head. Tighten torx® bolt to specified torque only.
Install left side chain tensioner arm. Apply Mopar® Lock N, Seal to torx® bolt, tighten bolt to 17 N·m (150 in. lbs.).
Install the right side chain guide. Tighten the bolts to 28 N·m (250 in. lbs.).
Install both secondary chains onto the idler sprocket. Align two plated links on the secondary chains to be visible through the two lower openings on the idler sprocket (4 o'clock and 8 o'clock). Once the secondary timing chains are installed, position special tool 8515 to hold chains in place for installation (Installing Secondary Timing Chains on Idler Sprocket).
Align primary chain double plated links with the timing mark at 12 o'clock on the idler sprocket. Align the primary chain single plated link with the timing mark at 6 o'clock on the crankshaft sprocket (Timing Chain System).
Lubricate idler shaft and bushings with clean engine oil.
Install all chains, crankshaft sprocket, and idler sprocket as an assembly (Installing Idler Gear, Primary and Secondary Timing Chains). After guiding both secondary chains through the block and cylinder head openings, affix chains with a elastic strap or the equivalent, This will maintain tension on chains to aid in installation.
NOTE:It will be necessary to slightly rotate camshafts for sprocket installation.
Align left camshaft sprocket “L” dot to plated link on chain.
Align right camshaft sprocket “R” dot to plated link on chain.
CAUTION:Remove excess oil from the camshaft sprocket bolt. Failure to do so can result in over-torque of bolt resulting in bolt failure.
Remove Special Tool 8515, then attach both sprockets to camshafts. Remove excess oil from bolts, then Install sprocket bolts, but do not tighten at this time.
Verify that all plated links are aligned with the marks on all sprockets and the “V8” marks on camshaft sprockets are at the 12 o'clock position (Timing Chain System).
CAUTION:Ensure the plate between the left secondary chain tensioner and block is correctly installed.
Install both secondary chain tensioners. Tighten bolts to 28 N·m (250 in. lbs.).
NOTE:Left and right secondary chain tensioners are not common.
Before installing idler sprocket bolt, lubricate washer with oil, and tighten idler sprocket assembly retaining bolt to 34 N·m (25 ft. lbs.).
Remove all locking pins (3) from tensioners.
CAUTION:After pulling locking pins out of each tensioner, DO NOT manually extend the tensioner(s) ratchet. Doing so will over tension the chains, resulting in noise and/or high timing chain loads.
After installing all chains, it is recommended that the idler gear end play be checked (Measuring Idler Gear End Play). The end play must be within 0.10–0.25 mm (0.004–0.010 in.). If not within specification, the idler gear must be replaced.