Hydraulic tappets — checking and bleeding air (Mitsubishi Pajero 1)

The hydraulic tappets are manufactured with high precision, and dust and dirt are not allowed to get on them.

Fixing the hydraulic tappet with a bracket during installation

Hydraulic pusher device

3.5L engines

Removal

1. Press the valve spring.





2. Remove the rocker arm.

3. Remove the hydraulic lifter.

4. Replace the pusher and install the parts in reverse order.

Checking without removing from the vehicle

Checked tappets at TDC on 4-cylinder engines and diesel

Checking the tappets on a 12-valve 3.0L engine

Checking the tappets on a 3.0L 24-valve engine

Checking the tappets on a 3.5L engine

(The article is based on data from the website: «mitsubishiman.ru»)

Checking the rocker arm swing on the hydraulic tappet (except 3.5L engines)

If the tappets make loud knocks after starting the engine, or if there is a persistent knocking sound that accompanies engine operation, do the following.



1. Check the oil level and condition, change the oil if necessary. This is due to the fact that knocking can be caused by air that has entered the tappet channels due to a significant violation of the oil level or its foaming.

2. Air can be removed from the tappets by repeated slow (within 30 sec) increasing the speed to 3000 rpm (the knocking should gradually disappear).

Avoid leaving your car parked for long periods of time with the engine off, or parking on slopes.

3. If you cannot remove the air using the above method, do the following: (on all engines):

• set the piston of the 1st cylinder to TDC of the compression stroke;
• press on the rocker arms indicated by the light arrow, selecting the play between the valve end;
• turn the crankshaft 360° and press on the rocker arms indicated by the dark arrow, removing the play between the valve end;
• press the rocker arms in the area just above the pushrod. If there is any play in the tappet, replace the tappet, remove the air from it, and repeat the check. There should be no play felt when rocking the rocker arm.

If there is no play in the tappets, the knock is caused by another reason.

Removal air

1. Immerse the plunger in clean diesel fuel.

2. Press the wire 4-5 times on the ball to remove air.

3. Press the plunger. If you feel a lot of resistance, the pusher is in good condition, otherwise repeat the bleeding. If the air cannot be removed, replace the plunger. When finished, store the plunger in the working position.

4. Check the hydraulic tappet for leaks using the MD998440 device. To do this, measure the time required for the plunger to move 1 mm, starting from its displacement of 0.2–0.5 mm.

This time should be 4-20 sec. Otherwise, replace the hydraulic tappet.