3.4.25. Valves and springs

Compression of springs at installation of the valve

The additional valve on Mitsubishi engines

On Mitsubishi engines of early releases the additional valve blocking the jet screwed in the combustion chamber and intended for formation of a stream of the gas mixture directed to a candle to improve fuel combustion is provided.

When dismantling a head of cylinders these valves should be removed first of all. Adaptation MD 998310 is for this purpose used.

At a jet valve reversing adaptation cannot be inclined as cores of additional valves can be bent.


1. When dismantling squeeze a spring of the first valve by means of suitable adaptation and remove crackers.

2. Release a valve spring, remove a plate springs, a spring and a basic washer.

3. Get the valve and remove an oil scraper cap. Remove a deposit from valves.


Places of check of wear of the valve

And – places of check of wear of the valve in an end face;
In – places of check of width of a corbel

Check of diameter of a core of the valve

Check of curvature of a core rolling

Check of vertical position of a spring

Check of length of a spring

Width of a corbel of a head of the valve and landing corbel

1. Valve head corbel
2. Landing corbel

Attentively examine valves, check existence on facets of valves of cracks, traces of uneven development, ablation of metal and a progar. At detection of development about an entrance to the directing plug, ovality of end faces and reduction of width of a corbel against norms replace the valve.
Check length of springs and vertical position of springs (the deviation from a vertical no more than 2 ° is allowed). Replace springs with shrinkage.

Check a gap of valves in plugs or on a difference of diameters of a core and the plug, or having shaken the valve in the plug. If the gap exceeds norm, then the valve (or the plug) replace.

Define situation and width of a landing corbel, having greased a saddle with paint on a metal basis and having installed the corresponding valve. If a corbel continuous, then the valve and a saddle it is possible to use and further. If a trace faltering, then it is necessary to proshlifovat the valve and a saddle and to grind in the valve to a saddle.


Additional valve of a jet

1. Washer
2. Plate
3. Spring
4. Jet
5. Oil scraper cap
6. Ring
7. Case
8. Head of cylinders
9. Jet nozzles

Dismantling of the valve

For dismantling of the valve squeeze a spring, turn off a nut and remove crackers the Worn-out additional valve changes assembled. For definition of its state the valve can be disassembled (adaptation is required). If details in satisfactory condition, then replace only an oil scraper cap of the valve.

Replacement oil scraper cap of the additional valve

1. Cap
2. Case

After dismantling check wear of a core of the valve, at detection of traces of a burn-out and strong wear (is defined by rolling) assembled replace the valve. Collect the valve upside-down.

The additional valve of a jet before installation

1. New ring
2. To grease

At installation tighten the valve with m 18–20 N.' moment.

Assembly of the valvate mechanism
Napressovka of a cap

Assembly is carried out upside-down. Carefully remove the remains of pritirochny material and wash out. Grease cores and a napressuyta new caps. Establish all removed details on former places.