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UAZ valve adjustment: processes

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UAZ valve adjustment: processes
UAZ valve adjustment: processes

Adjusting UAZ valves is a complex process that not all motorists can do. But, as practice shows, if you understand the operation once, then you can save time and money later. Correct valve adjustment will determine how well the power unit works.

The essence of the event

Reliability and engine life are very much dependent on valve adjustment. Despite the fact that the work of the UAZ plant is quite reliable, the adjustment of the UAZ valves should be carried out after every 5 thousand km or when the gaps between the rocker arms and valves change, which manifest themselves in valve knocking, a decrease in the performance of the power unit, “shooting” in the muffler etc.

UAZ valve adjustment

Technical nuances and adjustment procedure

According to the technical documentation provided by the Ulyanovsk Automobile Plant, the gaps should be: for the exhaust valves of cylinders No. 1 and No. 4 - 0.3-0.35 mm, for the remaining ones - 0.35-0.40 mm.

It is worth noting that the procedure for adjusting UAZ valvesproduced in accordance with the operation of the cylinders, namely 1-2-4-3. In this case, it does not matter whether the injection or carburetor is adjusted - the operations are similar. The action itself is performed when the engine is cold.

Required tools: a set of probes, a standard driver's tool kit. Upon completion of the operation, the valve cover gasket is replaced.

Methods for adjusting gaps

There are two methods that have been recognized by most auto repairers.

Method number 1: adjusting the valves of the UAZ engine according to the mark on the pulley.

Block head and valve mechanism of the UAZ engine

Used mainly when a "crooked starter" or crank is installed after various improvements. The procedure is as follows:

  1. Detection of the wire that goes from the distributor to the spark plug of cylinder No. 1. Visually fix the location of the slider at which the spark is applied.
  2. Removing the valve cover.
  3. Inspection of the KV pulley. According to the technical documentation, it should have three marks. If there are fewer of them, then make a guide to the last one - it must be combined with the pin on the block.
  4. Scrolling the HF with the crank until the marks are aligned.
  5. Inspection of the distributor slider. When it is located on cylinder No. 1, it can be concluded that the piston is placed at TDC, the valves themselves are closed, and they can be adjusted. If it turned out that the slider is located differently, this means that the valve adjustment can be started from cylinder No. 4. Procedurethe operation will be 4-3-1-2.
  6. Use a feeler gauge to set a gap of 0.35 mm. The probe should go in noticeably hard.
  7. After adjusting the cylinder, turn the pulley 180° and proceed to the next one.
  8. After the adjustment is completed, install the valve cover and start the engine.
Valve adjuster

Method number 2: adjusting the UAZ valves on the distributor.

It is worth noting that this method is used mainly by skilled craftsmen, but after some training you should be able to too.

  1. Visual fixation of the current ignition timing according to the scale on the distributor. Loosen the bolt by 10 on the scale and align the pointer with the 0 position.
  2. Repeat all subsequent actions specified in the first method. The difference is the emphasis not on the pulley, but on the position of the slider. This is explained by the fact that when the slider is aligned with the wire contact on the distributor, a spark will be supplied to the cylinder when the piston is at top dead center. This indicates that the valves are closed and the clearances are ready for adjustment.
  3. Adjusting the valves by turning the pulley and visually fixing the moment the slider closes the contact of the wire of the required cylinder.
  4. At the end of the adjustment, the lead angle is returned to its original position.

It is recommended to under-tighten the valves rather than over-tighten them. In the first case, only knocking or ringing is possible, and in the second case, the valve burns out, the head will also suffer damageblock.


Adjusting UAZ valves of any model is not difficult for either beginners or experts in the automotive business, so it can be done even in a home garage.

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