OKZCC Technical Notes & Tips

PURPOSE
This bulletin contains cleaning procedures for valve lash adjusters. In many cases, cleaning valve lash adjusters can extend their service life. Mitsubishi Motors strongly suggests cleaning and inspecting lash adjusters before considering lash adjuster replacement. AFFECTED VEHICLES All models equipped with valve lash adjusters

PROCEDURE
Valve lash adjusters are precision mechanisms. Do not allow them to become contaminated by dirt or other foreign substances. Do not attempt to disassemble valve lash adjusters. Use only clean diesel fuel to clean valve lash adjusters.

1. Prepare three containers. Place enough diesel fuel into each container to cover a lash adjuster when it is standing upright.

2. Place the lash adjuster into container A and clean its outside surface, using a nylon brush if necessary.

3. While gently pushing down the internal steel ball using stiff wire (0.5 mm diameter), move the plunger through 5 to 10 strokes until it slides smoothly. This will remove dirty oil from the lash adjuster and loosen the plunger.

The steel ball spring is extremeIy weak. If the wire is pushed in with too much force, the lash adjuster will be damaged. If the plunger remains stiff or the mechanism appears to be abnormal, replace the lash adjuster.

4. Remove the lash adjuster from container A. Then gently push down the steel ball and push the plunger to remove the diesel fuel from its pressure chamber.

5. Place the lash adjuster in container B. Then gently push down the internal steel ball using stiff wire (0.5 mm diameter). Move the plunger through 5 to 10 strokes until it slides smoothly. This will clean the lash adjuster’s pressure chamber.

6. Remove the lash adjuster from container B. Then gently push down the steel ball and push the plunger to remove the diesel fuel from its pressure chamber.

7. Place the lash adjuster in container C. Then gently push down the internal steel ball using a stiff wire (0.5 mm). Do not use container C for cleaning. Foreign matter could enter the pressure chamber.

8. Stand the lash adjuster upright with its plunger at the top, then push the plunger downward firmly until it moves through its furthest possible stroke. Return the plunger slowly, then release the steel ball and allow the pressure chamber to fill with diesel fuel.

9. Remove the lash adjuster from container C and stand it upright with its plunger at the top. Push the plunger firmly and check that it does not move. If the lash adjuster contracts, repeat Steps 7 through 9 to fill it completely with diesel fuel. If it contracts again, replace it.

10. Stand the lash adjuster upright to prevent the diesel fuel from spilling out. Do not allow it to become contaminated by dirt or other foreign substances. Install it in the engine as soon as possible.

I could start this with a lot of boring stuff like "synthetic" is big molecules built up from small ones. Or, that polyalphaolefin (PAO) starts as a simple two-carbon molecule and is built up to a 10 carbon molecule.

However, I have been asked my opinion of synthetic vs. conventional oils, so I will just explain my view on this subject. My opinion does not go to the laboratory, but rather to the inside of the motor. Granted, the synthetics are more stable, flow at a lower temperature, and are less susceptible to oxidation. But I do not care for their use in older cars. These cars were built before the invention of synthetics and should remain on conventional oil and have that oil changed at regular intervals. The exception to this would be that racing motor you just built with new racing parts. Synthetics would work for these.

For new cars with all, or mostly all, aluminum motors I would use synthetics after a wear-in period, if the motor was started with conventional oil. If your motor was started with synthetic, I would definitely stay with it.

Is the benefit of synthetics worth the cost? In new cars, the answer would be yes. In older cars, you could go to a semi-synthetic and chang the oil at the regular interval.

Can you switch back and forth? Most all oil companies do not recommend mixing or switching back and forth. Synthetics are fully compatible with each other and with conventional oils. The early synthetics had high levels of ester. This did cause discoloration and thinning of the oil and in my opinion the loss of protection.

As to the question of the use of special oil filters or special disposal techniques for those who change their own oil. The answer is that you can use the same recommended oil filter and follow the same disposal procedures that you use with conventional oil.

Lastly, does synthetic oil produce horsepower? In every study or car and the dyno, the answer is yes. Less friction - less heat - produces horsepower.

There you have my opinion on this subject. If you are in a fully committed relationship with the car of your dreams, then step up and protect it, but don't overdo it. Just remember the by-product of the combustion engine is still there no matter what oil you use. So whatever you use - Change It!