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One of my hydraulic lifters on camshaft is making a tapping noise as it's worn slightly and receiving a lack of oil when warming up.

Cars serviced well and full of fresh oil and there is no point in replacing the whole camshaft. However I've heard on old cars (16 yrs old) that oil/engine additives work well to prevent knocking and wear?

Anyone heard of slick 50 or if it's any good? Or in fact any other brand that could be recommended?

Cheers
 

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What engine oil are you using? Modern oil is very low on ZDDP in order to extend catalytic converter life. Some older hydraulic lifter designs can be sensitive to oil with reduced levels of ZDDP beyond what they were designed for.

My 1.0L Corsa B was originally designed to run on 15w40 API-SJ or 10w40 API-SJ oil. API-SJ oils typically contained 1200ppm ZDDP. API-SL under 1000ppm, API-SM under 800ppm. I use 10w40 Semi Synthetic API-SL in my Corsa and change it every 5,000 miles or six months whichever comes first.

ZDDP is the extreme pressure additive that stays in the oil film on components. It provides critical protection before adequate oil pressure is available. It decays very quickly in an internal combustion engine. As soon as the oil temperature exceeds 70 DegC it starts to break down. Most big flat tappet American engines need six monthly oil changes irrespective of mileage because of this. The protection ZDDP provides reduces steadily over time after just one heating over 70 DegC. An oil that had 1200ppm on day one may only be as effective as an 800ppm additive after six months. If you start off with an 800ppm oil then it will be far less effective in six months time.

Low ZDDP is not usually a problem on modern OHC engines, on flat tappet engines it's a disaster. I have a few flat tappet American engines and sourcing the right grade oil is tricky now. API-SJ is not easy to find. Millers and Morris still produce API-SJ oils but you have to phone their technical departments to check the ZDDP ppm as formulations change each year. Some companies dual mark API-SJ/SL.

I have used Slick50 back in the 80's. I believed their marketing messages and gave it a go. A few months after a strip down of my Mini's engine/gearbox revealed what is best described as 'grey cholesterol of the oil ways'. I cannot prove that clogged slick50 caused the oil starvation at the bearing but I haven't been willing to use it since. Some people love it, but I prefer to use the oil grade designed for the engine and change it regularly.

Expensive oil is not always the best choice. Cheap oils, even own brand supermarket oils can out perform the big name products if they are changed out before they have started to degrade. Sadly, most people don't do this and manufacturers rely on poor maintenace in order to sell new cars. That's my opinion following the extensive oil testing that I did while working in R&D for a previous employer.

Consider that the 1.0L 12v X10XE has 3 litres of engine oil capacity. It's designed consumption rate of API-SJ oil can be as much as 1 litre per 1,000 miles. So every weekly top up replenishes the decaying ZDDP in your sump. It's this regular replenishment that prevents the extreme pressure additives from becoming ineffective. By the time that the oil change is due at 5,000 miles, up to five fresh litres of oil have been added and consumed. The oil change is necessary to remove the corrosive acid and water vapour concentrations in the oil. The intervals are set for a reason.
 

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You can buy an hydraulic lifter additive that quietens them down. It worked in my 24v senator. It didnt work 100%,but it did make a difference. Worth a try.
 

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VIN..you seem to know your oils,whats your take on using a good quality car oil in a motorbike?? Is there that much diff in the make up ? I know they put friction modifiers in bike oil for the clutch,but surely the rest of the oil is similar?
 

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VIN..you seem to know your oils,whats your take on using a good quality car oil in a motorbike?? Is there that much diff in the make up ? I know they put friction modifiers in bike oil for the clutch,but surely the rest of the oil is similar?
The additive package and ash content is probably the biggest difference between two oils that are tested to perform within a recognised specification.

If an oil is sold as API-SM it will perform as any other oil sold as API-SM when it is fresh.

The differences between formulations become more apparent on extended drain intervals when degradation and contaminants are affecting the oil. If the engine is regularly pushed to it's operating limits OR regularly abused by frequent short journeys the oil will degrade quickly.

An oil blend with a high sulphated ash content (mostly cheaper oils) will sludge if the engine is used frequently on short journeys when the operating temperature and duration cannot completely evaporate the crankcase condensation. A premium synthetic blend will be less likely to sludge but ignore the extended drain intervals and change it regularly. If the vehicle manufacturer says 15,000 miles for normal use, consider oil changes at 7,500 for short journeys. If you use a high ash content oil and do short journeys, expect problems.

An engine that is used very hard will be fine on cheaper oil that is the correct specification as long as the engine is allowed to cool slowly with the oil pump circulating the oil.

If an engine is frequently shutdown hot, the oil will be damaged. If you can't let the engine cool to a normal operating temperature before shutdown then expect burnt on deposits wherever the heat cannot be dissipated. Turbochargers are particularly vulnerable to this, even modern water cooled varieties. They will all get burnt oil on the spindle bearings if shutdown hot. A synthetic oil will do better in this situation but it wont stop the damage. I've had one crankcase fire on the testbed with a premium oil brand that caught me by surprise when it got a little too hot.

My advice...
Check the oil level weekly and keep it at the upper level. Change the oil and filter regularly on or before the manufacturers interval and use the originally specified oil.

Some manufacturers change their oil recommendations as years go by but I doubt any of them do any testing to verify suitability. I know of one manufacturer that in the final year of production of an engine type, changed the oil spec for new vehicles with that engine because they no longer sold the correct oil themselves. They did this knowing that it was likely to cause longterm camshaft problems out of warranty!

I know some manufacturers now have two year intervals for oil changes. From my own experience with oil, I just cannot believe that this is good for any internal combustion engine no matter what oil it's supposed to use. Personally, I would never let an engine oil go beyond a year in service no matter what the oil or engine is made from as I can't see how a metallic engine can deal with the harmful build up of combustion gas acids and water vapour in the oil. My opinion is that extended drain intervals are something introduced by politicians and manufacturers to accelerate engine death in order to get rid of older vehicles and prevent new vehicles lasting more than ten years.
 
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