Overfilled oil - now engine broke

[danp1800]

1963 P1800 B18 engine

I took my car for a service, I don't normally bother. They say they only changed the oil.

When I got it back the engine didn't sound right. A few weeks later knocking appeared. Knocking was louder at low revs and quiter at high speed and revs.

Anyway I was on a journey and hoped to get home but knocking got louder and louder and then the engine stopped! It wont restart.

I checked the oil and they had overfilled it by about a cm.

Obviously (despite being able to do this one thing correctly) they claim that this cant be responsible for engine malfunction.

Admittedly we don't know the cause yet, but it's definitely something they did. Had the car 15 years and first time engine has malfunctioned.

Thanks in advance for help.

[dellow]

Could be a faulty or incorrect oil filter?

[dingov70]

Exces oil is very unlikely to make an engine rattle its self to death , unless it was a diesel that breathed it ALL in .

Normally a petrol engine will expel the oil as froth or by forcing a seal / gasket to leak .


A possible scenario is the use of a high detergent oil in an engine that has not been regularly serviced , this washes away any carbon / gunge / whatever that was acting as a seal . The result :- oil escapes from the side of bearings rather than supporting them & chaos results .

I know seen it done many times by well meaning customers knowing best

[Volvo_133]

My opinion is 1 cm above maximum on the dipstick would not cause major catastrophe to the engine bearings. The seals would not appreciate it.
I would ask for confirmation of oil grade used.

[classicswede]

I would check the oil for petrol content. Its possible it has started running very rich and petrol has been diluting the oil and causing it to be overfull

[Waddii]

I'd check the valves are moving (through the oil fiiler cap on the rocker cover) as you turn the engine over(by hand or starter). Could be timing gear failure. Just a thought as knocking at low revs getting worse then engine won't start/run fits the description at least.

[Volvorama]

Does sound like it could be a timing gear failure. Another quick check is to pop the distributor cap off and see if the rotor arm still rotates. This is driven off the camshaft of course.
Gear failure unlikely to have been caused by the oil change unless some dislodged dirt has clogged up the oil sprayer for the gears. Simple enough job to replace gears and the oil sprayer can be checked at the same time.

[omc 47]

Originally Posted by Volvorama

Does sound like it could be a timing gear failure. Another quick check is to pop the distributor cap off and see if the rotor arm still rotates. This is driven off the camshaft of course.
Gear failure unlikely to have been caused by the oil change unless some dislodged dirt has clogged up the oil sprayer for the gears. Simple enough job to replace gears and the oil sprayer can be checked at the same time.

Timing gear failure gets my vote too.......went from Evesham to Weston Super Mare (90 miles) once and when got to WSM heard this awfull knock on tickover but went away on revs.
Started out back home and 85 miles into journey timing was getting so bad engine would knock misfire and spit back etc BUT she got us home .Upon inspection the fibre gear had completely seperated from the centre boss and is a common problem but not serious with no other damage or issues. Front cover off will reveal the gremlins no doubt but change the oil and filter again after repair due to contaminents from the damaged gear........good luck.

[CLIVERALLY]

Ok will wade in here, As a mechanic of some 45+ years and having owned my own car repair and mechanical business.
Overfilling modern engines with oil particularly diesels will cause terrible damage (diesels will hydraulic..in other words wont stop even tho key is out). Aswill the wrong type of oil. destroy modern petrol engines

Older engines such as the B18/B20 will generally throw it out of the breather system or out of the filler cap and make a mess. The situation is not ideal and oil leaks will spring at various points if driven at speed or high pressure BUT catastrophic damage in my experience would not occur due to overfill. If the oil has been overfilled this is a schoolboy error and not what should happen in a professional set up..unless and apprentice did it!!...its also a waste of oil !!!
Knocking at low revs and tick over... would not I feel be a result.
Sadly as any mechanic will tell you without seeing the car first hand everyone will be guessing..sorry