Rod knock

oil

#1

My 17 year old grandson let the oil get too low in his '99 Saturn, now he had a loud knock for about 4 seconds when he starts it. One mechanic said possibly a rod knocking. Is it still O.K. to drive it ?

Only has 62,000 miles on it, and it doesn’t leak oil onto the driveway. Are we headed for a new engine ?


#2

That’s probably a bearing knock, perhaps a spun bearing. The mechanic was probably thinking connecting rod bearing.

A '99 Saturn? Keep driving it. It’ll cost more to repair than it’s worth. It may just run forever like that.


#3

First of all, how low is “too low?” Was the oil pressure warning light on?

If the rod bearings, or the main bearings, or damaged, you can still drive, but doing so will only make it worse. Eventually the bearings will give out and K-BOOM. A rod through the block is not a pretty thing.

“One mechanic said . . .” How many mechanics have you consulted, and what did the others say?


#4

By the way, I remember doing almost exactly the same thing when I was 17. It was an expensive lesson, but it taught me the value of periodically checking the oil level and changing the oil at regular intervals. I’ve haven’t had another oil-related engine problem in the 39 years since.


#5

I agree that this vehicle is probably not worth repairing, but if you do decide to repair it, it is very important that the 17 yr. old pay for the repair.

If an adolescent does not have an economic stake in something, he/she does not usually take very good care of it. Making him pay for the repair would help to teach him the importance of responsibility for valuable possessions and the importance of basic periodic fluid checks and maintenance. If he doesn’t have the money currently, be sure that he gets a job and then devotes a lion’s share of the salary to paying for the repair.


#6

Too low was “didn’t show on the dipstick”. The oil light had blicked a few times, and he had told his mother " widow ", and she put off checking the oil. Says if it was all that bad, the light should have stayed on. Consulted only one mechanic so far. And the answers I have gotten here are very helpful.


#7

“Says if it was all that bad, the light should have stayed on.”

I’m not sure if his mother or the young man made that very foolish pronouncement, but…in addition to making the young man pay for the repair of his car, I would suggest that you pay to send him to a Basic Auto Maintenance course. This is usually available–at very low cost–in the evening–at your local vocational school, through their Community Education or Continuing Education program.

A course like that could prevent him from destroying the engine, or the transmission, or…of his next car.


#8

If you’re feeling brave you can drop the oil pan and change the big end bearings in situ, you won’t be able to do anything with the mains though.

I haven’t encountered this particular ‘challenge’ on a Saturn, but it looks doable.


#9

I hope you will take the time to explain to both your grandson and his mother that the oil light does not indicate low oil level, it indicates low oil PRESSURE. Once the light stays on the engine is probably toast. A flickering oil pressure warning light is a warning of impending disaster, and should never be ignored.


#10

I shall take your suggestion under advisement. Him and his 14 yr. old brother. Thanks for the suggestion.


#11

Keep driving it till it dies. A 17 year old and car is not a long term relationship typically.


#12

A '99 Saturn cannot be expected to have a long term relationship with ANYBODY, no matter their age.