Could someone tell me what may happen if you dirve with no oil?. Oil pressure guage read 15lbs. Then the tappets started knocking. Added oil but engine doesn't sound the same anymore. What kind of internal damage could my engine have?

 

if it still runs..
is quiet..
and has good oil pressure then i would'nt worry about..

there is this yellow handled "thingie" under your hood that says "oil" on it..
you should look at it once in awhile..

...zap!

 

Scored bearings.

 

I didn't want to go into the whole story and I do know how to check oil. The engine stills runs rough. It's in a boat. Newly rebuilt and leaked oil. Mechanic told us that guage is mechanical and far from pump so it might read low and again not to worry. I just want to know what might be a problem now. Cracked block? Lifters? Valves? Tappets?. We just spent alot of money taking it out rebuilding it and installing it. I think we found leak. But what more could be wrong. Thanks so much

 

I didn't want to go into whole story. I do know how to check oil. This is a newly rebuilt in a boat. Mechanic told us guage was far from pump and could read low. Before we had time to check oil. (not the easiest thing) engine started making sounds. Added oil. Runs but rough. Just wanted to know what could happen. cracked block? valves? tappets? lifters?. Spent lots of money getting this done. Know where leak is. But what else could happen. thanks so much.

 

I know that a a sign of worn engine ( including bearings, cranke and rod, cam etc) is the oil pressure drops after the engine warms up also to do with the oil getting thin due to the heat ( normal) of an opperating engine.


Running the engine prolonged with low oil levels obliviously shortens the life of the engine. Not changing the oil also shortens the engines life.


I am sceptical of the mechanics theory the the distance of the guage will read low ( perhaps for only a feww seconds), his statement disregards fundamental physics.


No cracked block is caused from low oil. They would have checked the block prior to rebuild, unless they missed it.

the rest of the moving parts would have a little more than usual wear, not to serious, unless the rings started to screw up with the friction heat. I would try an compression test. If nothing seems to be working out, consider head removel for cylinder inspection. I had known crank bearings to spin and mess up when they are well worn or are the incorrect size and allow excessive clearance, is there any engine knocking, not to be confused with predetonation?

You say engine runs rough now? Did it start and run smooth and then started oil starving sounds?. If it is still running rough check the basics, ignition timming. plugs, fuel flow/pressure, water in the gass tank, fuel filter etc.
Does it have a computer and O2 sensors?


water in the gass tank when low caused me grief last Friday. Stalled the van in rush hour. Engine ran like a bag of hammers and then stalled repeatedly when restarted it felt that it was running on 5 of 8 cylinders.

 

I know it's in a boat, and I am guessing it's a revised automotive type engine. What engine is it? GM, Ford, Chrysler, cubic inches, No. of cylinders? I know what happens when you drive for 35 miles with a 400 cubic inch Ford pickup'78 or '79 with the oil light on because of low oil.

 

lifters = tappets
they are the same thing
-Patrick

 

Thanks I was wondering.

It doesnt always say "oil" sometimes it says "710"!


Parts that I would be most worried most about... crank, main bearings, rod bearings and cylinder walls. All of that would require you to pull the engine back out. Everything else is top end, just pop the heads off and redo them.

Luckily it's in a boat, I can pull my Merc v8 out of my boat in 45 mins. 2 bolts, 2nuts, one electrical plug, the fuel line, 4 hose clamps for the exhaust, lift, forward and out.

If it had 15 lbs on a mechinical gauge you are fine..... it only takes 10 lbs to run an engine.

Hope all works out for you!