With the stated milage there is just a lot of wear and tear. A thrown rod depending on how it actually looks can just be a quiet car suicide. I have had a rocker arm break at 56k for no reason aside from a possible manufacture defect. At 160k those parts have been hammered for a good long time. The car will start and run just fine until the piece just lets go. If the part shows a bearing failure at that age it is not a big surprise, except to you.
I’m not a mechanic, but is it possible that an injector on the cylinder that threw a rod was flooding the cylinder with too much raw fuel and causing a hydraulic lock? The fact that the car wanted to die when it got up to about 50 mph indicates that it might not have had too much fuel injected into at least one cylinder. When you boosted the battery, the starter had more power, tried to compress an uncompressible liquid and the rod was forced through the pan.
I’ve tipped a lawnmower on the side with the carburetor on top. Raw fuel ran into the cylinder and I couldn’t turn the engine over. I removed the spark plug and pulled the cord. That forced the fuel out of the cylinder and when I replaced the plug, the engine fired right up. That is the rationale behind my guess as to the cause of your problem.
Well, thanks a lot everyone for all the info. I actually learned quite a bit. You guys are pretty knowledgeable
It seems suspicious to me too, but reading back, it seems that you never check your oil level between changes and when you did have the oil changed, it was very dirty and probably low. It seems that you are a reactive buyer of car services rather than a proactive one. When something goes wrong, you want to repair just that thing and ignore all of the things you need to do to keep the car healthy.
Since you will now need a newer car, take the proactive approach. Change the fluids at the recommended cycles. Fix anything that goes wrong otherwise immediately. Find a good mechanic and give him or her your business. You will spend less in the long run.
What were the conditions (meaning how fast were you going and were you shifting gears) whe the rod came through the pan? Rod comming through the pan is odd, through the side of the block is more like it. If a piston broke and allowed the small end of the rod to move around there would be damage but not out of the pan. Now if a connecting rod cap bolt(s) broke we would be getting closer to internal engine parts comming out the pan.
I do see you say the rod came out the pan under cranking conditions, but this is way hard to believe. I have seen engines with no bearing material left but the rod was still connected to the crank. On the other hand I have seen rod cap bolts break (conincidently on a FORD but a V-8). All this did was make a little noise till it was fixed.
A 160k miles car with an existing engine noise and the hood not coming up for 2000 miles to check the oil gives the mechanic a free pass in my opinion.
It could be that noise was an excessively worn rod bearing due to miles and a low oil level. At some point (as in startup with little to no oil pressure to hold the bearing shells) there may be enough wear for one of the rod bearing shells to move to the opposite side and join the other half. When this happens it’s either boom or screeching halt.
I hope you didn’t have 30w oil in the engine, unless you live in Florida.
What were the circumstances when the motor blew up? How fast were you going? Is the car an automatic or manual? Did you shift into the wrong gear? If you change oil every 3000 miles and check the level on a regular basis,it should not be black. Did the motor ever overheat?
No mechanic wants an engine job. They are a time and money loser.
In the 70’s my side of a VW overhaul was $100.00 and my rent was 90.00. As soon as I had my first overhaul in the bank I knew I had my rent for the month
Or 10W-30.
I’ve seen bearings go at 140k.
It is very difficult to understand how an engine could throw a rod out on start up unless the throttle was near wide open regardless how poorly prior service had been and even if there was no oil whatsoever in the engine. A normal startup with no oil pressure would result in loud knocking and if the engine was not shut off it would likely begin to seize. With hydraulic lifters it would certainly begin to falter and soon stall. But with at idle rpm it should not throw a rod. I have seen engines pushed to start that bent connecting rods and broke pistons but never throw a rod. I have only seen rods thrown when high rps were involved.