93 ford probe GT, KL-DE 2.5 L V6, I was cruising down the expressway and I noticed that my oil pressure was low, about 25 psi (i installed an aftermarket mechanical gauge) it is usually about 45 psi, so I pulled over and checked the oil it was fine, not low at all. Well when I took off it was knocking at about 2000 rpm, I drove about another 4 miles and the motor locked up, now my question is can I rebuild this motor if it has thrown a rod or crank bearing. Could I just remove the old bearings and put new ones in there as well as piston rings and a hone, and it would run fine or is there more involved in rebuiling a siezed motor. I am a mechanic working for a local repair shop so I have the knowlege on rebuilding I just dont know if I can rebuild this or not. Thank you mike
If you have thrown a rod, chances are it is not expedient to re-ring the motor. Throwing a rod is akin to chucking a large piece of granite into the moving mass of the crank, rods, pistons, etc. It destroys everything it touches, often punching a hole (or several) in the engine block itself making it impossible to salvage. I think the worst i've seen that can undergo a rebuild and still be ok, is a spun bearing or a rod knock that was caught early enough not to elongate the rod by too much. By what you've said, it sounds like could possibly need a reman'ed engine.
If your motor, for example, stopped simply because the bearings melted, (due to inadequate oil) the engine would be rebuildable, however you would most likely need to replace every moving part on the short block (and possibly a few things on the heads as well) have the block hot tanked, checked, double checked and line bored. Then you could be sure it would be last for another 150,000 miles.
I hope this doesn't discourage you. Rebuilding a motor, you being a mechanic will know, is a time consuming, expensive job which i'm sure you will not want to do only ten miles down the road after you've done it the first time. I hope this helps.
February, 20, 2007 AT 6:56 PM
Oops. Re-reading my post I realize I sound pretty pessimistic. You should definately see what can be done with motor. Maybe it only needs a minimal amount of work.
February, 20, 2007 AT 8:11 PM
If you had low enigine oil pressure. This means you have worn out cam bearings strike 1 if motor locked that means that a bearing has siezed to the crankshaft and that is not good. That means a new rod cause it had to of got real hot plus the crank is trashed and so are the mains strike 2 If I were you. For the year of the car and you didn't state the mileage on it. I would just price a crank kit and one rod and see if I would want to repair this car it might scare you. NOS : roll: