Whats goin on.Wondering if anyone has some helpful insight on my 93 240. Took it to my auto class to check out what is causing the leak. My instuctor said it looks to be a Main Crankshaft Seal. Does anyone have any idea on how much that is gonna be to fix. Just did an oil change and upgraded to 20W50 synthetic oil to slow down the dripping. thanks in advance

This has happened to every 240 I have ever owned and to every friend I know that has one (assuming that it is leaking from the front. If not, then it is a different problem). So if it is leaking from the front, its an easy fix. Under $10. Go to Autozone or a parts store and pick up a front crank seal. Make sure its the front. Sometimes in their computer it may be listed as timing cover seal. Take off your belts. Then use an impact to loosen the big bolt on the crank pulley (harmonic balancer). Then pull it off and behind that is your front crank seal. Pry the old one out with something. Then put the new one in, dust seal lip facing outward. But use something flat to push it in evenly. Then re-assemble. It's actually a really easy job and should definately fix your problem. Oh, and after your done, change your oil back to normal because I doubt your engine is liking that thick ass oil. Change the filter too. Hope this helps.

mine is leaking to the point that 9 months of hard driving got enough oil on the belts to make them slip and squeal at high rpm. so i guess im lucky if its only that bad.

This has happened to every 240 I have ever owned and to every friend I know that has one (assuming that it is leaking from the front. If not, then it is a different problem). So if it is leaking from the front, its an easy fix. Under $10. Go to Autozone or a parts store and pick up a front crank seal. Make sure its the front. Sometimes in their computer it may be listed as timing cover seal. Take off your belts. Then use an impact to loosen the big bolt on the crank pulley (harmonic balancer). Then pull it off and behind that is your front crank seal. Pry the old one out with something. Then put the new one in, dust seal lip facing outward. But use something flat to push it in evenly. Then re-assemble. It's actually a really easy job and should definately fix your problem. Oh, and after your done, change your oil back to normal because I doubt your engine is liking that thick ass oil. Change the filter too. Hope this helps.

That is deffinately news i wanted to hear. Also thanks for the pretty simple walk through. Ya, I didn't want to add thick oil, but i also didnt want to leak all over.

This has happened to every 240 I have ever owned and to every friend I know that has one (assuming that it is leaking from the front. If not, then it is a different problem). So if it is leaking from the front, its an easy fix. Under $10. Go to Autozone or a parts store and pick up a front crank seal. Make sure its the front. Sometimes in their computer it may be listed as timing cover seal. Take off your belts. Then use an impact to loosen the big bolt on the crank pulley (harmonic balancer). Then pull it off and behind that is your front crank seal. Pry the old one out with something. Then put the new one in, dust seal lip facing outward. But use something flat to push it in evenly. Then re-assemble. It's actually a really easy job and should definately fix your problem. Oh, and after your done, change your oil back to normal because I doubt your engine is liking that thick ass oil. Change the filter too. Hope this helps.


sorry to jack but you say that the harmonic balancer is there, and i read that buyin a pulley can mess up the balancer and slowly ruin the engine, is this true? would buyin a UR pulley or ASP pulley wreck my motor?

no it wont ruin the engine
underdrive crank pulleys are exactly the same size, just lighter weight and stronger material.
its like buying a light flywheel on the other side of the engine.

underdriving accessories can be more difficult
dont underdrive your alternator if you run any extra electronics in your car because it will drain your battery and wear out the alternator faster
underdriving the water pump will make it pump coolant slower and possibly lead to overheating
underdriving the power steering will only make your steering slightly stiffer but not that bad

91300zxTT, get a FSM if you don't have one already.

oh and call it a crank pulley
the term harmonic balancer came from older v8 engines that werent very precisely made so they needed an extra reciprocating device to balance engine movement
import engines are balanced pretty well from the factory so they really dont need a balancer.
if you talk to any muscle car lover he'll tell you how much power and reliablity can be had by a professional balance and blueprint job, but imports dont benefit as much
some engines with a very long stroke (such as the SE-R spec v) use internal balance shafts, but even these cars dont really require them to run reliably.

yah i had just read that somewhere and though it was a good time to ask

They have crank pulleys that are liquid filled, this 700hp R34 in Modified Mag had one if I remember correctly, the liquid spreads evenly along the inside wall so it automatically balances itself.

No worries xcusememisswyn, I got some help so ask questions if you want. I would have posted this in the Technical section, but of course its always doing it's disappearing act.

oh yeah inline six engines are naturally unbalanced by design so there is always something to compensate on those engines

i thought all other engines were unbalanced and needed balancing shafts but the inline-6 was the only one that DIDNT need balancing??? am i full of shit? i swear i remember reading that.

I6 and V12 engines are the only two engins that are naturally harmonic and balanced or something, I've always heard that all my life.

can anyone confirm this? thats what i remember hearing too.

I heard Valentino something or other, the Lamborghini test driver say "V12 is like musica".

LOL they are.