1989 740 Turbo, Oil Leak from front Crank Seal
 

Hi,

I just read a bunch of the entries dealing with oil leaks. I just fixed the leaks from the 2 pipes that connect to the bottom of the oil filter housing and was hoping that this is end of my leaks. Well the oil slick at work's parking lot was slightly smaller, however only slightly. The oil does not leak from the oil cap, the valve cover does not leak and the front seals on the camshaft do not leak.

Without taking the timing belt covers completely off, my guess is that the front crankshaft seal ~$5.00 part is responsible as I can see a small trail of oil coming out from the bottom of the engine just behind the timing belt covers, the timing belt is not covered with oil.

My question: Is the front crank seal easily replacable AFTER the front crankshaft pulley and the crankshaft gear are removed?

[ I have done the timing belt maintenance a couple of times, so I know what I need to do to get the all of the "stuff" off that is at the front of the engine. One emergency maintenance was on my son's 89 740 Turbo, when teh rubber in the front pulley gave out and teh alternator belt was cutting into the fron timing belt cover and starting to rub against the timing belt... this was a real close save... ]

Thank youin advance.

before you go too much farther, you should make sure the crankcase ventilation system, specifically the 'oil seperator box', isn't all fouled up. if this gets plugged up, your engine blows oil seals right and left.

THEN fix the bad seals.

To gain access to the front main seal, you need to remove the crankshaft pulley. Behind it is the timing belt gear which will just slide off once the pulley has been removed. Make sure you mark the parts carefully and align the engine to TDC prior to removal of all this. While you have it apart, you might want to replace the timing belt.

I replaced the cam seal on my 240 a couple of weeks ago. Basically the same procedure. Took me overall around 3 hours.

As Pierce said though, check the flame trap. Make sure it is all clear otherwise you can replace the seals all you want and they'll keep blowing out your new seals if the crankcase venhilation system is clogged up.

Pierce, Act1292,
I cleaned out the crank vent system this summer, it was actualy quite clean...
Thank you for confirming that the front crankcase seal can be replaced from front. I totaly agree, if one takes all of the belts off, it makes no sense to reuse the old ones. The only thing that I am undecided is if I shoud put in a new water pump, the current one has about 50,000 miles - I think I will replace it....
Thanks again.

if its a good original quality water pump, those are good for 150K or more miles. but the replacement pumps are all over the place in quality, some much worse than others. and the seals supplied with the cheap aftermarket pumps are total junk

I always check the water pump bearings for play when I have the belts off. If you don't have any weeping of coolant from the pump and the bearings are tight, I keep the old pump. It's not a definitive test as the seals could fail the next day. It's not a large job to get to the pump if you have to do it later (not like a front wheel drive car).

My experience has been the same as Pierce. The Volvo pumps give a long life (I've only had to replace a pump once and that was about 150k). My other Volvos I bought with 180k on them and none of them have needed a pump. I assume the previous owner had it done around the 150k mark.

Continuous drips.
 

The crank and cam shaft seals were replaced just before Winter, this reduced the oil leak to about half. The sealss were relatively easy to remove and slide the new ones in...
Now that Winter is finaly over, I examined the replaced seals, they are nice and dry. I looked around under the car and I will have to do the oil pan gasket. Looking at the shape of the oil pan, it looks like it would just about clear without undoing the motor mounts... unfortunately from reading the forum, the engine will need a slight lift to remove the oil pan.

The PVC system is all clean, flame trap is not plugged up.

Pierce

what about GMP water pumps? it says made in Japan...