Oil leak from front crank seal 1979 2000

[maxdog]

Hi
My Fiat has caught the old British car disease , there's an oil leak from the front of the engine , I suspect the front crank oil seal is on the way out . Leak is not dramatic , just enough to mark my son's new driveway and upset She Who Must be Obeyed .
How difficult is this to fix ?
Is it a DIY job or do I need to find a competent FIAT mechanic
Can it be done with the engine in the car ?
If the engine has to come out , is there a rear oil seal which should be replaced?
Presumably the job will then escalate to replacing the clutch , gear box oil seals , Guibo , and on to a complete mechanical rebuild if I'm not careful .
Any advice from those who have been there before me ??
I suppose a no cost alternative would be to park on the street and not the new driveway !!
Thanks
Maxdog

[RRoller123]

Yes, it can be done with the engine in the car, and you can change the other front seals as well, while changing a new timing belt (some change the water pump proactively too). Knock off a whole bunch of stuff at once! I found it easiest to pull the radiator, it can be done with it in, but the risk of damage to the rad fins, and the tight working quarters makes it a pita.

[18Fiatsandcounting]

Leak is not dramatic , just enough to mark my son's new driveway and upset She Who Must be Obeyed .
How difficult is this to fix ?

Do you mean how difficult is it to fix the leak, or to placate "She Who Must Be Obeyed"?? I can offer thoughts on the former, but on the latter, not so much.

As mentioned above, you can replace the front oil seals with the engine in the car. Probably the hardest step will be to remove the nut that secures the crankshaft pulley. The preferred solution is either an impact wrench or put the car in gear (this doesn't work with automatics) with the brakes on, and whale on that puppy with a long breaker bar. Definitely should remove the radiator as noted above, and take great care not to round the nut with an ill-fitting socket as you would have a heck of a mess at that point. I can't recall the exact metric size, but 36 mm seems to stick in my mind. Don't hold me to this, though.

Do you know for sure that the oil leak is the front crankshaft oil seal? Could it be the oil pan gasket, or some of the other possibilities in that general area? I would hate to have you go to all the work of replacing the seal, only to find out it was something else. You could clean off the bottom of the engine (degreaser, lots of rags, high pressure garden hose, etc.) and then see if you can spot where the oil is appearing. Might take a few weeks, though, unless the leak is fairly significant.

To replace the rear crankshaft oil seal, the transmission and bellhousing have to come out, and at that point, you might as well put in a new clutch and pressure plate and throwout bearing, unless you know them to be relatively new. I would not suggest rebuilding the transmission oil seals and gaskets as that's another can of worms, although transmissions can be a significant source of leaks.

Remember to replace the gaskets for the oil seal mounting flanges while you're in there.

I don't know your level of ability, but it can be done by a person fairly familiar with car work. I wouldn't recommend the job for a relative beginner, though.

-Bryan

[samakijoe]

Here's a trick that I use to remove the nut that secures the crankshaft pulley.

A little scary but it does work.

After you pull the radiator. Put the 36mm (I think) socket on a "breaker bar". With socket installed on the nut, place the handle of the beaker bar on the floor of the driver's side. (this assumes that your car was made to run on good old USA roads. (If your car
has the steering wheel on the "wrong side" of the front seat you will have to adjust breaker bar placement accordingly.)
Next, remove spark plug wires. Engage starter for just a really short time, the nut should be laying on the floor.
That's the easy part. The tough part is getting the correct torque on the nut when you put it back on.

Anyone have any ideas on that one?

[18Fiatsandcounting]

I suppose that would work, but I would worry about a couple things: 1) the socket partially slipping off and then rounding the nut, or the socket flying off completely and breaking something in the engine bay (cover the socket/breaker bar with a heavy towel??), and 2) breaking a tooth either on the starter motor shaft gear or the ring gear around the flywheel.

That nut can be pretty tight, though. The time I did this with the engine in the car (transmission in 5th and emergency brake on), I used about a six-foot long breaker bar and I could just barely get that nut off. The emergency brakes didn't hold enough, so I had a friend sit in the car and push hard on the brake pedal. It worked, but geez...

Penetrating oil might help. I use Kroil, but others recommend PB Blaster. The latter is pretty easy to find. Heat with a low flame from a propane torch can also work to loosen stuck nuts, perhaps 30 seconds or so on the nut. I urge extreme caution with any open flames around an engine, of course.

-Bryan

[samakijoe]

-Bryan: What is your technique for re-torquing the nut?

Also: Has anyone used my way of removing the nut?

[18Fiatsandcounting]

-Bryan: What is your technique for re-torquing the nut?

Transmission in 5th gear, emergency brake pulled tight (or a helper pressing the brake pedal), and a two foot torque wrench. Clean the threads beforehand on both the end of the crankshaft and the nut. My Haynes manual for the Fiat engine specifies 88 ft lbs for this nut, which isn't really all that tight, although I'm sure you could go much higher. For reference, the wheel lug nuts are around 80 ft lbs.

Since I had a Fiat crankshaft pulley fall off once while driving down the road (for unknown reasons), I'm now paranoid and tend to tighten somewhat more. I can't recall exactly, but probably somewhere around 120 ft lbs, but not more than 150.

Any advice on what the best torque for this nut should be?

-Bryan

[wetminkey]

Please check my thread on "Head Gasket Replacement" for pics and info on how to remove the 38mm crankshaft nut. It's easily done with a chain wrench on the crankshaft pulley and long breaker bar,...I use my 1' drive ratchet and 1 1/2" socket. No rounding the nut, no stress on the tranny. Easily done,...with the proper leverage.
And my car has an automatic transmission!
BTW, the Fiat Shop Manual calls for this nut to be torqued to 181ftlbs. And it recommends the use of anti-seize prior to re-installation.
Todd.

[maxdog]

Thanks for the comments to date . I will certainly clean up the engine to confirm the source of the oil leak
If the crank seal leaks it looks as if I should replace the cam drive belt , possibly the water pump ,at the same time
.What other seals are there at the front of the engine ?
Has any one pictures of seal replacement or a reference to a ' "Child's Guide to seal replacement " ?
Thanks again
Maxdog

[wetminkey]

Again, Maxdog, check out my current thread "Head Gasket Replacement", it covers a lot of this,...
You'll want Auto Ricambi's timing belt kit, or similar. Belt, bearing, water pump with gaskets, and coolant "T" gasket.
I have not replaced my crankshaft seals with engine in the car, so I can't be of help in that respect,...I know it is done on V8s.
Best of luck with your chore!
Todd.

[18Fiatsandcounting]

BTW, the Fiat Shop Manual calls for this nut to be torqued to 181ftlbs.

Wow, perhaps that's why my crankshaft pulley fell off way back when, if I was following the 88 ft lbs spec in the Haynes manual. 181 ft lbs sounds a lot more appropriate, and also would explain why this nut can be a bear to remove.

Do you know if this spec varies by model year? I think my Haynes manual only covers 1438 through 1800 engines, and I now have a 2L block (the one that lost the first crankshaft pulley on the freeways of LA). Perhaps I was just clueless and using the wrong spec?

-Bryan

[tonym]

Check your oil pressure sensor too. I had a leak near the filter and it was the oil pressure sensor and its crush washer not tight enough. Don't know if there's torque spec for that. Maybe you'll get lucky and not have to pull the crankshaft pulley and seal.

[samakijoe]

Maxdog: If your still no sure as to the location of the leak I would do a really through cleaning of the engine.
Drive it for a couple of days and you should be able to see where the leak is coming from.

[wetminkey]

P.S. My Fiat Shop Manual is 'specific' to 1975 - 1982, as far as I can confirm,...
Crankshaft nut with anti-seize: 181ftlbs for those years,...mine's a '79 2000cc.

[18Fiatsandcounting]

I came across some info (although I can't find it right now) that listed, for all engines except the 1438 cc, this nut should be torqued to 180.3 ft lbs, but the 1438 engine was indeed only 88 ft lbs. Weird. I'll have to look into this some more.

-Bryan