Classic Alfa Forums

Hi guys - the Nova is still dropping a bit of oil, and interestingly it appears to be coming from two locations at the top of the engine, so may not be the usual sump gasket, or worse still, the dreaded crankshaft oil seal.

I've had a really good look around the engine today and the first source appears to be coming from the oil pressure switch located above the oil filter. The electrical connector at the top of the switch is wet with oil and the bottom of the oil filter is also covered in fresh oil. It may be the filter is leaking around the seal but I will deal with that at the next oil change. I have ordered a new oil pressure switch as a matter of course, as it's only a tenner.

The second source is on top of the engine and the oil is accumulating in the core plugs on the nearside. It is engine oil and not clutch slave cylinder hydraulic fluid. The oil pressure sender is dry around the base, so it isn't coming from there either.

Which I think just leaves the distributor oil seal. My engine is a 1980 1.5 Ti but my distributor is from a 1978 car, so is running on points instead of electronic. I am looking to reinstate my electronic distributor in the near future, but for the time being I would like to get a new oil seal on the points distributor.

Does anyone know if these oil seals are available individually? If not, do they come as part of a full engine gasket set, because I have two part-used sets that may yield this item? They are in storage, hence my question!

I seem to recall AHM selling blanking plates to plug the distributor hole on engines with direct ignition, so I guess crankcase pressure can cause this kind of oil leak.

Any opinions/advice gratefully received!

Lauren

Sounds like it's worth a quick check of the PCV system to me, both issues could be crankcase pressure related.

Do you suspect the O ring on the dissy drive shaft?

Never had a problem there, but I've got a packet of O rings/washers left over from an engine rebuild.

PM me your address, and I'll post them if you wish

Could it be leaking around the base of the oil filler tube? That would be a cheap fix.

Thanks guys - the oil leak is not around the filler tube, it does seem to be coming from the distributor shaft. As aircooled VWs use the same type of Bosch distributor I reasoned that the oil seal will be of the same diameter, so I have ordered a couple from Machine 7.

Mj2k, you are right that the crankcase breather could be responsible for the distributor leak, but as the oil pressure switch is on the pressure side of the oil pump, the pressure should be high here - and it is, particularly now that the days are getting cooler.

I am running a sort of halfway house breather set-up, I have replaced all the smallbore pipes at the base of the carbs but retain the plastic collector (with its built-in pipe cleaner), twin pipes to the air cleaners (K&N's with marine style breather stubs) and the large bore pipe connecting to the oil filler pipe. I will check all these pipes to make sure they are not blocked before I do anything else.

New oil pressure switch and O-rings are on their way...

Lauren

OK, here's a quick update.

New oil pressure switch, points and condenser off ebay (all Bosch branded parts), new distributor oil seals from Machine 7 (on the basis that the most ubiquitous vehicles on the planet - apart from the Honda Cub of course) use the Bosch JFUD as well.

The oil seals are Brand X, so a few flash lines to clean up, but otherwise a direct replacement. I removed the distributor and it was quite clear that the seal had been leaking - the well in the rear engine cover casting was full to the brim with congealed oil. I siphoned that out and had a look at the oil seal itself, which was severely deformed. The new seal went on relatively easily, and I took the opportunity to replace the points and condenser and set the gap.

Putting the distributor back in on the other hand!

Try as I might, I couldn't get the distributor past the shoulder on the rear engine cover. In the end I had to move the clamp plate down the shaft so that the locating stud could be used to put some pressure on, and then I had to lever against the chassis to finally pop the seal into place. No question that the old one was worn beyond repair!

Next I turned my attention to the oil pressure switch. After fabricating a lever arm extension for my 24mm ring spanner I was finally able to remove the old switch - it is covered in fresh oil from top to toe - I think the oil has been leaking under pressure from the electrical terminal on the top. Fitted and torqued the new switch in place and so far, so good - no more oil coming from here either.

There is just a suggestion of a weep from the oil filter can itself, but I will address that at the next oil change.

Lauren