1998 volvo s70 distributor leeking oil into cap inside. ? bad rubber ring? 5 cyl. non turbo. How do you replace distributor

It is on the side of the Cyl. Block underneath the Intake Manifold just to the right of the PCV System. While you have it apart I would suggest replacing the PCV System entirely.

Clogged up PCV System ---maybe

Too much crank case pressure

There are a few ways, it could be burning oil or making noise or not building pressure,

What problem are you having that makes you think turbo is bad?

sounds like a coil issue

Easy:
1. Check spark plugs
2. Check HT leads
3. Check distributor cap
4. Check rotor arm (in distributor)
5. Check coolant for traces of oil and check oil for sludgy emulsion. Either of these two could indicate a blown head gasket.

Harder:
1. Compression test on all cylinders. This should show if any cylinder has a lack of compression. Lack of compression could be caused by a) damaged valves, b) damaged piston rings. The leak down test will show you which it is.

Even harder
1. Leak down test on all cylinders. If there is air being blown back throught the dipstick tube it is likely that the piston rings are at fault. If air comes back through the throttle body, it may be the inlet valves. If air comes back through the exhaust the the exhaust valves are the likely cause.

In any case it is recommended to fix the problem asap to prevent damage to the engine.

If you check the "Easiest" items (above) and found nothing, I would recommend being towed to a dealer / workshop. If you can't get a tow and the dealer / workshop is less than 20 miles away you could still drive there but with the injector for cyl 3 disconnected. Be aware that in doing so you a likely to stall the engine (especially with automatic trans) and when that happens the power steering and the servo assist for the brakes don't work thus making driving dangerous.

I hope it is something simple, mine wasn't.

Don't remember exactly , but I think it could be done without dash removal.
It's done from driver side footwell area , tight but possible.
You have to take out lower center consol side cover , next to the accelerator pedal and roll the carpet out of the way, and you will see the heater core case. Remove cover on the case (some have it on the side , some on the bottom).Two pipes going from firewall to the core have to be disconnected before core removal (will leak coolant , have some rags on the floor to absorbe it).
Slide heater core out , put new one in gently as the accelerator pedal is on your way , try to avoid damaging core a lot.
Always replace heater core pipes o-rings.

make sure the battery is ok check spark plugs distributor cap and rotar arm for any wear or damage if it has original plug leads replace them also make sure correct grade of oil in engine also clean throttle body

Turbo oil seal is probably bad. This lets oil leak into the air intake from the turbo bearing. If smoke goes away during hard acceration, then this is probably your problem. Turbo replacement or rebuild is the fix for this.

This part will only be available through a Volvo dealer or maybe used from a junkyard. It is the metal base that bolts to the intake cam and the rotor bolts to it. A Dealer can look it up, there isn't really a name, just describe where it attaches to.

ok if the oil is coming out of the distributor it has to be taken right out and marked to go back in the correct spot there is a rubber o ring on the shaft of it.