The oil leak dilemma

[terryismyride]

I am guessing this is a common problem for this mileage.

It's an 85 with 180,000

looks like this

It started leaking oil a bit and gradually became a bit worse.

I had the bright idea of trying to fix it myself I need to learn how to fix cars better. If this gets solved then my Terri is mint!!!

I had been checking out where it was leaking from for months, and it turns out to be heavily around the oil pan. It doesn't seem to be leaking from other areas, except behind the timing belt (crank case?) -- could that be a valve cover gasket?

A mechanic friend recommended putting on the valve cover bolts (it was missing two) and that didn't help much.

(those in the know will probably cringe at this) In the last few days I tightened up those bolts a bit and then tightened up the bolts on the oil pan (they didn't seem tight). It was better for a bit. Then the problem got much worse. Probably from putting increased pressure on the gaskets? I filled up the car with oil and Luca's "stop leak" formula, and ran it for 100 miles. The car seemed to be running much better but it turned out to be leaking way more oil! It's really bad!
So two big questions -

1) If I loosen the bolts a bit (about where they were before) will this have a even more negative impact or will it relieve pressure and won't leak so much?

2) what could be the problem? valve cover gaskets? oil pressure sending unit (doesn't look so hot)

Probably should take it to a mechanic at this point but if there's anything I could do with my tools I'd be willing to give it a shot. Thanks. (car noobie sorry)

*update* i did loosen up the bolts a bit. i figured it could not hurt as much as being too tight (and being in the arizona heat, those gaskets would be expanding too far! ) it was leaking oil even after just sitting out undriven for a day. I desperately need to get my knowledge up I don't want to ruin this beauty.

[dlb]

if you don't have much in the way of wrenching skills, now is the time to work on them. the good news is that these cars are incredibly simple and easy to work on so they're perfect for mechanics-in-training. more good news is that as long as you make sure the engine always as oil in it, you aren't going to kill it. just make sure you can fill it up faster than it leaks.

you should not have tightened the oil pan bolts. they are meant to be done up very lightly. too tight and the gasket material gets crushed, squeezes out, etc, which causes leaks. it sounds like yours needed replacing already though so don't beat yourself up over it.

before you replace it, i would check all the other engine oil seals so that you can do them all at the same time. to do that, clean the engine off really well using rags and spray cleaner. take it for a drive and then take a good look at it to determine where the leaks are coming from. common places for leaks are at the valve cover (the very top of the engine), the distributor (rear driver side corner, the thing the spark plug wires go to), the fuel pump (rear passenger side corner, opposite the distributor), the cam (upper front, behind the black timing belt cover), the crank (lower front, behind the big pulley), and the oil pan. the crank seal is the hardest to determine due to the pulley being in the way. for the cam seal, you must remove the upper timing belt cover.

chances are more than one are leaking so i would do them all at once. for the oil pan, i like to use silicone gasket maker rather than cork or whatever. i find it's cheaper and there's no chance of coming home from the parts store with the wrong part. just follow the instructions on the tube.

good luck. keep us updated on how it goes.

[Petros]

welcome to the forum!

As DLB points out, these are usually simple fixes. Rarely does an oil pan leak, it just looks like it does because it drips down the block and runs around the oil plan lip, making it appear to come from it. Best not to mess with the oil pan bolts unless they are too loose now, overtightening them is not helpful because it can damage the gasket.

the most common sourse of leaks is the valve cover gaseket, including the half moon plug at the back of the head (right under the gasket). it must have all the cap nuts in place or it will leak like crazy no matter what you do. But again, do not over tighten them. First thing is to get a new oil cover gasket, often the get old, stiff and brittle as they age (hmmm, sounds too familiar), and they also get leaky (I am not quite there, yet...). So get a new gasket, clean off the old one and install it. After than clean the engine with degreaser and water, or go to a coin op pressure washer and get the engine real clean. than you can watch for new leaks to verify if you got it or not.

Next most common place is the distributor o-ring (inside the base of the distributor), that too is not too bad to replace, and it costs about $1.00 (there are threads on removing and replacing the distributor, you MUST follow the procedure or it will not run after you put the dist. back in). other places that it could leak is the sender, the front crank or cam seal, or the rear seal. sometimes the fuel pump leaks oil from the gasket as well.

Cleaning up a messy engine will help you find where it comes from, put in a new valve cover gasket (It is easy) first (do not over tighten it), clean up the engine and than look for other leaks. if your pan bolts are loose, you might snug them down, BUT NOT TOO TIGHT!

good luck.

[terryismyride]

Thanks! This is great information. Cleaning up a lot of the grime, I am pretty sure I know where the leak is coming from but I'm dialing it in.

Learning to fix the car is an incredible feeling, so far:

Replaced a radiator hose, tightened up throttle, replaced pcv hose and some other hoses. Fixed overheating problem! Cleaned up most of the grime from the right side of my car, up and under, checking out all the parts, and it's amazing how different it feels than the left side (more cleaning tomorrow) A/C has been updated and blows super cold. Learned that the Toyota uses the metric system and had to buy some new wrenches.

Also got it leaking less back to point A. Luckily! the area under my car might become the bane of my neighbors,even though I try really hard to keep it in check. Any extra advice on cleaning up oil from asphalt appreciated, for now keeping it extra covered with cardboard.

Getting up wrench skills, soon will replace timing belt.

Very sure it's not the valve cover leaking, it still looks like and drips from the top of the oil pan. That's where it's all wet from oil. Have not seen a leak onto the oil pan yet. Although I doubt it is the oil pan leaking. Cleaning up the engine completely soon, tomorrow I hope, and will get to the bottom of this. It COULD be the distributer, the cam, or the crank. Feeling confident I could fix this myself.

One more question. How do I service my manual transmission? It shifts smooth, but if I decelerate a bit (don't keep the rpm's high) the car jerks around a bit.

[irowiki]

PRessure washer may clean the oil off the pavement. My sedan has left a nasty spot on mine I'll have to try and clean someday.

Speaking of the sedan, it leaks a quart or more every 100 miles. It used to be not so bad, then this winter BOOM. Leaves a drip drip down the road as I drive the inside of the engine bay is now a total mess, it dripped on belts and got flung all over.

I think the crankshaft seal or the camshaft seal is bad and will be replacing them soon.

[Petros]

use powered laundry detergent and a stiff boom and water to clean off the pavement. Laundry detergent has an oil and water soluble substance that will lift the oil so it floats on the water. Scrub it with a broom or stiff brush real good and hose it off. If really bad, use some solvent like paint thinner, and than the detergent. Also a degreaser like "Purple Power" works very well too, scrub full strength, let if site 20 min and than hose it off.

Most oil leaks are easy to fix, the only one that is hard to reach is the rear main seal (the trans and flywheel has to come off) but those are usually reliable. finding them is a little more difficult. But make sure you diagnose the problem BEFORE you fix it, so you do make it worse, or cause new problems you did not have before.

Once you gain some confidence and move on to doing more serious repairs like head gaskets, brakes, clutch, etc. than you will have enough confidence to fix almost anything on the car no matter where you are, as long as you have your tool bag with you, and you can get parts. I have done head gasket replacement several times in a parking lot 3000 miles from home just with the tools I had with me and what I did have I rented from the local auto parts store. Those cars with the replacement head gaskets are still running today many years later with the new owners.