Checking oil level

[TheDrifter]

I have a 1970 Sport that Ive had for 20 years. Never thought to ask this: do you guys check engine oil level with the engine hot or cold?

 

[sprdv1]

doesn't have to be warmed up...

 

[sprdv1]

And btw, Welcome to the site!

 

[TheDrifter]

Thanks. Should have joined long ago when I bought my first one.

 

[DirtDonk]

Agree. Welcome and you can do it either way.

Yes, there might be a slight change due to heat expansion, but it's not enough to skew whether or not you need oil. After all, you don't need to add when the oil is 1/8" below the line, nor do you have to remove any when it's a tad above the line.
Just add a quart if it reaches the lower line is how I usually recommend. With 6qts in the pan, you're not in danger of ruining an engine by running it on only 5qts. That same 5qts (or even 4 in some cases) is what most Windsor family engines ran anyway.

If you don't mind having a little can of oil left on the shelf however, you can fill it anytime you want to keep it topped off and just add from the can as needed.
Filling it with a full quart simply lets you toss the container and keep things more organized I think.

Just because we're talking about this however, you still need to follow the directions when checking an automatic transmissions. If it says "check when hot" then that's what you do without question.
The needs of an auto trans are completely different from a V8 engine in that regard.

Paul

 

[DirtDonk]

And frankly, as a test (and because people on the internet lie!;D) you can test it both ways so you know from now on what the difference is between hot and cold readings.
This way you know what to expect when you check it hot, vs cold.
After all, sometimes you need to check in different conditions. So you might as well know.

Paul

 

[TheDrifter]

While we are on this topic, this 1970 has always leaked a little. I rebuilt the engine in 2005 and it continued to leak a little, I have no idea why but it has never been an issue around town or on the highway for 4 hours straight. What are your thoughts? Should I tear down the engine again?

 

[DirtDonk]

First of all, where does it leak.
You don't need to tear down an engine to fix an oil pan, or valve cover leak after all.

If it's not an issue around town or on the highway, where is it an issue? Are you saying you only see it when parked, as a drip/puddle underneath?

More information please.

Paul

 

[spap]

I always do oil checks cold because you know all of the oil has dropped back down to the pan

 

[TheDrifter]

When I park it, I'll see a little puddle the next day. The oil gauge does work and Ive never had an issue with oil pressure etc. After 300 miles or so, I'll have to drop another quart into it. When I try and trace the leak it sort of gets lost. I know that is a weak answer but Ive owned two Broncos (both original 302 V8 engines). Owned this one since 1998. Both were always kind of "leaky." Regardless of swapping out valve covers etc. Ive always just figured it is just something you deal with when driving an old original.

 

[NicksTrix]

welcome aboard drifter

 

[Pa PITT]

my Boss requires all us that drive to check our own oil.. But he also has a 5:00 hour kid that's supposed to check all the vehicles . But I THINK he just smokes.
.. We've had a couple of motor go south. So I've always check my own. I don't want that Donkey BBQ. ''ASS CHEWING'' ..
.. BUT the boss wants them checked daily. SO I do check mine most days . See no reason to check them in the rain. But I check mine COLD & I just remember where it was yesterday & When I check it I don't worry about it . It's got oil &it's all same as yesterday . Not the way I learned but . If we check daily it should be good.

 

[DirtDonk]

When I park it, I'll see a little puddle the next day.

Whereabouts is the puddle? Front of the engine, rear of the engine, on the engine? Rearward far enough to be a transmission leak by any chance?
Manual, or automatic trans? If an auto it's easy to see when that's leaking because it's usually pretty much red in color, vs the usual greenish brown of engine oil.

Needing a quart every 300 miles is a lot. Indicative of a very tired engine with lots of miles on it, or one that perhaps has sat for the last several years and is just recently started running again. Or it's leaking more than you think.
A very small puddle under the vehicle very night would need more than 300 miles usually, but if you're only driving it a few miles a day and that 300 miles takes a month, I could see a leak causing it.
Otherwise 300 miles is also burning it, or sucking it up and burning it somewhere.

So, more input again please.
How many miles (just rebuilt?) and how many miles do you drive it? Driving it every day?

And where is the oil dripping from.

The oil gauge does work and Ive never had an issue with oil pressure etc.

Unfortunately for us (from a diagnostic standpoint anyway) an oil leak from any of the usual spots will never be seen on the pressure gauge.
You'd have to be practically out of oil for it to drop pressure. I test-drove my then-new Bronco and it was showing 70psi with just over one quart of oil in the pan.

After 300 miles or so, I'll have to drop another quart into it. When I try and trace the leak it sort of gets lost.

Yeah, we know how that goes. Oil likes to travel. Especially after a drive!
But one of the most common leak points on our Fords, and one that can throw oil all over the place, are the valve covers.
See if you can contort and acrobat yourself over the top of the engine and look down the backside and see if you can tell if there is any oil drooling out of the back of the covers.
It can often be mistaken for a rear-main seal leak because it can drip down behind and out of the bell housing.

Owned this one since 1998. Both were always kind of "leaky." Regardless of swapping out valve covers etc. Ive always just figured it is just something you deal with when driving an old original.

Well, unfortunately you're correct in that! But they can be made dry as a bone too, with mucho diligencio.
Is this an original engine then? Rebuilt in 2005, but that's basically 14 years. How many miles are on it now do you think?
Did it leak this bad right after? Or has it slowly gotten worse over the years?

Check your PCV valve for function, since it sucks much of the excess gas and pressure out of the crankcase. A faulty valve can cause leaks.
And how was it rebuilt and what aftermarket parts were used? Carbureted or fuel-injected?
Some engines are prone to sucking oil up through the PCV valve and burning it, which uses more than it should. Do you have aftermarket valve covers by any chance?

Just a few more things to check.
But at some point, yes you may have to pull things apart to stop them finally. But only if it's something like a rear main, or an oil gallery plug (they're in the back under the bell housing) and stuff like that.
If the cylinder heads were not done, or not done correctly, you could have oil coming through the valve stems and burning that way too. That's not going to leak externally of course, but it could double up your usage and explain the 300 mile exchange rate.

Good luck.

Paul

 

[TheDrifter]

Im taking off on a business trip this AM, but to answer some of your questions as far as I can see the oil is dripping mid engine, noticed a drop actually on the oil filter. It is a manual transmission and original engine which was rebuilt in 2005. It has basically since then until just recently. I haven't been driving it every day, mostly on the weekends as I travel during the week and am rarely around to drive it during the week.

I will check the valve covers when I get back on Friday. Good info.

Since 2005 it probably hasn't had more than 1000-1500 miles on it (if that). The 300 miles was just done in the last 3 weeks. The mileage gauge says 78k and some change, but you know how that goes. It has a 4 inch lift and 33 in tires, so obviously not true mileage. I have tested it and it seems to be .9 to an actual mile (or around that). But again that is a total swag.

Great info for me. It has really been since 2001 that I was driving it as my primary vehicle. She sat in my farmhouse for a decade) so Im still trying to get back into the groove.

 

[DirtDonk]

Hmm, the oil filter, eh? A few culprits jump to mind then.

1. The filter itself of course. The seals can leak if they're old, doubled-up (the old one stuck to the engine when the new one went on), too loose, too tight, buggered.

2. The front of the valve cover. Though this is seldom and easy to see, so is lower on the list.

3. A big front-runner right now is the oil-pressure extension tube. They are notorious for leaking, especially the aluminum ones.
If you think you might dig into this and yours is aluminum, have a new steel one standing by before you try to unscrew the old one. They tend to snap off.

4. The timing cover gasket can leak out of the side and drip down there.

5. The intake manifold can leak in a corner if not just perfect, and drip down.
Both the intake and the timing cover can leak oil down into the little recesses on top of the cover under the distributor.

6. Cylinder head gasket. Not as common either, but there is actually a lot of oil draining back down from the rocker area, so if the head gasket decides to leak in that front corner, it can drip down from just above the oil filter.

That's what immediately comes to mind. You'll have to be the one to clean it all off, drive it around and see if you can determine the origin of course. But at least that gives you a few extra points of interest to keep your eyes on.

Paul