GHOSTOWLGRID

I know I'm posting another question this soon, but I have to ask because I'm not sure.

Previous owner when he showed me the engine before test running it, had a bolt plugging the fuel pumps return line, how bad is that?

When I first got the engine there was gas in the oil, and it was an obvious smell, but I assumed it was because he was pouring gas in the carb to get it to start.

I've since rebuilt the top half with new C heads, new rods, eledbrock intake, holly carb, etc.

My first oil that I put didn't have a gas smell when removed, the second oil I don't think it does.

The oil seems to turn a little black sooner than expected but seems fine,

Searching online all I found was people saying to test the oil with a lighter and smell it to see.

I have the fuel feed and return lines hooked up properly, I do not have a fuel pressure gauge attached. Carb seems fine, doesn't seem to be leaning out.

I have about a 20 gallon gas tank, driving it about 20 miles round trip being little heavy on the gas pedal used about 1/4 tank of gas, that included letting it idle for like 3 hours while troubleshooting some vacuum lines for the climate controls and stuff, probably half of that was high idle because I wasn't kicking down the choke right away, plus I had adjusted my choke to turn off sooner after all of that.
Thats normal right? I read these engine were gas hogs but I just wanted to make sure.

I forgot to mention, my Holly is a double pumper with mechanical secondaries and its 750 CFM.

Olds64

Please don't do this. Gasoline is highly flammable and motor oil is flammable too so it's a moot point at best.

Take the fuel line off of the carburetor and put it in an empty coffee can. Make sure the coil wire is disconnected. You should have good fuel flow while the engine is cranking.

GHOSTOWLGRID

^ I will check the flow.

Yah, I know gasoline is flammable. lol
Thats why I had to ask, because what I found I didn't want to try, even if its just a little on the dip stick away from everything.

joe_padavano

Pull the dipstick and smell it. If you can smell gas, there is gas leaking into the oil. Yes, flooding the engine or pouring fuel in the carb can cause gasoline to run past the rings and into the oil also.

Plugging the return line on the pump is common practice if the car doesn't have a return line. On the other hand, if you can run fuel return, there's no reason not to. The benefits in preventing vapor lock are well documented.

GHOSTOWLGRID

Ok, thats good to know that plugging the return line doesn't damage the fuel pump.

It might just be the engines slowly cleaning out, I did run out of 5w-30 fossil and used a half quart of 5w-30 full synthetic.
I'll see how it does each day and I'll change it again here in a week, I have another filter ready.

I never smelled gas during the first oil change, so I'm assuming its fine, I'll see if I smell gas when I do the second oil change.

GHOSTOWLGRID

On an oil related note, my Dip Stick tube is now lose, I checked my oil at the gas station and the tube popped out.

I wasn't to far from home so I checked it and went hone, lost about 1 qt of oil from it, jacked it up and put it back together, it stays, I just have to be careful when I check oil level now.

What is a good dip stick and tube to purchase new for this vehicle?

Does the new one just press in?
does the new one have to be bent to fit the curve to go between engine and manifold?

Its a 1971 olds 455 with C heads.

Do they have an option that presses in then a bolt or something holds it in up top to help prevent this from happening again?

MDchanic

A couple of observations:

• 5W30 may be a bit thin, unless it's chilly where you are.

Recommendations were for 5W30, 10W30, or 10W40 between 0° and 60°F, and
10W30, 10W40, or 20W40 if the weather is 20°F or hotter.


• The dipstick tube is not attached in the most consistent way possible.
Either it is unremovable when you want it out, or it won't stay put.
I'd just give a few taps to seat it, then be careful not to pull it out again when you check the oil.


• Fuel pump as noted. I wouldn't bother checking it - you drove 20 miles without a problem.


• 5 gallons in 20 miles is 4mpg.
Unless you've got a 4:11 rear and are driving like a maniac, that's not right.
I did better than that in a '68 88 with a 455 in daily commuting in NYC, driving like I was possessed by a demon.
The 3 hours idling may well explain it, as these cars do not idle efficiently, and the double pumper will steal a few MPG as well, but if you do not see your mileage improve, in the next go-round, start looking for something wrong.


- Eric

76olds

1) You could pull the dipstick pipe back out make a tiny funnel out of cardboard ( A couple JOKER CARDS would do )

2) put the funnel into the dipstick pipe hole.

3) Carefully pour fuel down the funnel into the oil pipe hole. 1 litre would do it. Don't top it off though.

4) Get a helmet, safety glasses and give the wife a kiss goodbye your goin; to work on ur Olds from an internet fix

5) Lite a wooden match, not a cheap paper match, a wooden match !! and for gods sake man, put on the dam helmet

6) lite the match and send it down the funnel putting your head down. ( Lookin for heat expansion for press fit here)

7) If you survive this, stay off the dam internet looking up $hit on how to fix your Olds and ask all questions here.

Put-r-ther
Eric

classicmuscle442

Best way to seat oil dipstick, use a fuel line wrench that fits over it and just seat wrench by block and give a couple soft taps to set it in block.

GHOSTOWLGRID

I also let the car idle a lot while I was fixing my interior HVAC vacuum lines because it was cold outside, one was plugged and the other was not connected properly.
I have the 400 auto and a 2.73 rear diff.

Its about 20'F here, 5w30 is what I had. lol

I estimate my mpg is around 12-16 depending on how I drive, I was also testing the car as I was a bit heavy on the gas the whole time.

Its a 80's cadillac brougham so I assume I'll use more gas to move a car that weighs 4048 lbs.

When I put it back, I was able to push it down to the stamped metal flat part without any effort.
I was hoping a better oil dip stick option existed like one that had a bolt on the top side that held it from popping out, I found a regular replacement on Summit's site, I'll give it a try after I get it and do like you suggested with the wrench.

Olds64

That's a light weight for a 455! If your are getting 12-16 mpg your are doing good.

FWIW, this is the dipstick tube I have on my 455:

https://www.summitracing.com/parts/s...ake/oldsmobile

It works fine but as the others said you would probably be fine by giving your stock one a few good taps to tighten it up. If you were to put in the aftermarket one you could break the stock dipstick off in the block behind the manifold. That would be a major PITA! When I installed mine the engine was on a stand so I didn't have to worry about this.

Fun71

You could clean the tube and the area where it fits into the block, then goop some RTV on the tube just below the flat part, and insert the tube into the block. When the RTV cures it will hold the tube in place.

GHOSTOWLGRID

I felt like sharing this! ^_^
Double checked my mpg again after 67 miles of driving on my 1/4 tank of gas (Assuming 5 gallons for the 1/4 tank b/c 20 gallon capacity full to the gas cap), I just estimated about 13.57 mpg with my 2.73 rear diff doing city driving, lots of stop-and-go's, 5 levels of a parking garage, 25-35 mph roads and some school zones, with a couple 45-55 mph roads. Not counting engine starts and that 10 minutes worth of idle time.


I saw that one, How is it staying in the block for you? is it fit lose at all?
I don't mine the chrome, that would help add a nice touch to it.

The stock dip stick was pretty easy to pull out from the top once it poped out of the block, its very lose, it wobbles easily, it didn't break from what I can tell, it looks complete, I inspected it before sticking it back in the hole.

It was just that I had to jack the car up and go under it to put it back. lol



I thought about that, but I was worried pieces of the silicone might end up in the oil after the new tube is pushed it, stuff sticking in the hole in the block.
It fits very lose, and the stick is somewhat tight in the tube, I just need to replace it.
I'm considering making a top side mount bracket that is held on by a valve cover bolt or manifold bolt and welded to the tube to help hold it in.
I was hoping something like that was already available but I can't find one.

joe_padavano

Sorry, but the gas gauge reading is irrelevant. The gauge does NOT respond linearly and CANNOT be used to measure mileage. If you doubt this, just fill the tank and watch how far you can drive before the needle moves off of F. Do you really think you are getting infinite mileage during that time?

And FYI, your 87 Caddy has a 26 gal tank.

GHOSTOWLGRID

Some places say 25 and some say 18 when I looked it up in the past.
If I'm down 1/4 tank it usually takes about 5 gallons maybe 6.
Its a good enough estimate for me.
Thanks though.

joe_padavano

This may be hard to believe, but much of the info on the interwebs is wrong.

The only source that matters is the factory literature. Look at the owner's manual or Chassis Service Manual and you'll quickly find out that neither of those "places" has correct info.

m371961

How about you write your miles down when you fill the tank, write your miles down when you fill it again and write down the gallons it took? Then use math and see how many miles driven per gallon.
You can also clean your stick housing and the hole and use red Loc-tite on it before installing. Or the RTV, just a little.

GHOSTOWLGRID

Have you tried this before? How well did it hold?

m371961

Not on a dipstick tube.

Olds64

It works fine.

The Loc-tite or RTV should secure your oil dipstick tube though. I suggest doing it in the evening and letting it cure overnight.

olds 307 and 403

The chrome dipstick tubes, bought a few, fit loose and need the end ground down to fit in the block