340 Rear Main Seal and/or Oil Pan leak

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TRWRacing

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I have a 1973 Dodge Dart 340 that supposedly was rebuilt 3,000 miles ago, but I did not speak directly with the previous owner as it was sold on consignment. It is a definite oil leak and not trans oil on the converter housing and wet in between the oil pan. After driving and parking it will leave a spot about the size of a 50 cent piece on the garage floor.

With it running it will leave a drip every few minutes. I do not have the ability to tackle this and am planning on having it addressed by a local shop that I trust next spring when funds are available.

Is there any harm in driving it while keep an eye on the oil level until it gets repaired?. In 200 miles, I have not seen it move on the dipstick. I am running conventional Valvoline 10w-40 with a ZDDP additive.

Thanks much!
Eric
 
TRWRacing said:
Is there any harm in driving it while keep an eye on the oil level until it gets repaired?. In 200 miles, I have not seen it move on the dipstick. I am running conventional Valvoline 10w-40 with a ZDDP additive.
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I've driven cars in the past with worse leaks than that, as long as the oil level is good, it shouldn't hurt anything, other than make a mess.

Have you by chance checked for a leak up around the oil pressure sending unit back of engine right on top?
 
Bad Sport said:
I've driven cars in the past with worse leaks than that, as long as the oil level is good, it shouldn't hurt anything, other than make a mess.

Have you by chance checked for a leak up around the oil pressure sending unit back of engine right on top?
Click to expand...

Sorry, forgot to mention that. I have checked the top back on the engine: oil pressure sender, valve covers and intake. No leaks from the top. I can deal with the oil mess until it's fixed.
 
As long as the leak doesn't get 'larger', run it. (d/d use of course :) ).
Also, maybe a 'snug up' on the pan bolts may help, who knows.
And, a cursory pressure wash once in a while --- oil on hot exh pipes--- = bad juju .
 
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You might try an tighten up the oil pan bolts, they sometimes come loose from vibration. As for driving the car, just keep an eye on the oil level and you will have no problem.
 
Thanks for all replies!
What does d/d use stand for?
"(d/d use of course :) )"
 
Doh. My bad... Nope, this is a father-son enjoyment weekend summer car. My first car in 1989 was a '71 Dodge Demon 318 that my son told me that I should never have sold - lol. I was a big Mopar fan in High School and would go to my local drag strip for Mopar Days and a local Flukeys for Friday night car shows. There's 50s style hot dog stand near my house that has started having car shows.
 
When I was into Jeeps and off roading, there were guys that swore by the Lucas Oil Stop leak stuff. They used it for small leaks, obviously nothing major. I personally have never used it, so I dont have any experience with it, but check all of the obvious areas first, and if the leak doesnt go away, its something else to consider. Im not saying use it, but its a option.
 
I have heard stories about collaging oil filters or it fixing the rear main seal from leaking after attempting to repair it multiple times. I'm not sure if I want to take the chance.

I also wonder if switching to a Valvoline 10w-40 High Mileage would help, but that is a synthetic blend and I have been running conventional.
 
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