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Oil Overfill

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jdeluke137

jdeluke137

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Hi. I've posted a few times here. I've had my 76B for a little over a year, but I just found this forum in the last couple of months. I live south of Atlanta - I drove a brand new 74B in 74, purchased from Hix Green Buick for $3700 - and dated my wife in it. A year ago I came home and she had the current one in the driveway. Said she was ready to date again since the kids were grown. She's a good wife.

Now to my question. Every time I change the oil, I put 3 1/2 quarts, run it for a few minutes, and then check the oil. Always a little low, so add a little more. But I always get just a little too much. Right now, 30 minutes after a drive I'll show the oil level just over max - maybe a sixteenth of an inch. Am I doing any damage by running it like that, or do I need to do like last time and try to drain a little? If so, is there an easier way than loosening the oil drain plug? Last time, I almost didn't get the plug back in before too much came out!

Thanks for the help!
 
Congratulations on the new B - & the wife!

I'd rather run a tad bit low rather than too much...but, which oil filter are you using?
 
Wix 51085. I took the Purolator L10017 that was on it in to a local import auto parts store, they measured it and then found a Wix to match. I ran a Mann W917 for one oil change, but I didn't like it - I don't think the anti-drainback worked as well. I've seen postings that I should run the 51068, but it was much shorter than the 51085 that matched the Purolator. My oil pressure is good - around 30 at idle, 55-75 at 2500-3000 rpms, depending on how long I've been running.
 
Just hold of on toping the oil after the next change. I like Tony would rather see it a 16th down from full rather than a 16th over.
 
Do you think I need to remove the excess thats in there now? If so, any clever suggestions how other then the drain plug?
 
Jd, You could try a suction gun with a thin piece of tubing in the dipstick hole if you <u>must</u> get rid of the extra oil. Do it with the oil warm to make it easier.
BTW, I used to live in Warner Robins.
Jeff
 
Jd, do not run her over filled. It is not good for her, I would change it again for the under $10 (provided that you are not using synthetic) follow Tony' advise.

Put in a quart less then what you have been, let the oil run down and then if needed do a quarter of a quart at a time and repeat the process.

Patrick
 
Think if it is only a 16th on the dipstick I would live with it, it will blow out shortly.
 
I guess I'll use the drain plug tomorrow. I checked again and now that its cooler its up to about a 1/4 inch above max.

As Patrick says, worst case senario and all the oil comes out costs me less than $10. Last time I was able to stop at about the right place.

Do you guys check your oil hot or cold?
 
Here's my concern:

[qote]My oil pressure is good - around 30 at idle, 55-75 at 2500-3000 rpms

[/ QUOTE ]

That's a first sign the engine is getting a bit tired...at speed oil pressure should be no less than 75 & at idle around 50...putting too much pressure on those rings & bearings will only push the rebuild closer...IMHO
 
Time to use a bit heaver oil??
 
Jack - heavier than 20w50? What would that be?

Tony, she probably is tired - 91000 miles, and I don't know if she was ever rebuilt. I'm the third owner, and the middle guy only had the car for about 3000 miles. But the compression is fairly good - 150, 150, 140, 150. 18V801 engine.

Like I said, I'll drop the level tomorrow. I'm not in a position to do a rebuild right now!
 
No, 20W50 is good...are those compression checks dry or wet?
 
My 1973 MGB came from Hix Green. Do you still have the rectangular 'Hix Green' plastic trunk emblem? Mine was destroyed when it was hit in the rear for the THIRD time.

Alan T
 
Tony - dry compression numbers. I haven't done a wet test.

Alan - no, I don't have it. I sold that car in 77 - DUMB MISTAKE! And mine didn't have the trunk emblem - I told them I didn't want it on the car when I ordered it.

I'm not surprised you've been hit three times in Atlanta - the traffic around here gets worse every day. What part of Atlanta do you live in?
 
I live in Marietta but soon I will be moving to Powder Springs. I've also lost a Jaguar MKIX and MKII to Atlanta drivers.

Alan T
 
[ QUOTE ]
Here's my concern:

[qote]My oil pressure is good - around 30 at idle, 55-75 at 2500-3000 rpms

[/ QUOTE ]

That's a first sign the engine is getting a bit tired...at speed oil pressure should be no less than 75 & at idle around 50...putting too much pressure on those rings & bearings will only push the rebuild closer...IMHO

[/ QUOTE ]

Is this the main reason why Oil level is better low than high? It puts too much pressure on the engine?
 
Oil pressure is not related to oil level, except when there is far too less oil in the engine and pressure drops to zero.

The reason for not overfilling the oil is the big end bearings will hit the oil surface in the pan on each revolution the engine does and stress the material.

At least that's what I've been told.
 
And what you were told is correct. Keeps RPMs down and slows engine down as well.
 
In our engines, low oil pressure can cause problems (but not 1/16" low)...overfill doesn't create any more oil pressure in our engines but it can do what Eric explained above...plus too much oil in curves sloshes around, the big ends are slowed by having to plow through that oil...

Now in some engines, too much oil can wreak havoc - take my 380SL engine, for example, or a Jag engine.
 
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