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GMC V6 and V12 Engines Engine repair and rebuilding

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  #1  
Old September 28th, 2016, 10:07 AM
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Default Oil (I think) leak

I noticed a quarter sized oil spot on the concrete the other day. After crawling underneath and taking a look, it would appear that there is indeed a leak.

Without laughing too much (I'm learning as I go), can anyone tell me what the picture I've attached is? The part I'm interested in is the square headed bolt, as there was a drop of oil on it (I'm assuming it was oil, looked and smelled like it).

Am I being overly optimistic in thinking that this is going to be something that is easily fixed? Based on its location I mean.
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Last edited by Jmclendon; September 28th, 2016 at 10:07 AM. Reason: Brain working faster than fingers, or the other way around.
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  #2  
Old September 28th, 2016, 01:51 PM
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Default Re: Oil (I think) leak

Looks like the transmission drain bolt. Probably not your culprit since it has tranny fluid, not oil

Being the lowest point it probably dripped from something down to there and from there to the garage. That's an awful small amount of oil (quarter size) but some things to check:
Clutch slave cylinder
Valve cover gaskets
Road Draft tube (very hard and vengeful iron tube coming out of the back and running down the back of the motor - don't bang your head on it)
Oil filter
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Old September 28th, 2016, 02:09 PM
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Default Re: Oil (I think) leak

I would think, in a Country with Quite a few Land Rovers, a quarter size spot of oil would be good news. I belonged to a Landy club, you could always find the meets by following the oil trail.
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Old September 28th, 2016, 04:58 PM
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Default Re: Oil (I think) leak

Quote:
Originally Posted by FetchMeAPepsi View Post
Looks like the transmission drain bolt. Probably not your culprit since it has tranny fluid, not oil

Being the lowest point it probably dripped from something down to there and from there to the garage. That's an awful small amount of oil (quarter size) but some things to check:
Clutch slave cylinder
Valve cover gaskets
Road Draft tube (very hard and vengeful iron tube coming out of the back and running down the back of the motor - don't bang your head on it)
Oil filter
Unless it's an automatic it'll use gear oil. Which has a distinct smell for sure. LOL! Especially after 50 years.
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Old September 28th, 2016, 05:00 PM
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Default Re: Oil (I think) leak

Quote:
Originally Posted by Jmclendon View Post
I noticed a quarter sized oil spot on the concrete the other day. After crawling underneath and taking a look, it would appear that there is indeed a leak.

Without laughing too much (I'm learning as I go), can anyone tell me what the picture I've attached is? The part I'm interested in is the square headed bolt, as there was a drop of oil on it (I'm assuming it was oil, looked and smelled like it).

Am I being overly optimistic in thinking that this is going to be something that is easily fixed? Based on its location I mean.
If you were to look at the inspection cover do you see any oil dripping from the hole in the bottom of that cover? If so, means either the back of the pan or the rear main. If it's just a tiny bit of oil I wouldn't worry. haha It's when it turns to a puddle something ain't right. Unless it's a detroit diesel.
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  #6  
Old September 28th, 2016, 09:10 PM
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Default Re: Oil (I think) leak

Mc:
First step would be to spray some engine cleaner under there and pressure wash to get it clean. After the pressure wash you would have a better chance to see where it is coming from. If it is that square plug seeping some tranny fluid, you can try tightening it a bit. That plug is a pipe plug with tapered threads. Tightening it a bit would solve the problem if that is the source.

Hope that helps.
Regards,
Steve
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Old September 28th, 2016, 10:52 PM
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Default Re: Oil (I think) leak

Quote:
I would think, in a Country with Quite a few Land Rovers, a quarter size spot of oil would be good news. I belonged to a Landy club, you could always find the meets by following the oil trail.
Surprisingly, it's a bit of a nanny state over here. If you get out in the country it's not too bad. But, in the cities and suburbia there's a whole stack of rules and regulations looking for problems to solve. When it comes to cars, you can't get a roadworthy (similar to a safety inspection) if there's an oil leak of any kind.

The good news is I got the roadworthy after it got out of the shop, but before I put any miles on it (IE, before issues like this cropped up).

I know it's not the biggest deal in the world since it's not a big leak. But, I'm choosing to see it as a learning experience and an opportunity to tinker. Also, the old boy has a lot of years left in him. I want to make sure he's well looked after.

Quote:
Unless it's an automatic it'll use gear oil. Which has a distinct smell for sure. LOL! Especially after 50 years.
It's a manual. To be honest I wouldn't know what gear oil smells like. But, it definitely looks/smells like engine oil.

It's had all of its fluids/oils changed out (among a fairly long list of other stuff).

I'll do some crawling around underneath and see if I can definitively identify the source of the leak, rather than just where it looks like it's dripping onto the ground from.
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Old September 29th, 2016, 01:14 AM
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Default Re: Oil (I think) leak

If you just had fluids changes very recently, it's just some spilled oil. You fill some things until they overflow. If that is the case, it will go away soon. Also in the same vane, Mike the mechanic didn't tighten something good enough. It all depends on if the work was recent or not. I always have drips after having my oil changed at Wal-Mart. I do watch their every move since I have always done that myself until my older days. They actually do a good job and cheaper than I can. Newer F150's like mine have a very bad oil filter location, Ford even put a catchment "pan" under it to catch the spill so it can drip after I get home. That ain't fahrvergnugen. I do like the truck in all other areas.
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Old September 29th, 2016, 01:26 AM
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Default Re: Oil (I think) leak

Quote:
If you just had fluids changes very recently
They were changed a few weeks ago (along with a stack of other work). But, we had some other issues crop up that delayed driving it as much as I would've wanted (sloppy shift linkage, a wheel bearing that locked up, a turn signal deciding it wouldn't flash anymore).

Having said all of that, the leak has only started now that I've been driving him around a little bit each day.

One thing that I've noticed when I last checked the oil is I think the mechanic has put a bit too much in. While cold, it's a touch above the "max" line on the stick. Not sure if that's relevant.....
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Old September 29th, 2016, 02:14 AM
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Default Re: Oil (I think) leak

Quote:
Originally Posted by Jmclendon View Post
One thing that I've noticed when I last checked the oil is I think the mechanic has put a bit too much in. While cold, it's a touch above the "max" line on the stick. Not sure if that's relevant.....

Found your trouble. You're the mechanic, remember?

So with driving it a bit you might be sloshing that additional oil out through the draft tube, but you also might have positive crankcase pressure from gunked up vents. It's common enough. There's a PCV on newer 305's, but I'm not sure how the pressure works on the older ones. I haven't gotten into my engine elbow deep yet. Someone else will have to chime in on that subject.

I do know if you're building too much pressure in there the front rope seal often goes.

EDIT: I missed Ken's reply above. I didn't think about the mechanic dribbling oil all down the side of the motor. That might be your trouble too, in which case take a rag to it and give it a week to see if it goes away!
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