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-   -   Oil (I think) leak (https://6066gmcclub.com/showthread.php?t=49620)

Jmclendon September 28th, 2016 10:07 AM

Oil (I think) leak
 
1 Attachment(s)
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.

FetchMeAPepsi September 28th, 2016 01:51 PM

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

bobdylan September 28th, 2016 02:09 PM

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.

TJ's GMC September 28th, 2016 04:58 PM

Re: Oil (I think) leak
 
Quote:

Originally Posted by FetchMeAPepsi (Post 63812)
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. :teehee:

TJ's GMC September 28th, 2016 05:00 PM

Re: Oil (I think) leak
 
Quote:

Originally Posted by Jmclendon (Post 63807)
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. :lolsmack2:

sclor September 28th, 2016 09:10 PM

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

Jmclendon September 28th, 2016 10:52 PM

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.

AZKen September 29th, 2016 01:14 AM

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.

Jmclendon September 29th, 2016 01:26 AM

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.....

FetchMeAPepsi September 29th, 2016 02:14 AM

Re: Oil (I think) leak
 
Quote:

Originally Posted by Jmclendon (Post 63821)
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? :poke:

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! :D

Jmclendon September 29th, 2016 02:22 AM

Re: Oil (I think) leak
 
Quote:

Found your trouble. You're the mechanic, remember?
LOL I wish. I've never been a car guy. But, there's something about the truck that has piqued my interest enough to do the best that I can. Unfortunately, because I've only recently started learning/tinkering, that means a lot of the work to date has been done by a classic car garage.

Does anyone happen to know what the oil pressure gauge reading should be while it's up and running? At the moment I think I'm running in the 60's, which seems a bit high?

If so, is that something else which would be impacted by having slightly too much oil in it?

AZKen September 29th, 2016 03:50 AM

Re: Oil (I think) leak
 
60 is good......... and no, too much will not will not affect pressure. A little over the full, on stick, is nothing to worry about.

TJ's GMC September 29th, 2016 06:26 PM

Re: Oil (I think) leak
 
Long as your not a quart overfull you'll be fine. I think new pumps are rated at 50 psi. Pending on the thickness of the oil. I need to get a gauge on mine so I can see because I just put a new one in.

My 305 is a 67 so it has the built in PCV system in the heads. With the breathers I have, I have found it common for some oil to dribble out and drip onto the valve cover or towards the back of the motor. After a fairly long drive it's now a custom to pop the hood and wipe the covers down. haha Can't let that pertty paint get oil stained! Never did this until I put the new pump in...telling me the top end if finally getting some oil. Plus...now that the motor is clean internally that helps a tad to. :thumbsup:

Jmclendon September 30th, 2016 12:31 AM

Re: Oil (I think) leak
 
I was a bit off on the oil pressure. It's more like 55 most of the time. Funnily enough, when I checked this morning there was no oil spot. I crawled underneath and cleaned up all around the area where I found the drop coming from. I'm not stressing about it too much at the moment since it's very tiny. But, I think once the new issue that's cropped up has been dealt with I'll have a better look at what's going on and get it fixed (or fix it myself, depending on where the potential leak is located).

bigblockv6 September 30th, 2016 03:48 AM

Re: Oil (I think) leak
 
[QUOTE=TJ's GMC;63836]Long as your not a quart overfull you'll be fine. I think new pumps are rated at 50 psi. Pending on the thickness of the oil. I need to get a gauge on mine so I can see because I just put a new one in.

The V6 oil pumps will show 60-80 psi on the gauge. In fact 67-69 GMC pickups as well as Medium duty trucks with V6 engines up to 74 used a specific 80lb gauge in the instrument cluster. I've seen what happens if you use the 60lb gauge that was for inline 6's and V8's in the V6, the gauge is constantly pegged out.:ahhhh:

TJ's GMC September 30th, 2016 05:31 AM

Re: Oil (I think) leak
 
[QUOTE=bigblockv6;63860]
Quote:

Originally Posted by TJ's GMC (Post 63836)
Long as your not a quart overfull you'll be fine. I think new pumps are rated at 50 psi. Pending on the thickness of the oil. I need to get a gauge on mine so I can see because I just put a new one in.

The V6 oil pumps will show 60-80 psi on the gauge. In fact 67-69 GMC pickups as well as Medium duty trucks with V6 engines up to 74 used a specific 80lb gauge in the instrument cluster. I've seen what happens if you use the 60lb gauge that was for inline 6's and V8's in the V6, the gauge is constantly pegged out.:ahhhh:

Daaaaang! That's what my big block 572 puts out! :ahhhh: :lolsmack2:

Now I really wanna see! haha

AZKen September 30th, 2016 07:10 AM

Re: Oil (I think) leak
 
Quote:

Originally Posted by Jmclendon (Post 63853)
I was a bit off on the oil pressure. It's more like 55 most of the time. Funnily enough, when I checked this morning there was no oil spot. I crawled underneath and cleaned up all around the area where I found the drop coming from. I'm not stressing about it too much at the moment since it's very tiny. But, I think once the new issue that's cropped up has been dealt with I'll have a better look at what's going on and get it fixed (or fix it myself, depending on where the potential leak is located).

55 is very fine. There is a pressure relief valve in the filter.


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