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Rear main leak, possibly?

TJ1978

TJ1978

I have MANY questions
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Edit: solutions/fix were reached on page 4-5

I checked oil pressure sender area and no leaky there, same for valve covers. Distributor is clean as well. The valve cover gasket visibly has oil on but when the truck is running it’s not running down.

Could oil leak from the head? I can see where the block is dusty and where the oil is. Right above the filter area. When it’s running it drips fairly consistently, it’s not gushing out or anything but.. it dripsz

Nothing is coming out the dust cover hole though making me think it’s not the rear main seal.

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Right... I think it’s the head or a spot higher up I just can’t see. I used my little telescoping mirror and didn’t see anything.
It’s weird..

Maybe an oil galley plug on drive side? Do all 350’s have that?
 
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Yes. But I can’t see also, once the exhaust gets cooking it’s hard to reach up there or down...

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Bent77 said:
Back of the intake?
Click to expand...

I’ve rubbed my hand all over this darn thing and get nothing that would indicate it has the leak that is causing this amount to accumulate by the oil filter. I was just out there and had my son shine a light up while I use my telescope mirror.. I get nothing, while sitting or when it’s running.

I’m going to take off the dust cover and see it anything presents itself. Either way I’m getting a bit fed-up with this... at least today. It’s better when it just sits in the driveway, whenever I drive it, something falls apart or fails. This engine has less than 300 miles on it.

So it goes I guess. 10 miles of driving = 1 month or more of fixing that 10mile drive.

Rant over, it’s dinner time...
 
TJ1978 said:
I’ve rubbed my hand all over this darn thing and get nothing that would indicate it has the leak that is causing this amount to accumulate by the oil filter. I was just out there and had my son shine a light up while I use my telescope mirror.. I get nothing, while sitting or when it’s running.

I’m going to take off the dust cover and see it anything presents itself. Either way I’m getting a bit fed-up with this... at least today. It’s better when it just sits in the driveway, whenever I drive it, something falls apart or fails. This engine has less than 300 miles on it.

So it goes I guess. 10 miles of driving = 1 month or more of fixing that 10mile drive.

Rant over, it’s dinner time...
Click to expand...
Welcome to my world. Every time I drive this thing I find something else that needs attention. At least it’s not doing this number after sitting for a day or two.

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That galley is what I thought as well.,, I’ll try again tomorrow. It’s a bitch, once it gets hot it’s hard to reaching all around the engine, especially where this oil may be coming from...
 
My 6.2 drips oil from the same location and I know what you mean about it being a bitch to see up in that area--lying under it with it running getting hot oil dripped in your face (and hopefully not my eyes) is very difficult...

To me it appears to be coming from between the head and block,but I'm not sure it has any oil passages the head gasket is supposed to seal...it could be the valve cover,or oil oozing into the valley under the intake and draining back there,I cant tell..
I know its not coming from the oil cooler ports..its further up..

After watching the oil level carefully I estimate it loses a quart about every 600 miles..slow enough for me to say :flipoff2: to fixing it,I'll just dump a fresh quart in it every month or so...it has other leaks too,the oil pan is mostly holes plugged with bolts and covered with Mar-Glass waterproof bondo...
My truck has been a member of the "drive me 50 miles and a dozen things wrong with me will appear"club lately too...sucks when you have only one vehicle for transporation,you cant lay it up for long to fix anything "right"..good thing I don't go far from home..
 
I’m not opposed to just keeping oil with me and topping it off.
I just want to know where the F it’s coming from. Hahahahaha
 
TJ1978 said:
I’m not opposed to just keeping oil with me and topping it off.
I just want to know where the F it’s coming from. Hahahahaha
Click to expand...

I'm the opposite. I want to know where it leaks so I can fix it. Especially on a new motor.

I had to have the 350 TBI replaced shortly after I bought my 87 K5. Bought a rebuilt 350 from a reputable engine builder. Got the new 350 installed and after letting it warm up a freeze plug was leaking antifreeze. Just a seepage but still......a fresh rebuilt motor. It was on the side of the motor so I drained the fluid....popped out the freeze plug and installed a new one. I took it to them afterward to let them know what happened. They said I should have brought it in and they would have taken care of it. Wasn't necessary since I can do it myself. No big deal. I know sh!t happens.

IMHO......find it, fix it, forget about it. But that's me.
 
The leak I described on my 6.2 ends up on the exhaust manifold & pipe ,surprisingly it doesn't get hot enough to even make it smoke or stink,I guess diesels have a lower exhaust temperature,or 15W-40 has a high flash point ?...at least those parts wont rust ,they'll be the only two that aren't or wont!..it doesn't leave pools under it,just some drips..

I probably sound like a jerry rigging hack,and admit I am since my physical ability to do my own repairs is rapidly waning....but I do and did enjoy doing things "right" and having peace of mind in the past,though sometimes things still gave grief anyways,despite being anal and doing everything by the book..:surepal:
 
I’m not opposed to topping it off but I’d much rather find and fix as well. To me, an engine that is damn near “new” from a rebuild shouldn’t be having this leak at all.

But since it ‘s been 1 1/2 years since the rebuild and that same amount of time working on the truck my “warranty” has long since expired. As soon as I got the engine . Tcase went south, then the tranny. It’s been one thing after the other. The only thing not “new” is the wiring harness.

The engine has 250-300 miles on the rebuild.
 
"So it goes I guess. 10 miles of driving = 1 month or more of fixing that 10mile drive."

Trust me, I know. I suspect many of us do, if we don't drive ours daily.

Last few years I've had the fuse panel melt (heater fuse), heater core and radiator fail, cruise control quit, fuel pump leave me stranded a couple times, SM465 drain plug that is impossible to stop from leaking, failed input shaft seal in the NP241, wipers that won't shut off, fuel tank vent that won't vent, clutch master cylinder failure, brakes (both service and emergency) that don't work quite right, cracked windshield, incessant tailgate window issues, failed oil pressure sender/switches, and I guarantee more I'm forgetting. And that's from driving MAYBE 1500 miles a year.

I'm glad I don't track miles per problem, and these are the reasons I will not drive an old used vehicle daily anymore. I HAVE started keeping a spreadsheet when I do major repairs or services with fairly long intervals (antifreeze, brake fluid, etc) so that I at least can keep up on the stuff that should be changed out periodically to try and prevent failures associated with exceeding the lifespan of the fluids or whatever. I've also taken to having a box of spares in the truck. Nothing major, but a storage bin that holds a spare water pump, fuel pump, hoses, etc.
 
It’s a bit aggravating. I’m trying to just be able to go have some fun in the desert. But if I can’t drive 10-15miles around the neighborhood then it stands to reason, I won’t even make the drive to the desert to have fun. Let alone make it back or.. Even if the truck can do the above And Im positive enough it can. Im just not overly confident it can.

I don’t mind a little weeping of oil, but this oil is coming with a small but consistent dribble. Not being able to locate it is even more perplexing and irritating.
Once the engine and exhaust are hot it’s impossible to do further digging around it.

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TJ1978 said:
It’s a bit aggravating. I’m trying to just be able to go have some fun in the desert. But if I can’t drive 10-15miles around the neighborhood then it stands to reason, I won’t even make the drive to the desert to have fun. Let alone make it back or.. Even if the truck can do the above, with it’s track record, Im not confident it can.

I don’t mind a little weeping of oil, but this oil is coming with a small but consistent dribble. Not being able to locate it is even more perplexing and irritating.
Once the engine and exhaust are hot it’s impossible to do further digging around it.
Click to expand...

I can't stand leaks. I've got an oil leak "issue" on mine I don't have on my cars. I never use a wrench to tighten the oil filters. But for some reason, on the truck, if I don't REALLY put effort into tightening it as much as possible, it leaks. It always had a drip at the bottom of the filter that drove me insane, and I thought it was something else loose and leaking because why would it leak from the oil filter? Never had a vehicle do that.

I also hate when I get someplace having towed my trailer, and see wet spots on it from where I've obviously been losing fluid from the truck that has been blown back on it. Rrrrr. I've got enough crap to worry about failing to keep the truck running, worrying about fluid levels due to leaks shouldn't be part of that equation, at all.
 
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