Any Thoughts on this Oil Leak?

Let me preface this by saying I know very little about engines. I've done a ton of work on my 4Runner in the past 7 months but it's been mostly suspension and brake work.

I'm trying to track down the cause of a small oil leak. It accumulates on the skid plate as well as at the oil drain plug (lowest point I presume). Oil plug is tight with fresh gasket. I've added maybe 1/4 quart in 2500 miles, just to get the level to the top of full on the stick.

I added some dye recently but then it rained for days. When I finally got under to take a look, the dyed oil had sprayed everywhere. I wiped everything clean after the rain stopped and the next day noticed dyed oil on the left side and bottom of the oil pan, having come from somewhere above. There was also dyed oil along the bottom of the steering rack. Most notable to me though was a pooling of dyed oil in the highlighted spot in this image:

ixEU95F.jpg


In April of this year I hired someone to replace my TB, WP, TS and VC gaskets. That's where this picture is from. It's also why I decided to learn to work on this 4Runner myself.

I should have checked long ago but I took a torque wrench to the 4 outer bolts on each valve cover yesterday and they all took multiple turns to get to 53 in/lbs. I was thinking that might be the source of the leak and I'd just need to learn what to remove to get to the other 8 bolts. In the image above it looks like it was a problem even before that work was done. I had no leaks for a couple months after the work in April. I drive maybe 250 miles/month. Currently just over 250k. I don't know if any of that is relevant.

Wish I had current pictures but here's a tighter shot:

xIE3vxR.jpg


Any suggestions as to where to focus my research on this? Is it something obvious? Maybe crank seal? Again, I know very little about engines but I'm keen to learn. I have the technology. I can make her better than she was. Better, stronger, faster. ( everyone here has a little Oscar Goldman in them, no? )
 
Register to hide this ad
Let me preface this by saying I know very little about engines. I've done a ton of work on my 4Runner in the past 7 months but it's been mostly suspension and brake work.

I'm trying to track down the cause of a small oil leak. It accumulates on the skid plate as well as at the oil drain plug (lowest point I presume). Oil plug is tight with fresh gasket. I've added maybe 1/4 quart in 2500 miles, just to get the level to the top of full on the stick.

I added some dye recently but then it rained for days. When I finally got under to take a look, the dyed oil had sprayed everywhere. I wiped everything clean after the rain stopped and the next day noticed dyed oil on the left side and bottom of the oil pan, having come from somewhere above. There was also dyed oil along the bottom of the steering rack. Most notable to me though was a pooling of dyed oil in the highlighted spot in this image:

ixEU95F.jpg


In April of this year I hired someone to replace my TB, WP, TS and VC gaskets. That's where this picture is from. It's also why I decided to learn to work on this 4Runner myself.

I should have checked long ago but I took a torque wrench to the 4 outer bolts on each valve cover yesterday and they all took multiple turns to get to 53 in/lbs. I was thinking that might be the source of the leak and I'd just need to learn what to remove to get to the other 8 bolts. In the image above it looks like it was a problem even before that work was done. I had no leaks for a couple months after the work in April. I drive maybe 250 miles/month. Currently just over 250k. I don't know if any of that is relevant.

Wish I had current pictures but here's a tighter shot:

xIE3vxR.jpg


Any suggestions as to where to focus my research on this? Is it something obvious? Maybe crank seal? Again, I know very little about engines but I'm keen to learn. I have the technology. I can make her better than she was. Better, stronger, faster. ( everyone here has a little Oscar Goldman in them, no? )

FWIW, I have a recurrent film of oil in the same exact spot. Not nearly as much oil as on your truck, but same location. I can't stand greasy motors, and try to fix every source of leakage that I see. I've replaced the valve cover gaskets, as well as the crank seal when I did the timing belt. And I can see that there is no seepage from either of those, yet the oil at that location keeps coming back. I replaced the dipstick o-ring (you might want to check that on yours), to no avail.

I was all set to replace all the hoses and o-rings for the oil cooler, but when I looked closely, there was not a hint of oil leakage from there.

So I"m at a loss too. The only thing I can possibly think of is perhaps a bit of oil spilling during the oil changes (oil filter is in that area), and eventually making its way to that area above the oil pan.

I'll be keeping an eye on your thread to see if you find your source.
 
I kinda doubt this would throw that much oil all over the place but you might check your dipstick seal. That picture above looks like its coming from there. When I did my valve cover gasket job the seal on it was pretty bad and had some oil around it. Its fairly easy to fix tho, so it shouldn’t take much to knock that off your list.

Just get some of the Toyota FIPG sealant, unbolt the bracket holding the dipstick guide to the engine, pull it, add some FIPG to the end of the guide where it mates with the pan, reinsert and install, and let sit for a bit. Make sure you clean around/on the dipstick so no grime gets into the pan.
 
In April of this year I hired someone to replace my TB, WP, TS and VC gaskets. That's where this picture is from. It's also why I decided to learn to work on this 4Runner myself.
Any suggestions as to where to focus my research on this? Is it something obvious? Maybe crank seal? Again, I know very little about engines but I'm keen to learn. I have the technology. I can make her better than she was. Better, stronger, faster. ( everyone here has a little Oscar Goldman in them, no? )

In your picture there is no crank seal installed, so it must have been replaced with the timing belt. Maybe it wasn't installed right. Could also be dipstick tube seal, oil filter, oil cooler, oil pan gasket, oil pressure switch, cam seals or cam end plugs. The valve cover gaskets are the number 1 source of oil leaks on the 3.4L, but they have already been done and the first sign that they are leaking is a burning oil smell because they typically leak right onto the exhaust manifolds.
 
Thanks for the replies and suggestions. The engine's a lot more oily in that pic than it is now but I still need to give it a good cleaning at some point. I forgot that I'd asked the guy to replace cam and crank seals at the time so those should be good. I don't see any leaks around the filter or cooler. I do need to get in there and tighten the remaining VCG bolts but I'm not seeing any dyed oil in that area so I think I'll start with the dipstick o-ring.

I ordered a new dipstick tube o-ring from the dealership and some Aisin gasket sealant from Amazon - the Toyota FIPG wouldn't arrive for a week. Should all be here tomorrow. I'll update with the results after I get it changed.
 
To really nail down a leak, you need to do a good cleaning of the engine so you can find the fresh oil. The age-old grime can hid things pretty well.

Start with tightening the valve covers - slowly, carefully and work your way around. It is easy to crack the cover if you over-torque it.

Then work your way down. It is possible to have a totally leak free 5VZ... Then you just have to figure out the tricks to a no-spill oil change.

-Charlie
 
The only other thing in that area is the oil pump. Is it possible it has a microscopic leak? You really should see it if you clean it really good.

Also is there any possibility that when filling the oil up after changing it that oil isn't spilling and running down the engine?

Just the thoughts I had. :)

Sent from my SM-A505U using Tapatalk
 
The only other thing in that area is the oil pump. Is it possible it has a microscopic leak? You really should see it if you clean it really good.

Also is there any possibility that when filling the oil up after changing it that oil isn't spilling and running down the engine?

Just the thoughts I had. :)

Sent from my SM-A505U using Tapatalk

I can honestly say it's not possible I spilled oil when filling after the last change. I'm actually due for another but I was hoping to figure this out while the dye is still in there (but I have another bottle of dye if needed).

I hope it's not the oil pump but it's entirely possible. Drove to the local DIY car wash recently with a jug of Purple Power and a couple scrub brushes but discovered the city closed it down. I'll have to figure out another way to do a thorough cleaning.

The leak appeared after maybe a 5 mile drive previously. I wiped it down again today after replacing the oil dipstick o-ring and didn't see anything after a short test drive. I guess I'll see what it looks like after a longer test drive tomorrow.
 
I can honestly say it's not possible I spilled oil when filling after the last change. I'm actually due for another but I was hoping to figure this out while the dye is still in there (but I have another bottle of dye if needed).



I hope it's not the oil pump but it's entirely possible. Drove to the local DIY car wash recently with a jug of Purple Power and a couple scrub brushes but discovered the city closed it down. I'll have to figure out another way to do a thorough cleaning.



The leak appeared after maybe a 5 mile drive previously. I wiped it down again today after replacing the oil dipstick o-ring and didn't see anything after a short test drive. I guess I'll see what it looks like after a longer test drive tomorrow.
It would be great if it was just the dip stick o ring..:) as that's an easy fix

Sent from my SM-A505U using Tapatalk
 
I replaced the oil dipstick o-ring and that pooling hasn't returned where I wiped it clean. So I got that going for me, which is nice.

gI3hnT3.jpg


But there's still something leaking. Pic makes it look like the Valdez but it was just a thin layer.

ZvaoYF9.jpg


The only VC bolts I haven't tightened are the inside 4 on the left side so I guess I need to investigate further (and earlier - this getting dark at 4:30 thing really grinds my gears). Or could a VC leak on the left side make its way to the right of the skid plate like that?
 
Changing the oil dipstick o-ring didn't hurt but it sure didn't fix anything.

IzHXNby.jpg


The dye really makes it stand out.

9cEWjtT.jpg


The main area it's collecting in is the right side of the skid plate, just in front in front of the steering rack.

qHc53Ru.jpg


It seems to be coming from somewhere above that on the right side of the engine but I need to thoroughly clean everything somehow so I can figure out where. I'm way out of my wheelhouse on this one. I suppose I could start by removing the timing belt cover and checking there. Certainly open to any and all suggestions.
 
The key with finding a leak with oil dye is to start with as clean of an area as possible and then checking for leaks often. I always let it run for a few minutes after adding dye and then rechecking, then I go on a 1 mile trip and recheck, then a 5 mile trip and recheck. You want to find the leak when it's as small as possible to help narrow it down.

It's quite possible that it's coming from a crankshaft or camshaft seal and then finally leaking out at the bottom of the timing cover area.
 
Plus 1 with Bad Luck as most likely the causes. The only other thing there is the oil pump itself. I can't say I heard of the oil pump ever leaking. Possible I guess

Sent from my SM-A505U using Tapatalk
 
Plus 1 with Bad Luck as most likely the causes. The only other thing there is the oil pump itself. I can't say I heard of the oil pump ever leaking. Possible I guess

Sent from my SM-A505U using Tapatalk
I'm unfamiliar with the oil pumps on these engines. Are they external in any way to the engine? I'm used to GM oil pumps which are usually internal to the engine so any oil pump leaks never make it to the outside of the engine if that makes sense.
 
I'm unfamiliar with the oil pumps on these engines. Are they external in any way to the engine? I'm used to GM oil pumps which are usually internal to the engine so any oil pump leaks never make it to the outside of the engine if that makes sense.
Well these are right behind the crankshaft pulley. You can see them with everything off for a timing belt change. I do believe you have to pull the oil pan as well to service them. On these engines they are external cover.

When I pull my oil pan off I take some photos. As mine in all 3 timing belt changes you can see the pump plate. As it's right behind the crankshaft seal.

I have never had a v6 oil pump off yet so that's all the more I know at this time.

Sent from my SM-A505U using Tapatalk
 
The key with finding a leak with oil dye is to start with as clean of an area as possible and then checking for leaks often. I always let it run for a few minutes after adding dye and then rechecking, then I go on a 1 mile trip and recheck, then a 5 mile trip and recheck. You want to find the leak when it's as small as possible to help narrow it down.

It's quite possible that it's coming from a crankshaft or camshaft seal and then finally leaking out at the bottom of the timing cover area.

I didn't see a leak the first 2 drives after I added the dye but then it started (and continued) to rain in Sacramento for the first time in maybe over a year. By the time it stopped raining the dye was everywhere. Wish I would've hiked up my skirt and checked it in the rain.

I'm a bit nervous about getting in the engine bay with the diy car wash wand but I guess at this point, like Obi Wan Kenobi, it's my only hope.
 
I am also tracing an oil leak exactly the same location. I find it is more oil when you fill the oil to the max mark. After watching this thread, I replaced the dipstick oil seal, Notice how the wire harness is squeezed between the dipstick tube and coolant inlet? I moved the wiring to the other side of the dip-stick tube. I cleaned the area and is monitoring any fresh oil.

I replaced the crank oil seal with OEM seal back in 2010 when I lived in Reno. I do not think it is the crank oil sea. Inspected the belt and it is dry as a bone. Even after 11 years and 45K miles the OEM belt is like brand new!

I also got the alternator brushes done at the same time. I am at 216K miles and alternator brushes are in their last 5% of life.
 
I saw no oil behind the timing belt cover but the lower left cover bolt was oily.

I cleaned things up best I could with some Dawn and a toothbrush and rinsed it clean.

VanLhlF.jpg


After a 1 mile drive I think I now see where it's coming from. With my seriously limited knowledge, would I be correct in thinking crank seal?

ZsaStw7.jpg


For what it's worth, the work I had done 7 months ago included:

Timing belt
Water pump
Thermostat
Belts and radiator hoses
Valve cover gaskets
Spark plug seals/grommets
Crank seal
Cam seals

I had no clue what he was talking about at the time but I remember him asking if the half moons needed to be done. I replied "You're the expert, you tell me". He said they "looked fine" and didn't touch them.
 
Lower left bolt on which part? The top cover? Middle section or the crankshaft cover?

Sent from my SM-A505U using Tapatalk
 

Members online

No members online now.

Forum statistics

Threads
278,316
Messages
3,554,111
Members
248,016
Latest member
Advally Service

Trending content

Back
Top