Massive Oil Leak

[Houli]

I'm looking for some help with a very large oil leak on my runner. 2000 limited V6 with 182k miles. I had a pretty bad leak a while back that I managed to track down to where the oil pump sealed to the engine block. See this thread for more info on that.

I now have an even bigger leak coming from the front of the engine. I originally suspected a rear main given the amount of oil leaking. It leaks about a quart of oil every hour of highway driving.

I degreased the engine bay and observed a steady drip from the front passenger side of the oil pan and wiring harness that runs around the front of the pan.

I'm pretty stumped because less than 10k miles ago I did the following work:

-replaced valve cover gaskets, cam plugs, half moons
-reseal oil pan, replaced oil pickup
-replaced oil dipstick tube o-ring
-fresh oil/filter change (the leak is not residue from an oil change)

Let me know if you have any ideas

 

[Septimius]

I'm looking for some help with a very large oil leak on my runner. 2000 limited V6 with 182k miles. I had a pretty bad leak a while back that I managed to track down to where the oil pump sealed to the engine block. See this thread for more info on that.

I now have an even bigger leak coming from the front of the engine. I originally suspected a rear main given the amount of oil leaking. It leaks about a quart of oil every hour of highway driving.

I degreased the engine bay and observed a steady drip from the front passenger side of the oil pan and wiring harness that runs around the front of the pan.

I'm pretty stumped because less than 10k miles ago I did the following work:

-replaced valve cover gaskets, cam plugs, half moons
-reseal oil pan, replaced oil pickup
-replaced oil dipstick tube o-ring
-fresh oil/filter change (the leak is not residue from an oil change)

Let me know if you have any ideas

when you did the oil pan gasket, did you rtv around corners and kinks? not sure if that's applicable on the t4r, but i know on my e36 i had issues with the valve cover leaking when using just the oem gasket and no rtv, looked it up and it turns out you're supposed to add some to the problem areas of the seal

 

[thegipper]

I'm looking for some help with a very large oil leak on my runner. 2000 limited V6 with 182k miles. I had a pretty bad leak a while back that I managed to track down to where the oil pump sealed to the engine block. See this thread for more info on that.

I now have an even bigger leak coming from the front of the engine. I originally suspected a rear main given the amount of oil leaking. It leaks about a quart of oil every hour of highway driving.

I degreased the engine bay and observed a steady drip from the front passenger side of the oil pan and wiring harness that runs around the front of the pan.

I'm pretty stumped because less than 10k miles ago I did the following work:

-replaced valve cover gaskets, cam plugs, half moons
-reseal oil pan, replaced oil pickup
-replaced oil dipstick tube o-ring
-fresh oil/filter change (the leak is not residue from an oil change)

Let me know if you have any ideas

If it is leaking from the front of the engine it wouldn't be the rear main it would be the front main but that is super rare to leak.

My guess is your oil pan is leaking again, something happened or it wasn't installed correctly.

 

[sambishop]

It's certianly possible when you replaced the cams seals and crank seal on the front of the engine they didn't sit right or you didn't install correctly. Did you use OEM parts for that?

 

[sportscarfan]

blocked / stuck PCV?

 

[the walrus]

OP you might consider a dye and black light kit to track down the source of the leak.

https://www.amazon.com/Tracer-Products-TP34000601-Fluorescent-Detection/dp/B000JFHNTM



.

 

[Houli]

I used OEM parts for everything I have replaced so far, including OEM Toyota FIPG. The PCV was replaced when I did the valve cover gaskets. It's possible it got stuck with some junk from the replacement procedure. I'll check it, but I doubt that's the cause.

The leak detection dye is interesting, may go that route.

 

[Houli]

when you did the oil pan gasket, did you rtv around corners and kinks? not sure if that's applicable on the t4r, but i know on my e36 i had issues with the valve cover leaking when using just the oem gasket and no rtv, looked it up and it turns out you're supposed to add some to the problem areas of the seal

The oil pan on this thing is interesting. It had a bunch of RTV smeared all over it from a previous owners work/repair. It also has a dent in the side from what I'm assuming was the previous person trying to get it off. It's possible the pan could be bent. I made sure to thoroughly apply Toyota FIPG per the service manual.

 

[Septimius]

The oil pan on this thing is interesting. It had a bunch of RTV smeared all over it from a previous owners work/repair. It also has a dent in the side from what I'm assuming was the previous person trying to get it off. It's possible the pan could be bent. I made sure to thoroughly apply Toyota FIPG per the service manual.

sounds like a possible culprit for sure. maybe try the dye kit, and if you determine to pull the pan again see if you can get a machine shop to micro it and check if it's square. that or look into a replacement one, not sure what they cost for the 4runners but on my old xterra it wasn't too ridiculous brand new.

 

[Houli]

Got the leak dye and tested it. Here is what i found; pretty substantial leak coming from the sealing surface between the oil pan and pump. Strange because all of the bolts on the pan torqued up fine, and I'm sure I had enough FIPG on the pan surface. Looks like the pan is coming down again...

<iframe width="560" height="315" src="https://www.youtube.com/embed/ksUcF74SWuk" frameborder="0" allowfullscreen></iframe>

 

[Septimius]

Got the leak dye and tested it. Here is what i found; pretty substantial leak coming from the sealing surface between the oil pan and pump. Strange because all of the bolts on the pan torqued up fine, and I'm sure I had enough FIPG on the pan surface. Looks like the pan is coming down again...

<iframe width="560" height="315" src="https://www.youtube.com/embed/ksUcF74SWuk" frameborder="0" allowfullscreen></iframe>

clean the piss out of both, then take a square to both surfaces and make sure they're flat and parallel? maybe some old gasket residue getting in the way of a decent seal?

 

[99Runnr]

I used "The Right Stuff" RTV from the local parts store on my pan. Remove pan, let it sit dripping for a few hours. Clean the bottom of the block, I used a wire wheel on my drill to get EVERYTHING off the surface of the pan. If there is damage to the pan itself, possible someone caused an uneven surface. As mentioned, check the sealing surfaces.

I ran a 3/16" bead all the way around my pan. Let it set up for 15 minutes and used 4 studs to line it up an set it up against the block.

You have an FSM it sounds like, but this worked great for me. The Right Stuff RTV has worked AWESOME for everything, I just started using it in the last 2 years. Water pumps, lower intake gaskets, oil pans, ect, it's designed to put vehicles back into service immediately versus the general stuff that needs time to setup.

 

[Houli]

After digging into it today I think I have things figured out. I pulled the oil pan and the timing belt off to check the oil pump, camshaft seals, and crankshaft seal. I found the oil pump seal had been pushed out 1-2mm from the surface of the pump body. There was evidence that oil had been leaking from the crankshaft seal, as you can see in this picture:



The amount of oil coming out led me to believe the leak was coming from somewhere where oil is under pressure. I'm thinking the pressure relief valve was getting stuck in the pump body due to sludge/debris that was dislodged from either the valve cover gaskets being done or oil pan/pump removal and re-installation. It did not fall out right away under its own weight when I removed the bolt that holds it in. I'll clean the cylinder it slides in and replace the valve when I reassemble.

I'm not sure if I should just put the seal back in or use some RTV to hold it in place. It came out extremely easily.

 

[sambishop]

I'm not sure if I should just put the seal back in or use some RTV to hold it in place. It came out extremely easily.

dude do not reuse that seal

 

[Houli]

Got a new seal from the dealership today :barf: It is not the same as the one I put in last time I had the oil pump out, it is the same as the one I originally pulled out when I took the oil pump off though. Both seals claim to be OEM, but I think this new one actually is. I've got it seated nicely in the oil pump body, ready to put everything back together. I ultimately decided using RTV to hold a seal in place is a hack job, so I just pressed it in like it's supposed to be.

 

[Septimius]

Got a new seal from the dealership today :barf: It is not the same as the one I put in last time I had the oil pump out, it is the same as the one I originally pulled out when I took the oil pump off though. Both seals claim to be OEM, but I think this new one actually is. I've got it seated nicely in the oil pump body, ready to put everything back together. I ultimately decided using RTV to hold a seal in place is a hack job, so I just pressed it in like it's supposed to be.

wonder if they screwed up the p/n and gave you the wrong seal last time. i don't much trust the guys at the parts counter, on the bimmer i normally check realOEM for the part numbers and give them those directly vs asking them to look them up. not sure if that's an option for the t4r

 

[Houli]

wonder if they screwed up the p/n and gave you the wrong seal last time. i don't much trust the guys at the parts counter, on the bimmer i normally check realOEM for the part numbers and give them those directly vs asking them to look them up. not sure if that's an option for the t4r

I'm not sure what the deal was with the different seals. The leaky one came from a timing belt kit I bought on eBay that was supposed to contain all OEM parts. I got everything buttoned up a few days ago and it has been fine. It survived a few hundred mile road trip last weekend with no leaks at all.

 

[Diezel]

I ultimately decided using RTV to hold a seal in place is a hack job, so I just pressed it in like it's supposed to be.

It's funny you that. For decades, I myself, and other tech's I have worked with have put a thin coat of RTV on seals as we install them. 1: It provides a tiny bit of lube for putting the seal in. 2: It helps the seal stay in place and seal if there is any small imperfections.

Note, that on many seals these days, there is now a ring of different rubber already on the seals from the factory, as an additional sealing and retention aid.

So I wouldn't be so fast to call it a hack job.

 

[Houli]

It's funny you that. For decades, I myself, and other tech's I have worked with have put a thin coat of RTV on seals as we install them. 1: It provides a tiny bit of lube for putting the seal in. 2: It helps the seal stay in place and seal if there is any small imperfections.

Note, that on many seals these days, there is now a ring of different rubber already on the seals from the factory, as an additional sealing and retention aid.

So I wouldn't be so fast to call it a hack job.

I guess I was wary of doing that because I ran into a situation where the previous owner used RTV, probably way too much, to install the camshaft seals. When they leaked, I could not get them out using my seal puller and had to ultimately pull the valve covers just to get the seals out. It caused a lot more work and hassle for me. Whoever owned this runner before me did some other questionable repairs to it which makes me think they were definitely a hack. I can understand your reasoning, but like you mentioned, modern seal design has kind of eliminated the need to do that.

 

[Diezel]

I guess I was wary of doing that because I ran into a situation where the previous owner used RTV, probably way too much, to install the camshaft seals. When they leaked, I could not get them out using my seal puller and had to ultimately pull the valve covers just to get the seals out. It caused a lot more work and hassle for me. Whoever owned this runner before me did some other questionable repairs to it which makes me think they were definitely a hack. I can understand your reasoning, but like you mentioned, modern seal design has kind of eliminated the need to do that.

As I said, many, not all. And FWIW, Most vehicles, the "cam seals" are partially captive in the valve cover. The ones that are not unless they are a really poor fit, need a removal tool specifically for the job.