Oil leak around oil pan

[sunfic]

LX470 2006, about 200k miles.
Found oil leak around upper and lower oil pan, from bottom I can see it is a around the lower oil pan.
Where it could be the leak point? Is it possible the dipstick tube?
I will check tomorrow to see if any higher leak oil stain.

 

[crolison]

Is it on both sides or one side? I am having the same leak on the drivers side. With cleaning things up my suspicions were the oil cooler block gasket or the valve cover gasket. Since valve cover is higher i changed that and cleaned up again, and still seeing a little fresh oil on the cooler cooler.

 

[sunfic]

Is it on both sides or one side? I am having the same leak on the drivers side. With cleaning things up my suspicions were the oil cooler block gasket or the valve cover gasket. Since valve cover is higher i changed that and cleaned up again, and still seeing a little fresh oil on the cooler cooler.

On both sides and back side as well. I haven't got chance to check front side yet. will do it today.

I think maybe the leak point is still in higher part because the oil is all around the pan.

thanks for the suggestion will definitely check the cooler line as well.

 

[sunfic]

Found highest leaking point here. The truck had its timing belt changed 20k miles ago. Wondering if it is leaking inside timing belt cover.
Any suggestions? Thanks!

 

[awesomeissquid]

I believe there is a bolt for the timing belt pulley that needs to be installed with a coating on the threads to prevent a leak. Might be possible it didn’t get install correctly when the timing belt was done.

 

[sunfic]

I believe there is a bolt for the timing belt pulley that needs to be installed with a coating on the threads to prevent a leak. Might be possible it didn’t get install correctly when the timing belt was done.

Thanks! that definitely is a possible leak point. I am wondering if that is the case how I can fix it. Do I need to re-do all the timing belt replacement procedure all over again?

 

[2001LC]

Best take lots of pictures of all wet spots. Than clean spotless/de-greasing. Then watch very closely (after ever drive) for recurrence in wet area you found earlier and have pictures of. Important to watching after each drive, before oil spreads, to pin points.

Your oil dip stick o-ring is weeping. This area and around it. Is also where spillage during oil fills flows. Oil filter and it's house/bracket spillage and leaks, may also show here.

The red arrow pointing to time belt tensioner, which I do not see wetness in picture. But between that and the timing belt lower cover, ia area too keep eye on. If oil first appears there, than at weep hole later. It's almost always the time belt RH tensioner pulley bolt threads not sealed.

head cover bolts loosen over time as rubber seals shrink. I re-torque to 53IN-lbf. Head cover leaks do very often make it to the oil pan. So look at head covers also.

 

[sunfic]

Best take lots of pictures of all wet spots. Than clean spotless/de-greasing. Then watch very closely (after ever drive) for recurrence in wet area you found earlier and have pictures of. Important to watching after each drive, before oil spreads, to pin points.

Your oil dip stick o-ring is weeping. This area and around it. Is also where spillage during oil fills flows. Oil filter and it's house/bracket spillage and leaks, may also show here.

The red arrow pointing to time belt tensioner, which I do not see wetness in picture. But between that and the timing belt lower cover, ia area too keep eye on. If oil first appears there, than at weep hole later. It's almost always the time belt RH tensioner pulley bolt threads not sealed.

head cover bolts loosen over time as rubber seals shrink. I re-torque to 53IN-lbf. Head cover leaks do very often make it to the oil pan. So look at head covers also.

Thank you very much! I will definitely to as what you said. I will take pictures and clean them and then watch.

 

[2001LC]

Today, while draining block, prepping to do a Timing belt at 300K miles. I noticed this leak.

I took some picture in the blind, so not very good.
Could be diff side tube seal leak. But oil above, must be coming from elsewhere. So may have multiple leaks, hard to say without cleaning first.
Input shaft of steering rack is dry at seal. So not that.

Very mucky and wet here up front a Timing belt lower area. Crank to seal mating area, looks dry. But around outside edge of crank seal is wet. If leaking around outside lip of seal. That may indicate, it's been replaced before and something went wrong. Some oil at tension pulley bolt hole in oil pump housing. Which is very common leak, if threads not sealed. But thread where seal, somewhat!!!

Looks like I'll be replacing crank seal. It will be my first ever on a 4.7L. My bet is it's not the factory seal.

Area can be cleaned up later, to look for other leak. If any!

 

[DTCsk8er]

I'm probably going to be in the same situation on mine when I get to doing the timing belt in another 5-10k miles; lots of oil residue in that same area.

In your case, it almost looks like someone replaced the seal and didnt clean up the mess the failed seal created.

 

[Coin]

I'm probably going to be in the same situation on mine when I get to doing the timing belt in another 5-10k miles; lots of oil residue in that same area.

In your case, it almost looks like someone replaced the seal and didnt clean up the mess the failed seal created.

I agree

 

[2001LC]

It is likely crank seal was replaced before! Possible leaking before, and not cleaned as you suggested. AS is a lot of gunk. But also consider it's may have just leaked since last T-belt service. Which is 90K miles 7 years. But wherever leak(s) is/are from, it is active now. So bad, oil drip/spot on my shop floor in only a day in.

I took this picture 15K miles 1 yr ago.

Today. Clearly a lot more gunk, just 15K & 1 yr later

It's also, now that I think about. Possibly in part due to excessive crank case pressure!

This has been a difficult T-belt jobs. Alternator 12mm nut stuck on stud, requiring alternator be removed (second in as many weeks). Very common RH T-belt cover crown nut stuck on stud (happens every time over torqued). Fan bracket top side mount bolt (AC compressor to bracket bolt) cross threaded into fan bracket (seen this once before), was a bear to get out.


Excessive crankcase pressure (combustion gasses):

I woke-up thinking, it may be leaking so badly, because of excessive crankcase pressure. Pressure as a result of excessive combustion gasses. I had noticed, when I pulled air pipe. The relatively new OEM PS side PCV hose a bit oily at each end, which I found curious. In addition, due to some vacuum leaks concerns, I'd found and corrected in a past service. I did a compression test a few days ago, before pulling T-belt. I did find 4 low, and 1 of those cylinder below minimum. Wet-test confirmed, all 4 compression loss at rings.

The 4.7L 2UZ would likely go 1 million possibly even 2 million miles, without compression going below minimum. If properly maintained and service. It is one of the greatest engine ever built IMHO.

But I've see compression issue many times, due to a few things other than blown head gasket(s) & warped head(s) due to cooling issues (improper service). Those dealing with either improper (lazy) service when R&R intake manifold (No. 1 cause of failing compression test), air filtration issues (weak compression), oil & filter issues (weak compression), COP (coil) top seals not replaced (No. 2 cause failed test). Failed compression or low compression, these 4.7L engine will still run most times good enough. There are many on the road with low compression. That I'm sure of. They just keep ticking!

To reduce crank case pressure. Proper vacuum (no leaks), and a good PCV valve are important consideration:
So, I'll toss on new PCV valve. Very likely it's gummed-up some, although not stuck last inspection. This could help reduce crank case pressure.
Crank seal may help, if it indeed is leaking the major leak point.
Some AT-205 can help with oil pump to block O-ring seal, and other rubber oil seal.
Cam seals look fine, so I'll not touch those. In fact I've never had to replace factory cam seal.

 

[sunfic]

Report back to my oil leak: it is the crank seal.

Unfortunately I had to go through all the timing belt works until I could locate the issue. The picture I showed here is after I cleaned little bit around the seal. It is annoying that the oil leaked from the seal will be carried with timing belt and spreading all over other places. You can hardly tell what is leaking without removing everything there.

“Since I was there”, I changed (only 20k miles) timing belt, water pump, almost all the idler and tensioner, serpentine belt, fan clutch and bracket, and radiator, coolant hoses… took me almost 8hr finishing the job. It is not very hard but the fan clutch nuts were really PITA. Two of them were rounded I had to chisel them out… I don’t know if there is any tools for fixing the fan clutch to make the job easier.

 

[Hu1k]

Is it on both sides or one side? I am having the same leak on the drivers side. With cleaning things up my suspicions were the oil cooler block gasket or the valve cover gasket. Since valve cover is higher i changed that and cleaned up again, and still seeing a little fresh oil on the cooler cooler.

Did you ever figure out what yours is? I’m having the same leak, corner of the pan drivers side.

 

[OEMGUY0720]

Will post this here since it’s related to the oil pan and components to fix leak/weep. I accidentally broke one of the OIL PAN STUDS/Bolts and it needs to be replaced. I will be extracting it using an extracting tool but I will need to prepare the replacement stud/bolt first. My predicament is it’s not available in partsouq. What’s your alternative for this specific stud/bolt? And what is the correct FSM torque spec of these studs so I don’t break them again. Thanks.

 

[jerryb]

Nappa has a good selection of metric bolts, assorted lengths also.

 

[OEMGUY0720]

Nappa has a good selection of metric bolts, assorted lengths also.

Appreciate it Jerry, thanks I’ll give em a visit tomorrow.

 

[bigredmachine]

What’s your alternative for this specific stud/bolt? And what is the correct FSM torque spec of these studs so I don’t break them again. Thanks.

bolts for the oil pan isnt really anything special, you should be able to get them at a dealer no problem. if you go to the bolt bin at napa or another auto store its a 6x1.0 and i think the length was 15mm. toyota dosnt list a torque spec for studs so till their seated and somewhat tight, use your judgment on those. if your worried about the studs backing out you could use a dab of blue loctite on them

 

[OEMGUY0720]

bolts for the oil pan isnt really anything special, you should be able to get them at a dealer no problem. if you go to the bolt bin at napa or another auto store its a 6x1.0 and i think the length was 15mm. toyota dosnt list a torque spec for studs so till their seated and somewhat tight, use your judgment on those. if your worried about the studs backing out you could use a dab of blue loctite on them

I will sure take note of this information thanks Big Red.