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2007 Oil Leak - First Ever In a Honda

3004 Views 101 Replies 8 Participants Last post by  plplplpl
I think it’s the front valve cover gasket, and I was able to crank some valve cover bolts a tiny bit more. I was surprise how tight they were.

Is this a common issue? Might mine be over tightened from previous valve adjustment or timing belt service?

It’s got ~160,000 miles on this 2007 AWD EXL.

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Is this a new vehicle? Doesn't look like it was serviced in a while. Check your fluid levels. Make sure you're on level ground. Make sure you are between the marks. Not over, and not under. Trans fluid you check at operating temp (fan comes on) and between 60-90 sec. after you turn off the engine. In that 30 sec. window. Do not check cold, you will overfill. Use Honda trans fluid. What was the last service done?
Use a torque wrench to tighten the bolts to spec. Do not overtighten. That is an aluminum head, and the last thing you want to do is strip out the threads and have to fix that.
I would make sure the trans fluid is correct level. I was curious when you did the valve lash last. Do not wash your engine bay. Looks like someone has already been spraying it down in the past, you can see by all the rust on the bolts and clips. You run the risk of damaging electronics. Not that you will, but that you can. The oil doesn't exactly look wet, so it's not a constant supply coating it. When you remove the cover clean it up real good. I would just use dawn or purple power or some other grease fighter.

This is what I would do.
-Valve cover gasket kit. Don't forget the grommets for the bolts.
-Valve lash
-Throttle body cleaning and new gasket
-EGR and associated passages, channels, ports cleaning and new gasket
-Serpentine belt (I can see yours is getting old)
-Check the pulleys while the belt is off (Spin and listen/feel. Should be smooth and not free spin or come to abrupt stop)
-PCV valve (if the cover has been leaking, the PCV valve is likely gunked up from thick oil)
-check cabin/engine air filters (should be able to see light through them)
-I personally would change all the fluids, but at least change engine fluid, and if Trans hasn't been done in a while, I would also do 3 times drain, fill, drive through all gears low miles, repeat. Honda fluids only except engine oil. Critical you use honda fluids. Add ATP AT-205 once finished.
-If radiator overfill is empty, or if the coolant is not up to the cap, fill and burp the system.
-check and replace spark plugs if they look bad (should be 100k miles if OEM iridium)
If you go with a mechanic to do all these things, make sure you go to someone that knows Honda vehicles. Do not under any circumstance go to an all-in-one mechanic that just knows cars in general. It is very easy for a mechanic to screw up our vehicles. Especially when it comes to valve lash or fluids. It will end up costing you in the long run when you have to have someone else fix their mistakes.
Let us know what you plan to do. At minimum you're going to have to remove the valve cover to see what is going on with the seals.
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It's not getting blown on the cover. You would see it cover everything else. It is just on the cover, so it is leaking from the cover, or at least getting on the cover from somewhere, somehow. Likely from the grommets to the bolts like Nail Grease said. Your valve cover could also be cracked from the accident.
I wonder if that dark discoloration on the top of the throttle body is a leak. It's pretty wide though. Is it oil, or carbon?
If you don't have the tool to remove the spark plug tube seals, you can get to them from the other side, with a flathead and hammer. What you did was grab them too high up. You need to get completely underneath them. The removal tool makes the job easier, but you have to be careful any way you decide to remove them. It's easy to scratch up the mating surface. You don't have to show me what you did, I can already see it in my mind. lol.
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I would switch to a full synthetic oil. You're getting a bit of sludge going on there from all that air that was getting in.
What I was getting at was that the valve cover was no longer sealed, and air was allowed in. This brings moisture and mixes with the oil. Running or not. It does seem that the sludge and the valve cover gasket leaking may be related. As RonnieJ pointed out. You might have more clogged ports causing pressure then you would like. Hopefully the Synthetic oil helps, and don't go to long between oil changes. Especially if the synthetic is knocking lose sludge deposits. I would check your dipstick and if the fluid on it gets thick, you should do another oil change, and not wait for the next service interval.
It's not a constant stream of pressure. More like oscillation, but more positive then negative. Remove your oil cap with the engine running and place a paper towel over the oil cap. You will see it bounce up and down. It doesn't just blow it up, it vibrates the paper towel, but it does it with more positive then negative force. You have to imagine the pressure is coming from up/down movement, from more then one source. Put the paper towel tight over the oil cap.
EGR passages and ports, internal oil channels and ports, Throttle body.
Not the same with the 06-08 Pilots and the Ridgeline with the J35A9, than with the 03-05 Pilot engine.
I've seen the posts where people had clogged passages on the 03-05, and when I took off the intake plenum cover, it was a different design on my 07 than on the 03-05. Different grooves, not nearly as susceptible to gumming up with crud. Still wouldn't be that hard to check, but not as critical on his Pilot and Ridgeline with the J35A9.

NailGrease has a boilerplate list of things to do on these, especially for those that just purchased one, and also a good list, with intervals, to look after when doing your own work - ATF drain and fills, front transfer case, VTM drain and fill, brake fluid replacement, power steering flush (with updated O-ring), spark plugs, PCV, air filter and tube (if cracked), MAF/MAP cleaning (depending on year), always the TB every 100k along with waterpump and new coolant, leaks from rocker arm oil control solenoid assembly (replace the gasket), etc..
You looked at one piece of the puzzle on those EGR systems The channels on top were redesigned so they wouldn't build up with carbon, but the ports between the channels and the EGR still does. Many overlook it, and clean the channels and still have the problem, and can't figure out why. It is a circular system. Exhaust to EGR to intake, to cylinder, to exhaust again. Carbon usually builds up between the EGR and the Intake. It is less likely on the later models to clog on both though, but still clogs.
I would try ATP AT-205 before ever replacing any seals. You should be using it no matter what as preventative maintenance for the other seals that are not leaking yet. I put it in my fluids regardless of leaks or not.
Put some ATP AT-205 in. You should do this regardless. It is a preventative maintenance, and will fix any leaks due to dried up seals. Will not fix holes, tears, ect... It is a plasticizer, and not a petroleum based re-sealer. Which means it will not damage the rubber and make it swell. It reconditions it. You will have no ill effects using this. Do Not use petroleum based sealers. They will cause damage.
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I agree with you that pressure caused your leaks along with time and heat.
It's funny. Your 2 pictures with your finger in them prompted a 18+ warning on them. lol. You obviously have some very sexy fingers. Too sexy for this site.
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It took you up to post #50 to finally recommend AT-205? I would have gone that easy route a long time ago, but that's me.

Seriously, kudos for solving (I hope) this oil leak the old-fashioned way, by eaaarning it. (y)

I mentioned it 3 times. Post #8, #40, and #50. lol.
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Check and order online using code Jan2 for 15% off. Choose local pickup. Might be cheaper, and you can get it today if available.

Full 8oz bottle will treat a 6qt capacity with maximum effectiveness. Adjust usage based on capacity.
I usually put about half in engine oil, 1/8 - 1/16 in power steering, and the rest in transmission. I don't go exact measurement. 8oz per 6qt is maximum effectiveness and you should see results with these ratios. You can add more if you feel you want to make it exact measurements. Capacity of engine oil is roughly 4.5 quarts. Power steering is roughly 1.2 quarts, and transmission is roughly 8-9 quarts. When you drain/refill I would add 1 bottle to last drain/refill, but just adding in you don't want to add too much extra liquid and overfill. Transmission seals are less likely to leak, but do leak, just less likely, so not as important as engine and power steering.
Interval I like to Add once per year with my engine oil. I chance engine oil every Sept. and March 2 times per year. Regardless of miles. I change transmission fluid once every year after initial 3 x Drain/refill once I get my vehicles new. Compared to the 3X drain/refill interval. I add half and half each year. Power steering I change every 3 years along with brake and VTM-4, but I don't use them in those systems. If I ever get a VTM-4 leak which hasn't happened I would put it in there before replacing any seals, but never had an issue, so I'm not going to worry about it. I still only do 1/8 bottle in power steering with fresh fluid through entire system. Coolant I drain/fill radiator every 3 years, and drain the block and all old coolant when I get new to me.
Basically when I get the vehicle new to me, I go through and replace the fluids all fresh so I know they are the correct type, and gives me an idea of the health of the vehicle.
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The sad thing is it used to be $10 at advance auto just a couple years ago. There was a good year or so that it wasn't available on the shelves and had to be special ordered. When it came back it was $20 and now it is $25. I worry it will just keep going up in price, but at least it is available.
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Could be the oil filter housing, pan, or oil pump. I would wait to see if AT-205 fixes it, and if not, pull the wheel off, turn the car on, and look at the housing the oil filter is attached to, sometimes you can literally see it leaking. Will need to replace the gaskets if it doesn't seal.
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If it is coming from the crank pulley area, it is almost a 100% guarantee that you'll have to reseal that oil pump.
There is a ZERO percent chance that AT-205, that is ALWAYS recommended by certain members, is going to help you here.
There are things that it can help with, but not here. Pisses me off every time I see them recommend it for EVERY kind of leak, I assume they are joking, but really gets under my skin.

You'll have to take off the oil filter housing anyways to take it all off, so you'd be replacing that gasket as well, so that whole side of the engine would be sealed up, as you'd be replacing the crank seal as well.
One other thing to look at before you tackle that job, unrelated to your leak, with the engine running, look at the crank pulley while rotating, and see if it wobbles at all, if so the rubber in the crank pulley may be deteriorating, and would need to be replaced. Didn't really notice that with mine until just north of 200k, as you don't want to wrestle with that crank pulley bolt more than once, unless you have the Lisle socket and a good impact wrench.
We recommend to try. We aren't saying it will fix it, but if it does it is better then paying the cost to dig in there. Regardless if it fixes it, the main kicker is that the remaining seals get rejuvenated and may prevent a leak from forming in the future. I hope that clears things up. We have old vehicles, and throwing money at it doesn't always make sense. Some people have basics skills and getting to an oil pump for some is near impossible due to the Crank bolt. Especially if you just got done dumping money into a TB already. Doesn't make sense to spend all that time or money replacing something that could be remedied so easy. I back up my decision to recommend ATP AT-205 to anyone in this situation. If it doesn't work, then they know they need to tear into it. Otherwise why waste all that energy and time? What would be the point?
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Mobil 1 high mileage advanced full synthetic 5w-20.
A step up would be Mobil 1 Ultimate synthetic 5w-20, but you're not going to find it on the shelves.
Honda actually sells Ultimate synthetic 5w-20, but you're going to pay a premium for it.
Pennzoil does make a true synthetic oil, where most other synthetic oils are not actually real synthetic. Most full synthetics are made from crude oil. Pennzoil uses natural gas which is a cleaner base. Pennzoil ultra platinum is supposed to be a real good oil. I just like Mobil 1 because I have history with it, and haven't had issues with it.
Research I have found Mobil 1 may not swell. It uses a thicker base oil to help protect against leaks. " formulated with a higher base oil viscosity to help reduce leaks and provide better high temperature protection" (Mobil 1™ Extended Performance High Mileage 5W-30)
"The function of seal conditioners in ALL of our oils is to keep your soft seals flexible and pliable. This allows them to conform to little surface irregularities and machining imperfections, to keep the oil on the inside. My High Mileage oils contain a slightly higher conditioner content, intended to help if we have a problem seal." (
"I work in the rubber elastomer sealing business, and when I hear seal swelling, I think of a seal that is being compromised, or degraded, and will be failing shortly. In the short run, it may be stopping a leak, as it is filling in a greater area. A torn seal or a worn sealing surface will be fixed temporarily. But the seal will need replacing eventually, and the sealing surface checked for wear. I think it would be unusual for a seal to be exposed to anything in or on an engine to cause it to swell, or degrade, but of course anything can happen. As far as seal conditioning, as has been mentioned with doing an Auto-RX treatment, there is no swelling. Instead, the sludge creating a false seal is cleaned/removed, exposing the actual seal to to the conditioning elements of the oil. It is no longer "drying out", and hardening, from lack of oil. Seals need lubrication as much as bearings. The seal then is able to reconform by returning back to its original softness/hardness. This is a durometer measurement. Now, if the false sludge seal is covering a tear or a damaged or brittle seal, obviously there would be a leak problem. One of the side benefits of some of the products mentioned on this board, in their maintenance doses, is to allow a seal to conform or stay conformed, in additional to keeping things clean." (Seal Swelling vs. Seal Conditioning)
Looks like they don't actually swell the seals. They recondition like at-205, but I wonder if it is the same or different. Appears to have the same effect. With the video below it shows Mobil 1 at least doesn't swell the seals at all. So I would assume these conditioners are not swelling. Although there are some chemicals that do indeed cause swelling, I don't think the engine oils are putting in these chemicals. I have heard brake fluid can swell rubber and has been used to seal engines, but ultimately cause damage if done incorrectly (Left in too long, or put in too much).

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