izzydig

Hey everyone. I have a problem here, and wondering if anyone has seen this type of leak before and could help me...please...

There was smoke the other day on the passenger side, rear of the engine (closest to firewall).

I figured it could be a valve cover gasket, but then I saw a baseball sized puddle of motor oil on the ground (think it drips it out after it gets run...doesn't drip when cold). Tho it seems to be pretty close to the firewall. Looking through the haynes manual, I'm tending to rule out the oil pump, oil pan gasket, crankshaft seal and oil pressure sending unit, but since it's so crammed in there, I can't see for sure where this leak is coming from. I removed all the plastic stuff that is underneath the crankshaft to see better, and I don't think it's coming from the places I just listed above.

Could it be the timing cover? Or is the rear bank valve cover leaking, considering the puddle on the ground is pretty far back towards the firewall? What other places near the rear and passenger side of the engine, could oil be leaking from? I'm hoping a valve cover seal due to the smoke near that area that I noticed yesterday (that seems to be intermittent tho).

Do you all recommend those neon dyes that are thrown in the engine to help pinpoint a leak? How long can dyes be used in the motor oil without much damage if any? Any help would be appreciated!

Thanks,

Isaac

Jeff92se

iTrader: (82)

Put the car on ramps and see where it's coming from

-=PK=-Maxima

ok that wont really work. i have a pretty major oil leak myself and the dealership said it was the timing cover and/or chain. so you might wanna check that out. you might also wanna try that dye thing. go to autozone buy the dye, and put the car on a ramp to clean off EVERYWHERE. i dont think the dye would hurt the engine. plus, the dye would all leak out in a couple of weeks if your leak is as major as mine. a few people on the org suggested i get a new engine instead of getting a new cover and/or chain cause it would cost too much to replace everything. so you might wanna consider that too

Jeff92se

iTrader: (82)

Why wouldn't that work? You should be able to get a general idea where the leak is coming from. If it's that bad, take it to a car wash and clean everything off once and then drive home and put it up on the ramps

Lonely Driver

How come you ruled these out - oil pump, oil pan gasket, crankshaft seal and oil pressure sending unit? Is the puddle under the belt area or more towards the middle of the vehicle?

izzydig

Well I'm going ahead to replace the valve cover gasket on the rear bank. I couldn't find any dye for some reason at a couple of stores here...weird. I couldn't really see the oil dripping down well, but after feeling around, I traced it to the rear valve cover (it was wet on one of the bolts and at the passenger side, firewall seam). This would explain the smoke, as well as cyl #5 spark plug coated in oil (the whole gasket has gotten old). What sucks a lil more is that after checking with my finger under the front bank valve cover, I noticed more wet oil there. The front bank isn't dripping down yet(but is starting to sweat), but I went ahead and ordered gaskets for that as well since that should be really easy compared to the rear valve cover. I attemped to check the seams of the timing cover, and just couldn't feel any grime or oil. I'm really hoping it isn't the timing cover. Though, if it was, I wouldn't have to replace the whole cover (unless it was cracked), just the seal. Though I'd have to take off alot of stuff to completely remove it (major PITA).

Lonely Driver: I ruled out the oil pressure sender, crankshaft and pan gasket, because when I removed the plastic under the car, I could clearly see those seams and gaskets and saw no oil. By the time the oil dripped down, it was away from those areas. I thought I'd make it clear it wasn't those things so nobody misunderstood.

Jeff92se: It's really hard to diagnose this type of leak from underneath the car, since the leak is dripping from higher up and in a hard to see/reach area, and by the time it hits the floor...it has burned up/made a mess etc. I tried...I tried to see clearly.

Well this weekend I'm off the replace them. I ordered today 2 valve cover gaskets (plus 6 oil seals), and a brand new fuel injector to replace one that hiccups occasionally at idle. Should be here tomorrow from courtesy nissan (great prices!). So I get to kill two birds with one stone. Thanks for your all your inputs!

mjc30458

I know what you are going through. I recently replaced the upper and lower pan gasket (RTV, o rings, and "eyebrows"), oil pressure sender, valve cover gaskets (tube seals (6), bolt seals(20), and long rubber gaskets) front and back, intake gaskets, egr gaskets, egr tube gasket(egr tube was completely stuffed full of carbon), and idle (IAC)valve gaskets. phew...

Still leaks oil someware between the valve cover gaskets and upper oil pan. Which only leaves the head gasket(unlikely) and the timing chain rear cover to the block (RTV and o-rings). Also, the little caps that are between the timing chain cover and the valve covers. None of which I think I will want to do. I would rather swap engines than pull the timing assembly apart.

As a note of advice. When you put the tube seals in the valve cover, don't drive them all the way in. Seat them evenly or slightly above the baffle in the valve cover. If you drive them all the way in, they may not seal completely to the spark plug tubes. At least mine did not. So I had to repull the cover and pull them out slightly. Also, in my case they were flipped in opposite directions on the front or rear valve cover. If yours has never been into, you may want to look at them closely and replace them as they were orginally.

I have pressure washed and cleaned and pressure washed and cleaned. Anyway you get the idea. I can't find the leak and I have worked on different cars for over 15 years. I may give in (gasp!) and take it in to be dye tested and get the "final call." Although that is far from an exact science.

Sorry for the rant. I hope this helps.

Mike

izzydig

I'm sorry to hear you haven't been able to trace out that oil leak.

Thank you for the advice on the valve cover gasket as well. Question #1: Regarding the valve cover oil seals...the U of the oil seal points upwards correct? #2: Are the bolt seals rubber? I wasn't aware the bolt seals existed (OEM part #?), and now either have to pick them up locally, or use RTV if possible. Do the bolt seals, mate on top of the valve cover or underneath?

I was looking at the haynes manual, and if you still have a leak...you're right...between the heads and above the upper oil pan seem to be those caps, along with the rear timing cover o-rings. I personally wouldn't mess with them unless the engine was out. In terms of my situation, I know my valve cover is leaking, but is it enough to drip down? If not, I will find out soon enough...but if it isn't and its the head gasket...then I will get a used engine, swap it....then reseal the "spare" engine.

I looked over the procedure to replace the head gasket and my mouth dropped. Yikes. Same or less time to do a full engine swap, with the benefits of a spare engine to work and play with. More money with a used engine, but Nissan had to cram everything in there for a V-6 FWD. Doh. My g/f's mitsubishi head gasket took about 4 hours total(4 cyl, FWD). At the current prices of a used/spare engine ($250-$600), I think it's worth it, but me being a economical...well.

What do you think Mike? Or am being just a wuss about the possible head gasket? Or is taking off the entire timing cover not that hard, but it just takes so long? I dunno. Me thinks about a simple inline 4 sometimes.

mjc30458

Damn, I did a long write up and the BB (or my office LAN) screwed up and I lost it all.

Here we go.

Q #1 answer: I don't know that it really matters, but I put mine in with a solid face towards the head. This way the spark plus tube can slide into the seal without catching on the seal lip (lewed comment is it not). If you flip it over and allow the lip to face down, this could gain you 1/8 in. of sealing depth. This is why I said to look at them closely and replace them as they were in the valve cover.

Q #2: Under the bolt is a metal washer. under the washer there is a rubber seal that is compressed between the washer and the valve cover. They may be so hard that doen't feel like rubber. My Fel-Pro valve gasket kit contained the two gaskets, 6 tube seals, and 20 grommet/seals. Cost $43 Advanced Auto/ Parts America once know as Western Auto. I feel once rubber has be permeated by oil it won't seal affectively or if the rubber is not supple enough to spring back into shape it will leak. I would replace.

My Max runs well enough and leaks less than before. At 267,000 miles I don't think I will be pulling the heads or timing assm.. UET (Used Engine Time) if at all.

Best of luck,

Mike

izzydig

woohoo! Well this last sat. I replaced the two valve cover seals. 90% of the leaks are gone. Now I get a consistent Quarter sized leak on driveway (before it was actually about a volleyball).

I didn't get a chance to purchase the 20 grommet seals for the bolts, because 1, the dealer didn't have 'em (I went OEM), and two, I noticed that they don't really seal. I was using RTV to help seal the old 10 bolt seals on the rear valve cover, and when I was about to RTV seal the front, my friend stopped me. We both noticed that the outer valve cover seal does all the work (+ the inner 3 oil seals). The old seals were pretty rigid and dry, not as malleable as the new ones.

The last quarter sized leak, well, I dunno yet. Could be a few things, but I'm happy I got most of the leak outta the way. I may take it to Pep boys, and for $25 they can run a UV dye, and maybe find this last small leak. If it is coming from the rear timing cover, or head gasket...or other near impossible to reach area, then I'll make fair use of Bar's stop leak (hehe) and get ready for a used engine down the road. It could still be just old run off.

Thanks for all your help!

Lonely Driver

If you take off the passengar wheel and splash guard, you can get a pretty good view of that area where it seems to be leaking.

izzydig

The splash shield is taken off, and didn't think it was leaking from the oil sender or lower oil pan before. Now that I've gotten one leak outta the way (both valve cover gaskets), I'm directing my attention towards the the smaller leaks. Guess what? Today, I cleaned the bottom of my engine out, and noticed my oil sender is sweating where the plastic meets the metal on the oil sender. Also, I noticed a small sweat between the lower oil pan and upper oil pan. I purchased that seal today as well. I knew the valve covers were leaking initially due to the wet oil I was able to touch right on the crevace and below the edge of the valve covers.

Well those two leaks (lower oil and OPS) should take about 45 minutes (including oil change..gotta do it anyway), and hopefully it will take out some of the drippings of my engine.

Lastly...if I have any more leaks, it must either be the upper oil pan or behind the timing cover (I've doublechecked the crackshaft seal...no oil). FU@!%!@%C. I've done some searchs, and found that behind the timing cover(lower), its not too uncommon (just like mjc30458). Ever since I switched to a lighter oil (5-30, b4 10-30) and the weather has changed...I exposed all old seals...bah. I'm sure the cold doesn't help rubber seal, and lighter oil tends to flow easier past old seals. Oh well, the good news today is that Saddam got captured! woohoo!

I will have to do these two leaks sometime this week. Thanks.

matty

iTrader: (54)

You meen changing to lighter oil from 10W-30 to 5W-30 for the winter could actually affect the seals enough to make tke care leak Motor Oil ?? sounds fishy

-matt

gtr_rider

iTrader: (50)

I didnt read all that writing above, but, when I thought I had an oil leak and I had the same smoke coming from the rear passenger side of the engine bay. It turned out that my power steering tube was lose, and power steering fluid was leaking down from the tube and hitting the exhaust pipe and making the smoke. It also looked like a puddle of oil on the ground, but didnt smell like it when I ran my finger through it and smelt it, just a FYI post.

izzydig

LMAO-gtr_rider...never seen someone with so many posts(10K). Wow! First time for everything...I've only been on the org for 8-9 months.

I know I do have a small PS leak, and it appears to be a hose that connects directly to the PS pump (not worried too much...as I have to add about 1 oz every month). Tho, the smoking oil has gone away (previously, from the valve cover...motor oil would leak onto the ypipe...and that thing is hot!...hence some smoking). Thanks for the info tho. I wish I knew where else PS fluid could be leaking from, with clampable hoses. I read a TSB for 97-99's where nissan didn't tighten some clamps on PS hoses enough. Any ideas? Or better...pics? I've doublechecked the hoses for PS on top of the engine (off of reservoir), and found no leak.

Matt: I guarantee if I use straight 50 weight oil...My leaks will stop...my compression will go up, and I will eventually blow some other seals on my engine in the winter and/or summer (thats all an extreme example of course). Oil Weight does affect the seals ability to seal. I think the combo betweem thinner oil...cold weather...and of course....OLD seals: the VQ30 has started to leak on me. I have 227.5K miles on her. I've only ever used 10-30 anyway, since I live in the desert. ...But since I'm going north for the winter, I decided to play it safe with weight...doh. Granted...5-30 vs 10-30 isn't a whole lotta diff, but it won't help. Don't mean to b itch, just FYI in case u already didn't know.

Thanks.
-Isaac