1991 Q45a Oil Leak

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

What a mess! I've got an oil leak somewhere... Here are the facts:

1991 Q45a, 214k miles. New DIY plenum rubber and bench tested old injectors 4 months ago. Running fine until last weekend. 5k on existing oil and filter. Topped off 1 quart of 20w50. Started normally (no noises), drove 1 mile and stopped for fuel. On restart, engine cranked slow and hard one revolution, then started. Persistent valve clatter and pinging on accelleration afterwards. Slight power loss. Drove home and parked. Next day, started and drove normally with absolutely no noises or power loss. Noticed slight oil leak and parked again overnight. Following morning, large oil stain on driveway. Oil level is not readable, but it was full 5 days ago! Major oil leak coming from front of engine and everything below the pan gasket seems wet. No valve cover leaks. No oil filter leaks. Top of engine is dry. Haven't checked coolant for oil... yet.

I hope that's enough information. What I want to know is, where could the oil be coming from? I will take the Q to the wash this weekend to clean the underbody, refill with oil and watch for leaks. As you can see, there are a bunch of hoses next to the power steering pump that seem suspect, but I don't think engine oil pumps through any of these. What should I be looking for?

Thanks in advance. Enjoy the photos. Sharp eyes will notice small amounts of green Active-A and red power steering fluid weeping from the PS pump too. Help!

AZSKYGOD

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

More photos...

Post by **Q451990** » Mon Dec 29, 2003 8:08 pm

Looks bad! Maybe a bad front main seal??? Unusual for a leak to start "all of the sudden" like that, but given the amount of dirt in the residue, I'd say it's been there for a while...

Heath

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

During cranking, it felt like there was a buildup of back pressure and then something burst. Is that possible if the oil filter was clogged? I suspect the main seal too, but I don't know enough about the engine internals to make an educated guess.

Do any of the hoses carry engine oil? Anyone else DIY the main seal before and how much work is involved? Thanks.

AZSKYGOD

Post by **PalmerWMD** » Mon Dec 29, 2003 8:08 pm

azskygod wrote:During cranking, it felt like there was a buildup of back pressure and then something burst. Is that possible if the oil filter was clogged? I suspect the main seal too, but I don't know enough about the engine internals to make an educated guess.

Yes oil filters do burst on occasion especially if you runa thicker oil in winter and if teh oil filter is cheap.

Still rare, so likely not the cause ,but its an easy+ cheap check.

Fred...

Post by **911/Q45** » Mon Dec 29, 2003 8:08 pm

Have the guides been replaced? You're most of the way there when you replace the front seal. I wonder if it's possible that a partial guide failure could be responsible for your cranking problem and oil leak? The toughest part of the front seal is R&R of the 270ftlb crankshaft pulley bolt.

Post by **fxjackso** » Mon Dec 29, 2003 8:08 pm

I have also found that some filters, and in particular I mention the PureOne, have a so-so fit. When I used them, I would think they were sealed, then after a while they would start to leak. Nothing to rival what you are describing here. I'm among those who suspect the seall.

The other hoses are either steering or active. I have had a few steering leaks, but never an active leak.

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Can anyone identify the hoses indicated by the red arrows in the photos? That would help a little. They are literally "hosed" with oil. Thanks.

Post by **Q451990** » Mon Dec 29, 2003 8:08 pm

azskygod wrote:Can anyone identify the hoses indicated by the red arrows in the photos? That would help a little. They are literally "hosed" with oil. Thanks.

If I'm looking at the picture correctly, the two with the hose clamps are your transmission cooler lines. The one with the large bolt is a high pressure power steering line.

I think you're on the right track to completely clean the engine and then start looking for the leak.

Heath

Post by **DougQ45** » Mon Dec 29, 2003 8:08 pm

Heath is correct on the hoses. The tranny lines are the small ones, and the "drivers" side is from the tranny pump and supplies the fluid, the "passenger" side is the return line to the tranny. If you ever want to check your trans cooler & pump operation, disconnect the "return" line and put a large glass jar under the line, then have an assistant start the car just for a second----boy does it squirt fluid!!

The large diameter hose is the power steering hose, and if I recall correctly about $160!!!!

Post by **squeefoo** » Mon Dec 29, 2003 8:08 pm

Guys ---take off the hose and have a new hose crimped on.(make sure the ends are oriented properly) Save yourself about $130.00 - then take off the reservoir return line and purge to a bucket while you pour in fresh Mobil1 ATF Your Q will thank you!Squee

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Well, I cleaned the Death Machine today and found the cause of my oil leak. I was totally shocked when I saw this. Check it out.

The cover is cracked right where the bulge is for the oil pump, right? The photo shows the power steering pulley on the right, the crankshaft pulley on the left, and the tensioner above.

How is this possible? Broken oil chain guide? Maybe something got stuck in and seized the oil pump, and the sprocket nut backed itself off enough to crack the cover? I'm stumped.

Has anyone ever seen this kind of damage before?

AZSKYGOD

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

More Awww Crap Photos...

Post by **AZhitman** » Mon Dec 29, 2003 8:08 pm

Let me know if you need any local help....

Post by **Q451990** » Mon Dec 29, 2003 8:08 pm

Wow... never heard of that before? Were your guides replaced? In any case I'd have it towed, not drive it to wherever is going to do the work!

Heath

Post by **911/Q45** » Mon Dec 29, 2003 8:08 pm

If the guides haven't been replaced, then a piece of broken guide got into the oil pump drive and you're really lucky to still have a running engine. If the guides have been replaced, then the tech didn't torque the crank bolt enough and you're really unlucky. Ditto Q451990 and have it towed if you're not DIY capable.

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Thanks for the replies. I have to agree with 911 and Heath. As far as I know, the guides were never replaced. Sounds like one of them lunched during startup cranking, got stuck between the chain and the oil pump sprocket, then cracked the cover.

It was driven a few short trips before I found the crack, but the engine still runs strong and noise free. I've been extremely lucky so far. It's parked now until I can repair it... Again.

Is this a DIY (in my garage) kind of job? I finished a complete under-plenum overhaul about 4 months ago. Lots of labor, but nothing too difficult. I'm concerned about the oil pan. I'm sure I can pull off the rest, but the R&R of the pan sounds like a huge PITA. Any suggestions?

AZSKYGOD

Post by **DAEDALUS** » Mon Dec 29, 2003 8:08 pm

Depends on what's wrong. It's DIY to open up the front cover at least. The guide might still be there, maybe too big a piece to fall down. Probably shattered though if I had to guess. You can get another cover at a wrecking yard. I can't believe the amount of energy involved to shatter that casting. Looks like you got really lucky, all things considered. Better a spat guide than jumped timing!

Post by **911/Q45** » Mon Dec 29, 2003 8:08 pm

Give DIY a try, you're up to it if you did the plenum removal. Worst case: If you get in over your head, you have it towed somewhere, which you would do anyway.

Post by **squeefoo** » Mon Dec 29, 2003 8:08 pm

AZ Sky--- Draw a map of the cover once you get it bare, then add the bolt holes, and as you remove the bolts, write down the bolt length to the corresponding hole ....and voila. If memory serves me correct, there are 6 different lengths and 32 bolt holes; or more than 192 ways to put those bolts in the wrong (ALUMINUM!!) hole. Squee

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Good advice. Lots of digital photos will help too. It's finally up on jackstands in the garage now. Drained the radiator Sunday and will spend a few evenings removing the radiator, fan, belts and tensioners. At least it's cool outside. It could be worse... It could be SUMMER! Disassembly seems easy enough, but I know that crankshaft pulley bolt is just going to be a ****** to R&R.

Spent a whole day just staring at it, trying to decide if it was worth repairing or trading up. 214k is a lot of miles! Can I get 300k out of it? It definitely was a turning point. Kinda like the plenum job. Good thing I had a FSM to flip through. They make it look so EASY! Well, I'm committed again. I must be crazy.

I'm ordering parts (minus chains) from Joe this week, but I'm having a hard time finding a used lower chain cover. Is anyone parting out an engine? I'd hate to get all the work done this weekend and not be able to button it up...

AZSKYGOD

Post by **Q451990** » Mon Dec 29, 2003 8:08 pm

After thinking about this crack again, I think that the "ear" that sticks out of the engine cover between the oil chain that usually breaks off during a guide failure, must have broken through the cover instead.

I'd call Joe and see if they have any old engines laying around the shop from guide failures... Not sure how much a new one would cost. There's a Q here in SC with the engine still in it, but it's one of those u-pick, u-pull places so that's not much help. http://www.autogator.com may be another good source.

After watching Byron do mine at T3, I think it's DIY-able, but it'll be a bear. If you have a digital camera take pictures and post them here. One thing I remember is Byron taking the pulley off of the p/s pump. You'll need a good chain wrench and puller for the pulley, but I think you can do it.

There's always a good chance you can fish the guide peices out of the pan if they're still intact. Make sure you replace the oil chain and guide and tensioners.

You're one of the luckiest guide failure cases I've heard of... no point in giving up on the car now! Just think, two months of payments on a new Q or M, and you'd be back to your parts cost.

Heath

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Ya, Heath, I'm kinda curious to see what happened in there too. I'll follow up with some photos of the carnage once I get the cover off. This should get interesting real soon. Stay tuned.

AZSKYGOD

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

It always surprises me how quickly things come apart once the wrench starts turning and the first bolt is removed. Check out this photo of the crack in the lower timing chain cover. It's much bigger than I thought and almost forms a complete circle around the oil pump...

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

... And what is this allen-head bolt doing here next to the crankshaft pulley bolt?

Post by **squeefoo** » Mon Dec 29, 2003 8:08 pm

What I did was cut a section of serp belt to cover the ribs on the pulley and to give it some "bite" when using the chain wrench. Don't remember what that allen does, its been a couple of years. Squee

Edited by DAEDALUS on 1/10/04.

Post by **DAEDALUS** » Mon Dec 29, 2003 8:08 pm

Azskygod, not sure what that one bolt is for, but you can leave them all in. They're weights only for balance, and don't fasten anything.

Squee, do NOT put a chain wrench on the pulley and tap the starter. The pulley and the crankshaft turn together, and the crankshaft turns with the starter. By locking one, something will break. I think you mean to put a wrench on the bolt, rest the handle against solid structure (noting direction of rotation), and tap the starter.

Post by **squeefoo** » Mon Dec 29, 2003 8:08 pm

Yes; that's what I meant, I must not have been clear enough. The chain wrench is for holding the pulley to tighten the bolt, the serp belt piece keeps the ribs from getting gouged, the starter is to loosen the bolt, if the direction works out - as a last resort- IF ALL ELSE FAILS. -Squee

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

I take it all back. Removing the crankshaft pulley bolt isn't nearly as difficult as removing the lower timing chain cover. Especially when you forget to remove the 4 bolts on the oil pan first. :rolleyes Anyway, the folowing photos should really fuel the speculation about what happened to my chain guides.

Upon removal, I noticed the inside of the cover showed a ring where the oil pump pulley nut made contact. Did something jam the oil pump, allowing the sprocket and nut to back off and crack the cover? (The oil pump rotates freely by hand now.)

Post by **azskygod** » Mon Dec 29, 2003 8:08 pm

Heath was correct in speculating that the metal tab (ear) on the inside of the lower cover broke off. Here's the proof.