1991 Q45a Oil Leak

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

This was what the oil pump sprocket and nut looked like once the cover was off. The nut is hanging on there by a few threads. The sprocket, oil pump and chain still move as one unit. This may debunk the idea that something jammed in the oil pump. Is the shaft keyed? Maybe the nut worked itself loose over time and backed off when it finally contacted the cover. (That makes more sense to me.) Opinions?

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

It doesn't end there. One broken chain guide found. The slack-side, passenger side snapped in two with a big chunk of the center missing. The driver's slack-side is intact and in good shape. Both tension guides look like they are metal-backed to me. They are one-piece of thick metal with a plastic face attached. Are these the old or upgraded guides? They look to be in very good condition.

Is it possible that someone changed the guides previously? Blue RTV was found on the timing chain covers. Someone please let me know if these are the new or old-style guides!

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

Here's a photo showing the loose nut, the amount of slack in the oil pump chain, and one of the tension side chain guides.

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

Here's a better shot of that chain guide from a different angle.

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

Aha! The digital camera goes where no other man has gone before. I found this piece of chain guide after reviewing these photos again. I almost missed it.

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

So, there you have it. That's what a chain guide failure looks like if you are very, very lucky. :ylsuper As I mentioned previously, the engine was running fine after the cracked cover was found. I do need some professional advice ASAP regarding the status of the tension-side guides though. I'll be ordering replacement parts on Monday.

By the way, I found a used lower cover for $25 + shipping from eBay. What incredible "timing"...

AZSKYGOD

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

I'm not at home right now, so I can't check my old guides form "Q2" but from what I remember, the tension side guides didn't change with the update, only the slack side guides. With the updated style they're all metal backed. It wouldn't surprise me if some debris got wedged in there holding the nut between the cover and allowing the oil pump to continue to spin and start the nut backing off. Hard to explain, but in any case you're very lucky! I'll check my old guides when I get back to Columbia and let you know what I find!

Did you find the metal "ear" from the cover? Try to find all of the old guide peices or you'll need to figure out how to pull the oil pan too.

As far as professional advice... I'm not a professional, but I watched one at T3 last fall - they replace all four guides, the oil chain, oil chain guide, tensioners, and front main seal. I beleive they've seen one situation on a high mileage 94+ Q where the plastic came detached from the metal backing - so you'll really want to repalce them all while you're in there.

Heath

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

You are the luckiest guy--would you please send me winning numbers for Texas lottery? You are also to be commended for the dilligence and persistence in searching for the unusual oil leak. A few more revolutions may have been the end. Sharp Eyes!!

Post by **SOCAL91Q45a** » Mon Dec 29, 2003 8:08 pm

Azsky - man sorry to hear of your troubles. But want to also commend and thank you for the photos and diligence.

This begs a question ... I thought the 94+ motors were immune to such guide failures? Plastic guides in a 94?

Is there a way to see/check what style guides are in the motor without removing the front timing chain cover?

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

Actually this is a 91. There is only one way I can think of to check what type of guides you might have without removing the lower cover. It would involve removing the passenger side tensioner cover and sticking a flexible boroscope in there. Very close quarters if the radiator, belts, etc. are left in place though. Just a thought.

By the way, I would encourage those of you who are considering a DIY chain guide replacement to go for it! I an NOT a mechanic, in fact, I'm just a fearless (skydiving) network administrator who knows how to use a socket wrench and a digital camera. None of the work is very difficult, just time consuming. While it appears this thread has gone on for a month, the amount of time I spent actually taking stuff apart was about 4 hours. Most of my time between was spent locating and waiting for parts and tools to arrive.

Long live the Death Machine!

AZSKYGOD

Post by **SOCAL91Q45a** » Mon Dec 29, 2003 8:08 pm

Thats the spirit!!! Hehehe I love it.

Im not a mechanic either, I just play one on weekends w/ Mustangs :-)

My motor is already out of the car. Perhaps I can compare serial / part numbers.

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

Even the new guides that are metal backed have the plastic coating. Apparently on that one case that I've heard of - the plastic came apart from the metal backing. I wouldn't be concerned about it as a general rule.

azskygod - I was thinking with the mileage on your motor, you might seriously consider replacing the chains too. You'll have to remove the rocker covers and re-time, but with that kind of mileage, it would be the safe way to go. I'm sure Q45Tech will come along eventually and give his take on all of this. I just remember him mentioning once that if he knew that he'd be able to get 300K+ miles out of the engine he'd probably have replaced the chains with the guides at 100K. Of course with all of this you have to take into account the overall health of the engine - were you having any oil consumption or smoking yet?

Heath

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

Yes, there's a little bit of smoke after about 5 minutes of idling, but none otherwise. I think it's sucking some oil past the valve guides. It consumes about a quart a month, but to put that in perspective I usually drive about 500 highway miles per week. I considered replacing the timing chains, but I probably won't since it hasn't jumped time. Besides, if I'm going to remove the valve covers I might as well replace the valve guides too, right? I have to draw the line somewhere so I can get back on the road.

AZSKYGOD

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

Chains yes, valve guides would be a much more involved project requiring a bench and precision tools.

Post by **90Q45blue** » Mon Dec 29, 2003 8:08 pm

Since you are replacing the guides and the chains are right there, you should be able to see how much they have stretched in 13 years, 214,000 miles. If they seem fine, I don't think I would worry too much about it. But it's like Heath said, it depends on how long you want to keep the car.

Nick

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

The FSM says there are valve guide seals! Can these be replaced without removing the heads, and would that solve my oil burning? Maybe another project for another day.

I finally ordered my parts today. $382 includes all chain guides and bolts, oil pump chain, crankshaft seal, radiator hoses, front brake pads, 3 liters of Active-A, tax & shipping. Thanks again, Joe!

I'm going "fishing" for guide pieces tomorrow night. I think the big chunk in that last photo is the broken guide. The only other missing piece is that metal tab (ear) from the cover. I've got one of those flexible wire claw things and a magnetic one too. No good for aluminum, but who knows what else I'll find in there. Any suggestions?

AZSKYGOD

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

Q451990 wrote:I'm not at home right now, so I can't check my old guides form "Q2" but from what I remember, the tension side guides didn't change with the update, only the slack side guides. With the updated style they're all metal backed.

I got back to icy cold Columbia this afternoon and finally checked the old guides from "Q2" and I was right. The OEM guides were metal backed on the tension side, and all plastic on the slack side.

Heath

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

The stem seals can be replaced on the car to the best of my knowledge. BUT that's assuming you can find a tool to install the valve springs and retainers. I haven't found one yet locally that can do it with the heads on. However, the manual does list such a tool by number, so maybe Joe can order one for you. As far as whether it would solve your oil loss, it could, but the loss may be due to a bad oil ring too. Have you tried running a thicker oil?

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

Well, the Death Machine is back in one piece again but maybe not for long. I fired it up yesterday, and it's making a horrendous noise and stumbling badly. I shut it down after about 15 seconds and tried it again a few minutes later with the same results. I searched the posts here, and found that Q45Tech made the following comment in another thread:

Quote »Be prepared for the horrendous noise that happens till the HLA and tensioners pump up! Run a second turn off run a second turn off 2-3-4 times the noise will stop.[/quote]I'm going to make another attempt tonight, but I just want to make sure that what I'm hearing is normal. The sounds are absolutely, positively sick. Lots of loud rattling and clattering, and the engine is barely running. I did not replace the chains or retime, and I made sure to hand-crank the engine to check for interference before reassembly. I did change the oil and refill with 20w50. I wonder if that could be part of the problem? HELP! :help

More photos soon...

AZSKYGOD

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

Hope it all comes together. If you're going to be cranking it a lot to build up oil pressure, pull the injectors and fuel pump fuses first. Check the oil pressure ASAP to make sure the new pump is doing its job.

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

I've done two chain guides so far, on 1990's, and all the guides were plastic through and through. -Squee

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

The noise is normal, but the stumbling scares me. Is it possible that it jumped time one tooth? I think that would explain the stumbling. Other possibilities include a bad electrical connection somewhere (MAF or CAS) but I'd sure be careful running it too much if the engine is stumbling.

Heath

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

You did torque the cranksaft bolt up to 270 ft-lbs, right?

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

Did you also unlatch the little "keeper hook" (or whatever you call it??) for the passenger side tensioner. A rattling chain would make a terrible noise, and mine did for the first post chain guide startup. Check the MAF for the stumbling. Doug

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

Heath, I doubt it's the MAF or CAS. The MAF has the ground wire fix. Never touched the CAS, so it should be dead on. Daedalus, I pulled the injector harness connector and the fuel pump fuse tonight and started cranking. 10 second crank then 10 second pause, repeated 10 times total. I reconnected the injector harness, replaced the fuse, crossed my fingers and started it.

The clatter was a little quieter, but that's not saying much. It's still pretty freaking loud -- it sounds like a diesel engine! So I tried Q45Tech's method of start, wait 1 second then stop, repeated 3 or 4 times. (I found it while searching for help.) It seemed to idle more smoothly after that, but still stumbles and will eventaully stall if left untouched. The noise persists and is definitely coming from the driver's side valve cover.

I'm going to post an AVI of the engine starting and running at ftp://69.26.192.114/MVI_0493.AVI. It's a fast download, about 4MB and 15 seconds long. Notice the strange, uneven cranking sounds before it finally starts. No, that's not your computer stuttering. (Crank up the volume until it totally freaks you out.) Once again... HELP!

AZSKYGOD

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

Oops, I left some questions unanswered.

Yes, the keeper hook on the passenger side tensioner was unlatched but the passenger side seems to be OK. No noises. The crankshaft bolt was torqued by hand with a chain wrench on the frame and a 28-inch breaker bar, and I put at least twice as much force and effort into tightening it than I did removing it. (1 person to remove, 2 to torque.) The oil pump was not replaced. The engine was cranked by hand with no interference.

Thanks guys. I'm going to go have some nice Q45 nightmares now, and I'll check back in the morning. I need my rest. It looks like another long weekend under the hood. Bleh.

AZSKYGOD

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

I had a very similar experience, with a very similar soundtrack. It was after doing a chain guide job. Tore the car apart (again) and, after lots of inspection and finally some consultation with Joe at Scottsdale, I tracked the problem down to gunk in the tensioner oil port. It didn't sound quite as bad as yours, which makes me wonder if the oil pump is putting out pressure at all. There's some terrible energy and damage done there, and I would be surprised if it was limited to your front cover. The oil pump is my first guess, and measure your oil pressure ASAP to see if you need to open it up again. If the pressure is good, then you'll need to look at the tensioners again.

Post by **TorQue45** » Mon Dec 29, 2003 8:08 pm

Wish I can help you

Hang it in there azskygod.

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

Thanks for the reassuring words, Daedalus. I will check the oil pressure this weekend, remove and check out the driver's side tensioner too. If that doesn't work, I'm going to disassemble everything again and retime.

I'm kind of surprised Q45Tech hasn't enlightened this thread yet...

AZSKYGOD

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

He has several times recommended that only experienced techs tackle this job. I marvel at my luck doing it myself.

1991 Q45a Oil Leak

Lucky!!

Horrendous Noise

Link to AVI

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