L05 Issue Speculation

Let's mix it up a bit and try to solve a problem somewhat backwards.   

I pulled my valve covers for the first time since I purchased my OCC in '01. The drainback holes at the ends of the heads were 90-100% plugged with crap. The two larger cavities at the top of the heads are still open to the lifter galley.

Here's the speculation part. What symptoms do you think this may cause?

If the oil was not allowed to circulate correctly, some parts are not being lubricated. Your engine may have run noisily . You may not have had good oil pressure. If the drainback holes were plugged, you may have problems other places, such as the oil pump screen being plugged.

Seeing you have owned the wagon since 01, how often do you change the oil?

Tom

The oil has been changed every 3000-4000 miles; first with Castrol GTX and for the last several years, Castrol High mileage. Admittedly, the PCV system got away from me and about a year ago I was checking the oil and the dipstick had lots of condensation and white goop on it up over the oil level. 

I replaced the PCV valve and did a Seafoam treatment and that cleaned right up.

As for how it's currently operating: Oil pressure is actually stellar according to the stock gage. Warmed up going down the road it reads in the 45-55 psi range. The engine purrs with no noises or hiccups, starts right away every time, still has good power, runs cool, doesn't use oil and gets decent mileage.

I just recently took a road trip from Memphis to Chattanooga to Nashville and back and it did great. Went to NJ and back last Summer.

But...I am now chasing something that recently cropped up.

What are you chasing?

Greg:

You may still have an issue with the PCV system.  Had an L03 go the same way, with the same symptoms.  Turned out the PCV port in the throttle body was plugged up.  Had to remove the TB and clean it out on the bench it was so bad. The port was still partially functioning as the normal vacuum test on the valve indicated that it was good, it just wasn't flowing the way it should.  Took me awhile to track down the problem.

The choice of oil is one of the topics that has been discussed ad nauseatum in virtually all car and truck forums with the consensus being it is up to personal preference.  However, and granted the formulations have no doubt changed over the years, I stopped using Castrol over 35 years ago for exactly the same situation that you now have under your valve covers, high sludge buildup. Used to use it in my British motorcycles and sports cars. At the time, I switched over to Quakerstate and almost immediately the sludge and varnish disappeared.  Never used Castrol again.  

After experiencing Synthetics in the aircraft game, have been using them exclusively whenever I could get them.  Mobile 1 seems to be the preferred choice but expect any of them would be better than conventional oils.  Only exception seems to be in diesel engines.  Experience with synthetics in diesels seems to be all over the map.  Personally I use 15-40 Rotella conventional in the diesel and Mobile 1 in the gassers and have not had an issue.

Hope this helps

Bill

I'll guess your new symptom is smoke on deceleration.

Okay, I'll end the drama. My issue, which just began this week, is that when I completely lift off the throttle after driving a small distance, the car unleashes a smoke cloud big enough to reduce the mosquito population. It only happens in this maximum vacuum situation. As soon as I touch the gas again, the smoke stops.

The thought is that the valve area is drowning in oil that cant drain and it's getting sucked into the combustion chamber under high vacuum.

I'm getting a very strong vacuum at PCV. By the way, the debris seems to be older, baked sludge as it's hard and flaky. There is no gooey slugde in there.

jayoldschool wrote:

I'll guess your new symptom is smoke on deceleration.

We have a winner! You guessed it while I was typing. Seen it before?

Yep, out the tailpipe of my 65 Impala.

put some valve seals on it,.
use the ford umbrella type,. it'll be fine,.

run dino oil in an older engine,.

and change the pcv valve again,.make sure it has the splash shield inside the cover,.

did you clean out the drain back holes?

Yes, the stock valve covers have the internal baffles for the PVC and vent. I do have a spare, new PCV that I can install.

I was only able to remove the valve covers last night before it got too late. This weekend I'll get things cleaned out and see where I'm at. I figure a scribe and the shop vac should work well in cleaning the hubris.

Olds Weighty Eight wrote:

The thought is that the valve area is drowning in oil that cant drain and it's getting sucked into the combustion chamber under high vacuum.

I'm getting a very strong vacuum at PCV. By the way, the debris seems to be older, baked sludge as it's hard and flaky. There is no gooey slugde in there.

Your right on. Get the oil to drain back properly and the valve seal issue will probably disappear. Did on mine. Even the best valve seal doesn't work when its submerged.

Gooey sludge turns into hard sludge with age. Again check the throttle body. My PCV still had great vacuum but the hardened carbon deposits in the throttle body was restricting the flow. Worth checking as the whole job took less than 1/2 hour and totally rectified the situation.

Bill

Olds Weighty Eight wrote:

I figure a scribe and the shop vac should work well in cleaning the hubris.

Not sure how much HUBRIS is in a tbi motor,.but i,m sure it makes them even slower,..

clean the drain back holes with a battery powered drill,.and the shop vac,

Well Nick, looks like valve seals are next. I cleaned everything out including the PCV port, replaced the 3/8 PCV hose as it was starting to crack and buttoned things back up.

The problem persists.  

With that mileage you may need guides too,it is a small block chevy after all!

Yeah, it's more like a can of worms at this point.

So if I'm going to rip the heads off to have them freshened up, should I just pull the entire engine and go through it? Or a crate motor, or...?  

Dammit, I paid $2850 for this car in 2001. Did I get my money's worth out of it?  

You should buy my vortec heads I have sitting here and call it a day. :p

Disclaimer: You'd need a new intake.

If the bottom end is good,Rays heads would be the cheapest route plus a little power boost is a plus.You,ve had your wagon 3 years longer than me and I just cant imagine not having mine after 10 years.

just pull the springs , add new ones and some seals,. call it a day,..

but first,..

pull the pcv,. plug the vacuum leak,. leave the oil cap off,.drive it,.

report back,.

phantom 309 wrote:

just pull the springs , add new ones and some seals,. call it a day,..

but first,..

pull the pcv,. plug the vacuum leak,. leave the oil cap off,.drive it,.

report back,.

Agreed. Takes the PCV out of the equation. You might just on spec, replace the PCV valve again.

Bill

I'll try the PCV elimination test Tuesday after work. This afternoon was full of thunderstorms and lots of rain.

Well, it's still smoking with either a new PCV valve or the PCV system removed entirely with the valve covers open to atmosphere.  

Get a vacuum gauge and learn how to read it,it will tell you more about your engine than any computer.Thinking you have a crack somewhere in your head or cylinder and its sucking coolant into the combustion chamber when you decelerate.The vacuum gauge is a wonder tool from the 1900s that still wotks with any internal combustion engine.

Sure doesn't smell like coolant and the level in the overflow hasn't varied a mm.

I run a combo vacuum/boost gauge on my GN so I'm familiar with one. I recall the gauge on my first GN telling me that the cam was losing a lobe back in the '90s. Not sure how one would indicate a crack like you describe though.

Olds Weighty Eight wrote:

Sure doesn't smell like coolant and the level in the overflow hasn't varied a mm.

I run a combo vacuum/boost gauge on my GN so I'm familiar with one. I recall the gauge on my first GN telling me that the cam was losing a lobe back in the '90s. Not sure how one would indicate a crack like you describe though.

Let me find my old Chiltons manual from the 70s,it has a 5 or 6 page section about reading the gauges needle movement!

there's only one cracked head in this thread,..

put some valve seals on it,..  keep driving,. add oil as necessary,. use a lighter weight oil,.its easier for the old rings to scrape off,.

break off rear view mirror and discard.

or check out a brand new goodwrench motor for about 1800,..12568758

phantom 309 wrote:

break off rear view mirror and discard.

  Genius! It's all fixed now.
Trouble is I keep getting lost without my digital compass.   

I'm going to go the valve seal route next, thanks.

Quote :

break off rear view mirror and discard

The first rule of Italian driving!

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Well, I finally had some time today to look into this some more after travelling the past couple weeks. I pulled all the plugs for inspection and performed a compression test. Here's the results:

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That #7 plug was torqued fairly loose as well; came out real easy. A buddy suspects a worn valve guide on that hole. Thoughts?

see above posts regarding valve seals,.

If you are going to take the heads off, you might as well go through the lower end. It could even be a cracked ring, or two. If it happened suddenly, a small part catastrophically failing would be suspect.

Did you check the effect of the gold paint?

How many miles have you put on the car since you got it. At $.10 per mile, it does not owe you anything.

put in my 2 cents, talking about the white goo earlier on, coolant getting in the oil? (sounds like a blown head gasket?) white cloud when releasing the throttle? (as you said)

Heads aren't off quite yet. I've got a valve spring removal tool on the way so I can assess the valve seals first and get a feel for the condition of the valve guides too. Obviously, cylinder #7 is highly suspect so it'll get the most scrutiny. 

Fred, I went back and looked at the paperwork from when I bought the car in '01 for $2850. It already had 172,000 at that time; more than I recalled. Anyway, it's at 271,000 now so it doesn't owe me a thing as you said. That's three cents per mile based on purchase price. Furthermore, it's still in such great condition that it will be repaired and returned to the road. 

Even if I wind up rebuilding/replacing the engine, I'd be hard pressed to get anything else as solid and useful as this wagon for what I'll spend on repairs. Meanwhile, my Cutlass is getting some much needed daily-driver excersize.

Mystery solved...and nobody guessed it.    

In preparation for removing the valve springs on #7 cylinder (starting there since that plug was so oily), I put pressurized air to the cylinder. It immediately began blowing oil bubbles in the rear corner of the head. WTF?

Broken head bolt.   I just plucked it right out of there.

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That certainly explains the sudden onset of the problem and why it started weeping oil out around the fill cap and PCV grommet when driven.

I will have to check my head bolts. I have the weeping issue, but not the smoke. I will pull the plugs to check them first. Incredible find. It is hard to believe that a head bolt broke off.

Messed around a few hours with drill bits and bolt extractors to no avail so I am resigned to pulling the head at this point. Reminds me why I like Buick engines better with the front-mounted distributor that doesn't go through the intake manifold. I look forward to this job.  

Surprised you had 180 pounds on the compression test of #7.

Distributor isn't hard to pull from these cars. Comes out between the throttle cables and brake booster.

Yep. Remove cap and rotor for clearance, pull up, angle to driver's side, and out she comes.


Can't wait til I never have to do THAT again.

(In before Nick makes a firing order joke. :p )

Forgot about having to pull the cap and rotor. You need every MM of clearance you can get!

I had the same issue with both my 305 LO3s I've owned. WOT runs on the expressway entrance ramps would make my oil light flicker. If I remember correctly Fred (Ruphraxe) told me that that was an issue with the LO3s, but not the LO5s. Doesn't seem logical that the 305s had this issue, and the 350s didn't but the one 350 I had never had this issue. Anyway, I cleaned the oil drain back holes just as Nick has said, and cleaned the pcv system as Bill has said.... And you've got to clean the port on the intake. This helped immensely, but never cured the smoking issue completely. I never put valve seals on them as they were throw away winter rats.

Never mind.... I somehow missed reading the second half of page 2.  

Sometimes you can do it with the rotor on, but really, just pull the damn thing it takes two seconds.

Stingroo wrote:

Yep. Remove cap and rotor for clearance, pull up, angle to driver's side, and out she comes.


Can't wait til I never have to do THAT again.

(In before Nick makes a firing order joke. :p )

Quit the bragging Ray,what about all the gas and tire rubber that you will be using with all that extra power? 

Finally got everything pulled down on the OCC in order to fix the broken head bolt. Now the real fun begins not only getting the remnants of the head bolt out of the block but I also had to remove the alternator bracket from the front of the head with a hacksaw! 

I curse the engineer that spec'd T45 button-head cap screws to hold that accessory bracket to the head! Of course the Torx bit breaks off inside the head of the completely obscured bolt. After molesting the damn thing with punches and chisels with no results, out came the hacksaw. Now I need to get the rest of that bolt out of the head too.

shitty chinese torx bit,...

If i know the torx is going to strip,. i stop,. and whack the sh1t outta the head of the bolt,. then tap the bit into it,. then whack the bit as hard as i can, with as heavy a hammer as i have,.

you need to learn when things are going to strip,.... to stop,.

is this motor worth the time?

lots of craigslist motors out there,.

I'm not giving up just yet. Hell, I'm almost there at this point.

I do know the old hammer trick as I had to employ it Saturday to remove the Thunderbird brake caliper T40 bolts. The OCC, on the other hand, felt like the bolt broke loose and started to turn when it was in fact the bit failing. Fooled me. 

Yeah, cheap China ****...my bad on that. Up until now the only thing I had used the T45 for was my G-body calipers.

Olds Weighty Eight wrote:

I do know the old hammer trick as I had to employ it Saturday to remove the Thunderbird brake caliper T40 bolts. The OCC, on the other hand, felt like the bolt broke loose and started to turn when it was in fact the bit failing. Fooled me. 

Yeah, cheap China ****...my bad on that. Up until now the only thing I had used the T45 for was my G-body calipers.

I didn't mean to sound like i had all the answers,. which i do,. but i have never been fooled by a shitty torx bit,
and i have have never ever stripped a single bolt head or broken a bolt,. or ever had an easy out break off,
I.ve never had an engine blow up on me either,.
In fact when i,m working on a project it all comes apart and goes back together just like the fsm tells it,..so i don't really understand all the fuss other folks have,..rusty old cars are never a problem for me,..
The 200lb bottles for the torches mean nothing at all to me,.

One very useful tool is the impact driver. I don't mean a pneumatic impact wrench, I refer to the hammer-powered tool, as in the first image of this[You must be registered and logged in to see this link.]. Hitting it with the hammer does 3 things all at once: keeps it firmly engaged, provides a shock to help break things loose, and of course, the rotational force.

They usually come with a 3/8" or 1/2" square drive plus an adapter and a few basic screw driver bits. One of mine came with a set of extra-long screwdriver bits, which can be very handy sometimes. For Torx, etc. simply remove the adapter and install a square drive bit from your socket set.

Best used with good quality bits of course, as Phantom 309 suggests above. Similarly, best used with good quality fasteners, but if anything has a chance of removing a rounded out screw head, this is the tool.

buickwagon wrote:

One very useful tool is the impact driver. I don't mean a pneumatic impact wrench, I refer to the hammer-powered tool, as in the first image of this[You must be registered and logged in to see this link.]. Hitting it with the hammer does 3 things all at once: keeps it firmly engaged, provides a shock to help break things loose, and of course, the rotational force.

They usually come with a 3/8" or 1/2" square drive plus an adapter and a few basic screw driver bits. One of mine came with a set of extra-long screwdriver bits, which can be very handy sometimes. For Torx, etc. simply remove the adapter and install a square drive bit from your socket set.

Best used with good quality bits of course, as Phantom 309 suggests above. Similarly, best used with good quality fasteners, but if anything has a chance of removing a rounded out screw head, this is the tool.

I still have my snap on "hammer impact" that I bought about 40 years ago when I was wrenching on all those air cooled jap bikes.That was the first tool you grabbed whenever you did any engine work to prevent stripped
screw heads.Wonderful tool that everyone should have in their box and even the good ones are pretty cheap to buy!

Olds Weighty Eight wrote:

I'm not giving up just yet. Hell, I'm almost there at this point.

I do know the old hammer trick as I had to employ it Saturday to remove the Thunderbird brake caliper T40 bolts. The OCC, on the other hand, felt like the bolt broke loose and started to turn when it was in fact the bit failing. Fooled me. 

Yeah, cheap China ****...my bad on that. Up until now the only thing I had used the T45 for was my G-body calipers.

Make sure to use all grade 8 bolts for reassembly!