I was checking compression to figure out why my #8 cylinder keeps fouling out and dieing. Pics are below of what I found. One plug (not #8) looked like the end was a booger made of carbon- I had to knock some off to make sure it still had the ground strap.

Most of the buildup was on one side of each plug. I recently ran Seafoam through, and finally got the carb dialed in.

Any ideas what would cause this kind of buildup? The stars by the cylinders are the ones I replaced with some Accel plugs I had laying around (I only had 6, and no time to go to Advance).

 

Im sure you know that buildup is ash deposits from burning oil. The only two ways oil can enter a cylinder is through the rings or through the valve stem seals. Generally, only a small amount gets through the stem seals. The heavy buildup you have would tend to indicate poor ring seal. You might try Rislone or Marvels Mystery Oil to see if you can clean up the rings and get them working again. If not, it may be overhaul time. Of course youll send the heads out for service as part of your overhaul.

 

Timeline is needed

You say #8 keeps fouling. Does this mean that you keep changing plugs and they always look like this after xx miles? Or, since you said that you ran Sea Foam through the car, did you swap out the plugs after a week or two? If your car was really carbon fouled the sea foam will cause your plugs to need to be swapped after the cleaning.

So, if all of this is simply post-sea foam, then change your plugs. If this is a constant happening, then it's rebuild time

 

ASE Doc- I guess I was hoping it was from running too rich in conjuction with seafoam in the gas. Would you suggest pulling the plugs and squirting either of the 2 products you suggested and/or some GM Upper Engine Cleaner into the cylinders for a couple hours, and 'cranking' it all out? Maybe add some to the oil, run it for a couple hundred, drain and pray ? I just find it hard to believe that all the oil rings took a dump that fast after a complete rebuild, or that the guides and seals are bad already after the heads being completely gone through (only thing stock from the heads is the heads themselves).

torque_is_good- It has done this constantly for the last couple years. The car is only driven 3-4 months a year (started and brought up to temp every 1-2 weeks regardless of time of year), and maybe once or twice a week anywhere from 5 to 150 miles. I've been driving it more lately- did the seafoam (added to gas, oil, and through the brake vac line) about 3 weeks back. Engine only has about 4k on a complete rebuild. I seafoamed it (gas, oil, and injestion through a vac line) about 2 weeks ago. I'd imagine they were fouled before the seafoam- it had been a while since they'd been changed.

 

Sorry bro. That is oil ash. Fuel fouling doesnt leave those "flags" on the ground electrode. Only oil does that. If this is a recent rebuild, Im going to speculate that the rings never seated properly. Rislone or Marvel's may help that, along with a ring seating exercise. You add 1 quart of either product with an oil change, run it 3,000mi then repeat.

The trouble is, your recently rebuilt motor shouldn't have alot of build up. The Seafoam should have cleaned the upper cylinders. How is your PCV system? You need to have something in place to relieve crankcase pressure or youll get oil past the rings. Also, they do look rich. Hows your ignition KV? You may want to check it. Might need to address a weak ignition(coil, dist). High output motors need higher spark energy to fire the denser mixtures and fire consistantly in the higher cylinder pressures they develop. MSD is popular with racers because the multiple spark discharge helps provide more complete combustion in these high stress situations.

Ring seating goes like this: Find a long, steep hill where you can drive slowly. Climb the hill in second gear, keeping RPM around 1,500 - 2,000. Turn around and decend the hill the same way letting the engine hold vehicle speed. If second gear doesn't hold it well enough, use first gear. The idea here is to push and pull the engine. Press and pull on the rings to get them working. Repeat this process several times. Do this only after adding the oil additive. Be sure that you perform this process using dinosaur oil, not synthetic. If the problem is not solved by the steps explained here, you will need to re-ring the motor with a fresh crosshatch and start over.

Just so you know, I do this with every new motor I build. Its the only way to assure ring break in. I run 30 weight oil in my new motors for the first 1000mi, then I switch them to 15-50 Mobil1. Once they go on synthetic, the ring break in stops. The synthetic oil doesnt allow the friction needed to seat rings. Therefore this break in process has to be performed properly. Otherwise the engine will always use oil and the plugs will look like yours do. Its especially bad when I use low tension rings(1/16"). They tend to blow by anyway.

Your solution lies somewhere between ring seal, crankcase ventilation, and ignition system. Take a close look at each. I hate to even say this but are you sure you installed the rings correctly? Did you align the compression ring gaps with the wrist pin, the oil ring gaps at 90degrees, centered on the wrist pin? Did you get them in right side up?

 

Looks like I might have multiple causes.......part of the problem is in my oil then....I switched over to Mobil 1 Syn after about 500 miles IIRC. Started with Rotella oil, then dino M1. I also added GM EOS at each change for the zinc additive that's not in the oils anymore.

I did replace the PCV valve last night as well- just to eliminate it. The other valve cover has just a plain breather.

I know just the hill to try that on- same one I used with my original break in run, but a bit different procedure.

Ignition is a 70's distributor with the following: Accel Cap, rotor (fresh one waiting to go in), Accel Supercoil, Accel ICU, curve kit w/ 1 light and 1 medium spring, Accel Vac can, and Taylor thundervolt wires.

In regards to the rings, I do recall the 90* spacing. I honestly don't recall in regards to right side up or not........I did follow the directions in the manual to a T, and triple checked all clearances and orientations.

Since they haven't even set, should I try and 'flush' them out anyway by using some MMO/Top end cleaner in each cylnder to make sure there's no buildup preventing them from setting using the above procedure? I'm worried not only about getting them to seat, but also breaking a ring should there be any buildup in the grooves.

THANKS for all your help!!!

 

The problem I see with pouring anything in the cylinders is the obvious danger to rings and head gaskets should you turn the motor over with anything but air and fuel vapor in the combustion chambers. Even a little liquid can over-pressure a head gasket. In my experiencxe, I have not seen a ring break due to being stuck in its groove. Ive only seen them not work.

The method I suggest for using MMO or Rislone is not a quick fix. The process takes time. If youre concerned that you may have a heavy varnish buildup in the ring grooves, you may want to run the additive for some time before you perform the ring break in. Dont be afraid to run some Seafoam through it at each oil change until this problem is cleared up. The oil additive will loosen up the rings from below but it wont prevent the buildup in the chambers as long as oil is still getting through.

Im quite sure now of what happened to you. You went synthetic too soon. You added zinc to your oil. Do you run a flat tappet cam? I dont believe the zinc to be that big a deal with roller cams. Flat tappet lobe failure is the major concern with reduced zinc content.

 

My plan was to squirt it into each one, let it soak overnight, and while the plugs were out, turn it over several times to push any fluid left in the cylinder out. I understand what you are saying about the dangers of anything other than fuel vapor in the cylinder- recipe for disaster if the plugs are in.

I added the zinc due to my flat tappet cam. Ounce of prevention (16 ounces I guess).

I'll do the seafoam/oil treatment for a while, and after I get a few thousand more on it, try to set them again. My only problem is how sporadic I actually drive the car (especially over the next 5 months). Rain and snow are not my friends.

 

Lol. Yeah I get the no driving in cra**y weather. Its starting to rain here which means its time to store the IROC for the winter. Its sounds like youre on the right track.

 

So here's an update.

2 weekends ago I pulled the plugs, and squirted a can of seafoam into each cylinder and let it sit for about 30-36 hours, after which I turned the engine over for about 20-30 seconds to pump all the fluid out of the cylinders.

I then changed the oil (dino mixed with a can of BG MOA and a half can of seafoam added to the oil), I also bought some new Delcos (45TS) and installed them. I also swapped the PCV valve for one that I had in the garage. I took her on about a 25 mile drive after I smoked everything out, did some vacum pulls just to see what she'd do, and it smoked on decel a bit. Pulled the plugs after she cooled down, and they looked fine- just like they should.

Drove her to work one day last week (about 125 miles total), and pulled the plugs. They were already starting to oil foul, although one looked pretty good. Lost about 1 qt of oil.

Pulled them and cleaned the ash and oil off, and repeated the cylinder soaking procedure but with a 50/50 mix of B12 chemtool and seafoam. Soaked for 30+hours. Reinstalled the cleaned plugs, smoked her out, drove her and got some smoke on decel but more lower rpms.

I was researching PCV valves and thinking maybe that was a cause, or an intake manifold leak. I started the car and warmed her up. Had plenty of vacuum through the PCV. Removed it and plugged the nipple on the carb, and didn't really feel any vacuum or pressure over the hole. I did have the lid to the air cleaner off, though, and could see smoke coming from the breather tube that feeds into the air cleaner (L69 Dual Snorkel). So, I am getting a decent amount of pressure. I'm going to try and run it with a plain jane open element breather in place of the PCV, and see what happens with the plugs and oil level.

My brother in law (not the good for nothing type) also recommended that I run some BG quick clean through it since they use that at their shop with fantastic results, and the stealerships here in town don't have the GM Top Engine Cleaner. I plan on doing that at the next oil change and maybe even trying some Rotella since it's already got ZDDP in it (save $10-20 an oil change- no more MOA or EOS!), and it has more detergents for cleaning and suspending soot.

Sorry for the long post, but with the above info, wouldn't you think the rings are ok since even after 30+ hours each time a LOT of the liquid I squirted into the cylinders squirted out onto the headers and frame rails?

I do plan on pulling my valve covers when I get a chance to check the oil return holes and check the seals. I thought maybe that could be another cause since I eliminated the intake, and will be eliminating the PCV after my next trip to the office- hopefully tomorrow.

 

Rings are probably fine.

More likely, it needs valve guide seals. VERY common, almost inevitable even, on SBCs of all ages and sizes.

Nothing you pour in the crankcase is going to make any difference to that.

 

I knew it was a common problem- I just have always though when they went bad you had the puff of blue smoke at startup. With the heads being fresh (rebuilt with new valves/guides/seals) at the same time as the shortblock, I would think they'd (seals) last a bit longer.

I picked up some new valve seals (Felpro SS72527). I plan on doing both intake and exhaust with that seal. I'll hopefully have time in the next couple weeks to try it out.

Drove the car to the office- seemed to smoke a little less at a little lower rpm without the PCV in case anyone is wanting to know- but I wasn't doing hard (1500-2000, or 1500-4000 1st and 2nd gear) back to back to back vacuum pulls like I had before, either.

The exhaust fumes overpower my cologne

 

Do you have access to a flexible borescope? If so, pull off the carb or TB and snake that thing down the intake so you can see the backside of the intake valves. If it's got carbon built up on it 1/8"+ thick then most of the oil is coming past the valve seals (possibly made worse if the valve guides themselves are badly worn). If the backs of the intake valves are fairly clean then the oil is coming past the rings.

If you see the BG44K ad at the bottom of this thread, take a look at the "dirty" side of the valve in the picture. That's MILD oil caking compared to what can happen if the guides/seals are badly shot.

Also, plugs that have deposits mostly on one side of the plug indicates the oil is coming in through the intake valve (the dirty side will point directly at the intake valve for the cylinder it was installed in). Oil coating the plug threads is also more of an indication of oil coming in the intake, less an indication of it coming past the rings.

Your comment about not knowing if you had the rings installed in the proper orientation (up vs. down) is troubling. Get it wrong and it'll burn plenty of oil. The 2nd compression ring acts at least 50% as an oil scraper. Get the top ring wrong and it won't seal in combustion compression worth a lick (lots of blow-by that your PCV valve can be picking up).

 

I don't have a borescope- I'll have to see if my bro in law does that I could borrow. Otherwise, I did see one on ebay that was pretty inexpensive and could connect to my laptop.....another tool! That'll make the wifey smile

I can't see any of the ads due to my ad blocking program, but I know what you're talking about.

When you say oil on the plug threads is more intake- as in intake valve, or intake manifold? I have had a pretty decent amount of oil on the threads. Also, the plug fouling from oil has been the last year or so (maybe 1500-2k miles). Engine was assembled in July of 2007

I know that my statement earlier in the thread can be un-nerving- but I honestly don't remember the 'destructions'. Like I said earlier, if the piston 'destructions' said to do it with the dot up and clocked at 9, and the 2nd ring clocked at 12, that's what I did. I also double checked what the manual said, but ultimately went with the piston ring instructions. I triple checked everything since I didn't want to tear it apart again until it was time to slide a 350 shortblock under it all.

 

Although I doubt it's your problem due to the fact that it's occuring in more than one or two cylinders, oil does have a third possible entry point: internal vacuum leak through the intake manifold gasket(s). When that happens it pulls oil from the lifter valley into the respective intake port(s) and gives the exact syptoms you are experiencing.

 

Following up with this. Just pulled the engine 2 weeks ago- replaced the oil pump with a M155 and Canton bolton pickup, New Canton oil pan, Fel Pro offset rear main (knock on wood no more leaks this time YAY!!!), and now I'm doing the valve seals. Using the blue Fel Pro positive seals that I talked about a few posts up.

My question now- is there some trick to locking them onto the head- some crimp tool, etc? I used a hose clamp to try and clamp it down and get the metal collars tight, which makes them hold the boss better, but without doing that, they pull up with a decent amount of force.

Or am I over analyzing and just push them on (using the provided valve sleeve/protector of course) and just leave them?

 

so you're finally taking the steps to address the problem and you aren't bringing the heads to a shop for new guides and seats???????????

yes, a valve job might be as high as $300 for both heads but isn't it worth it since you have them off?

 

The heads are NOT off- I just pulled the engine to make life easier doing the oil pan, pump and RMS.

Also, valves and guides are fresh from machine shop in '07, and have just a few thousand on them.

 

if the engine is out, it's just some head gaskets and an intake gasket. I'd yank the heads so I could inspect them and at least lap the valves.

while it's out a new rear main seal would definitely be on my list as well, even if it was replaced 4 years ago.

 

Already finished up on the bottom end. Just doing this while it's out and I don't have to stoop over the car and shell out my knee and lower back (lowered Camaro's aren't the greatest for the back!).

Don't take this the wrong way, but I honestly have no desire (or time and budget for gaskets, head bolts, machine work) to lap the valves or tear it down that far- I have a 350 that I've been allocating for, so the next time the 305 is out that will go in. Then I'll budget for going through the heads again if I re-use them. Just doing some cheap fixes.

I also find it hard to believe that in less than 4 years and 3-4k, the new guides and new Manley Race Flo valves are shot. Umbrella seals, though, the 1st one looked chewed up.

 

where there's smoke there's fire. 4k miles and you see seal issues. What makes you think the rest of the head work was done correctly?

There is a lot of shoddy work done out there.

 

I put an engine together.
GREAT care in making it ALL blue print, and CLEAN.
Had a "friend" drop it in for me.
Three miles later, ( count 'em THREE ) got smoke, oil out the dipstick, and other nasties.
Found 1/2 teaspoon of loose rust in the oil pan.
Total tear-down time.
Infant mortality should tell you something.
I'd pull the heads while it's out, and look.

 

My 84 T/A is also doing the same with the plug. Other than changing the plugs upon feeling a loss of power due to plug fouling up is there any way to temporarily address the issue?

 

Ended up being the intake gasket. The center bolts lost torque, but I replaced the gaskets as well as the valve seals too.