Help Diagnose my 3B -- Blowby! (1 Viewer)

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Feb 1, 2013
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I was sitting at a stoplight and noticed a bunch of smoke from around the right front. Pulled over and opened hood, the tiny pipe I call The Blowby Pipe is smoking like a chimney. Open oil fill cap and same deal, huge pulses and smoke coming out. The radiator was a little low, like 4oz, and doesn't have a bunch of white gunk in it as if it were contaminated with oil.

Oil level is same as always, about 1/2 up the dipstick. Suddenly feeling religious I stopped at an autoparts store and poured in 8oz of marvel mystery oil.

Drove home and made an appointment to see my semi-local land cruiser experts. Unfortunately he's booked until April and this is my main vehicle. Not sure I can handle not having one for all of march.

I'd like to pick into this a bit and see what it might be but I have no idea how to proceed.

I'm guessing either the engine has s*** the bed and I'll be selling this dude off, or it is a stuck valve? Is there any in-between? What are some other things I can hope for?

1) I'll drain the oil and check for metal bits.
2) Cut open the oil filter and see what I find
3) I don't have a pressure gauge but can maybe borrow one. Should I check cylinder pressure through the glow plug holes?
4) The valves are under the valve cover on top? Should I take that off and have a look?

I dunno what to do. Sort of bummed at the moment.

Thanks.
 
Should also mention the truck sat for a few months this winter. The issue seemed to occur right away after I started driving it again. I think maybe on the first drive.
 
Sounds like some rings are stuck. There aren't many ways to get compression gasses into the crankcase quickly. I'd be tempted to take it out fir a good long drive. How long has it been behaving like this?
 
Like 4 5 mile drives on two days. Then I drove it 30 miles on the freeway and no difference. Then 30 miles home with the mystery oil. No difference.

The puffing is worse than any videos I’ve seen of blowby. Weird that power isn’t crazy bad.
 
Rings can freeze due to carbon and rust or a combo of both. There are cylinder cleaners I've used to free them in the past but it's messy toxic buisness. Your local gm dealer should have Acdelco "cleans". It's designed specifically to disolve upper cylinder/piston Carbon. It only comes in a spray bottle and can't use a straw to direct it and is horribly neurotoxic. Great combo. Awsome design. It also happens to be the most amazing carbon cleaner I've ever used. I first drain the oil. Then I empty the can of cleaner into an container and pour an even amount of it into each of the glow plugs holes. This will let it soak onto each pistin/rings. I then wait 45min - 1 hour. Then I drain the cleaner that ran past into the oil pan and fill engine with oil. Absolutely not any longer or the rings will refreezes. Ask me how I know. You can repeat the process so it's not the end of the world. Then I rotate the engine (in the correct rotation) to clear out the fluid left in the cylinder. It will squirt out. Did I mentiion it's toxic? After a few revolutions I burp the starter to clear the rest. It's crazy messy. You know it's toxic right? Then I replace glow plugs and take the truck for 20 minutes of hard driving.
Horribly toxic and messy and very effective when I've Done it. Repeat until desired results are achieved.
 
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Yeah maybe give it a fresh oil change with more marvel mystery oil or Rislone engine treatment and run it some more....keeping an eye on everything. Run it up a few hills and get it good and warm
 
Ok. I like these answers. FWIW: It doesn't sound like its firing on 3 cylinders. Revs fine but wow lots of white/brown smoke out of the blowby tube.

Valves can't do this can they? I've not adjusted them... ever.

That ac delco stuff... I don't like toxic stuff. Too much exposure in the past and now it makes me sick so quickly. Forget Por15.

I have a suit but my local hardware stores are sold out of all the proper canister filters because of the virus. I can use my old canisters but not for this.

How about this "Chem Dip"? Hmm... the sds doesn't seem to recommend tooth brushing.


Ok. I'll get going on this then. Glad for your suggestions. I'll soak the cylinders in the middle of the oil change.

Given how much gas is escaping I'm thinking I'll trivially be able to discover the problem cylinder using compressed air.
 
drove the few miles to the Chevy dealer. Got something called top end cleaner. Guy at the desk said it’s what all the other dealership mechanics come to buy... Volvo, Audi, Porsche. Is toxic. I stayed well away but the slight whiffs I got it didn’t smell like creeping death of por15.

Anyway, poured a few oz into each cylinder. Turned engine 720. Once I turned too fast and sprayed out all over. Waited an hour, turned again.

Refilled with oil and a liter of atf.


short cruise and engine seems happier. I’ll take it on a long trip tomorrow.
 
Your valves do not communicate with your oil pan.
So any carbon dissolving no touch cleaner is pretty much going to be toxic. You could try a really light solvent to just loosen the ring which might help. The problem is the evacuation of the fluid from the cylinder. I'm pretty sure aeroisolized marvel mystery oil will kill your liver as will pretty much most any petroleum product. I just finished an engine rinse on my Powerstroke with a cleaner called "kreen" from Kano labs. Has a cool smell. Not like a lets sniff the sharpie and get a buz smell, more like a citrus fast orange kind of smell. Did an amazing job but I watched my oil pressure like a hawk. Engine flushes can clogg your oil pick up if they clean too quickly. Kreen is suppose to clean slowly over 1000km. An engine cleaner can slowly clean ringlands from the bottom up but will take a much longer time. Bennifits are many but mostly that you avoid exposure to hazerdous chemicals.
 
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I'm not sure but I think por15 has arcinocyinides. A really good fresh charcoal respirator should give you some protection but a forced air set up is safest. Never forget your eyes can absorb alot of chemicals, enough to allow for liver damage and of course your skin...
Por15 should never be sprayed. Only brushed or rolled. Guys have died spraying it.
 
I'm not sure but I think por15 has arcinocyinides. A really good fresh charcoal respirator should give you some protection but a forced air set up is safest. Never forget your eyes can absorb alot of chemicals, enough to allow for liver damage and of course your skin...
Por15 should never be sprayed. Only brushed or rolled. Guys have died spraying it.

This acdelco stuff smelled like a really poisonous version of gasoline. Because of the toxic warning above and the possibility of it being messy, I wore my paint suit, goggles and my respirator with its old cartridge. Best protection I have. I only got a slight wiff of it when I was done.

I think tomorrow I'll get some seafoam. More the merrier.

What causes this carbon build up? I usually use rotella but just this last change I used delvac 1300. I doubt the oil makes any difference.

Also, sitting in my driveway... the truck has a hood, why would the rings rust?
 
Seafoam is on par with naptha and xylene etc....light solvent. The gm upper cylinder/combustion chamber cleaner is an industrial carbon cleaner. I think most of it has been removed from shelves and is no longer for sale if you have what I think you have. I've used it too but prefer cleans over it. Carbon doesn't come from the oil. Carbon comes from combustion. It coats everything it touches and loves to fill crack and cavities. Your ring land is no exception. Ambient humidity can do wonders on metal parts exposed to extreme heat. High temps bake all the oil most metals hold it their surface imperfections. Even when wiped clean oil is still present. Ask a painter which it sounds like you are. Ever wonder why all exhaust components are so extremely prone to rust or why your BBQ rusts to death even though you cover it? This is what engine fog prevents. Rust frozen rings and cylinder wall rust, valve rust......
 
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Ok... I'd driven the car around for 20 minutes after the oil change on thursday. Took maybe 15 seconds of cranking to start, sputtered a bit but then drove fine. Blowby was maybe a bit better at the end of the drive but still not like it was.

Yesterday I needed to head into town. Cranked and glowed for a few minutes and engine just wouldn't start. Big cloud of smoke. I checked glowplugs were seated, oil level, obvious stuff, just couldn't see anything wrong.

In the evening I cranked a bunch more and engine finally caught. Maybe 2-3 minutes of cranking. Thank goodness for dual batteries.

Sputtered and finally caught. I could smell the acdelco stuff in the smoke, so it was probably still in the cylinders and didn't want to burn?

Drove with brave wife for 45 minutes on the freeway to an event. After 2 hours in the cold the truck started right up and truck drove fine.

On returning home I think the blowby is now significantly reduced. I'll keep working on this. Get some seafoam today, etc. I think its on the road to recovery.

I guess this occurred because of all the rain driving and then leaving it to sit for a few months? I've had a different bj60 sitting next to the house for months at a time and it has never done this.

WRT the acdelco stuff. I did some research and there used to be a product called x66p. Also called "Acdelco combusion cleaner". It was sold in canadia as "Cleens." It is no longer being made or sold. Internet people are hording it. The stuff I got is the new formulation that happens to not be so toxic. Some report that it doesn't work as well as the old stuff.
 
Ive owned and driven diesels for years, never needed fuel conditioners. With good filtration, good injectors and regular use they will clean themselves.

Fuel conditioners can not cure blow by, it is worn metal leaving a gap between the rings and bore.

I guess this occurred because of all the rain driving and then leaving it to sit for a few months?


Why would it? The fuel system is sealed, it is not weather dependent. You should be able to drive it under water and not miss a beat.
 
Ive owned and driven diesels for years, never needed fuel conditioners. With good filtration, good injectors and regular use they will clean themselves.

Fuel conditioners can not cure blow by, it is worn metal leaving a gap between the rings and bore.




Why would it? The fuel system is sealed, it is not weather dependent. You should be able to drive it under water and not miss a beat.

Not talking about fuel system. Used top end cleaner directly in cylinders to try and soften carbon in rings.

Added seafoam today to oil and an hour of driving.

How long until oil needs changing? Should i change the oil filter?
 
Three weeks, about 700 miles. Blowby smoke is still embarrassingly bad. Power seems fine.

Not burning any oil.

What is involved in fixing this? Is it something a regular dummy could reasonably do? Rebuild is incredibly expensive. Starting to think i need to either:
- find a different engine
- get a different truck

im not ok with all the smoke

Thoughts?
 
Three weeks, about 700 miles. Blowby smoke is still embarrassingly bad. Power seems fine.

Not burning any oil.

What is involved in fixing this? Is it something a regular dummy could reasonably do? Rebuild is incredibly expensive. Starting to think i need to either:
- find a different engine
- get a different truck

im not ok with all the smoke

Thoughts?

You just need to take it to the next level. Not a full rebuild yet...

First, download the factory service manual for the 3B. Read it and get to know the engine.

Second, check and set your valve clearances. It's easy on the rocker head engines (3B). The later 1HDT/1HZ/1PZ etc. have a shim over bucket that is way more difficult.

You could pull the injectors and get them tested for spray pattern and pop pressure. Get them rebuilt if necessary.

If you still have issues, do a compression test to try to identify which cylinder is bad. Buy a diesel compression tester with the right fitting, or get someone to test it for you.

If there is bad compression, pull the cylinder head and inspect everything. If there is a bad cylinder bore, you'll see it and can make a call as to what to do at that point.
 

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