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

[RufusTheDufus]

I never really understood the Seafoam in the oil thing for any engines other than small Briggs & Stratton style grass cutter engines. Seafoam evaporates so quickly I would expect it to be gone shortly after the engine is up to temp. I know people use it in the crankcase for sticky hydraulic lifters and that makes sense to me. But I doubt it can do much for carbon in the ring packs.

I've used Seafoam the same the GM top end cleaner is used. Just pull out the glow plugs and pour some in and let it sit for 10 to 15 mins. Crank the engine to blow the mess out of the glow plug hole and repeat. (Put some rags over the glow plug holes to catch the liquid mess that's going to shoot out.) If you're trying to un-stick a ring it will likely take more than one attempt. If the solvent/Seafoam has a small path to leak past the rings down the cylinder walls only a portion of it will be available to clean the stuck area of the ring pack. Might be best to rotate the engine so the pistons are close to TDC and just fill them up and let them sit.

I was eventually able to unstick the rings on this piston after a few cleaning attempts. The engine ran surprisingly well but had terrible blowby issues.

 

[zakthor]

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.

I have the manual. Have looked at what i need to do. what i dont know if its reasonable for me to tackle. Especially given cost of a different engine.

my understanding is that valves are irrelevant to blowby. Fix for rings means removing the head at which point its money for parts and machining to make engine an engine again. How hard is of to sell a truck that wont go?

i remember reading that most heads are cracked and not simple to bolt them back on.

Agree i gotta measure compression but i dont like the price for a reasonable quality tool that ill only use once.

is there any possible cheap fix for me other than the chemical path ive already taken?

 

[zakthor]

I never really understood the Seafoam in the oil thing for any engines other than small Briggs & Stratton style grass cutter engines. Seafoam evaporates so quickly I would expect it to be gone shortly after the engine is up to temp. I know people use it in the crankcase for sticky hydraulic lifters and that makes sense to me. But I doubt it can do much for carbon in the ring packs.

I've used Seafoam the same the GM top end cleaner is used. Just pull out the glow plugs and pour some in and let it sit for 10 to 15 mins. Crank the engine to blow the mess out of the glow plug hole and repeat. (Put some rags over the glow plug holes to catch the liquid mess that's going to shoot out.) If you're trying to un-stick a ring it will likely take more than one attempt. If the solvent/Seafoam has a small path to leak past the rings down the cylinder walls only a portion of it will be available to clean the stuck area of the ring pack. Might be best to rotate the engine so the pistons are close to TDC and just fill them up and let them sit.

I was eventually able to unstick the rings on this piston after a few cleaning attempts. The engine ran surprisingly well but had terrible blowby issues.

View attachment 2253244

cool! that is encouraging ill try a few more times with the top end cleaner.

 

[DEADSALT]

brown smoke out of the blowby pipe?

rings/valves don't deteriote in a 3b from sitting for a few months.

whats coming out of the rear tailpipe, check it.

is there good flow....?,
what colour is it,
what does it smell like?
how old is your exhaust, collapsed baffle restriction?
where do you live, is your muffler a new tiny home for rodents?


hopefully you kept your early April appointment with the shop and all is well,
interested to see how this turned out

 

[zakthor]

brown smoke out of the blowby pipe?

rings/valves don't deteriote in a 3b from sitting for a few months.

whats coming out of the rear tailpipe, check it.

is there good flow....?,
what colour is it,
what does it smell like?
how old is your exhaust, collapsed baffle restriction?
where do you live, is your muffler a new tiny home for rodents?


hopefully you kept your early April appointment with the shop and all is well,
interested to see how this turned out

Exhaust flow seemed fine. No muffler, its a turbo'd 3b. No rodent sign that I can spot.

I ordered a used motor from... a bad seller... that is across the country. Ordered in november the motor arrived at mechanic 2 weeks ago, a day after my mechanic appointment. The ordered motor had scars in sleeves, mechanic said no good, send it back. So I'm out for shipping and reinstalling the head but at least can return it. Live and learn. Picked truck up from mechanic and motor blew chow in less than a mile. Horrible knocking followed by loss of power followed by brown smoke that reeked of coolant. Barely made it to side of freeway. Radiator fluid now white with coolant and oil had exploded over the engine from under the head on both sides.

Uhh... (breathing into paper sack)... these trucks have been good to me but unless I find a decent motor I think I'm done. I put a wanted ad in the classifieds. I like the truck, its fine, but now no motor. Any other motor that can be reasonably swapped in place of a 3b?

Video of truck and blowby just before I drove it up to mechanic:



Tears.

 

[DEADSALT]

it’s been a couple of days, rare as it is, losing a 3B is never easy.

how many km’s, which turbo were you running (boost and egt max/min)


.....and I still can’t understand ‘brown’ smoke (Toyota red and some weird synthetic oil?)


what was the compression in the engine you sent back and what’s a used 3B going for in the states?

Your best option is finding a decent 3B and keep on trucking.
Still lots of rusted out BJ60’s with good hearts in Canuckastan,
post where you’re located, yah never know.

 

[DEADSALT]

and don’t toss your old 3B in the bin quite yet

 

[zakthor]

Hi Everyone. I finally get to close the loop on this. Wow checking the date it really did take an entire year from beginning to end. Would have been forever if not for the grace and competence of Torfab in Everett, WA.

I called them for advice and they recommended that I find a better engine but dollars were too large. This is my piece of junk truck right? Not worth anything. I'll just find another motor and put that in.

Well... the pages of the calendar have been swept away and the time of cheap new 3b are in the past. I found a "great condiiton" motor at cruiserparts and they promised to hustle it to me. Due to covid and a variety of excuses it took 4 months for motor to arrive. Torfab said it looked like a piece of junk, they popped the head and found scarring on all cylinders. I paid to have it buttoned back up and mailed back.

Thankfully 40justin on here had a 3b to sell me. It arrived in less than a week with super reasonable shipping price. Torfab popped the head and said motor was great inside but head was cracked, fortunately the head on my old motor was in good shape.

The neat thing is... when they removed my head they found the root cause of the blowby. One of the cylinders had a hole innit! So: not carbon rings, warn't nothing fixable.

Picked up truck today. Torfab had spruced it up with these fancy hose clamps, new glow solenoid, sparkly zinc plated nuts, just awesome. And sounds like a damn sewing machine. Motor has never sounded so good.

The best thing of all. I took 3 years break from work and started a new job a bit over a month ago. Is a very stressful and difficult job. So I go pick up the truck, its a hot day, windows down, driving home on 405, got the phone playing Thomas Pynchon's Gravity's Rainbow book on tape on my $100 Excelon headunit and great sounding jl audio speakers, everything is so familiar and so right. I really really missed this truck. Had no idea how much I missed it and now its back. Got my mtb rack on it so back to easy trips to the trails. Huge relief to get this piece of my life back.

I'm super thankful to Torfab. They warned me about the 3b, said it was tough to repair these days, down on power, not a good choice, big labor and not much reason. But when they agreed to do the work they stood by their word and did a terrific job. I'm grateful for their patience dealing with some dingbat buying random motors from all over the country.

 

[zakthor]

Here is the source of the blowby. It is only a small hole... The cylinder walls have no scarring...

 

[roalco]

All i can see is a hole in one of the piston crowns, very fixable, just replace the piston!