installing new injector, noticed ball in prechamber is broken off!!! - PeachParts Mercedes-Benz Forum

Ted Daniels · #1 03-24-2008, 11:04 PM

I had thrown marvel mystery oil in the combustion chambers, just to soak some you know. maybe get a ring unstuck here and there... so anyway, before installing (elsbett) injectors I of course turned the engine some holding the key for 8 seconds or so. I don't need aqua lock in a 617..
and what do I notice? the ball in prechamber #3 actually wanted to get out through the hole!! when I tried to grab it with a magnet it appeared to be too big and fell back in. wow. anyone ever seen this?

Brian Carlton · #2 03-24-2008, 11:24 PM

The "ball" in the prechamber is actually a shaft with a large center section. This shaft is pressed into the prechamber side walls. After 200K, the shaft loosens in the side walls and is definitely in danger of falling out of the side wall and down into the bottom of the prechamber.

Replacing the prechambers is certainly a serious consideration at 200K.........to prevent such a catastropic occurrence. I had them all replaced when the head was done on the SD..........cost was about $60 per.

Ted Daniels · #3 03-25-2008, 12:04 AM

kinda sucks.
I already replaced oil cooler lines, turbo drain seals, airfilter 'blowby' seals, air filter mounts, intake manifold gasket, turbo inlet and outlet gaskets, oil filter housing gasket, oil pan gasket, oil pump screen, motor mounts, ball joints, tie rods, center drag link, transmission cooler lines, injectors, heat shields, return lines, valve cover gasket, vacuum pump gasket, front crank seal, transmission rear seal, transmission pan gasket, transmission filter, power steering return hose, power steering filter, power steering fluid, all rotors and pads, brake fluid, stabilizer bars rear, upper ball joints/arms, both flex discs, center drive shaft bearing (still working on rebooting the axles) receiver drier, pressure switch, waterpump, coolant, overflow cannister...
when does this stop?
what's that BS about 'running forever'??
yeah, any freakin' car will run forever after replacing pretty much everything.

my god. my honda is so much better.
sorry about the rant.

pawoSD · #4 03-25-2008, 12:21 AM

It seems that prechamber ball failure is random....my dad's were all intact at 280k or so when we pulled his injectors....and mine were all fine when I pulled mine around 257k....

At least pre-chambers aren't super expensive....they're not cheap, but not super high.

pawoSD · #5 03-25-2008, 12:23 AM

Quote:

Originally Posted by Ted Daniels

my honda is so much better.

Not in an accident its not....

That alone is enough encouragement for me to drive a MB/swallow some of the associated expenses. I never want to be T-boned in a car and be sitting in a haze with a piece of steel in my abdomen. No thanks....

habraken · #6 03-25-2008, 12:30 AM

Quote:

Originally Posted by pawoSD

Not in an accident its not....

That alone is enough encouragement for me to drive a MB/swallow some of the associated expenses. I never want to be T-boned in a car and be sitting in a haze with a piece of steel in my abdomen. No thanks....

you go when you go. choice of car will not change your path.

habraken · #7 03-25-2008, 12:34 AM

no offence but Honda makes a way better car. the Nazi's were smart but them sneaky japanese were waaaay smarter. let's face it.
they are prettier too. their cars and their girls.

Ted Daniels · #8 03-25-2008, 12:40 AM

Quote:

Originally Posted by pawoSD

Not in an accident its not....

That alone is enough encouragement for me to drive a MB/swallow some of the associated expenses. I never want to be T-boned in a car and be sitting in a haze with a piece of steel in my abdomen. No thanks....

I heard that honda is pretty good about being flexible/ bendable where it needs to be? as in, being weak is sometimes better than being rigid?
all I know is that I'd rather crash in a mercedes or a japanese car. I have a friend working at the first aid dep. at the hospital. he says you crash in a us made car, you die...

turbobenz · #9 03-25-2008, 12:48 AM

Bull****. No honda is going to give its life for yours. Habraken, you say you go when you go? Well that may be, but if I was in an honda instead of a Mercedes when I got t-bone, I may not be the same as I am today, or even alive. Sure, maybe if i drove a honda that crash would have never of happened just becuase id be in a different place at a different time, but why take the chances? At least in a benz I know im safe if i do crash, whereas in an econobox I can count on going to the emergency room.

bgkast · #10 03-25-2008, 12:27 AM

I'll take that SD off of your hands.

Ted Daniels · #11 03-25-2008, 12:36 AM

Quote:

Originally Posted by bgkast

I'll take that SD off of your hands.

$7500. a bargain, really.

Diesel911 · #12 03-25-2008, 12:56 AM

Back to the ball in the chamber: If your injector spray patteren was not going where it is supposed to the fuel will burn there and can eventually start to burn through metal.
Some where there is a thread that tells you how to make a tool to pull the Pre-combustion chamber out (you attatch the slide wrench to it). Ebay is selling the correct tool but I have already been out bid on it.

C Sean Watts · #13 03-25-2008, 08:27 AM

own a Honda OR a Smart.

http://www.youtube.com/watch?v=m_86RuYXoJA

The physics of F=MA does not care what company's name is on the car, or how many crumple zones it has.

BTW, the PC(s) should be replaced.

winmutt · #14 03-25-2008, 10:12 AM

To get back to the thread at hand. I have the necessary tools to remove the prechamber ring, You can make a puller with a 22mm?x1 bicycle crank wrench. Prechambers and injectors should be inspected every 100k. New PC are pretty expensive, I pulled some used ones from pullapart. The ball issue is not that uncommon. I have had 3 balls, gp tips AND PC bottoms go out through the exhaust and the car still runs (smokes when cold). Try that with any japanese car and see what happens.

riethoven · #15 04-01-2008, 07:49 PM

Quote:

Originally Posted by winmutt

To get back to the thread at hand. I have the necessary tools to remove the prechamber ring, You can make a puller with a 22mm?x1 bicycle crank wrench. Prechambers and injectors should be inspected every 100k. New PC are pretty expensive, I pulled some used ones from pullapart. The ball issue is not that uncommon. I have had 3 balls, gp tips AND PC bottoms go out through the exhaust and the car still runs (smokes when cold). Try that with any japanese car and see what happens.

This may shed some light on what is going on with my wife's car. It is a 1987 300TDt and was running pretty good except it lacked power. It has always cranked well in the cold, even down to 18 degrees. I checked the pump timing with the pump lock tool and it was at 11 ATDC and I adjusted it to about 14.5 and it made no difference. It had also started smoking really bad at cold start and was even more anemic than usual. I checked the resistance on the glow plugs and they were all under 30 OHMS (The FSM says as long as they don;t read infinity they are good) except number three that was at 3200 OHMS. I had a spare and thought I could pull out the bad one and have a new installed in 15 minutes. The lead came off easy enough and I unscrewed the glow plug but could not pull it out. It is tight quarters with the intake plenum still on but I was able to get a pair of pliers in there but still could not pull it out. After playing for a while, trying not to pull of the intake plenum, I ended up pulling the plenum and prying the glow plug out. Here is a photo of the culprit.

The injector lines were also a mess so I pulled them off and pulled the number three injector and prechamber and noticed that the ball was missing. I had a spare prechamber and another injector (untested) and put it in with high hopes that if would stop the smoking at cold start. It did not. I had already done two liters of dieselpurge and that did not seem to help either. I have been super busy lately with other things, but know that before it is all over I will have to pull the intake again as well as all the injectors and prechambers and check them as well as doing a compression test. I am waiting for the compression tester to get here and I am shopping for a pop tester now. It will cost a few dollars in tools and some hours of labor but it will be done right and cost much less than any shop would charge me.

BTW, I was able to vacuum out the combustion chamber very well with my shop vac. When I was cleaning things up after I pulled the prechamber, some junk fell into the combustion chamber and I was could see it in there. I got the shop vac and sucked it right out.