$400 Find, Seized while using the starter? (see pg 3) - Page 4 - PeachParts Mercedes-Benz Forum

bgkast · #46 07-24-2006, 07:55 PM

I have eliminated the belt driven accessories and valve train. I'll pull the starter a bit later. Anybody else have any ideas, or think that I could have fatally seized it while cranking it? Is it possible for the IP to jam and seize the engine? Thank you. –Bryan

#47 07-24-2006, 08:03 PM

I have had this happen before, the starter is binding on the flywheel. The bendix is still thrown out and binding on the flywheel teeth. Sometimes, with a weak battery, the bendix won't come back after you release the key. I just had to remove and relace the starter on my Ford 8N tractor after I ran the weak battery down trying to start it. The engine was frozen solid. I hope this helps.

Endust · #48 07-24-2006, 08:29 PM

Yeppers. Thats why pull starter was #1 on my list. I had that happen in my diesel blazer on a cold morning. I wacked the starter with a 5 pound hammer and I heard it snap back. Starter died soon after....one of many in that infernal beast.

Stevo · #49 07-24-2006, 08:57 PM

John Holmes III you just beat me to it. I had the opposite thing just happen, ring gear spinning round the f/w, I becha you pigged it

bgkast · #50 07-24-2006, 10:24 PM

It's not the starter. I pulled it and it was still stuck. I found a post where somebody described their cam chain tensioner failing and allowing the chain to wrap around the lower sprocket and then hit the oil pan. I think I will try pulling the pan next. Stay tuned.

Stevo · #51 07-24-2006, 10:35 PM

[QUOTE=bgkast]It's not the starter. Too bad

this is turning into quite the mystery, pulling the lower pan seems like the next place to go. You might try turning the eng by prying on the ring gear. Which you proly already did

#52 07-24-2006, 10:58 PM

That's a shame. It is a nice looking car, and worth saving. IMHO.

bgkast · #53 07-25-2006, 01:47 AM

Well I have tried everything I can think of. It is not the valve train, starter, Cam chain, injection pump or belt driven accessories that are holding it up. The transmission is in neutral and I can push the car, but I can not depress the clutch because I have removed the hydraulic line for replacement. I still can’t believe that it seized while cranking with the starter, but I guess that is the only explanation.

Can anybody think of any thing else to try?

The car will be saved even though the engine is dead. It will just have to wait a few months until I have more time, then I will put a junkyard engine in it. The body is too good to scrap it. I really like the color. It is 922 Pastel Blue. I have never seen a car with this color before. Anybody know where I could find production #s by paint color?

nhdoc · #54 07-25-2006, 07:53 AM

Are you 100% SURE it is in neutral? Maybe the shift linkage also has bubba springs on it? I would check there too before condemning the engine. If it's in any gear you would not be able to turn it by hand if it is a 4 speed. Just a thought.

#55 07-25-2006, 07:54 AM

I wonder, if the pressure plate and throwout bearing are jammed up somehow. It's just so bizarre that this happened at cranking speed.

franklyspeaking · #56 07-25-2006, 12:04 PM

I am a living testimony that, if the chain tensioner fails, there is enough slack in the chain to wrap around the bottom sprocket and lock the engine. I did this twice and the second time the chain broke - both during starting. It may be possible to take a breaker bar and turn the engine backwards slightly to free up the chain, if it is not broken. Then of course, the root cause of the problem (tensioner system) must be repaired. Since there is insufficient room between the upper oil pan and the sprocket with 3 thicknesses of chain, there is iterference with the chain and the oil pan - in mine it made a hole that had to be patched. After the chain broke, I pulled the engine, removed the pan and had it welded up (aluminum). My experience was the only one I have ever heard of, but this one sure sounds similar.

Bgkast, I wrote you an email with same details above....goodluck!

jrgslg · #57 07-25-2006, 12:29 PM

Okay heres a thought,on a sprintcar to clear out the cylinders of fuel,you put it in gear and rock it backwards,this makes the engine push everything out the exhaust (could it be a fluid lock?) ,it may be a stretch but that seems where you are,I would put it in your highest gear and try to rock the car backwards,Johnny

After reread you would have to make the valves open to remove any fluid if it was trapped and indeed the culprit,this is indeed a puzzle.

bgkast · #58 07-25-2006, 03:39 PM

I am positive it is in neutral, as I was pushing the car. I tired putting it in hear and rocking it but it just torques the engine on its mounts. It is not a fluid lock because I have pulled all of the injectors and glow plugs. I guess I will check the clutch for normal operation when I get the new hydraulic hose in a day or two. The cam chain looks to be properly tensioned and I looked at the lower sprocket by removing the oil pan. It looked fine. I did notice that despite all of the cranking the cam looked a bit dry, but I still find it hard to believe that cranking, even with no oil pressure could seize it. I think I will try a breaker bar on the crankshaft nut and rock it back and forth to see if I can get it to budge.

Endust · #59 07-25-2006, 03:44 PM

Seizing an engine requires heat. At starter speeds there isnt anywhere near enough heat. How did you eliminate the valve train? Since the starter wasnt the cause I think you have valve interference. What process did you use to eliminate that as a possibility?

jrgslg · #60 07-25-2006, 03:58 PM

Okay ,looks like your gonna have to tear down the motor just to let us know what the heck happened.Sorry I wasnt able to be of more help,keep us posted,good luck.Johnny