Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help




Go Back   PeachParts Mercedes ShopForum > Technical Information and Support > Tech Help

Reply
 
LinkBack Thread Tools Display Modes
  #1  
Old 09-07-2001, 08:55 AM
mplafleur's Avatar
User Friendly
 
Join Date: Sep 2001
Location: Lathrup Village, Michigan
Posts: 2,939
Unhappy 190E 2.6L Timing chain broke

The timing chain on my '89 190E 2.6L. Is this engine free wheeling? Do I need to look for piston/valve damage?

I was ging about 75 mph when it broke. I don't hear anything hitting when I crank the engine and I also removed the spark plugs and didn't see any damage in any of the bores that I could actually see anything in. There seems to be clearance in one of the cylinders that I think is at the top and a valve is opened, but I'm not sure that it is fully opened or at the very top of travel.
Reply With Quote
  #2  
Old 09-07-2001, 09:05 AM
LarryBible
Guest
 
Posts: n/a
You said you don't hear anything hitting while you crank the engine. Have you already replaced the chain? I would not expect cylinder damage, if anything there will be bent valves. The good news is that these engines come apart and go back together very well.

The thing to do is to check compression after replacing the chain. If the compression is okay, you'll be good to go. I don't know if these are interference engines, but I will be surprised if they are not.

How many miles on the car, and how often did you change oil?

Best of luck,
Reply With Quote
  #3  
Old 09-07-2001, 10:27 AM
mplafleur's Avatar
User Friendly
 
Join Date: Sep 2001
Location: Lathrup Village, Michigan
Posts: 2,939
I ordered the chain this morning. I have only removed the valve cover late last night. Everything else will come off tonight.

The car has logged 230,000 miles. I use synthetic oil and thus change the oil at about every 10k. The timing cover leaks (don't they all?) so I end up putting in a new quart every 6-700 miles.

I will be changing oil in much shorter intervals after this repair as I am going to switch to a heavier weight oil. My oil pressure goes down when the engine warms up which I attribute to a 'loose' engine. My oil leak should also go away.


It sounds like I shouldn't expect any valve or piston damage, so I can replace the chain and then check the compression.

Should I also replace the chain rails and tension rail?
Reply With Quote
  #4  
Old 09-07-2001, 01:49 PM
agupta
Guest
 
Posts: n/a
Was your chain noisy during the last stages? Specifically, did your chain rattle on cold starts, with the rattling going away when oil pressure built up?

I am just trying to see if there are any "symptoms" that all of us could look for, and save the damage due to a broken chain. Would appreciate anything that you can provide.

Hope your fix up comes out reasonable! BTW, do replace the chain tensioner along with the rails. Also, is your engine 16v or 8v?

Rags
(85 190E 2.3, 120 K)
Reply With Quote
  #5  
Old 09-07-2001, 02:22 PM
LarryBible
Guest
 
Posts: n/a
I'm sorry to disagree with Agupta, but there is really nothing to go wrong with the chain tensioner itself. You just need to remove it and push the plunger all the way through then reinsert it from the back side. It ratchets to take up the slack as the chain wears. By pushing it through, then reinserting it you allow slack that will be automatically taken up by the tensioner. If you don't do this you will probably break something.

Agupta's recommendation for replacing the rails could have some merit, however, unless there is one broken, which could be the cause of the problem in the first place, the tensioner will take up any slack that may be added by worn chain guides.

As for the upper timing cover leak, there is no reason for it to leak except if it were installed by someone who did not know how to put it on correctly. The main thing to know, which will get the upper cover on correctly, is using the correct sealant. MB sells a translucent blue sealer for this application. It is not a silicone, it is translucent and has an acrylic smell. This sealer will allow you to push the cover rearward into place without disturbing the U seal at the bottom. Use the translucent blue on the U seal and cover to head mating surface and gob it in the lower rear corners. Use your fingernail on the shaft seal that you have oiled to start the shaft seal without it "folding". If you use this procedure and this sealer, you can put it on every time with no leak as a result.

I'm sorry if I gave you the impression that you will have no bent valves. I really don't know if these are interference engines, and I'm sorry that your engine is going to be the one from which we learn this. Best of luck with that. If the valves ARE bent, it would be worth pulling the head and replacing valves as needed, and all valve guides. At this mileage, this engine would most likely respond very well to a fresh head. The cylinder head on these engines come off and go back on quite well. How well these engines run is all in the cylinder head. You will most likely find very little cylinder wear after removing the head. I'm just throwing in these comments, I'm sure your hope is a fresh chain and back on the road again.

How low does your oil pressure go when hot? MB says that as low as .7 BAR is okay hot. That is about 10PSI. If the oil pressure is not falling below that, I would not recommend heavier oil. The synthetic in a reasonable weight should be fine. Synthetic oil is really good stuff, but extended change intervals with any oil allows build up of microscopic particulate that is not caught by the oil filter. I would be interested to know what you find when you closely examine the chain. I would be interested in whether it failed because of metal fatigue or wear through.

BTW Agupta, this is neither a 16V or an 8V, it is a 12V. The 2.6 in the 190 is an M103 six cylinder engine, a smaller displacement version of the 300E engine.


Best of luck and keep us updated,
Reply With Quote
  #6  
Old 09-07-2001, 02:33 PM
agupta
Guest
 
Posts: n/a
Thanks for correcting me on the engine, Larry. I didn't know that in 89 they had the ratcheting type tensioner - many of them in the eighties worked on oil pressure, and when that leaked out, the chain became loose.

And ya, it would be useful to know what the reason for the failure was, and the symptoms it had, if any.

Rags.
Reply With Quote
  #7  
Old 09-08-2001, 12:15 PM
Southern_Son
Guest
 
Posts: n/a
At 230,000 I would change the rails as you are contemplating. Not only do the rails experience surface wear, but they become brittle with time, also.
Reply With Quote
  #8  
Old 09-09-2001, 04:38 PM
mplafleur's Avatar
User Friendly
 
Join Date: Sep 2001
Location: Lathrup Village, Michigan
Posts: 2,939
I don't know if I had any symptoms prior to the failure. The only noise I experienced is a clicking or ticking for about 2 seconds after startup. I thought this was valvetrain noise.

The tensioner is a rachet type and seems to still be operational. The rail on the right has some small pieces broken off, but this may have occured as a result of the broken chain. I don't think so, because the did not fully come off the camshaft.

The chain broke by pulling a link pin through the hole. I will try to attach a picture of the chain.

I have not turned the cam yet to see if it had siezed.
Attached Thumbnails
190E 2.6L  Timing chain broke-timing-chain.jpg  
Reply With Quote
  #9  
Old 09-09-2001, 04:50 PM
LarryBible
Guest
 
Posts: n/a
mplefluer,

Thanks for the picture. It sounds like things are; "so far, so good". I'm anxious to here if there is any damage to valves.

Did you figure out the ratcheting tensioner okay, and what I mean by pushing the plunger all the way through then starting it through again? Make sure you barely start the tensioner, so it's not too tight when you're putting the chain in place.

Does the point of chain failure appear to have worn through anywhere, or do you think it just stressed and broke?

I'm still crossing my fingers for you as far as further damage goes.

Best of luck,
Reply With Quote
  #10  
Old 09-09-2001, 05:34 PM
Southern_Son
Guest
 
Posts: n/a
Is it possible that your chain jumped a few teeth and then experienced interference of valve with piston which halted camshaft movement resulting in chain being pulled apart? This would not be a good scenario but may be probable under the circumstances.
Reply With Quote
  #11  
Old 09-09-2001, 05:46 PM
mplafleur's Avatar
User Friendly
 
Join Date: Sep 2001
Location: Lathrup Village, Michigan
Posts: 2,939
Good God, I hope not! I will know more when I get the chain off tonight. I still have to remove the lower cover. I wonder where the rest of the chain ended up and in what condition.

I am rebuilding the top end of my '83 Harley. The rear exhaust valve guide came out of the head and stuck to the valve stem. About half of the guide then was ground up into little pieces while it was pounded into the head. I have had to take apart the rest of the engine so I could rid it of the little bits of metal.

I'm hoping I won't have to do anything of this sort for this engine. While I have low oil pressure (less then .25 bar) when hot, I don't relish doing a bottom end yet.

BTW. I have always been very careful to keep the oil pressure to at least .75 bar when at idle. At RPMs above 800, the pressure is always above 1 bar and at speed it is 2.75-3 bar.
__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Reply With Quote
  #12  
Old 09-09-2001, 07:58 PM
Southern_Son
Guest
 
Posts: n/a
I feel your pain. I hope this is not the case on the car, too! I hope you get your Harley back on the road again soon.
Reply With Quote
  #13  
Old 09-10-2001, 08:52 AM
LarryBible
Guest
 
Posts: n/a
With the ratcheting tensioner on these engines, it would seem to be close to impossible for the chain to "jump". Of course, nothing is impossible, but I think this would be about as close as you can get.

mplefleur, you're wise for removing the lower cover to learn more. Be patient and hang in there.

BTW, I expect that the balancer on this car is indexed by two round pins, not a woodruff key. If it is, you will need to put it back in place without the pins, then put the pins in place. Too many people just drive these things on with the pins in place by turning the crankshaft bolt. Many engines/crankshafts have been ruined by this method. Proceed carefully. I have not removed the balancer all the way from an M103, but the diesels are like this, so I just wanted to warn you about this while I'm thinking about it.

Good luck,
Reply With Quote
  #14  
Old 09-10-2001, 09:08 AM
mplafleur's Avatar
User Friendly
 
Join Date: Sep 2001
Location: Lathrup Village, Michigan
Posts: 2,939
I've just read some of your earlier posts regarding the process of installing the balancer. I understand the need to get it aligned perfectly, but why install it without the pins? Won't they stop the rotation as you draw the balancer in with the bolt? If it has to be done without the pins, no wonder it takes 20 tries.

BTW. When I removed the crank compensating sprocket on my Harley, I used a 1 1/2" socket on a 3/4" breaker bar and an 8 foot cheater bar. I had to use everything I had with someone sitting on the back on the bike to stop it from lifting off the ground. The spec says 320 ft-lbs, but I think this was a tad more.
__________________
Michael LaFleur

'05 E320 CDI - 86,000 miles
'86 300SDL - 360,000 miles
'85 300SD - 150,000 miles (sold)
'89 190D - 120,000 miles (sold)
'85 300SD - 317,000 miles (sold)
'98 ML320 - 270,000 miles (sold)
'75 300D - 170,000 miles (sold)
'83 Harley Davidson FLTC (Broken again) :-(
'61 Plymouth Valiant - 60k mikes
2004 Papillon (Oliver)
2005 Tzitzu (Griffon)
2009 Welsh Corgi (Buba)

Reply With Quote
  #15  
Old 09-11-2001, 09:52 AM
LarryBible
Guest
 
Posts: n/a
If the pins are close to being aligned but not properly aligned, it is such a big bolt, it will just force it down into place and will shear part of the pin and slot off, not a good thing. There have been several crankshafts and balancers ruined in this way.

I said twenty tries. Now that I know to offset it a little to let it rotate slightly while it is being drawn into place, I could probably do it in just a few tries now. Nothing like practice.

Have a great day,
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
timing chain rails - is it enough? rsmcmahon Tech Help 4 10-29-2003 12:39 PM
Timing Chain takes out another 420SEL RobertG Tech Help 15 01-09-2003 03:24 PM
When Timing chain broke Mechanic says it was from PKash Tech Help 11 06-09-2002 12:12 PM
500E Timing chain replacement dwight hinton Tech Help 12 07-24-2001 01:06 AM
190E dual timing chain retrofit. Andrew Fritze Tech Help 1 06-02-1999 09:06 PM



All times are GMT -4. The time now is 11:31 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2011 Pelican Parts - Posts may be archived for display on the Peach Parts or Pelican Parts Website -    DMCA Registered Agent Contact Page