Merc 190E timing chain failure

[Merc190EBX]

Hello people. Im new on here and I have had a serious failure on my 190. The timing chain has snapped. I have already ordered a Haynes manual and a new chain but am anxious to know whether im going to be able to do it myself. I was hoping someone on here would know something about it. All I know is that it is an early 190e (c reg), and so has the single chain (simplex) type chain camshaft drive, as opposed to the maintainance free duplex type used on later models. Basically the car has been sounding very rough for a while so ive been foolish in not sorting it out sooner. The sound can only be described as a dull yet tinny tapping sound that sounded totally out of time to the speed of the engine (a lot slower), yet quite rythmical. It sort of went, 1,2,3,4, 1 and 2, 3,4 if you know what I mean? When it snapped, I just thought I had run out of fuel, and was only doing 1500 RPM up a hill. I only realised it was more serious when I tried to start it again- rather than the normal car starting sound, there was a constand humm (no compression due to valves being in wrong position I expect) It was rather annoying timing as it was the same day I took the engine out of my other pride and joy (my Citroen BX). Speaking of timing, I guess thats what im most concerned about when putting a new chain on- Are there any timing marks for example, and do I need any special Mercedes tools?

Thanks in advance for any replies, regards, Adam

 

[mike65]

To be honest if your asking these questions it suggests you bite the bullet and get a garage to do the work. Or scrap the car (parts may be worth quite a bit).

When the timing chain goes its more than a new chain you need, the valves and pistons wont be too happy either. Mucho work may need doing there, the cost of parts and labour (even your own) means a 20 year old car is simply not worth repairing.

Mike.

 

[television]

If the car was an auto,you may get away with a couple of bent valves, maybe not even that, taking off the head will reveal all.

With an auto, the engine cuts, with a manual the over run does the damage.
Many years ago auto's had a rear pump that meant they could be tow started. this car would not have one, interesting to see that they are being fitted again on some MB's.
good luck with it, keep your fingers crossed, and a couple of dents in the top of the pistons does not matter.

Malcolm

 

[Merc190EBX]

Thankyou for the advice guys. Im remaining optimistic. I know from rebuilding my BX engine, that on that particular engine, the was no physical posibility that a cambelt failure could cause internal valve or piston damage. Even when the pistons are at top dead centre and the valves are fully open, there would be a good 4mm between the valves and pistons. Im hoping the Merc engine is the same. Its the same era of engine, is only an 8 valve and has low compression compared to modern engines. The car is also an automatic, and at the time of failure I was only doing about 1500 RPM up a hill at 25 MPH. There was no banging sound either. It was as peaceful as running out of fuel. I have had a good read of my Haynes manual. Providing there is no internal damage, I should be able to set the crankshaft and camshaft to TDC and attatch the chain, then join up the remaining link (I believe the idea is to feed it on to the old chain, feed it round then re-attatch so that camshaft timing is not lost). Obviously thats chain failure prevention, I have got failure, so there is no set procedure in the Haynes manual so ill have to do a bit of cross referencing. BTW, if I do get it fixed, I have another problem- the auto box has been stuck in standard mode (S), rather than economy mode (E) for the last month or so. I hate this mode as its not nearly as smooth, uses more fuel, and if you want to go fast, youve got kickdown anyway, which overides economy mode. The Merc 190 seems to have a great gearbox (because of the E mode), but in S mode, it doesnt live up to most other autos I have driven. For example, when pulling out of a busy junction in the wet to turn right, I may use full throttle. The gearbox seems to start off in second, and then, when I have already reached 10-15Mph, it decides that first will provide more power, causing wheelspin which is quite dangerous.

 

[television]

As the head is coming off, is it wise to try and fit without taking off timing cover, the guides will need reseting and checked. The timing has been lost so no point. the sprockets may need replacing if they are worn. you could convert to duplex.

Malcolm

 

[Ian Brown]

Might be cheaper and quicker with a s/h engine, if there has been a lot of damage done on your own engine. Also you could get one from a later model with a duplex chain.