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Thebmwbum, BMW Foreman
Category: BMW
Satisfied Customers: 715
Experience:  31 years BMW Experience
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1999 BMW 740il timing chain guide repair information. Is it

Customer Question

1999 BMW 740il timing chain guide repair information. Is it necessary to replace the chains? Do I have to completely disassemble the engine as if I were replacing the chains? I believe the timing chains have not jumped teeth yet. It is rattling and set check engine light for timing A code if I remember correctly.
Submitted: 7 years ago.
Category: BMW
Expert:  hauto replied 7 years ago.

when you replace the chain guides you should replace the chain too.

you don't have to disassemble the engine for this, but this is a big hard job with lots of details and work. and no room for mistakes. this requires experince and knowledge of the motor.

Most of the time when a code is stored it's usually for the variable valve timing solenoid

not the chain.

Customer: replied 7 years ago.
I'm looking for someone who has actually performed this repair. I am a GM tech with 25 years experience and I would like to be communicated to with more detail. The disassembly I was refering to was for the timing chain itself. I would also like to know if it is a common problem. If it is and you are a BMW tech you can truly tell me if just the guide will do. What would you do? I'm looking to fix and sell the car so I want to go the least expensive route. I will replace the chain if stated so in the BMW service manual. Is there also something I need to look out for with the chain tensioner? I was wondering if there was a short cut. I've seem to had heard a rumor about it. I realize the required time and special tools needed. The code stored was for timing chain out of time and not for a solenoid. Seeing as it's saturday and I'm not at work and I did not write down the code I can't go into further detail. As for the current answer I am not yet satisfied.
Expert:  hauto replied 7 years ago.

Hello again. I have done this job quite few times I wasn't aware that your a tech. But even though this is a much harder task even for techs that have no foreign car experience

as for the chain I have not heard about replacing the guides alone I think that would be

a waste of time, specially when you say there is a rattle. Your a tech would you replace the guides on a gm motor and leave the chain. To me I think not.

AS far as communication with BMW tech I am willing to give you all the advise and help

but if your looking for step by step question answer on the removal, that I couldn't do. I could send you the removal instructions if you'd like.

If you want me help please reply, If you'd like me to opt out and have another BMW tech

help I will too. I just want to see get the help you need so you can get going.

thank you.


Customer: replied 7 years ago.
All right then, since I was not really satisfied with the first two responses due to the fact I could have come up with those answers myself and those seamed to be of no technical help to me. Answer me these questions and I will accept your response (after checking to be sure I wasn't already charged). Why did you perform the timing chain repairs to begin with? What was broken and/or damaged with the timing chain, guides, etc..? Thank you for the offer of step by step instuctions but I already have access to service guides.
Expert:  Thebmwbum replied 7 years ago.


For rails you will have to remove the front cover ,generally these last fairly well into the life of the motor.Unless it' s of course been neglected.

But if your more after noises ,the vanos units themselves will give a low level knock sound when stuck,and sometime a fault which you indicate you have a timing reference fault.may indicate a need for that vanos

Then you'll need all the lock blocks and locater's

But look into the oil cap (if you haven't disassembled yet ) see if this is sludged over

Another indicator (quick) is remove the oil filter,if you see metal then the Bakelite is blown off the rails.

if that looks good ,oddly enough check the plugs when they are loose you get some odd noises like the cam is broke

for the timing fault move the intake cam sensor (swap them) see if it follows it ,they frequently go bad,( I'm only familiar with the BMW software codes so any other won't help me)

Hope this helps

Good luck with your project



Thebmwbum, BMW Foreman
Category: BMW
Satisfied Customers: 715
Experience: 31 years BMW Experience
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