m40 cambelt help

[benurminge]

Hi there,
I have a 318i m40 touring. I am getting it on the road as my daily on the 1st of jan. Its got 145,000 on the clock and according to the history it hasn't had the cam belt changed since 80,000!!
I want to learn how to do it myself but i am not a mechanic.
Is there anyone in the south of England (hour away from Southampton max) who has done this cambelt change before and has the special tool required who doesn't mind giving up one Saturday to change my cam belt for money of course. I
Il rather give money to a fellow e30 lover who can teach me then some overpriced garage.
Please someone help me.
Contact through here or my mobile would be best. 07787227815

[Brianmoooore]

Haynes manual has a good DIY run through of an M40 belt change, which shows you how to tension the belt using a cheap spring balance.
You can use a drill bit (8mm? - can't remember. Use one that fits tight) to lock the flywheel at TDC, and a ruler along the top flat of the camshaft will do instead of the locking tool. The cam won't move with the belt off unless you move it.
I consider that resetting the cam pulley on the end of the camshaft is usually unnecessary. It won't be far out unless someone has been there before and set it wrong.
Don't over tighten things. Far more problems are caused by over tightening fasteners than by under tightening them.

[Billwill]

You can purchase the Haynes Manual, manual 1984...BMW 3&5 Series Service and Repair Manual or look for it online.

As Brian has stated you lock the engine at TDC by inserting an 8 mm bolt or rod...you can use the lever bar in the toolkit normally used in conjunction with the Spark Plug spanner...this goes through the Bellhousing just behind the starter motor....you may have to turn the engine over 360 degrees to be at the correct TDC.

When you fit the new belt...and new tenshioner and new idler pulleys....you use a small fish scale to pull on the allan-key used to adjust the tenshioner...but at a distance of 85 mm and 2.0 KG on the small fish scale. At this stage you need to check that the camshaft is level with the top of the head using a straight edge and a vernier..if it is not level loosen the Torx bolt on the cam, get it level and torque to 65 nm. Turn the engine over a few times at the crank with a 22 mm socket and re-check the camshaft position.

If you do a search in the "E30 Wiki" section here for "M40 cambelt" the procedure is explained basically exactly as the Haynes Manual states but without the final leveling of the camshaft and torquing up....I personally think this final stage is important!

[Andyboy]

Firstly: you don't need any kind of special tool to tension the belt unless you really haven't ever changed a belt before. Normally being able to just about twist the belt through 90 degrees on its longest run is fine. I and hundreds of others have been doing it this way for a long time. I used to think the special tensioner was important - it's not. It's an old single cam unit that doesn't rev particularly highly. You never used a tension gauge to do a Ford Pinto or Vauxhall OHC belt and the M40 is no different. The last one of these I did was some time ago - 2009 to be exact on a 1992 316i E36. 40 odd thousand later it's still running.

However I would always loosen the cam sprocket bolt and lock the crank and cam in place - in the past I've successfully used a setsquare to get the cam in the right place, but the proper cam lock tool is only a tenner these days. Whilst Brians method would be okay for a first belt change, these are old cars now that have had a succession of craftsmen with whitworth socket sets bodging away, so don't assume the cam timing is correct.

[Brianmoooore]

I consider that resetting the cam pulley on the end of the camshaft is usually unnecessary.

I'm not suggesting that you don't bother checking the timing (by laying a straight edge across the top of the cam), just that you don't slacken off the cam pulley as a matter of course.

[benurminge]

Okay guys I really appreciate all this help my certInly is still going over my head. Unless I am shown in person I am certainly not confident enough to do this cambelt on my own following either the haymes mannial or e30 wiki as I amnot a mechanic although I do alot on the car myself I have never changed a belt.
You can say its easy but everything is when you no what your doing.

Like I said if anyone is free anytime soon in the south area and wants to earn some money on thier weekend give me a shout

Cheers again.

[Billwill]

Yes if you are not comfortable doing the work yourself it is a wise move to get some help....a snapped or slipped belt is very expensive!

[Andyboy]

I would also replace all three rollers but be careful on cars built after December 1990 because they have the adjuster pulley from the E36 type M40.