Author Topic: Timing chain, loose or not ?? (pics and video) (Read 7953 times)

Frankie · « **on:** December 30, 2007, 01:49:44 PM »

Well, I just took off the valve cover to check whether the timing chain is loose or not. There has been a metallic hissing/rattling noise from the engine which I cannot locate accurate.

To my eyes the timing chain does not look worn? (278 000 kilometers on the clock). Pics --> http://picasaweb.google.co.uk/keimo12/NimeMTNAlbumi

Video shows how much the timing chain moves, is that too much? Video --> http://www.youtube.com/watch?v=_c-k6LhY3ss

sheepdog · « **Reply #1 on:** December 30, 2007, 06:53:53 PM »

It will be loose as long as the tensioner is not pumped up with oil. It automatically tensions it.

You are lucky, looks like somone already went through and replaced your tining system. May want to consider replacing the tensioner, but otherwise those are some very new looking sprockets, which is how you can tell how bad th chain is. When they are sharp enough to cut, time to replace everything. Those are not even showing wear.

Not sure what the hissing sound is, mine is doing similar, I suspect the fan clutch or water pump.

bosox1134 · « **Reply #2 on:** December 31, 2007, 07:24:20 AM »

how do i change the tensioner

RED IS 91 · « **Reply #3 on:** December 31, 2007, 07:32:57 AM »

http://m42club.com/forums/showthread.php?t=2925

Frankie · « **Reply #4 on:** December 31, 2007, 08:03:00 AM »

Quote from: sheepdog;40176

It will be loose as long as the tensioner is not pumped up with oil. It automatically tensions it.

You are lucky, looks like somone already went through and replaced your tining system. May want to consider replacing the tensioner, but otherwise those are some very new looking sprockets, which is how you can tell how bad th chain is. When they are sharp enough to cut, time to replace everything. Those are not even showing wear.

Not sure what the hissing sound is, mine is doing similar, I suspect the fan clutch or water pump.

I have already replaced the lower tensioner. What about other tensioners, can those be changed without all the timing hassle? Meaning that I would not like to get involved with cam timing.

sheepdog · « **Reply #5 on:** December 31, 2007, 02:07:51 PM »

Quote from: Frankie;40205

I have already replaced the lower tensioner. What about other tensioners, can those be changed without all the timing hassle? Meaning that I would not like to get involved with cam timing.

There is only one tensioner, the other sprocket is an idler.

Frankie · « **Reply #6 on:** January 01, 2008, 06:47:47 AM »

According to this pic, I can change parts 6, 7 and 14 without messing the timing?

swiss318is · « **Reply #7 on:** January 01, 2008, 08:19:53 AM »

hello.. i am new in this forum and so i wanted to say hello to everybody. i reading this forum for a while and there are a few very interesting things. i am actually living in switzerland... so forgive me my bad english.
i have got 3 complete 318is e30 and a 4th complete engine/gearbox/m3diff

swiss318is · « **Reply #8 on:** January 01, 2008, 08:28:37 AM »

hey frankie. there is a point on the flywheel. you can see it through a hole of the gearbox, normally closed with a rubbercap.( have a look from the front to the back of the car.) turn this point down and then mark the cams and dont move them anymore. now you can remove everypart you want without messing the timing. i have done this many times before. usually you only have to replace the tensioner. the rest longs thousands and thousand of km. in my new engine i dont even have a tensioner anymore. it is a big screw.. it is fixed and cant move anymore.

romkasponka · « **Reply #9 on:** January 01, 2008, 11:00:54 AM »

What do you think about adjustable cam chain tensioners?

sheepdog · « **Reply #10 on:** January 01, 2008, 12:43:32 PM »

Quote from: Frankie;40234

According to this pic, I can change parts 6, 7 and 14 without messing the timing?

17 as well.

sheepdog · « **Reply #11 on:** January 01, 2008, 12:46:15 PM »

Quote from: romkasponka;40251

What do you think about adjustable cam chain tensioners?

Why, you already have an automatic one.

An adjustable one means you would have to maintain it, and you do not know how much slack would be too much or not enough. Either is very bad.

swiss318is · « **Reply #12 on:** January 01, 2008, 01:10:37 PM »

a friend of mine is driving his m3 e30 race car succesfully without the normal tensioner (nr17 on the picture above) its only a big screw. that works without problems.. and the engine makes about 330hp.. not 136hp, like the 318is :-)

swiss318is · « **Reply #13 on:** January 01, 2008, 01:19:16 PM »

the reason behind the story is, that on high hp engines and above 9000-10000revs the chain, with the normal adjuster (with a spring), can jump over the sprocket on the crank or on the cams...!!! an then you have 16 small problems.... ;-) with the screw, nr 14 is fixed and anything moves.

romkasponka · « **Reply #14 on:** January 01, 2008, 01:21:37 PM »

can you get a picture or drawing? for sportbikes it is very simple so I think it is posible to make one for M42 too..

Because I saw M3 engine for sale and there was written:

Totally rebuild complete S14 Rally engine Pistons: 95 mm W�ssner (Germany) (new) 2.3 crank, 2.380 cc, Rods: Verdi(Sweden), Cams: K�hler (Sweden, kohler racing)12,5 mm / 11.8 mm 305/285 , Valves BMW M5 (38,5 mm / 33 mm) , Cam tappets: Schrick, Valve springs: Schrick, Valve spring retainers: BMW motorsport (titanium), Lash caps Schrick, The head is fully ported, 48 mm throttle bodies BMW, Header: 4-2-1 (Rally spec.), Adjustable cam chain tensioner, Bosch ref/sync sensors, BMW motorsport sync sensor holder (inlet cam front end), Generator (new), Starter motor, Full service for head is done , Power band 3500-9000 rpm. Very good driveability. High Torque,power.