Cambelt Stress

[Craggy73]

Decided to take advantage of the warmer weather and change my cambelt today, with the help of a guide off E30world. All seemed to go well with some struggles stripping it down. Took me 6 hours to do the lot. I've started the car up and it's mis-firing and popping. The timing is obviously out. When I aligned the cam pulley I couldn't see the guide arrow, the centre of the pulley looked smooth, so I used a small groove that was on the side of one of the teeth. I'm sure this is where I've gone wrong. Will get it stripped down again in the morning with the hope of fixing it.

[bmw9818]

my one was a bit out and running fine, are your ht leads in correctly? when the cambelt was put on it was lined up however once turned the cam was a few degrees out, i was worried but my ol man said not to worry it fired up fine and running smooth!

my one misfired etc cause my ht leads were in the wrong order,

[Craggy73]

Sounds like you got off lightly. I turned the crank with the new belt on and it still lined up ok. I had to unplug the HT leads but did number them so they went back in order. I'll check them first then will try to remove as little as possible and see if I can turn the pulley in one direction by one tooth on the belt to see if it aligns. If it's worse I'll turn it back 2 teeth and see if that sorts it. It must only be a fraction out.

[Grrrmachine]

The guide for which engine? There are guides in the Wiki that are spot on, with pics.

[Craggy73]

It's for the M20. I've got a 325i

[Grrrmachine]

Here you go:

http://www.e30zone.net/e30zonewiki/inde ... elt_Change

First cam belt change caught me out too. I wasn't expecting the lower timing mark to be on the TOP (i.e the edge) of the crank wheel, so I was looking for it on the front face, so I had mine lined up wrong too.

[Craggy73]

I've just been out and checked the leads first. Thankfully, this donkey had just put two of the HT leads on the wrong way round. I can crack a smile again

[polsta]

how long should it take ? had a look the other night round my mates on some software hes got on computer, it said change every 2 years regardless of milage, and about a 2 hour job on a 325i ?

[Kedge]

how long should it take ? had a look the other night round my mates on some software hes got on computer, it said change every 2 years regardless of milage, and about a 2 hour job on a 325i ?

2hr job for a proper grease monkey who's just ripping it apart and chucking it back together. Taking your time and cleaning things up as you go I'd say you'd probably double it.

The actual belt change is dead easy, it's just time consuming removing the casing and water pipes and all the other stuff in the way. On top of that the M20 is notorious for taking a good while to bleed the coolant proparly.

[daimlerman]

how long should it take ? had a look the other night round my mates on some software hes got on computer, it said change every 2 years regardless of milage, and about a 2 hour job on a 325i ?

Depends on how good you are with the spanners and if you break any fittings!

Cambelt change takes me about two hours or so,I allow half a day.

Should be changed every three years or 30k miles.Also a very good to swap the water pump every second belt change.

[Speedtouch]

I did my first ever cambelt change on a Tech 2 325i Sport, working outdoors in cold weather, and it took about 3-4 hours in all.

[Rtaylor2208]

It took me all weekend the first time around, but I spent alot of time, checking and rechecking things. The biggest headache for me was finding the TDC mark on the balancer, it was on the back of the bloddy thing so could not find it as per the wiki.

Satisfying job once done but its a bit of a PITA.

I think 2 hours would be a real push to get it all done I would say 3 to 4 hours for a knowledagle mechanic thats knows the M20.

Definetly a DIY job as long as you have ramps, a 32mm spanner for the fan and a half decent socket set.

[Craggy73]

I would say 3 to 4 hours minimum if you are following a guide. That's what assumed but if you then struggle getting parts off, like I did, then it can easily stretch out. Give yourself a full day to be certain. If parts haven't been removed for many years they can be a little reluctant to budge at times.

[G-Bear]

Got the box of parts in my loft.. I'm quite looking forward to this job..

[Budgie325]

I'll be doing mine this weekend also i think.

[polsta]

what sort of parts would you clean up on the way ?

basicly engine need a full spruce up and service of everything, was 100% mechanicly before i took it off the road about 18 months ago and had a belt change and new distributor and things not long before i bought it, but it will be near on 2 years off the road by the time its back on the road

[Andyboy]

New belt and tensioner - it all comes in an SKF or Gates belt kit. I also replace the tensioning spring as it's been in there 20 years and will have lose some tensioner after being under compression for so long. It's worth replacing the pump for the sake of 25 quid. With the pump off you can clean the front of the block nicely with a scraper followed by degreaser and a brush and then a rag to dry it and wipe it clean. You also need an old toothbrush and a can of aerosol carb cleaner to clean all the crap out around the crank sprocket. You can do it in a couple of hours but I always replace the camshaft oil seal as well as the cam cover gasket and D seals, take the radiator out and give it a reverse flush etc and that adds time.

[Simon13]

you can be really motorsport and change it leaving the rad in and not touch the cooling system. But you need small hands as it gets a bit tight this way!

[Andyboy]

you can be really motorsport and change it leaving the rad in and not touch the cooling system. But you need small hands as it gets a bit tight this way!

Knuckes ragged against the sharp rad fins. No ta!