Cambelt replacement - can I do it...

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TheStinkyHippy
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Cambelt replacement - can I do it...

Post by TheStinkyHippy » Wed Jan 13, 2016 2:18 pm

So, I have no record of when my Bongo had (if ever) a cambelt change.

Its a 2.5 diesel, 1995 model.
I've just ordered a replacement belt and tensioner.

I have successfully DIY performed the following;
oil changes, fuel filter changes, glow plug changes, diff oil changes

Reading http://www.igmaynard.co.uk/bongo/member ... ambelt.pdf

it seems kind of ok to do... but will I be able to do it?


If so, I have a couple of questions on the pdf..

1. It indicates, The torque settings are as follows:
• Camshaft sprocket/gear 123 – 140 nm
• Camshaft carrier/cap 12 – 14 nm

but doesn't mention those items in the document. So what do I need to use the torque settings for?
The only item I see I need to undo is the tensioner. (apart from all the bolts holding everything together)

2. The document has a section called 'Wheely easy' indicating to get access to the timing marks on the flywheel. I don't think I need to do that do I if I line up the fuel injector pulley and the crank using their timing marks.


Anything else I should think about.. any extra hints.

Many thanks all.. lets hope I don't murder my van..
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jimmo62
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Re: Cambelt replacement - can I do it...

Post by jimmo62 » Wed Jan 13, 2016 4:05 pm

I'd say the main hint is to turn the engine over by hand (spanner on the crankshaft pulley) several revolutions before you fire it up to check nothing is interfering. Also check the timing marks really carefully on disassembly and reassembly - several times - and get a second opinion if you have someone around.
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Re: Cambelt replacement - can I do it...

Post by Bob » Wed Jan 13, 2016 4:13 pm

I don't know if its practical to cut half of the cam belt away and remove, then slide the new one on half way before removing the rest of the old one, thus no movement.

Obviously still check the timing marks to be certain.
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Simon Jones
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Re: Cambelt replacement - can I do it...

Post by Simon Jones » Wed Jan 13, 2016 8:04 pm

Bob wrote:I don't know if its practical to cut half of the cam belt away and remove, then slide the new one on half way before removing the rest of the old one, thus no movement.

Obviously still check the timing marks to be certain.
The pulleys have sides on the them to keep the belt centred (as seen on the injector pump) so it would be risky to try in case the new belt gets damaged. It's not a huge job to change but you will need a big socket (38mm?) to turn the crankshaft round.

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Here you can see the camshaft pulley is the same:

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Northern Bongolow
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Re: Cambelt replacement - can I do it...

Post by Northern Bongolow » Wed Jan 13, 2016 9:00 pm

be careful when removing the elbow on the inlet manifold, this wraps round the front of the belt cover, the 2 bolts that mount the egr pipe are crappy threads and are easily stripped.
TheStinkyHippy
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Re: Cambelt replacement - can I do it...

Post by TheStinkyHippy » Sat Jan 16, 2016 9:30 am

Anyone have any idea what these tension values are for?

It indicates, The torque settings are as follows:
• Camshaft sprocket/gear 123 – 140 nm
• Camshaft carrier/cap 12 – 14 nm
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Simon Jones
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Re: Cambelt replacement - can I do it...

Post by Simon Jones » Sat Jan 16, 2016 11:41 am

As I recall you don't need to touch either of those items unless you are removing the camshaft.
teenmal
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Re: Cambelt replacement - can I do it...

Post by teenmal » Sun Jan 17, 2016 11:40 am

Yes you can do it if you are confident enough, even the "Experts" have been known to take their vehicles to a garage to have timing belts replaced because of lack of confidence.
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Re: Cambelt replacement - can I do it...

Post by haydn callow » Sun Jan 17, 2016 9:58 pm

Bob wrote:I don't know if its practical to cut half of the cam belt away and remove, then slide the new one on half way before removing the rest of the old one, thus no movement.

Obviously still check the timing marks to be certain.

That's the way I have done it. Used a Stanley knife with it ticking over....however you are taking a risk so don't blame me if it all goes wrong.
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Re: Cambelt replacement - can I do it...

Post by teenmal » Sun Jan 17, 2016 10:51 pm

haydn callow wrote:
Bob wrote:I don't know if its practical to cut half of the cam belt away and remove, then slide the new one on half way before removing the rest of the old one, thus no movement.

Obviously still check the timing marks to be certain.

That's the way I have done it. Used a Stanley knife with it ticking over....however you are taking a risk so don't blame me if it all goes wrong.

On
What vehicle did you change the belt using that method?
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Re: Cambelt replacement - can I do it...

Post by haydn callow » Sun Jan 17, 2016 10:59 pm

Hyundai Accent .... A old school mechanic showed me how to do it.....surprisingly easy, he did it on a Volvo
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Simon Jones
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Re: Cambelt replacement - can I do it...

Post by Simon Jones » Sun Jan 17, 2016 11:59 pm

With the 'shoulders' on the pulleys I can't see that method working on the diesel Bongo engine unless the tension was released to allow it to pass over the increased diameter. If you line everything up before removing the old belt, there is minimal chance of crankshaft, camshaft or injection pump moving on their own to cause the timing to be out. The manual shows that you need to take the crankshaft through two revolutions to allow the tensioner to settle and then you double check the timing marks again.
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Re: Cambelt replacement - can I do it...

Post by Titan1995 » Mon Jan 18, 2016 8:19 am

Not all that hard to do.

One thing that does make life easier if you make up a tool to pull the sprint tensioner onto the fixed post.

I have one that I made 35yrs ago, just 8mm bar ground down to a point one end then rolled into a hook, with another piece of bar welded across the shaft making it into a T .

I am sure that there are propriety tools around, so much easier than try to use pliers.

I find it easier to use the marks on the flywheel that you can see by removing the access plate behind the transmission bell housing.

Another thing I use a small USB camera poked through the observation hole near the fuel pump to check on the timing there, again better than a mirror.
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