Idiot Proof Guide to Changing Cambelt

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The Hairy Camper
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Idiot Proof Guide to Changing Cambelt

Post by The Hairy Camper »

Hi people, i've bought a 1.9 1Y engine to replace my 1.7 KY.

While i have the 1Y engine out i want to change the cambelt, tensioner etc. I've never done it before and i'm wondering if there is an idiot proof guide on the forum? Or if i should just find a mechanic before i break something?

Any advice on special equipment i may require? E.g Cam Pulley, Crank Lock?

Cheers.
1984 Autosleeper, pop-top, 1.7 KY, 5-Speed

colinthefox
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Re: Idiot Proof Guide to Changing Cambelt

Post by colinthefox »

It's actually easier to do with the engine in the van than out.
The reason is that with the engine out, it's quite difficult to find an accurate TDC for the crank to set everything up. With the original van flywheel, clutch and gearbox fitted, the timing marks on the clutch cover can be seen through the hole in the bellhousing. It's almost as easy to get at everything in the van as out anyway. Leaving the silencer off will give you a bit more room to get at the pulley bolts.

You'll need a kit consisting of cam timing plate, pump locking tool, and crank locking tool which you can find on eBay (although it is possible to do it without). My top tip is to tie a pretty ribbon onto the pump locking tool so you don't leave it in place accidentally when you start the engine. You'll also need a cam pulley holding tool which you can make easily or buy, and a dial gauge with an adaptor for the pump (if you have a Bosch pump).

There are two kinds of pump pulleys, namely single piece and two piece, and the method of adjustment is different for each. Don't loosen the centre nut until you know which type you have.

A photo of the pump and one of the pump pulley would be good.

You can certainly do the job yourself, but you do have to understand what you are doing before you get started.
1.9D (AEF) pop-top. Aaaaahhhhh........that's better.
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The Hairy Camper
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Location: Cheshire

Re: Idiot Proof Guide to Changing Cambelt

Post by The Hairy Camper »

colinthefox wrote:It's actually easier to do with the engine in the van than out.
:lol: I was told the opposite :shock: I doubt it would be a problem to install the 1Y and then start to do the belt change though?

Thanks for the reassurance Colin. I will have a look for those tools. Are there any good write ups or videos out there to explain whats involved? I've just come across this video which looks pretty good?
https://www.youtube.com/watch?v=UGgJaWzjCSk" onclick="window.open(this.href);return false;
1984 Autosleeper, pop-top, 1.7 KY, 5-Speed

colinthefox
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Re: Idiot Proof Guide to Changing Cambelt

Post by colinthefox »

That video is as good as it gets. Notice he had a spare gearbox to bolt on so he could find crank TDC! That's why it's easier in the vehicle.

If your engine has been running OK you could replace the belt "notch for notch" with crank set at TDC, then carefully check the cam and pump timing. They should be spot on, but if small adjustments are required you can do them then. That's how I do it if I'm sure I was the last person to replace the belt, because these belts are made to such tight tolerances it won't be far out IF IT WAS DONE PROPERLY LAST TIME. But I do always check!

Never, ever change the cam belt without renewing the tensioner. An old tensioner can throw the belt off line and cause disaster.

Also always replace the four Allen headed bolts on the crank pulley with new, as they are difficult to remove if rounded out.
1.9D (AEF) pop-top. Aaaaahhhhh........that's better.
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