Cam timing tools for 1.2 engine

[Jonah]

Hi,

I'm thinking of changing the cambelt on the girlfriend's Bravo 80SX, so I'm wondering if anyone here has done the job and if you have any tips. According to the Haynes manual special tools are needed to set the cam timing, and these seem to be expensive, but can it be done without the special tools just by marking the positions of the pulleys / tensioner and fitting the new belt in the same position?

Alternatively, does anyone have these tools that they no longer need and would consider selling?

Thanks!

 

[steve]

I changed the cambelt on my brava 1.4.
The haynes manual required tools to hold the cam and crank in place so they did not move out of position.

I knocked my own up.
I made a toothed cowling that screwed into the rocker cover screw holes and engaged the cam.
and a bent bit of plate screwed into the crank pulley screw holes and some screw holes in the block to hold the crank.

With a lot of care it all went OK. I did not have to retime afterwards.

Obviously care is the key word.

 

[paul]

Re: Re: Cam timing tools for 1.2 engine

The 1.2 engine is the same as in the punto sporting which i have. Step 1 is to remove the plug in the cam housing. Slowly turn the engine with it in gear by pushing the car forwards until you find the slot in the camshaft by using your finger. When you find this put your socket set extension bar in the slot. It should fit perfectly.
Then put the car into first gear and ensure the car cannot move at all.
Remove all covers from engine, including exhaust heat shield and then mark cam position with permanent marker.
Then you are free to remove the belt. using the theory that if nothing has moved then the new belt should go straight on where the old one came off!!
Check the tension before you remove the old one so you know what the tension should be like.
I imagine the power steering pump is the same as the punto, dont try and slacken its mounts, just remove the 3 bolts holding the crank pulley. You can move the alternator though.
When new belt is in place make sure you remove the socket extension from the cam housing!!
If you have any more questions email me at [email protected]

 

[Deckchair]

timing belt change

Interesting as I'm about to change the belt and tensioner on my 1.2 80Sx without any special tools.
Quite obviously, if you take care and don't move the crank or camshaft sprockets and the two are in the same positions with the new belt and tensioner fitted then that is all there is to it.

The special tools are just finding the piston mid positions and locking up the camshaft at that position.

There are a number of ways you could go about it.

It's been suggested to cut through the existing cambelt around the circumference half way through so the sprockets are still engaged with the old belt, slip the new cambelt half way on,then cut through the old belt and remove. Then slide on the new belt the rest of the way. Simple if you can get access.

Another way is with the old belt still attached, find the pistons approx mid positions by removing spark plugs and dropping some long, identical length knitting needles or similar through the plug holes. Note heights and remove and rotate the engine by hand until they are all the same height by using a straightedge along the top of them. You now have the pistons aat the rough mid position and not able to collide with the valves.

Then you need to mark the crankshaft and camshaft sprocket positions, possibly with a simple small spirit level to help find and mark the vertical positions with something that isn't going to rub off.

Change the belt without moving the sprockets, recheck the alignment marks

Or you can do as said above and find and use the camshaft reference slot and mark the crankshaft pulley at that position.

With all methods, always fit a new tensioner, tension up, check your alignment marks, rotate the engine at least twice by hand. Check the marks and the belt tension again and then, pray to Mecca, get someone with a healthy bank balance to start the car!

Worth checking out the water pump for leaks while you're there and fit new alternator belt and power steering pump belts

 

[Jonah]

Re: timing belt change

Brilliant, thanks for all the tips. Sounds like it is entirely possible then without the special tools.

Couple more questions:
Is the bottom sprocket keyed to the crankshaft? Or does it rely on the pulley bolts being done up tight to keep its position? (in other words will the sprocket spin around freely with the outer pulley removed)
Is it vital to change the tensioner and how much does it cost? I've read that the plastic ones can shatter but that later versions used a steel roller... I had a quick peek through the top belt cover and it does look like plastic although I couldn't be sure. Anyone know for certain on a '99 1.2 engine?

Thanks again.

 

[Deckcahir]

info

Hi Jonah


No the crankshaft sprocket stays put, you only remove the crankshaft pulley which is held on by three bolts to the crankshaft sprocket

 

[Jim]

Re: timing belt change