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Cam timing woes

Hello all

I've just replaced the cambelt on the wifes car and now it wont start!

The car is a '99 1.3 VW chico: For those unfamiliar with South African models, this is a (mostly) standard 1.3 golf 1.

Any idea where I can get a picture at least of where the camshaft gear (with the dot) should be when engine is at TDC? At the moment with the crank pulley showing the ignition timing mark, there is no reference point on the tappet cover/head for the dot that is on the camshoft gear wheel.

I've done the following:

  1. Set engine (while the old belt was on) so that ignition marker on crank pulley was set to the arrow on the pulley cover.
  2. Marked off on the head where the camshaft gear wheel dot was (so if the crank and/or camshaft moved after I took the old belt out, I would still be able to line up everything.
  3. Removed old belt.
  4. Put new belt on (counted the teeth on it first, matched it up, etc).
  5. Checked that the dots lined up (It all looked OK).
  6. Turned engine with a spanner two full revolutions to make sure that even if I did something wrong, no permanent damage would result.
  7. Tried to start, starter just spun and spun but nothing more happened.

At that point, I kinda panicked, and remembered that prior to doing all of this, I had removed all the spark-plugs (and put them back in) to check the condition of the engine. I thought perhaps that I got the firing order wrong, and then tried to reset the firing order.

Car now backfires violently but still wont start.

So, the questions I have are:

  1. If I want to restart and set all the timings properly, is it sufficient to find TDC with a long straw in #1 plug-hole (or suchlike), set the camshaft (I have the tappet cover off now) for #1 so that both valves are fully closed (i.e. compression stroke), set the distributor so that

the rotor is at #1 wire and then set the firing order (I can't remember

what it is, though I can tell from the cams). Did I miss anything there?

  1. Where can I find a picture of a camshaft when the piston is on the compression stroke? I'd like one especially which shows where the "dot" on the camshaft gear should be.

  1. Are there *any* online sites that deal with technical repair (preferably with pictures) for the golf 1? I had no luck with a quick search on google as all the sites it found for me were for modders or modded cars. My car (AFAIK) is stock standard, and as I have no desire to do anything other than install a radio (for the traffic reports), these sites have little to offer me other than telling me how low the car can go, what the maximum wheel-size you can go to, etc ... and a whole lot of other information that I just cannot use.

  2. Anyone want to recommend a good manual? A friend of mine apparently has a golf 1/scirocco haynes manual, but its incomplete, and some of the pages have been lost, destroyed or just faded away to white.

TIA goose

Reply to
goose
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Hello all

I'm writing this down in the hope that it will help other home-mechanics who search google for an answer.

The problem I've found is that the cambelt also turns the distributor. When I replaced the cambelt, the gear which turns the distributor (off the cambelt) had turned, so the ignition timing was off.

Since I had already messed up the valve timing while trying to figure out what was wrong, I now had both the valve and ignition timing out, and the cambelt was off the engine.

  1. I "found" TDC by using a long screwdriver down the #1 cylinder. The procedure is to get the piston near TDC, and rock back and forth over TDC while the screwdriver was in the spark plug hole. I marked the point where the screwdriver stopped upward motion (turning the engine with a spanner), marked off the position where the screwdriver started going down and took the middle of the two marks as TDC.

  1. I set the distributor by merely spinning the toothed gear near the crank gear until the rotor was under one of the wires on the distributor cap (any wire will do, you then just call that #1).

  2. I turned the camshaft (spanner again) and "rocked" #4 (this means: turn the camshaft until the inlet valve and exhaust valve for #4 are just about to open/close. Ideally the cams would be holding the valves in the same position with no clearances). This ensured that I had #1 valves at the maximum clearance. I marked of this position on the outside of the head and the camshaft gear wheel.

  1. I then worked out the firing order from the valve positions for all the cylinders (on my car, this worked out to 1-3-4-2).

  2. I installed the new belt, making sure after the belt was tensioned that none of the gear-wheels had shifted position (which is why I marked them all off before starting) and that the tensioner was tight.

  1. I set the firing order on the distributor cap.

  2. I turned the engine with a spanner two full revolutions. This I did to check whether any of the valves were going to touch the pistons. If you turn the engine like this first, then at least you won't damage the valves because you'll feel the resistance if a valve touches a piston.

  1. I started the car (it started on the first turn off the key - YAY!!!)

  2. I then switched the car off, and set the ignition timing statically; This is done by turning the engine until the timing mark is visible and near the point of reference on the cambelt cover and when #1 is getting ready to fire (i.e. the rotor must be about to fire #1). I took a spark plug, put it on the #1 wire, held it against ground and twisted the distributor back and forth until I got a spark on the plug (obviously the ignition must be on while you do this). I turned the distributor and set it at the point that a spark was produced. This is good enough to ensure the car starts.

Later this week, once I fix the leads on my timing light, I'll set the timing proper for unleaded petrol.

Whew... Hope that this post is helpfull to anyone else with a 4-cylinder watercooled VW - AIUI most of the VW engines from 80's & 90's have the same design, with the cambelt controlling the rotor (first car I've worked on that had this arrangement was this car! All the others had a different crank-gear or cam-gear arrangement for turning the rotor); hopefully anyone else who runs into the same problem will read this (google is your friend:-) and realise that the cambelt is on proper, it's just the rotor thats off.

Later all,

goose

Reply to
goose

sounds like you put the cam & belt back together correctly..may have mixed up the firing order on the plug wires tho.

Reply to
David

Hello all

I'm writing this down in the hope that it will help other home-mechanics who search google for an answer.

The problem I've found is that the cambelt also turns the distributor. When I replaced the cambelt, the gear which turns the distributor (off the cambelt) had turned, so the ignition timing was off.

Since I had already messed up the valve timing while trying to figure out what was wrong, I now had both the valve and ignition timing out, and the cambelt was off the engine.

  1. I "found" TDC by using a long screwdriver down the #1 cylinder. The procedure is to get the piston near TDC, and rock back and forth over TDC while the screwdriver was in the spark plug hole. I marked the point where the screwdriver stopped upward motion (turning the engine with a spanner), marked off the position where the screwdriver started going down and took the middle of the two marks as TDC.

  1. I set the distributor by merely spinning the toothed gear near the crank gear until the rotor was under one of the wires on the distributor cap (any wire will do, you then just call that #1).

  2. I turned the camshaft (spanner again) and "rocked" #4 (this means: turn the camshaft until the inlet valve and exhaust valve for #4 are just about to open/close. Ideally the cams would be holding the valves in the same position with no clearances). This ensured that I had #1 valves at the maximum clearance. I marked of this position on the outside of the head and the camshaft gear wheel.

  1. I then worked out the firing order from the valve positions for all the cylinders (on my car, this worked out to 1-3-4-2).

  2. I installed the new belt, making sure after the belt was tensioned that none of the gear-wheels had shifted position (which is why I marked them all off before starting) and that the tensioner was tight.

  1. I set the firing order on the distributor cap.

  2. I turned the engine with a spanner two full revolutions. This I did to check whether any of the valves were going to touch the pistons. If you turn the engine like this first, then at least you won't damage the valves because you'll feel the resistance if a valve touches a piston.

  1. I started the car (it started on the first turn off the key - YAY!!!)

  2. I then switched the car off, and set the ignition timing statically; This is done by turning the engine until the timing mark is visible and near the point of reference on the cambelt cover and when #1 is getting ready to fire (i.e. the rotor must be about to fire #1). I took a spark plug, put it on the #1 wire, held it against ground and twisted the distributor back and forth until I got a spark on the plug (obviously the ignition must be on while you do this). I turned the distributor and set it at the point that a spark was produced. This is good enough to ensure the car starts.

Later this week, once I fix the leads on my timing light, I'll set the timing proper for unleaded petrol.

Whew... Hope that this post is helpfull to anyone else with a

4-cylinder watercooled VW - AIUI most of the VW engines from 80's & 90's have the same design, with the cambelt controlling the rotor (first car I've worked on that had this arrangement was this car! All the others had a different crank-gear or cam-gear arrangement for turning the rotor); hopefully anyone else who runs into the same problem will read this (google is your friend:-) and realise that the cambelt is on proper, it's just the rotor thats off.

Later all,

goose

Reply to
goose

should of had the manual before you opened the hood!

Reply to
Lost again

The Bentley calls that the intermediate shaft. It runs not only the distributor, but also the oil pump.

Glad you got it sorted -- thanks for the info.

Reply to
tylernt

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