1984 - 2.5 N/A Timing issue

Hi folks, after my timing belt snapped yesterday. My friend and I have come across a problem when replacing it. The CAMSHAFT pully timing mark doesn't line up by about 90 degrees. When we line it up, it feels like the valves are hitting the pistons (turning by hand). We are 99% sure we have the crank at TDC but even then, the slot in the flywheel is not in line with the blanking plug that you push a locking pin into.

My friend has tried lining the crank up by judging the valve position for No:4 cylinder, it's a bit beyond me at this stage. Anyway, when we turn the engine over, it "chuffs" up the snorkel and won't start.

I'm confused!

Tomorrow will be my 3rd day of lost earnings so any help will be much appreciated.

Daz

What are you lining the marks up with?

All lined up with the arrows on the back of the timing belt casing. For the crankshaft, we have lined up the woodruff keys, on the injector pulley there is a dot and also we took off the blanking plug on the side and pushed a drill bit in and it appeared to lock the shaft in the same position. As for the cambelt, although there is a dot on the pulley, it seems to be out.

Is it possible we've got TDC wrong? (my friend is sure it's correct as it did it from "feeling" with the valves and when we looked the woodfuff was bang on the arrow).

It's the camshaft not matching that I can't understand

Daz

SuperDaz said:

All lined up with the arrows on the back of the timing belt casing. For the crankshaft, we have lined up the woodruff keys, on the injector pulley there is a dot and also we took off the blanking plug on the side and pushed a drill bit in and it appeared to lock the shaft in the same position. As for the cambelt, although there is a dot on the pulley, it seems to be out.

Is it possible we've got TDC wrong? (my friend is sure it's correct as it did it from "feeling" with the valves and when we looked the woodfuff was bang on the arrow).

It's the camshaft not matching that I can't understand

Daz

Click to expand...

If I remember correctly, the cam shaft rotates twice for every single rotation of the crank shaft. Any resistance that you're feeling when turning the cam shaft could be one of two things:-

1) Resistance of the valve springs
2) Valve hitting piston

The problem you have with this engine, is accurately judging Top Dead Centre. You'd usually stick a length of wire in through the glow plug hole and then turn the engine over by hand until the wire is pushed back out of the hole to a point where the piston is at the top of the cylinder. Then, just before it reaches the point where the wire starts to drop back down into the engine you have TDC. Ofcourse, the 2.5N/A has pre-combustion chambers which prevent you from being able to accurately feed a wire into the cylinder in this way.

What I'd suggest in this case is to drain the oil from the engine and remove the sump. Then, remove all four glow plugs (to make turning the engine over a little easier) and lay directly under the engine and identify the big end cap on number one piston (ie. the piston at the very front of the engine nearest the radiator). Keep a torch set on the number one piston and then have your friend turn the engine over until you can see that the piston has reached the full extent of its travel in the cylinder. Immediately lock the crank shaft pully. You may have to back the crank shaft off or forward ever so slightly.

You have now established TDC on cylinder one and four.

You now need to set the cam shaft. In principle, at TDC you are either compressing gas or pushing gas out through the exhaust valve. I'm not sure whether it matters? Remove the rocker cover (undo the three nuts on studs or three bolts) and lift it off. The setup of this engine if you're looking at it from the passenger side is (E = exhaust, I = intake) E I I E E I I E. Rotate the crank shaft slowly anti-clockwise and look at valves one and two. Determine which valve is open before TDC. If both valves are closed the engine is on a compression / firing stroke. If the exhaust valve opens, the engine is on an exhaust stroke.

-Pos

I think yu will find cam-shafts rotate at half the crank, not double.

The Mad Hat Man said:

I think yu will find cam-shafts rotate at half the crank, not double.

Click to expand...

Ofcourse! Sorry

Sump off? to find TDC????????????? HOLD ON A SECOND HERE.

Finding TDC is simple, undo the plate on the back of the engine and find TDC by looking through the hole - there is a notch in the flywheel... when it is in the middle of the hole that's TDC...

discomania said:

Sump off? to find TDC????????????? HOLD ON A SECOND HERE.

Finding TDC is simple, undo the plate on the back of the engine and find TDC by looking through the hole - there is a notch in the flywheel... when it is in the middle of the hole that's TDC...

Click to expand...

Thanks for your reply's guys.

I thought that notch was for locking the flywheel via pushing a drill bit into the little "hole in a bolt" just above the plate? Which then seems to take it past TDC if you are using the crankshaft woodruff key as your guide

Daz

Right. Re-timed it again locking the flywheel with a pin. This has positioned the CRANKSHAFT 1 tooth past where we had it before. CAMSHAFT dot still doesn't line up so I have positioned it with the valves on no:4 cylinder one just closing and one just opening. Cranked it over and after 30 seconds it fired but died, tried again with same result. Tried bleeding fuel pump but no bleed screw on top of the pump

Tried priming it with the lift pump but having never used this before, it doesn't feel like it is doing anything (I tried turning engine over 90 degrees too)

This is so frustrating (I should be used to it I suppose)

Daz

its probabelly easyier changing it to 2ootdi and less trouble

Bought some easy start and amazingly it's now running. With Grey smoke and lots of it !!

Tried moving the fuel pump made no difference, moved pulley along another tooth, no difference. Aaaaaaaargh

your doing it wrong, this is an easy job when you know how!!

look on ALL THREE pulleys, you will see a little tiny dot stamped into them. Line these up with the arrows. thats it! The woodruff key method is WRONG for this engine.

Oh yeah, and also promise me that you will NEVER use Easy start again,

oh yeah, you will have to CAREFULLY force the camshaft past the pistons with a socket over the bolt on it.

You will also need some new pushrods, they are a couple of quid each.

p p s - you dont need to find TDC thats used for fine tuning the timing with a matching injection pump locking pin.

LOOK FOR THE DOTS!!

Boydy you are my hero! It's still smoking but not as much AND when I move the injector pump, it actually makes a difference now!! I can hopefully drive it now :cheer2:

Where were you 2 days ago :lol: