Setting up the Timing Belt & Distributor

[DOCTORBILL]

This is a separate thread from my other Thread on the Head and Rings.

I am now wondering if I set up the Timing Belt properly.
I followed the Chilton Manual's method.

I cut a hole in the Timing Belt Cover over where the Camshaft Gear Mark (CGM)
would be at the top - so that I can see the damned mark!


When I re-assembled the Head etc., I turned the main shaft to where the
Pin or tab was vertical (UP - 360 or zero degrees). I don't know
the mechanical jargon.


As shown here, the crankshaft pin is about 20 degrees clockwise while the timing
mark is vertical.

Does vertical mean straight up or at the slant of the engine which is about
10 degrees to the right...?

The Fan Pulley timing mark is not up at that point! It is at about 340 degrees!

Anyway, after putting the Head back on, I turned the Camshaft Gear (CG) to
line up with that mark on the flang behind it.

Then I put on the Timing Belt. You have to turn the CG until the CGM is about
10 degrees past it because when tightening the Timing Belt, the CGM goes
backwards about 10 degrees!

Did I do wrong by doing that? They wouldn't both be on the mark with the
Timing Belt cinched tight otherwise.

Now - after putting the Timing Belt Cover (TBC) back on, and running the
engine, I cannot see the timing mark on the CG when the Main Fan Pulley
mark is vertical or even on the timing mark.

This disturbs me.... the engine runs! Won't idle...

For every three turns of the Crankshaft, the Camshaft turns one time - yes?

So I wouldn't necessarily have the CGM at the top when the Crankshaft mark is TDC...right?

I am concerned that maybe I screwed this up...!

DoctorBill

[Crvett69]

crankshaft turns twice for every turn of the cam. to make sure it lines up right the bottom pulley should be at 0 on the timing mark and the mark on the cam gear should be straight up and in line with the notch behind it on plate behind the cover. if not you need to take cover off and retime it. to do that first loosen the 2 idler/tensioner bolts, swing it till its where belt is loosest and tighten one of the bolts. take belt off, top gear (cam) has a line that should line up with mark in metal shield behind it, should be straight up and dowl pin in cam should be straight down. for lower gear there is a dot or triangle on front of it, that should line up with a line on oil pump housing behind it. will also be straight up. when you put belt on try and keep the side without the tensioners tight as possible then put tensioner side on, then loosen the tensioner bolt and rotate the crank 2 turns clockwise until top mark lines up again. do not let the engine turn back the other direction while turning it. this will tension the belt and you can make sure the marks on the cam and crank still line up, if they do, tighten the 2 tenioner bolts and put cover back on

[DOCTORBILL]

Alright - I did what you described when I put the Head back on.. I made sure
that Piston #1 was TDC also.

I guess the test is that I pull out the plugs and rotate the Main Fan pulley by
hand until the timing mark is TDC.

Then the Camshaft Pulley Mark (CGM) should be dead on its mark.

If not - rotate the main pully once more - then the CGM should be on its mark.

If not - then take it all down and try assembling it again. Lord!

Without the hole I had cut, how the Hell could you test this!?
You'd have to do this BEFORE putting the Timing Belt Cover on.
If the Timing Belt ever jumped a sprocket, you couldn't see it.

I pulled the plugs again - they were black and sootie already (they are new)
after only maybe 10 minutes total running since I put the Head back on.

I do good work...those marks are "dead on" - Timing Mark on "0" and
Cam Gear Mark lined up exactly!

And the Distributor Rotor is Vertical and the contact sweep arm is on top.
I loosened the hold-down bolts and rotated it a smidgen counter-clockwise (5°) as I
faced the Rotor. That would be Before TDC, I believe...

Seemed to run a tad better, but still dies off and won't idle.
The TPS voltages are next - tomorrow.

What's next!?

DoctorBill

PS - With three cylinders, it is two to one (2:1) turns? You sure about that?

[Crvett69]

yes i am sure, crank turns twice to one turn of crank, doesn't matter how many cylinders it has, would have to turn 8 times to one turn of the cam for a V8 if that was the case. its a 4 cycle engine. piston at top, intake valve opens, draws in air/fuel, piston reaches bottom, valve closes, piston comes up and creates compression, spark creates explosion and drives piston down. piston reaches bottom of stroke, exhaust valve opens, piston moves up forcing spent mixture out of exhaust valve. piston reaches top and cycle starts over, as you see the piston went up and down twice and each valve only opened once

[99Metro]

If it was me, I'd take the timing cover off, and take the crank pulley off. Remove timing belt. Then make sure the alignment mark on the crank sprocket is aligned so that it points centerline up to the cam pulley. There should be an indent on the face of the crank sprocket. The cam sprocket alignment mark needs to point up also right at the valve cover mark. Then put the timing belt back on and doublecheck alignment marks. Then put it all back together. It is worth spending the extra time to MAKE SURE the timing marks are aligned correctly this way. With everything in the way you could be a couple teeth off and not know it.

just my 2 cents [cut and paste disclaimer here]

[DOCTORBILL]

When the Timing Mark on the Fan Pulley is at exactly Zero, the CamShaft Gear
Mark is exactly over the Mark on the Flange behind it.

So it has to be OK....

See my other thread - I'm taking the Fuel Tank out to change the Fuel Pump.

DoctorBill