Timing chain question.

[Gregs672000]

New engine, no carbon. Less than 10 miles. It can happen.

I see! Dumpin some fuel in there!

[Gregs672000]

What's lying against that front head stud in your picture? Is it some sort of washer...

I think it's a reflection.

[newby]

Ok, let's see if I can do this...

Pull the plugs. Note their color (report back). Should be NGK BPR6, BPR6ES, or equivalent. Gap around .44 I believe

Remove the valve cover.

Rotate the motor to 17 degrees timing on the crank, between the next to last and last timing mark, zero being at the far left and 20 the final rightmost mark. Look at the cam lobes, and if both lobes are up on number one, your good. If not, rotate around again until they are and timing is set at 17 again.

Remove the distributor cap and make sure the rotor is pointing at number one plug wire. Since you have an EI distributor, I THINK you can look at the four prong rectifier that rotates around with the rotor and it should line up with its opposit prong on the outside ring. (If others know please confirm. I believe these work just like a set of points and trigger the module that then fires the plug via the coil). If it does not line up, then I would loosen the distributor and rotate it slightly until it does. If so, the motor is now static timed to 17 degrees BTDC. We will do the final adjustment with the timing light.

You have already adjusted valves so we are good there. If you have questions just ask!

1. Plugs pulled they are the right kind (BPR6ES) I don't have a gaping tool at the moment. They are black with soot and I Just put them in.
2. I have static timed the engine pics follow.
3. valves have been adjusted and checked twice. left them at 8 n 12

[newby]

It is real easy to check the valve timing. Place crank to TDC on compression stroke. Make sure you turn the engine the in its normal direction. Place a straight edge across the top of the head. The two bolts should be parallel to the head. Dowel pin at 12 o clock.

I think I may know you pinging problem. Are you running a stock exhaust manifold.
Arnold

I have the ceramic headers that i got from Dean
But here is a picture of my cam gear with the crank pulley set to the TDC mark. The two bolts are not parallel and my dowel is more like at the 1230 mark. Am I a tooth off?

Of course the pictures posted upside-down!

[Nissanman]

Seems to be a little advanced to me.
Timing mark/indent should be at 3 o'clock with everything else as it should be

[Gregs672000]

I would say yes, yes yes.

You all agree?

I hope we haven't bent a valve or two here my friend...

[newby]

The question now is. How do I fix it? I'm thinking I'll mark the chain now and then unbolt it, and carefully move it back. But is it one tooth or two? How do I slacken the chain? Do I have to remove the tensioner also? I don't have a new gasket or fixing plates so if i do have to remove everything I need to source some parts from the InterWebs. Thanks for all your help so far Greg. BTW my name is Fernando, since you asked me and I rudely forgot to answer.

[SLOroadster]

Seems to be a little advanced to me.
Timing mark/indent should be at 3 o'clock with everything else as it should be

The cam is looking advanced because the crank is advanced. It should be a TDC, and that pic clearly shows that its not. Pull the motor through till the big notch in the pulley aligns with the timing mark and double check it. I bet its fine. It does have the evil L however.


Will

[newby]

Seems to be a little advanced to me.
Timing mark/indent should be at 3 o'clock with everything else as it should be

The cam is looking advanced because the crank is advanced. It should be a TDC, and that pic clearly shows that its not. Pull the motor through till the big notch in the pulley aligns with the timing mark and double check it. I bet its fine. It does have the evil L however.


Will

It's at TDC now. And the cam gear is past three o clock. That picture was to illustrate wether or not I static timed it correctly. I used a little white out on it. When the crank was at that position the cam gear was at 3 o clock I advanced it to TDC and noticed that the cam gear moved so I took a picture of it to ask the question of it being a tooth off or not. Sorry for the confusion

[jamesw]

OK - thanks for clearing that up. If the marks line up and your cam gear looks like it does in the picture, then your cam timing is off.

It is easy to fix howerver. In a nutshell what you'll want to do is get the chain off the cam gear, and turn the cam and gear until they are in the right position, then "put the chain back."

How you actually do that is put a zip-tie or wire to hold the chain, then unbolt the cam gear. Then you actually take the gear out of the chain and put it back in - in the correct position. Of course it won't bolt onto the cam anymore so you'll have to rotate the cam until they line up again. That's harder than it sounds since the cam will push on the rockers which will push on the valve springs. To make life easier you can either loosen up some of the rockers all the way and pop them out, or loosen the cam tower caps and actually take the cam out and turn it.

In either case - you can fix this in an hour.

HTH
James

[Datsun 440]

You are tuning the crank clockwise to come to TDC If not the cam could be out that much with the lash in the chain. If you are cam is out a tooth or two.
Arnold

[Gregs672000]

Agree with all, but I do believe he will find the cam off for sure. We won't know if he bent a valve or two until we get it set right and do a compression or leak down test. If the valves are bent, I am sorry... So sorry... But the head will have to come off and the valves replaced, and maybe the seats touched a bit to make sure they seal properly. We will cross that bridge when we get there.

The tensioner will want to kick out. You might try lightly zip tying it, or just be aware as it will tension the chain and make it harder to put the sprocket back on. I'm always paranoid, so I stuff a small rag down the front just to make sure that if a washer or bolt drops it doesn't go into the engine.

Hard to tell how many teeth. Do what seems to make sense, bolt it up, rotate it around by hand and take a look again. See 440's post and pic on what it should look like. Do this with the plugs out, much easier to turn as you probably know.

[SLOroadster]

Looking at the pic of the cam, I'd wager its 1 tooth too advanced. You might be able to see if there has been contact with the pistons by rotating the engine through and looking through the spark plug hole at the tops of the pistons. If you see a crescent shaped mark on the top of any of the pistons, there was contact and most likely nothing good has come from it.

I'll post a couple pics of how things should look in a bit, I can't access the pics from this computer.

Will

[SLOroadster]

Here is a shot of a shimmed tensioner.

and another showing a small amount of space between the tensioner and the shims.
You can just see the timing mark is a little before 3 o'clock, however I have an adjustable timing gear and the cam was advanced some. I was marking things in hopes of getting them back to where they were when I put the motor back together. This would have been at TDC.


I thought I had another couple shots showing the timing marks where they should be.

Will

[Gregs672000]

Looking at the pic of the cam, I'd wager its 1 tooth too advanced. You might be able to see if there has been contact with the pistons by rotating the engine through and looking through the spark plug hole at the tops of the pistons. If you see a crescent shaped mark on the top of any of the pistons, there was contact and most likely nothing good has come from it.

I'll post a couple pics of how things should look in a bit, I can't access the pics from this computer.

Will

Good idea before pulling the head for sure.