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Chain and Sprokets Replaced/Still Timing Issue

Thanks for all the input and feedback. Not distributor, weeding that one out, and even put a new cap and rotor on. Wondering what else it could be if it were ignition though? Will not stay running at all now.

The crank is hard to turn at some points, getting it to TDC, which is making me wonder if something else could be wrong, but that might just be the compression in the cylinders.

I have confirmed that I put the new top sprocket on at the exhaust stroke versus compression (when it is set at TDC with the harmonic balancer marks, and double checking that by pulling plug number 1 and the valve cover, watching the valve movement on 1, the distributor rotor has to be set 180 off from #1 plug wire to run the engine at all now).

There is also an obvious small leak around various edges of intake manifold gasket where it meets heads and engine block. Though may not be related.

So here is what I am going to do:

Take the front engine apart again and reset sprockets. Will remove valve covers again to watch the valve movement. But also thinking should go ahead and take the top part off as well (intake manifolds and heads), but I will check back here before I do that part. Any specific things I should be looking for in this process that haven't been mentioned yet? If sprocket is 180 off which I presume, that would make sense as to why it keeps going out. Or as someone else mentioned 1 tooth off, or both, 180 and 1 tooth off.
 

fatherdoug

Tonto Papadapolous
Thanks for all the input and feedback. Not distributor, weeding that one out, and even put a new cap and rotor on. Wondering what else it could be if it were ignition though? Will not stay running at all now.

The crank is hard to turn at some points, getting it to TDC, which is making me wonder if something else could be wrong, but that might just be the compression in the cylinders.

I have confirmed that I put the new top sprocket on at the exhaust stroke versus compression (when it is set at TDC with the harmonic balancer marks, and double checking that by pulling plug number 1 and the valve cover, watching the valve movement on 1, the distributor rotor has to be set 180 off from #1 plug wire to run the engine at all now).

There is also an obvious small leak around various edges of intake manifold gasket where it meets heads and engine block. Though may not be related.

So here is what I am going to do:

Take the front engine apart again and reset sprockets. Will remove valve covers again to watch the valve movement. But also thinking should go ahead and take the top part off as well (intake manifolds and heads), but I will check back here before I do that part. Any specific things I should be looking for in this process that haven't been mentioned yet? If sprocket is 180 off which I presume, that would make sense as to why it keeps going out. Or as someone else mentioned 1 tooth off, or both, 180 and 1 tooth off.

You are correct about the assumption. You will feel resistance at the top of the compression stroke. You are compressing air up against the head. That is normal.
 

Fellro

Moderator
Staff member
You really don't have to change the cam sprocket, as its relation to the crank is fine. What you need to do is set the crank to the timing mark, verifying that both valves are closed on #1, then pull the distributor out and rotate the rotor to point to the #1 cylinder. You will want it to be just a bit before when you drop it in so that once it seats, it is right on #1. The only relationship that is wrong is the distributor to cam relationship. The cam to crank timing is fine. If that was wrong, it would never run right.

Now, if you feel there is leakage at the manifold to head, that is an issue if it is a vacuum leak, and will make it run totally crappy, and will potentially vary with temperature.
 
Has the cam on the distributor shaft been greased with special grease?
I've seen ungreased cams wear out a points rubbing block in no time. The result of this is intermittent running.

Because these trucks get all sorts of swaps etc... i didn't want to assume the type of ignition. It was never mentioned what type.

This is one of those times...i was there to experience this myself rather than by internet.

Can you take videos and post to YouTube ?
 
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You really don't have to change the cam sprocket, as its relation to the crank is fine. What you need to do is set the crank to the timing mark, verifying that both valves are closed on #1, then pull the distributor out and rotate the rotor to point to the #1 cylinder. You will want it to be just a bit before when you drop it in so that once it seats, it is right on #1. The only relationship that is wrong is the distributor to cam relationship. The cam to crank timing is fine. If that was wrong, it would never run right.

Valves may be clogged or worse. Noticing more as taking apart. Front cover is off, sprockets still aligned, yet something seems off with valve push roads. Will know more when I get the heads off and can inspect the valves and pistons.

Now, if you feel there is leakage at the manifold to head, that is an issue if it is a vacuum leak, and will make it run totally crappy, and will potentially vary with temperature.

Intake manifold came off way too easy, so intake manifold vacuum leak is already one problem now. And there was previous variance in timing with temp change, after driving, and kept getting worse. (Got to get an aluminum intake manifold, that thing was heavy.. too heavy to even clean.)

Taking a break for the day, work on getting those heads off tomorrow.

0423151424.jpg
Might as well, got this far.....
 
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Fellro

Moderator
Staff member
The vacuum advance must be unhooked when you time, if not, you will see a variance in the timing indicated. Not sure if you were aware of that or not.
 
The vacuum advance must be unhooked when you time, if not, you will see a variance in the timing indicated. Not sure if you were aware of that or not.

Speaking of the vacuum advance... there was a vacuum check valve, original, between carb and distributor, even had markings on it for which side is for dist and which side for carb, but it made absolutely no sense. Vacuum is sucking into carb, the vacuum check valve that was on there (I took it off) would not allow suction, but if you suck on the advance from dist, the advance moves.

So why would there even need to be an check valve, and why would it be labeled to keep the vacuum from pulling in the direction it needs to for the dist vac advance?

But none of that made a difference either way during my various test before I pulled everything, but should know how the advance should be hooked up the right way before I put everything back together. I even pulled the hose and plugged in during times it was idling right, and it made no difference in anything, but the advance was working (by sucking on it to see if the internal parts moved)
 
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Fellro

Moderator
Staff member
At idle, you don't want/need much advance, it is more for when you hit the gas. You should see higher vacuum when revving, which then advances the internals. The mechanical flyweights will do the advance as the engine speed increases.

As to the check valve, the only reason I know of is to keep it from advancing when cold, but if it had no temperature sensing capabilities, then I am not sure why it would be there to prevent advance. Generally, the advance either goes straight to the carb, or through a temp switch on the thermostat housing or just behind it.
 
As to the check valve, the only reason I know of is to keep it from advancing when cold, but if it had no temperature sensing capabilities, then I am not sure why it would be there to prevent advance. Generally, the advance either goes straight to the carb, or through a temp switch on the thermostat housing or just behind it.

:suspicious: Ok, so, there is the temp valve, or switch, with 2 ports, and I replaced it recently, but was not hooked up that way (so was hooked up wrong). So vacuum hose connection should be as follows then:

distributor - temp switch/port - carb

correct?

And, :wavey: I figured out other issues now that heads are off (post picks later.

So not only was the intake manifold gasket shot to hell, but also both head gaskets, or there was no head gaskets. The only thing between the heads was the metal gasket but I thought that there was suppose to be a regular gasket on either side of the metal one? :suspicious: And both heads lifted right off... :suspicious:

As far as timing chain and sprockets? As I put them on, and they were set correctly, and on the compression stroke. :)

My only concern with the new timing chain is that it is a little loose, and should not be. Why is a new chain I put on three weeks ago loose?
 
:suspicious: Ok, so, there is the temp valve, or switch, with 2 ports, and I replaced it recently, but was not hooked up that way (so was hooked up wrong). So vacuum hose connection should be as follows then:

distributor - temp switch/port - carb

correct?

And, :wavey: I figured out other issues now that heads are off (post picks later.

So not only was the intake manifold gasket shot to hell, but also both head gaskets, or there was no head gaskets. The only thing between the heads was the metal gasket but I thought that there was suppose to be a regular gasket on either side of the metal one? :suspicious: And both heads lifted right off... :suspicious:

As far as timing chain and sprockets? As I put them on, and they were set correctly, and on the compression stroke. :)

The head gasket is mainly a crushable metal with a special emphasis around the cylinder holes.
No other gasket for heads.

Can you not take photos and post them here?
 

Fellro

Moderator
Staff member
Factory head gaskets are generally just a thin stamped metal piece. The replacements commonly are a combination of metal ring and backer with a plastic type material. Look for any black carbon between the cylinders across the wall between them. That will help show if the gaskets had failed or not. If so, it is a good idea to also get the heads flat checked.
 
I don't know which engine you have so I'll guess a 360.

These vacuum diagrams may help you.

http://s69.photobucket.com/user/mil1ion/library/73-79 Ford Truck Information/Emissions Related/360

Yep 360, but now with edelbrock carb so will be different slightly. But thanks! :)

And here is pics from the project so far.... Have lots of cleaning to do next, and get a bunch of gaskets. :)

0424151754.jpg

0424151755.jpg

0424151752.jpg

Oh, and an edit... The exhaust manifold(s) in one of those pics, those are new (or reman), I got them last September, but couldn't get the old ones off. So now I can finally put them on. Excited about that...
 
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Fellro

Moderator
Staff member
Not seeing anything obvious yet...
 
Factory head gaskets are generally just a thin stamped metal piece. The replacements commonly are a combination of metal ring and backer with a plastic type material. Look for any black carbon between the cylinders across the wall between them. That will help show if the gaskets had failed or not. If so, it is a good idea to also get the heads flat checked.

There was some of that black carbon there, yes. I just did an initial clean before those pics. And I don't trust just a metal head gaskets, doesn't make sense since that is a serious engine component... but perhaps there is some logic to it.

So some strategic tips on putting this all back in the best way possible when that time comes? Still will be awhile though. I want to take the valves out and soak them, and replace anything that seems worn or broken. Would like to get the heads and intake manifold super cleaned. Steamed cleaned by a shop? Or any other options (without buying tons of chemicals...).
 

Fellro

Moderator
Staff member
A machine shop will hot tank them. Since you have them off, you would be ahead to have them checked over by a shop to see how good they are and what work they need. If the seats have not been done, you may need to have hardened seats installed. That will run a bit, but if you have the old leaded seats, you will wear them out quickly and have to do this all over again.
 
Valves:
Valve seats and valve seals are also suspicious. While trying to compressed a valve, a seal inside started cracking in pieces and coming out.

Timing Chain:
More concerning before I get to all that, is what I mentioned about the new timing chain being a little loose, even when turning the crank, it is not getting tight on one side. Is the normal? I wouldn't think not, but why would it be loose when just put on three weeks ago? But it is where I left it, at TDC and on compression stroke, so not 180 off.

Pistons:
As far as pistons and cylinders goes, all seems good. No weird sounds, no scratches in cylinders, and I cleaned carbon off top of piston heads as well. And crank turns smooth, smoother than with heads on, which makes me think sticky valves or something going on with valves.

That is my update so far. This will be a slow project...
 

Fellro

Moderator
Staff member
Timing chain should only be tight on one side, it will loosen a bit as it stretches. You will never find a chain maintain total tightness, nor do you really want it to without a tensioner. It would put too much strain on the front of the cam and wear out the front bearing.
 
Thats what I was thinking,but my ? would be about the lifters,are they
solid or hydralic,if they are hydraulic,are they good?
I dont know everything about engines,but I know that if theres a bad lifter,
or a flat lobe on a cam,it could create a problem that some people might think
its in the timing.which could have been the problem all along..:)
 

Fellro

Moderator
Staff member
A tick will accompany such issues as well. When you have a collapsed lifter, it is quite audible, as are cam lobe issues.
 

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