New cam chain seems to slap when turned by hand

[stangsteeda]

That is some good troubleshooting tips on the compression test. I will perform that before I tear it back apart.

From what I remember when I compared the old to new guides they looked identical.

And when I took the motor apart nothing was broken or excessively worn which makes me wish I had of kept driving. The only thing I found odd was that the rear chain had a little slack in it similar to the original problem at the top of this thread, but... the motor may have not been at TDC when disassembled or I thought maybe the tensioner was in since it had not had oil pressure in it for about a week.

The new jackshaft plug I installed had a metal side I put to the inside and the outside was completely covered in rubber not just a rubber center plug. I was pretty careful not to drive it in too far since I was actually worried about that when I was installing it.

 

[2000StreetRod]

Other noise source?

I'm hesitant to mention this but since you found nothing wrong with your timing chain related components maybe the source of the noise was (and still is) something else. It is difficult for a mechanic to accurately diagnose timing chain problems without pulling the valve covers and inspecting. Perhaps the "something else" is still there and deteriorating to increase the noise you're hearing. Have you checked the welds on the cat shields? They are prone to break which results in a vibration induced rattle. Have you removed the serpentine belt and run the engine for less than a minute to see if it's coming from the water pump, steering pump, idler pulley, belt tensioner or A/C compressor clutch? Could the starter be hung up and contacting the flex plate ring gear? I would eliminate all of these potential noise sources before pulling the engine.

 

[McSlug]

I replaced my front timing components and noticed the same slack in my crank to jackshaft chain. What I did was turn the jackshaft backwards just enough to taught the chain on the traction side and bringing the slack to the slack side. Then I held a bar through one of the holes in the jackshaft sprocket to stop it from turning as I tightened the jackshaft bolt. This kept the slack on the slack side leaving the tensioner to pick it up.

As far as the sound goes I hope you can make sense of this.

I have heard 3 explorers with the broken front cassette and they all sound the same. Its very much like a diesel engine, the sound is a bit hollow, changes pitch,and has a recurring pattern to it. You can pretty much hear the guide move side to side with the rotating of the chain. Revving the engine has more influence on this sound and there's a vibration when dropping the revs quickly.

When the crank to jackshaft tensioner goes it's loud, fast and constant. Sort of like over revving an engine with a big end bearing problem. This is the chain striking the posts of the tensioner housing. Revving the engine has less influence and the pitch doesn't change.
I have read here that the rear chain can produce the same noise. As the chain strikes the mounting post for the tensioner at the valve cover.

Also before you start the engine after putting it together disconnect the coil pack and pull the fuel pump fuse,crank it untill the oil pressure switch goes on then start it.

 

[stangsteeda]

So guys I tried to get the compression tested today but I didnt get a chance finish since I had to fix a broken clutch cable on my mustang so I would have a vehicle to drive. But.... I was reading another thread that I think told me my problem. And in response to the questions about the cat heat shiels and running it without the belt I did check for both of those things before I took it down.

Is it true that when the right (passenger side) cam is at TDC the slot in the cam gear is parallel to the head surface and the OFFSET WOULD BE ABOVE THE CENTER LINE OF THE CAM?????. Is that the position that would put both valves of cylinder #1 in the closed position. If so I am pretty sure that cam is 180 degrees out.

My next questions,

1) I have read before the motor will run but very poorly in this scenario, is that true?

2) If this is the what has happened, is there a possiblity I have avoided piston to valve contact and not killed the motor?

So tomorrow I should have some time to confirm these results with the compression test and maybe start pulling off the intake and valve covers to see if this is what I screwed up.

If it looks like the motor is unharmed and I can just retime it and throw it back together I will get all the slack out of the traction side of the chains before I torque the lock down the cam gear to torque it.

 

[BobWiersema]

Is it true that when the right (passenger side) cam is at TDC the slot in the cam gear is parallel to the head surface and the OFFSET WOULD BE ABOVE THE CENTER LINE OF THE CAM?????.

No:

With the engine at TDC both camshaft timing slots are below centerline of camshaft.

I thought you said you use the timing tool kit, I dont think you can get it wrong with that.

 

[2000StreetRod]

Ford timing instructions

The original Ford instructions for timing the camshafts could be misinterpreted to read rotate the crankshaft 360 degrees between timing the right bank camshaft and the left bank camshaft. If that is done the timing tools will fit with the camshafts 180 degrees off. The instructions were rewritten but still do not clearly state not to rotate the crankshaft. At least one member timed his camshafts 180 degrees out with the tool set last year. I don't know (and Ford doesn't state) if valve damage occurs. If your engine is timed incorrectly it is possible that you are hearing "interference". Do you remember rotating the crank between timing the camshafts?

 

[BobWiersema]

Now that I take a closer look at the tools, I think it is possible.

I dont see anything that would stop you from sliding that in upside-down.
Bad tool design. Unless that thing is stamped This Side UP. Judging by the key offset we are looking at the bottom in that picture.

Bob

 

[stangsteeda]

Well I tried to finish compression testing the motor but I dont know if my spark plug adapter oring is leaking on the test kit or what but I didnt get any compression that held on either bank. It would go up to 170 - 180 while turning over but immediately leak down to zero.

So I continued to remove the valve covers and intake. Put the crank at TDC, the drivers side cam is at tdc with the cam position sensor nub pointing up. The passenger side cam was not 180 out so I did actually set it right. But it was off by about 70 or 80 degrees. Both cam chains are good and tight on the traction side now. So I am assuming what happened is the slack I had (mentioned in first post) got taken out at the expense of the cam rotating away from time. I am also assuming the noise I heard was chain slack at first followed by valve contact.

At this point I cant justify any more time in diagnosis and work on a motor with 140,000 miles and an unknown status of bent valves. In the same time of trying to figure out if valves are bent I could have already swapped a motor for an 02 or newer with many less miles. I need this thing back on the road to pull the jetskis, so I have run out of time and going to just throw the towel in on this SOHC and get another.

Thanks for all the help guys.

 

[2000StreetRod]

What a shame!

When the #1 piston is at TDC on the compression stroke and the right camshaft retaining sprocket bolt or jackshaft rear sprocket retaining bolt is loosened the camshaft will jump either 50 degrees advanced or retarded due to the valve spring pressure. The special tool that engages the slot keeps the camshaft in position. The right camshaft sprocket retaining bolt tightens counter-clockwise (toward the jackshaft) which tends to slacken the chain on the traction side. The special tool keeps the sprocket from rotating when tightening the bolt. The special tensioner keeps the chain taught.

Even if you forgot to use the special tensioner there is not enough piston movement in the hydraulic tensioner to allow 50 degrees of camshaft movement. If all of the special tools were correctly installed (including the crankshaft holder) when you tightened the camshaft sprocket retaining bolt then I suspect you did not torque it tight enough. The camshaft probably slipped to its 50 degree out position after you removed the tools. The design is such that when the engine runs the retaining bolts will tighten on the camshaft sprocket and jackshaft sprocket. That could account for the additional degrees in timing error.

At this point having run the engine with the right cam 70 degrees off I agree that you have possibly sustained valve damage on the right bank and the noise you are hearing could be the valves. However, since you have found the source of the problem (70 degrees off) and have all of the tools to retime I suggest that you do so. Even if you end up replacing the engine, it would be nice to be able to tell the recipient of the old engine if the valves are damaged. The bearings and rings on the SOHC V6 can easily last 250,000 miles.