does this 360 t chain look too loose?

[valiant1966]

I pointed out what I could see. The other portion of the pic is so dark, it would be a guess as to what was going on there.



I did see your other pic with the straight edge and as I said before, your chain is fine. Some of the folks are here for the giggles, not to help. Dennis

 

[krazykuda]

Did anyone see the strait edge version picture? 3/16 & 1/4" when pushed away from strait edge.

Is this alright? Parts are new and cam as stated is degreed. Is 3/16 to 1/4" acceptable?

According to the procedure and picture that I posted, that is ok. You have max of 1/2" when measured that way.

 

[mini]

Ok chuckles. Sure, I posted too quickly. Why point out the slack closest to the gear. Max slack is mid point....anyways.

Did anyone see the strait edge version picture? 3/16 & 1/4" when pushed away from strait edge.

Is this alright? Parts are new and cam as stated is degreed. Is 3/16 to 1/4" acceptable?

This wasnt for you, this was to correct valiant. And to get clarity from your picture. No giggles here mate.

 

[Rapid Robert]

With a 1&1/4" socket/short extension/breaker bar on the crank I would get the dampener slit on TDC then hand bump it CCW till the slit is at say 10 or 15 BTDC then with a helper eyeballing a pushrod that is on a ramp (moving) I would carefully hand bump the crank back CW & have him holler the EXACT instant the pushrod moves & you note how many degrees the crank moved which is how many degrees of cam phasing change that amt chain slop is going to cause you

 

[Cudafever]

With a 1&1/4" socket/short extension/breaker bar on the crank I would get the dampener slit on TDC then hand bump it CCW till the slit is at say 10 or 15 BTDC then with a helper eyeballing a pushrod that is on a ramp (moving) I would carefully hand bump the crank back CW & have him holler the EXACT instant the pushrod moves & you note how many degrees the crank moved which is how many degrees of cam phasing change that amt chain slop is going to cause you

Yes this^^^^^^^it is some thing that i do with a used eng, but its a good way to decide if it is bad, good or..... just OK

 

[nm9stheham]

"Is this alright? Parts are new and cam as stated is degreed. Is 3/16 to 1/4"acceptable?"

I believe the procedure illustrated is for checking a 'used' chain to what are called 'service limits', which is the loosest a chain can be before requiring replacement. Factory service limits are preeeetty loose and I personally would not even think of starting there with new parts. You gonna have plenty of potential for timing slop if this stays in.... your loping cam may be a 'flopping' cam! Good that you asked.

When the cam was timed, did they put in a cam button to set the cam timing? Do you know the value perchance?

(And, despite the snide comment above, most are trying to help; that comment is not necessary, and only reflects a single opinion.)

 

[360moparjunkie]

With a 1&1/4" socket/short extension/breaker bar on the crank I would get the dampener slit on TDC then hand bump it CCW till the slit is at say 10 or 15 BTDC then with a helper eyeballing a pushrod that is on a ramp (moving) I would carefully hand bump the crank back CW & have him holler the EXACT instant the pushrod moves & you note how many degrees the crank moved which is how many degrees of cam phasing change that amt chain slop is going to cause you

This sounds like a great idea. I will attempt this, but before I set the front cover. My idea is to print copy a zeroxed degree wheel to know this value before I button it up. Thanks for the input. I wish I knew the max acceptable cam phasing change in degrees.

 

[hacksaw]

Ya ... just a bit ..... ya can put the timeing cover on it and see in the crank is still in the center of the seal. If not a new under size line bore chain will only fix the one bad thing that is going to give ya head pains. Next will be the oil leaks from the rear main and T/C seals. Stock pistons and cam will be ok but is ya went to a zero deck and or a big cam ya will need to clay it to check for valve clearnce. Not tryin to freak ya out but iv been there dun that. In the end cost me a bunch of cash and still had to trash the block and start over. ...... If your not happy take it back or atleast make a call

 

[Bulldozer]

I would run this all day for the next 50,000 miles

 

[360moparjunkie]

"Is this alright? Parts are new and cam as stated is degreed. Is 3/16 to 1/4"acceptable?"

I believe the procedure illustrated is for checking a 'used' chain to what are called 'service limits', which is the loosest a chain can be before requiring replacement. Factory service limits are preeeetty loose and I personally would not even think of starting there with new parts. You gonna have plenty of potential for timing slop if this stays in.... your loping cam may be a 'flopping' cam! Good that you asked.

When the cam was timed, did they put in a cam button to set the cam timing? Do you know the value perchance?

(And, despite the snide comment above, most are trying to help; that comment is not necessary, and only reflects a single opinion.)

Im not sure...how would I tell if they installed a cam button?
I know I provided cam card and requested cam installed 2* advanced.
Not liking the sound of a floppy cam wandering back and forth.
I am estimating movement at about 1* +/- before I check it. I had some trouble w local shop finding a tensioner for me. Im considering summit or jeggs if movement proves excessive.
Thnx for input.

 

[nm9stheham]

Well you are looking at the right thing IMO: the actual degrees of movement of the crank vs cam.

Do the following if you would not mind; this is a better test than the slack test. (I am assuming that the timing cover is off so that you don't have the timing indicator by the damper to use of timing measurements.)
1) With the crank held so it is not moving, move the cam gear back and forth to the limits of the chain slack and carefully measure how far a link moves on the top of the cam. Use the center of a chain link pin as the measurement point. Measure this down to the 1/32nd of an inch if you can please. Do you have a finer scale to use? Or a dial caliper? That would be quite helpful for accuracy.
2) Then measure the diameter across the cam gear from one chain link on the right to the opposite chain link on the left.

Provide those numbers and we can calculate the number of cam degrees of movement and then then crank degrees and everyone can say if they feel that is a good or bad number.

As for the cam button, well the setup pix above sure do look right for degreeing the cam. You'll probably have to take off the cam bolt and pump eccentric and look to see if there is a small 'button' in an enlarged hole in the cam gear on the cam's dowel pin with an osset centering hole. Alternately, an offset key on the crank for the crank gear might be used; I am not sure what is most common on these engines. It would be good to check this out IMO.

 

[moper]

The V8s never used them - it was for the V6s originally because of the different number of valve events in the same 720° cycle. If you go to the dealer and ask for a timing chain tensioner for a 3.9L V6 & they'll be able to find and order it. It's also available from the aftermarket like Sealed Power, TRW, etc. Auto Zone's site has them too. I usually get mine from mancini racing or summit.