Hi All,
I took on a fairly involved (for me) repair as I dug in my 71 LT to replace what was an original nylon cam gear.
I went with Cloyes double roller and all went pretty well. I was 50:50 on whether it would fire upon reassembly.
Car fired right up and didn't seem to miss a beat! My home is about 4 miles from my buddies lift where the work was done.
Upon getting home I noticed a "rattle" that seemed to come from behind the timing cover, yeah!

I let the car sit and then also noticed a leak from the front of the oil pan. Turns out the timing cover lip
is splayed out on the bottom where it sits in the oil pan and leaking. (I used the one piece Felpro gasket that looks dry everywhere else)
I fired the car up again and all seemed fine but as the car warmed up, about 90 seconds or so, the "rattle" returned.
I put the car on 4 x jack stands I got under the car and sounds seems to emanate from behind the water pump, timing cover.

Since I have to replace the timing cover to account for the leak, what else should I look at? All I can think of are the
cam gear bolts. I used lock tight but not bolt keepers. I will go with the bolt lock plate this time as well.

PS, with the one piece gasket any chance I can get the timing cover off without having to remove pan and drain my brand new
high zinc motor oil from the pan?

 

Some double-row timing sets are so wide they require grinding face of block for clearance; other sets do not.
May be source of noise here; maybe not.
A good quality single-row set is all most need.

Did the old Nylon-clad cam sprocket show typical signs of cracking-breaking apart ? If so, those Nylon bits went into pan and/or oil pump screen.
If so, did you clean all of it out ?

 

Interestingly enough, the Cloyes setup is a fair bit "smaller than the standard set up as the original parts would not fit in the blow molded Cloyes packaging. They were too big.
I can't speak to front to back differences.
If it was rubbing I'd expect a different sound than a "rattle". When I get in there I'll look for witness marks though.
The original gear was in perfect shape. Doh!

 

Since old set may seem larger than new, perhaps new set is Cloyes 3023 ?

It's apparent your old Nylon-cladding is fully-intact and has less discoloration than most; it seems in good shape.

Did you torque new set's three cam bolts to spec ? Did you apply any thread locker to those bolts ?

 

The old set didn't "seem" larger, it is larger at least in total diameter.

Actually got a deal on a Cloyes 9-1100SP. Haven't been able to nail down any spec differences between that and the 3023.
I did thread lock (though hard to clean the gear threads in situ) and torque the cam gear bolts but I'm going back in to check anyway and may try a different Cloyes.

 

Your pic above is misleading because the when installed the gears do not mesh. I think if you stretch out the chain you'll find your old set fits the package... Or do you mean the gears themselves are larger diameter?

I've put the Cloyes 9-1110 street roller sets (same overall but for BB) in both of my recent builds with no problems of increased width and timing cover rubbing.

 

Yeah, not the best pic but the factory gears, even all tightly wrapped will not fit in the Cloyes packaging, (the cam gear+chain definitely a bit wider than the Cloyes) hence what you see. I'm assuming my rattle is some type of installation "error". Will know when I get into it again. Did you notice any noise difference when you went to the Cloyes?

 

Both of my engines had their original nylon gears, in very poor condition when I put in the Cloyes. I didn't notice anything different afterwards as to timing chain noise.

 

As for any needed clearancing, it's typically the front-to-back that becomes an issue; the side plates of chain may contact block face.

Please recognize I'm not there to either hear or see what OP experiences. I'm speculating based on what OP provides us and my hands-on experience elsewhere.
if, IF New set was so wide as to Require clearancing face of block, But if any needed clearancing was Not performed, that may also prevent cam sprocket from firmly seating onto cam snout. And, that scenario would prevent proper tightening of one or more cam bolts; thereby leaving them free to loosen, wobble and make some sort of unexpected noise (call it what ya will). I'm not proclaiming the forgoing is the root cause; I'm simply offering it as a credible suggestion. The preceding is presented as a possibility. I'm simply troubleshooting from afar; and Not finger-pointing.

W/ that said; heck, damper may be giving up the ghost ? In failure mode, they're often "noisy".

JMO: when all is prepped & installed properly and with thread locker; then cam bolt lock plate becomes belt-and-suspenders.
FWIW: the General used neither thread locker or washers; only cam bolt torque about 22-30 lb ft.

 

fstntq,

Don't overthink the product packaging fitments. That's immaterial. Either the new set fits without slack or it doesn't.

Just curious. What type of harmonic balancer "puller" did you use?
The type that grabs the three pulley bolts holes?
Or the jaw type that grabs that the outer ring of the balancer?

Are the fan belt pullies running true?

 

Hey, no throwing stones here, Spitballing is what I asked for and all I can do until I get in there again over the weekend
The original is wider than the Cloys so no side to side issues. The rattle start after a minute or 2 and may be coincidental but sounds like behind the timing cover. On disassembly to far, Balancer, WP all belts pulleys/fan etc. all parts seem fine..

 

Install fit was spot on and car fired right up.


I used a Napa rental puller which used the balancer pulley mount holes to pull the balancer, it worked great. I had to borrow their install kit for reinstall as the reinstall tool is not in the removal kit! I used a 3 jaw puller for the crank gear. Belt pulleys seem fine and would not cause the "metallic rattle" I heard. I could not tell if it was RPM specific as much above idle car is a bit too noisy to isolate out the rattle.

 

good on you for using proper pull & install tools.

 

I can't see the crank gear alignment dot. This timing set allows several advance/ retard setups. The cam shows "advanced" if the dots are lined up in the picture?

 

fstntq,

Going back to your original question.

You can remove & reinstall the timing cover with the oil pan in place*.
* It's not the best approach. May be frowned upon by some. But some have done it and it worked out ok.
As you said, the inner lip of the cover will fight you.
Some people have actually cut the inner lip off. Meh . . .
Some people loosen the front 6 bolts of the pan and gently pry down.
Some drain the oil and buy a new pan gasket.

Reviewing your issue of the rattle I would like to review your procedure just to make sure we are all on the same page.

Basically, all you did was replace the cam sprocket / crank sprocket with new Cloyes.
You rotated the crank first, so both cam timing dots lined up before you removed the old set. (easier)
The cam was never turned. The fuel pump pushrod was never involved.
The cam sprocket "bolts" were torqued down after installation, so the chain held the sprocket in place.

Only thing I can think of is, that cam sprocket requires a cam button to keep the cam from walking outwards?
IDK

 

responses interspersed

 

Can't see crank dot either; probably at very bottom. Guessing, in lieu of a dot, this set uses another crank sprocket keyway as reference point. We can see two other crank sprocket keyways; keyway on left has a sort of delta "roof", while keyway on right has a rounded quonset "roof". The hidden keyway, likely obscured by chain & at bottom of pic; probably has a squared off "roof". Guessing the squared off & obscured keyway probably indicates "Zero", neither advance or retard cam timing. Again, guessing of what's in pic. Clearly, this no race car. If it were mine, I'd probably have settled on a quality Single-Row set with a larger pitch roller chain (46 links aka pins instead of 58) & with larger dia rollers; as is OE in many Heavy-Duty sbc. However, if OP's timing set fits well, no doubt it'll be fine.

FWIW, the late legendary mechanic-builder Smokey Yunick routinely preferred to install OE Nylon-clad timing sets in true race motors; they damp harmonics from valve train. He did also routinely swap-in new sets.

*edit*
only in exceptional and true race condition, do sbc flat tappet cams have need of a cam button; their tapered lobes push-pull their cams aft with good reliability. Roller lobe have no taper.

 

Well I'm back in the engine. To avoid oil pan and oil removal I swapped in 1.25 inch 5/16 bolts for the four corner oil pan bolts. I left them 1/2 inch undone and then removed all the smaller oil pan bolts. As they came out the pan dropped onto the 4 remaining bolts with enough clearance to remove the timing cover.

The timing cover seal was leaking something weird. The black goo below. You'd think liquid black RTV but used the grey stuff that came with the gasket kit. It was liquid but I had cleaned the pan interior well before install so no ideas.
There is no evidence of improper install or interference. All bolts are tight

And no big signs of interference or scraping

except for these "dings" on the seal shoulder. I can not say they weren't there before, but they look "fresh"

Also the new seal is damaged


I can't get fully in the bay with the rad and shroud still in there for a full on view, but I don't see any scrapes on the timing set.
Since I had finger nails depth groove on the damper snout, I put on the sleeve that came with the gasket set. This is what it looked like.




I have a new Cloyes single row chain to swap in but with no obvious issue I'm not sure I should. I have a new cover to replace my bent and leaking one. (it was leaking at the bottom of the cover between the gasket and needed to be replaced anyway. Wish I had noticed it last time around. Stumped as to rattle for the time being.

 

I'm a little confused by the parts in your installed timing set. That's a GM cam sprocket, not something that comes in a Cloyes kit (at least not the 2 I've bought), and was a '60s GM truck part. The crank sprocket isn't a GM part. Are those May/June 1997 dates? Where did you get the kit?

I'd be inclined to buy a new Cloyes 9-1100 rather than use the mix'n'match parts that appears here. They're inexpensive and you know they match.

 

You have the wrong pan gasket per the pix. The pan is '75 and up but your gasket is for '74 and down. See the gap at the bottom?

Smokey was using a Morse chain, not a double roller.