Timing 80 degrees off?!?

Whoof! Check this out. I went out to recheck timing with a degree-able timing light this afternoon and couldn't find the mark. (Been working with octane and timing to get rid of a slight rattle.) I used a white crayon to mark it, then orange, then sharpies but still couldn't see the darned thing in daylight. "Hmm. I'll just wait til tonight." I finally found it tonight... somewhere around 80 degrees off! (This measured in cam degrees, so, almost the far side of the balancer.) Since I totally screwed timing in the day, I eventually tried timing from the #2 cylinder (yeah, I know that's not how you do it but it was almost right on #2:( It runs really smooth now but motor pings like a can-o-bearings upon anything more aggressive than smooth throttle (goose it, get on it, etc.) It's a Chevy 5.7L V8 with TPI and, yes, I disconnected the bypass. I put the engine together right, numbered all the wires, installed the HEI distributor in the correct position, put in a new timing chain, etc. So, anybody had this? I don't think the timing chain jumped since it's new and slackless. There's no slop in the ignition, apparently, since the timing light shows the timing mark's rock-solid steady. Harmonic balancer outer ring slipped? Ideas anyone? Troubleshooting tips? How many things could it be?! Drink P.S. Next time, I'll confirm timing mark position upon assembly and make a hashmark between the inner/outer ring on the balancer. '76 CJ-7 '87 Chevy 5.7L V-8, TPI NV4500, Dana300

Reply to
Drink
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Reply to
L.W.( ßill ) Hughes III

Drink did pass the time by typing:

That would be my first thought.

Like bill says, find TDC on cyl#1 and go from there.

By the way, plain ol chalk works great for timing marks. That dayglo stuff or the plain ol white chalk.

Reply to
DougW

That shouldn't be a problem for the time being, should it? The balancer's not weighted on the 350 and I should be able to get it timed correctly til I can get a new one.

Reply to
Drink

Nailed it. Went back out to take a second gander with a clear, logical head. Looking at the harmonic balancer from the underside of the engine, I can see that the outer ring's slipped, most definitely. Looks like the outer has slipped backwards off the inner about 3/4" and barely scrubbed the timing chain cover. This could get expensive... I've got an '87 350 that should come out of the machinist' soon. I was planning on eventually putting it and a 218 LT4 hot cam under the TPI (and maybe a ported set of 186 fuelie heads) into the Jeep. Now, if I can get the other motor back. The sooner I can get the other block back, the sooner I can build up a Trans Am and take it to the track instead of... Ahhh, who am I kiddin'?! I'll still have fun with the Jeep and throw big, flumpy clods off-road! But, I'll just drive one while working on the other. This is gonna be cool. Oh, and Bill, I promise I won't make the Jeep any faster; no stroker cranks, no nitrous, no 14:1 forged pistons. I couldn't put any more horses to the dirt. Haha!

P.S. Hey Bill, I promised you a photo back before I put it together. I'm almost done with the bugs so I'm sending you a couple photos via e-mail. It turned out more than sweet and you gotta see this; I think you'll be able to appreciate it! If anybody else's curious, let me know and I'll forward. Drink

Reply to
Drink

Drink did pass the time by typing:

Only if it slips far enough to cut the cover and drop oil. :)

Dunno about your application but replacing the HB on my 4.0 only took part of a day.

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Fairly easy but having the right tools is a necessity. I could have done it without removing the radiator if they had an installation tool that was about 2" shorter. :/

Reply to
DougW

Reply to
L.W.( ßill ) Hughes III

300 bucks for a harmonic balancer???? From where? Do they wear ski masks and tote guns? Unless it's a LOT different from the one on my '77 Cherokee, that's highway robbery! Have they changed? And nearly all of the ones in salvage yards are perfectly good. (That's where I got my current one, five years ago.) And rebuilt ones are probably available, too.

Dan

Reply to
Hootowl

Reply to
L.W.( ßill ) Hughes III

Chevy harmonic balancers are the same for 283, 305 and 350. Get one from a boneyard. I had to replace one on a 305 and found out that they are the same. Mine had separated and cut into the timing chain cover. All I could get was chromed. That looked funny on an old beater car.

Reply to
Scott in Baltimore

Reply to
RoyJ

Bill likes the fancy balancer with "Summit Racing" on it. This is called "posing". ;^)

Earle

Reply to
Earle Horton

Reply to
L.W.( ßill ) Hughes III

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