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
Timing 80 degrees off?!?
Jan 02, 2006
12 Replies
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.
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.
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
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.
formatting link
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. :/
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
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.
Bill likes the fancy balancer with "Summit Racing" on it. This is called "posing". ;^)
Earle
Join the Discussion
Have something to add? Share your thoughts — no account required.
Didn't find your answer?
Ask the community — no account required