After swapping out my 305 with a 355 the timing mark never matched up, appeared to be 180* off. Since then I've brought the No. 1 cylinder to what I believe to be TDC (used a small dowl rod to feel when it was on top) then marked the harmonic balancer with nail polish. Ever since I have not been comfortable that I was "exactly" right. Is there any other way I can confirm my settings (without pulling the timing chain cover)?


Thanks

 

Couple of things...

Is the timing tab in the same location on the 350 as on the 305?

Did you reuse the old balancer on the new mtoor?

Are there multiple lines scribed into the balancer, perhaps?

#1 cylinder on a Chevy is driver's side front. I don't mean to insut you with this comment since you probably already knew this but I thought I'd throw it out there anyway.

Being off by 180* is almost impossible since the balancer is keyed to the crank and only goes on one way. It's possible on an old balancer that the outer ring has slipped and the timing mark is off- but 180* is a LONG way to be off.

 

I am not insulted by the #1 cylinder comment.

Yes, it is the original 305 balancer. I know I am close with the new mark the engine runs good. I burn my own chips and want to confirm it's exactly at 6* when I use the timing light and it says 6*.

I wasn't comfortable with setting #1 cylinder at TDC because when I was turning the flywheel to bring the cylinder up, there was some back in fourth play where I couldn't feel if the pistion was really at the top (i could turn the flywheel a couple inches either way and not feel if the pistion was moving - an angle problem).

BTW, this stick i used got stuck between the valve and the piston and I a slight eratic knock - think I bent the push rod (i hope that was all).

Again, thanks for your input.

 

ouch sorry 2 hear about that, next time just put your finger over the hole and feel for compression.. hmm i guess it would be kind hard to get it perfect on tdc for #1 tho w/o being able to line up the timing marks tho..

 

jo88gta,
Did you make sure you had the number 1 piston up on the compression stroke, I made that mistake the first time I pulled the distributor out and you would be 180* out if it is not on the compression stroke. Otherwise the 305 balancer will work as I used mine when I put the 350 in my car.
cc82z-28

 

Right, putting my fingure over the sparkplug hole will tell me I am on the right stroke but not when I am "exactly" on TDC.

Remember, if I wasn't on the right stroke I wouldn't be able to set the timing at all (it would run like sh**) The car runs good, I want to make sure I have my base timing PERFECT.

The ring must have slipped from the original position - because the original grove is no where near where it should be.

 

Then I would scrap that balancer, if it slipped then it is loose and not doing its intended job properly, dampening vibrations.

 

Morely, that's probably good advice. I never thought it had slipped before starting this post. Should the 305 balancer have been a comapatible swap when I dropped in the 355? I thought maybe they weren't compatible.

Thanks again.

 

Only way I know of to find the EXACT TDC on a engine with the heads on it is to use a piston stop screwed into the sparkplug hole, on the compression stroke rotate the engine one way till it stops, then mark the balancer with a fine marker at the 0 timing mark, rotate the engine the other way till it stops, mark it, and true TDC will be in the middle of the two marks.

 

Perfect - where would I get a piston stop???

:hail:

 

Sounds like a wonderful device - especially since I think I've bent a push rod using dowl rod. Have a knock in the engine ever since it got stuck while turning the engine over and it getting caught in there. Had to get under the car and unfreeze the engine by way of turning the flywheel.

 

Do a search on Google, I found lots of stuff by searching for piston stops, here is one place I found that sells the stops...Crane piston stop
And just because it says it's made of brass to prevent piston damage don't believe it, brass is harder than aluminum and will ding the piston if you rotate it too hard, turn the engine very slowly till it just lightly hits the stop.

 

You the man!

THANKS

 

Yes it is "compatable" with all internally balanced small blocks.

 

If you're shoving something through the spark plug hole to find TDC I ALWAYS tell people to take the rocker arms off of both the valves for that cylinder. Your unfortunate experience is exactly why.

Also, it can get confusing- did the PISTON hit the stop or did the VALVE hit the stop?

 

I'm pretty sure the rod was jammed between the pistion and valve, it was flattened and prevented the engine from turning over. I am fairly certain the push rod was slightly bent. Tested compression in the cylinder and it was still at spec and equal to the other cylinders. Car runs good, slight tap every so often. Going to pull the valve cover and pull the rocker arms and push rods tomorrow.

Your help is appreciated - Thanks!

 

Ok, after probably screwing up the engine by getting the rod stuck in #1 cylinder (while searching for TDC), I purchased a new harmonic balancer and resolved the missing timing mark issue. Yes, the outer ring had been slipping continuously.

Now my main concern is the knocking after getting the rod stuck in #1 cylinder. I've pulled the valve cover and checked for bent push rods - all look good. I adjusted the valves and still have the knock. The knock seems noticable only when first starting up and then after letting off the gas and it returns to idle. That's when it's most noticable. I have used a stethoscope and can't quite pin point the fricken problem.

Any advice on narrowing the possabilities??

 

Glad to hear the balancer fixed the timing.... hope you didn't bend a con rod with the dowel.

 

Thanks, Morely.

Any ideas on verifying if I did. Compression check?

 

Hmmm, thought about this a little more after sending you that message. Really cound't have been a problem with the valves - I was on the compression stroke (both valves closed). The rod would have been stuck between the piston and the head (this rod was approx. 1/8" thick and crushable being it was the spring rod that connects to a magnet (for fretching dropped bolts).

Now on to your comment - uhg, the connecting rod. Wouldn't that be a continuous knock that increased with RPM? Going to do a search in a second, but damn if it's the connecting rod. It's a fricken new engine.

Standing in front of the wall with blind fold on - FIRE AT WILL!

 

If it was just one of the flexable, coiled springs on a magnet handle, I couldn't imagine it having bent a con rod. Check and double check that you have all of the plug wires going to the proper cylinders and proper terminals on the cap.
Yes, if you were truly on the compression stroke you shouldn't have bent a push rod. You didn't possibly break off a piece of that thing and have it in the engine maybe?
The knock may be unrelated to what you did to the engine also.

Never, never put anything in the plug hole and use the starter to turn the engine over, a 1/2" drive 5/8" socket on a ratchet over the balancer bolt should do the trick, just turn the bolt in the tightening direction and you'll be good.

 

Yes, that's all it was. But let me say as well, the engine locked HARD, took some serious effort the turn the flywheel back to free it up.

Just got back inside from putting the valve cover back on and running a couple more tests. When I first start the car and it's in open loop with a little higher then normal idle, the engine sounds perfect. Once it goes into closed loop and idle drops back to about 450 rpm, the knock is there. I took off the #1 plug wire and ran it again. Noise it much less if at all. Plug wire back on - and there it is. When I bring the rpms up the noice is much less pronounced, if at all. Can't tell for sure if it's there with or without the stethoscope, to much other noise. Does this help narrow the possiblities??

 

That's not exactly sound advice either.

I've seen WAY too many incidents where guys have stripped the threads in the crank snout.

Get yourself on of these


You can click on the pic for more info.

 

It sounds like your piston is getting cocky. (Cocking sideways in the cylinder)

It's possible that you got the thingy you stuck in there (I've done that a few times to ) got wedged between the piston and the cylinder wall and possibly broke the top ring.

As much as you hate to hear it, it's time to pull off the head and look.

 

I really don't think so, I'm looking at it right now and the piece at the end is squashed, not missing. It's not that hard of metal, it's also not brittle. No smoke, high compression - the noise goes away when the rpm's are up a bit. Very confused by this one.

 

Never had or heard of a problem doing it by the balancer bolt. That device is fine, if your crank pulley isn't on, but his is on and would require removal to use it.
To each his own.....I turn my crank by the balancer bolt and have done so for well over 20 years with nary a problem, from small to big blocks, with and without plugs installed.

 

WOW!!! That would require WORK in order to do it the right way. Seems to be a common problem these days.
AND HERE'S YOUR PRIZE!!!


I'm just messing with ya.

It may have worked for you, but the ONE TIME this guy does it his crank snout would get stripped. It's called Murphy's Law.
If I ever meet that Murphy guy......!!!!!!

 

BOY, am I glad to see this post. I put a carb manifold and HEI dist. on my LT-1 motor, all that went great with the exception of the timming marks, it seams the balancer on the LT-1 doesn't have timming marks on it since there is no base timming adjustments (all computer). I did almost the same thing, I pulled the spark plug and looked in the cylinder with a light then turned the motor over by hand untill it was on the compression stroke and it looked like the piston was at TDC, then marked the balancer by using a dremel and cutting a small grove in the balancer. however, I have never been 100% confident about the timming. I have been avoiding pulling the head just to find TDC. and I think this will do it for me.

by the way, what size plugs do we use in our engines, the 12 mm or the 14mm????

 

I really can't fathom how you'd strip out those threads unless there was something wrong to begin with. I checked it out and there are no less than 10 threads engaged in my crank snout from the bolt, if they gave way from turning the engine over I'd bet the crank was defective.
But if you don't want to take a chance you could always "HE-Man" the thing around by the crank pulley by hand.

It'd be nice if you could get a device like that which would bolt inside the crank pulley and you could just leave it there...maybe I should come up with something and make some money....

 

Actually you could use that thing. Just use longer bolts and some Loctite.

I wouldn't do it. I don't need to since I'm "HE-MAN"!!! :sillylol:

You should see "SHE-RA"!!!