How interchangeable are 318 harmonic balancers?

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ProjectBazza

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As I mentioned in my introduction (link: New member with an interesting story. ), I'm working on a '71 Chrysler VG Valiant with a 318 from Australia, and amongst a couple other things I'm currently working on, I'm in the middle of changing out the timing chain. During my testing on the chain I noticed the TDC mark on the harmonic balancer didn't line up with the marks I got when I used my TDC tool, so as long as I have it out, I'm wondering about replacement options.

The owner of the vehicle wants to keep the car as original as possible, but I can't find a da** thing when I Google the P/N found on the inside of the original damper, so here are my questions:
1. How interchangeable are these? I see all sorts of dampers available for 318LA's, but I don't know which one(s) to pick. Or avoid.
2. Given that this is an Australian engine, would there be a US equivalent damper I could use, or is the same damper used regardless of geography (i.e., here in the States)?
3. And lastly, is there an aftermarket damper I could use that looks like this one? I'm not trying to "pull a fast one" on the owner, but rather the back sides of the dampers I'm seeing online don't match what I have here in my hands.

Any and all useful input will be sincerely appreciated!

Thanks.

Jim

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318s are all internally balanced, so the harmonic balancers are interchangeable, with 2 caveats:
The bolt pattern- '69 and earlier had one offset bolt, '70 and later were perfectly symmetrical.
The timing mark changed location in '70 when they changed from the cast iron water pump with a drivr's side inlet to the aluminum pump with a pass. side inlet.
 
Yep! They should all be thin dampers with no added metal like a 360 balancer has.
 
The timing mark changed location in '70 when they changed from the cast iron water pump with a drivr's side inlet to the aluminum pump with a pass. side inlet.
That seems to agree with what I have here (fuzzy freeze-frame screenshot from a video I sent the owner a few days ago):

Screenshot (52).png


I'll check the bolt spacing tomorrow evening after work, thanks.
 
Has yours slipped? Or is it being used with the wrong water pump/timing mark setup? Yours may be just fine.
 
Can you show us the Damper's crankshaft keyway in relation to the TDC (top dead center) mark slot?

So we can look and compare to what we have here, to guess > see if it has moved?

20230723_214645.png


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Here are a few 318 dampeners I have on hand. Looks as though they are correct and have not slipped.

'70 and newer 318s with passenger side exit aluminum water pump. Timing mark casting is on the driver's side of the timing chain cover.

'68 - '69 and earlier (red painted blocks) have cast iron water pump that exits on driver's side. So the TDC timing marks are on the passenger side. So that would put the earlier 318's damper TDC slot in a different place on those early years.

Here is a '71 318 dampener:

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And another 318 Dampener.

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Check your crankshaft Keyway in relation to the TDC slot on your dampener.

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What you guys really don't understand is in Australia CAL imported the engines in batches so our 1971 model car might have a 1969 USA engine in it from the factory. If it has an alloy water pump it is a late engine but if it has a cast iron water pump it is an early engine.
So the timing mark on the left ( Aussie passenger side) is late engine and timing mark on the right (Aussie drivers side) is early engine. I am not sure when Chrysler Australia changed the engines but by VH they were late but the VG model had a lot of hybrid parts in them.
Balancers are easy to get and Rocket industries usually has stocks available in Australia!
P.S. the early engines timing cover did not have a cast in timing mark but had a bolt on timing tag on it!
 
I am not sure when Chrysler Australia changed the engines but by VH they were late but the VG model had a lot of hybrid parts in them

That's exactly what I've been finding as well, but not only for engine components. The majority of the engine compartment seems to be straight out of Detroit (so far), while the electronics (gauges, senders, etc) were supplied by VDO, and don't use the same resistance values as US vehicles.

I either pity anyone who does a concourse restoration on one of these, or have immense respect for them.

P.S. the early engines timing cover did not have a cast in timing mark but had a bolt on timing tag on it!

Thank goodness this is a "late" vehicle, as I can't tell you how many bolt-on timing marker pointers I've misplaced for my Fords over the years!
 
Has yours slipped? Or is it being used with the wrong water pump/timing mark setup? Yours may be just fine.
Based on my TDC tool it appears it has slipped a little under 10 degrees. Of course it could be "user error", as my eyes ain't what they used to be, and I'm doing this hunched over the engine bay with a bad back, but....

But the engine is original, and I've been told by the owner more than a few times that in the interest of originality, no one has messed with anything w/o their knowledge or consent (same family since new).
 
Can you show us the Damper's crankshaft keyway in relation to the TDC (top dead center) mark slot?

So we can look and compare to what we have here, to guess > see if it has moved?

View attachment 1716118802

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I'll try to grab a couple photos of it when I get home this evening. I'm supposed to help my wife with a couple things after dinner, but.....

:lol:
 
Here are a few 318 dampeners I have on hand. Looks as though they are correct and have not slipped.

'70 and newer 318s with passenger side exit aluminum water pump. Timing mark casting is on the driver's side of the timing chain cover.

'68 - '69 and earlier (red painted blocks) have cast iron water pump that exits on driver's side. So the TDC timing marks are on the passenger side. So that would put the earlier 318's damper TDC slot in a different place on those early years.

Here is a '71 318 dampener:

View attachment 1716118804


View attachment 1716118805

And another 318 Dampener.

View attachment 1716118806

Check your crankshaft Keyway in relation to the TDC slot on your dampener.

☆☆☆☆☆
Nice!! I'll compare mine to these.

Thank you!!

:thumbsup:
 
Based on my TDC tool it appears it has slipped a little under 10 degrees. Of course it could be "user error", as my eyes ain't what they used to be, and I'm doing this hunched over the engine bay with a bad back, but....

But the engine is original, and I've been told by the owner more than a few times that in the interest of originality, no one has messed with anything w/o their knowledge or consent (same family since new).
With a piston stop there is very little user error. Rotate one way until it hits the stop, mark zero. Rotate the other way till it hits the stop, mark zero. Halfway between will be TDC. Slipped is slipped wether 10 or 100 degrees. You’ll need a new one.
 
Well, now. This is interesting.

In terms of timing marks and keyways, the balancer out of this vehicle looks very similar to the pictures of the "good" balancers that George Jets posted above:

IMG_4285 crop.JPG


And as TT5.9mag pointed out, "slipped is slipped", so they're either right, or they're not (I'm paraphrasing).

(Or I did the TDC check right, or I didn't.)

I guess I won't know until the new TC set arrives, as I sure as he** won't be turning anything until I get this buttoned-up again:

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As for the bolt holes, they're not symmetrical, which, if this was a US vehicle, would mean "69 and earlier", according to Professor Fate.

IMG_4289.JPG


But this is a '71 vehicle....

...the VG model had a lot of hybrid parts in them.

Amen to that!
 
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318s are all internally balanced, so the harmonic balancers are interchangeable, with 2 caveats:
The bolt pattern- '69 and earlier had one offset bolt, '70 and later were perfectly symmetrical.
The timing mark changed location in '70 when they changed from the cast iron water pump with a drivr's side inlet to the aluminum pump with a pass. side inlet.
It's actually '71 and earlier use the staggered bolt. Starting in the '72 model they were symmetrical. That part doesn't matter all that much as the one offset hole in the pulley can be filed to accept either balancer. The timing marks changed when they went from the cast iron water pump to the aluminum type. The timing cover changed then too when the timing marks went from the right side to the left side (passenger side and driver's side on LH drive cars). There were also a few different balancer appearances. Some were like the OP's that have a flat forward surface on the outer ring along with a semi-hollowed slot in the ring on the timing cover side. There are also versions that are flat on both sides. So, it looks to me like the OP needs a '70-'71 318/340 balancer if he wants an exact replacement. If he can live with slotting the crank pulley, he can used the '72-up version. If he wants to cut a new ignition timing slot in the outer ring, he can use the '69 and earlier balancer. There are also businesses that can rebuild your balancer if you want to keep the original part.
 
I am (was!) buttoning-up the engine this weekend in preparation for putting it back in the car when I found two of these:
IMG_4443.JPG


Left rear, and right front exhaust studs broken off about 1/8" inside the head. They're fixed now, but...that was fun! (insert sarcasm here)

Anyway, back to the harmonic balancer issue.

I got the TDC/piston stop tool out again to check "indicated" TDC (so much easier to do with the the engine out of the car!), and each time I came up with the same answer/result. On the last attempt I ran out of tape (thus it became my last attempt), so bear with me on this picture.

The heavy pencil line to the left (or top) is the correct "before" point, and while it's hard to see here, there is another pencil line right at the end of the tape for the "after" point.
IMG_4451.JPG


Needless to say the TDC line on the balancer is not centered between the two, and according to the timing marks on the cover (when I "center it up"), it looks like it's about 6 degrees off.

If you will recall the owner, Bazza, started taking the engine apart because it was running like sh** and overheating. Then he got sick and ended-up in the hospital. Between this, the stretched timing chain, an original distributor with worn-out bushings, and what I'm sure are more than a few vacuum leaks (power brake booster line was REALLY bad), I think I'm finally making some progress toward getting this running again.

I'll leave it up to Bazza whether to get the OEM balancer rebuilt or not, but I need to get it running , so I'm off to buy a new balancer.

Thanks, everyone!

Jim
 
There will be much more of that motor made/cast in Australia than you suspect.

A country with a history of mining and quarying had pleanty enough engineering capability.

The car you have has suffered that "miles away from home" neglect by the look of things...

Or was purchased from a "just need it gone" situation.

The Australians made the balancers and covers as a matched pair. if they could make a balancer for a hemi 6 they can make a 318 one.
Something is amis with your combination, but any cover off any LA 318 will fit but may not have the tab in the right place.

if you take the attitude that its a 1968 car you won't go far wrong.

wait till you get onto the brakes.... :) what a mixture... :)
small balljoint/ small inner bearing stub axles with 4 or 4.5 inch PCD.
3.5 inch mounting like US for calipers but the kelsey hayse stud bracket is smaller than US
rear is 9 inch drums. rockauto can help in all area but Borgwarner specifc back plate.

The Aussie engine plant in lonsdale SA was built at great expense in the mid 60s to provide hemi 6 motors for the world market, that currently had been using slant 6 engines.
It was a marval of modern engineering with 3 engine dyno rooms and state of the art casting facilities, technology straight off the back of the LA engine programme in the US.
biggest and most technically up to date engine plant in the southern hemisphear when built.
Doomed to unprofitability and under-use due to chrylser US pulling the plug on the hemi 6 becoming the all markets 6 cylinder WORLD ENGINE of the 70s

The Aussies cast the 225, 215-265 hemi 6, 273 and 318 blocks n heads

They had the equipment and expertise. local and seconded from Chrysler in the US.

they made steel and cast cranks, cast oil pumps, pressed rocker tins and front covers,

locally made water pumps. pressed rockers of all types

the hemi 6 used pressed ballstud mount rockers, the australians managed success here where the US parent company didn't.

Deicated teams and high quality. materials were good, you'd be hard pushed to find a bellhousing that needs offset dowels and its quite hard to break the tiny 7 3/4 inch borgwarner diff used .

If you check the con rods from an aussie 318 or indeed 225 or 265 the small ends are prefectly in the middle of the small end casting.

show me a US set where that is the case, 4 of the 8 will be offset.
both are dimensionaly correct, centre to centre, but one inspires more confidence than the other.

they also persisted with Higher CR motors longer due to the slower impact of smog rules
they imported 340s 360s complete and 904 and 727 complete

but the vast majority of cars had locally produced engine, trans and axle.


Dave
 
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Ok, so,........I'm baaaaaack! (And given my day at the office today, I wish like he** I wasn't.)

I ordered a new balancer from Summit Racing a couple/three days ago, and it showed-up today. Before I even installed it all the way I did a TDC test and checked the timing marks. Everything looked great, so I bolted 'er in, and did it again. Twice. Both times I got very similar results (albeit different marks on my tapes, obviously), and here's a shot of the second test (pay no attention to the "x" line):
IMG_4489.JPG


That TDC mark is da** near perfectly centered when I measured it out: 7/8" both ways, right on the nuts!

So everything was great, right?

Nope.

Turns out the bolt holes for the pulleys in this new damper are equidistant from each other, but....well....

Here. See for yourself:
IMG_4492.JPG


The damper I bought is supposed to fit a '68 to '72 318 engine (I used a Dart as the Model on Summits site), and this one is a '71, so what did I do wrong?

(Reminder, this is a 1971 VG Valiant from Australia, RH drive, water pump dumps on the right, and the TC marks are on the left side, on the cover).

Here's what I bought (and I'm sorry it's sideways):
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I doubt I can return it, as it's been installed, but now I don't know what to buy.

Can anyone direct me to the right part this time?

(Also, I may have a VERY lightly used 318 damper for sale soon, if anyone needs one.)

Thanks in advance, people. I'm going to slink-off and lick my wounds for the evening.

Signed,

Frustrated Jim

P.S. The original damper still looks good, and I don't see any cracks in the rubber ring, but here's proof positive that they can slip and still look good.
 
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I'd just oval out that one hole in the pulley with a Dremel or die grinder until a bolt can go through to the damper. I did that on the crank pulley I have probably 15 years ago and it's been on multiple small blocks since then revving past 5,000 RPM countless times. I suppose it's not "restoration correct" but once the engine is in the car with the radiator in front of it it's literally impossible to see the damper/pulley bolts. That Summit damper isn't exactly a restoration piece anyway... but probably better functionally.
 
I'd just oval out that one hole in the pulley with a Dremel or die grinder until a bolt can go through to the damper. I did that on the crank pulley I have probably 15 years ago and it's been on multiple small blocks since then revving past 5,000 RPM countless times. I suppose it's not "restoration correct" but once the engine is in the car with the radiator in front of it it's literally impossible to see the damper/pulley bolts. That Summit damper isn't exactly a restoration piece anyway... but probably better functionally.
Agree'd. New replacement pulleys come with a an oblong hole to accommodate symmetrical and asymmetrical dampers. The washer on the pulley bolt will cover the oblong hole as long as you don't go nuts with the grinding.
 
If it was just the one pulley that would be simple, but there's about 2" of aluminum spacers (plural), and three different pulleys on there. (No pics, sorry.)

The pulleys I could hog-out, no problem. But the spacers- no way!
 
I just found a picture of one the spacers from when the engine was still in the car:
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The other spacer is still attached to the pulleys at the bottom of the picture.

I can't really make those holes bigger, but now I'm wondering if I couldn't use the slots between the bolt holes....
 
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Why so many spacers? Did the dude have the crank pulley on backwards? I would think that with the crank spacer, the wp pulley and alt mounting would all have to be modified..........Wouldn't that push the fan into the rad?

Edit........Maybe the WP pulley is the old style for a cast water pump which would be more shallow, necessitating the crank pulley to be spaced outward?

Sorry, just spit ballin'
 
Yes that is the Aussie style spacer and yes just use a rat tail file and elongate that spacer as everyone of us mopar philes have done in the past.
 
Thank you for the responses.

Last night I took the middle-of-three spacers and opened-up the oddly-shaped spaces between the holes (see my picture above). Then I installed six studs in the new balancer to see if this "opened-up" spacer would fit over the studs, and it works!

I'll open-up the other two spacers, and "massage" the pulleys, this weekend sometime.

Thanks again.

Jim
 
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