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440 timing mark

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old hatt

Contributing Member
Sorry guys here I go again. I am assuming that my 440 is timed through the inspection hole on the bell housing since I have no markings or indicator on the harmonic balancer even though my service manual says there is. My question is I do not see a mark or indicator on the bell housing to compare to something on the flywheel. HELP
 
A vacume gauge that measures inch pounds can be used you will need to locate a port on the manifold or carb but it has to connect below the throttle plate with engine running turn distributer slowley until maximum vacume reading back off apx 2to3 in pounds. another method is using a piston stop remove all apark plugs insert screwdriver in #1 cyl rotate crank manualy until piston is at top continue just past install piston stop in cylender adjust stop until it bottoms out against piston rotate to apply slight pressure between stop and piston mark the balencer and timing plate cover togeather now rotate crank until piston contacts stop mark balencer and plate using a tape measure to find center place a mark on plate and balencer you now have a mark indicating top dead center the advance marks can be added by coppying from another cover junk yard parts house soforth. for you IO gurues have i missed anything???????
 
old hatt said:
Sorry guys here I go again. I am assuming that my 440 is timed through the inspection hole on the bell housing since I have no markings or indicator on the harmonic balancer even though my service manual says there is. My question is I do not see a mark or indicator on the bell housing to compare to something on the flywheel. HELP
Click to expand...
old hat, I think that if the flywheel is to be used, the flywheel cover (aka bell housing in the auto world) will have a corresponding mark somewhere on it also.
This mark, along with the degrees on the flywheel, could be used for ignition timing.
If no marking, then see #2 below.

MIDNIGHT EXPRESS said:
1... A vacume gauge that measures inch pounds can be used you will need to locate a port on the manifold or carb but it has to connect below the throttle plate with engine running turn distributer slowley until maximum vacume reading back off apx 2to3 in pounds.

2.... another method is using a piston stop remove all apark plugs insert screwdriver in #1 cyl rotate crank manualy until piston is at top continue just past install piston stop in cylender adjust stop until it bottoms out against piston rotate to apply slight pressure between stop and piston mark the balencer and timing plate cover togeather

3... now rotate crank until piston contacts stop mark balencer and plate using a tape measure to find center place a mark on plate and balencer you now have a mark indicating top dead center the advance marks can be added by coppying from another cover junk yard parts house soforth.

for you IO gurues have i missed anything???????
Click to expand...
MIDNIGHT EXPRESS,
1.... I would not be able to recommend this method.
If you've read some of the threads regarding Marine Gasser ignition timing, you'll know just how critical these numbers are. We can't hap-hazardly throw Ignition Advance at a Marine engine without risks......, Detonation being the largest risk.

See old hat's earlier thread m440x timing ! We still need OEM Ignition Advance specs for the 440 Marine engine.

2... Yes, great idea for when cylinder heads are in place! :)
pic_installation.jpg

This is called a PPS (positive piston stop) procedure.
If all else leads us to a dead end, this is what I'd recommend doing.
It requires some set up and time to do it......, but when done correctly, it's pretty much goof proof!


3... IMO, it is best to temporarily install a 360 degree wheel onto the crankshaft.
images


You'll be using a temporary adjustable wire pointer aimed at the degree wheel.
I prefer to use 30* +/- for the BTDC/ATDC stop (the larger the spread, the greater the TDC accuracy will be, and visa-versa).
When an equal amount of degrees has been established in either direction of the "stop" (the 30* +/- mentioned), we can then carefully remove the PPS.

With the PPS removed, we now rotate the engine until ZERO is in the target of the wire pointer.
(do not bump the wire pointer during this)

Now we remove the degree wheel (without moving the crankshaft), and re-establish our TDC marking between the balancer and tab indicator.
Once TDC is established, we can go from there to the correct balancer markings, etc.


While you're at true TDC, you may want to punch the flywheel and flywheel cover.
This way you'll have a permanent TDC marking as long as the same F/C remains on this engine.


Old Hat, this can get quite involved to do, but will leave you with NO Doubts regarding true TDC.
It's a one-time-deal also.
 
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"I have no markings or indicator on the harmonic balancer even though my service manual says there is."

I would think you have at least one mark on the damper. If not you'll need the degree wheel and piston stop to verify and mark tdc if you are going to use the damper to time.


Bolt on tabs are available at 440 source, ebay, etc., if the timing cover doesn't have it. You would still need to verify the mark on this as zero may not be accurate.
BBtiming tab.jpg



Also, timing tape is available for the 7.25" damper. (1/16" = 1° if you want to scribe it yourself)


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Ricardo thanks for your reply dido on vacume method. how does engine temp and fuel quality and incorrect timming effect one another. does the balancer need to be reoved to use degree wheel?
 
Ok everyone hold on here. The mark on the flywheel is hard to see when old and rusty, take the #1 spark plug out and bump the engine over while plugging the whole with your finger, after the compression starts pushing your finger out turn the engine over with a socket and breaker bar while holding a pencil on the piston, slowly rotate the engine until the piston is at TDC. You will now see the old faint mark and can put a drop of white paint on it. The timing tab has 10-0-10 so it can be used for either rotation, Be careful as I have seen engines set at 7 degrees after TDC instead of 7 degrees BTDC.

Dan
 
MIDNIGHT EXPRESS said:
Ricardo thanks for your reply dido on vacume method.
1.... how does engine temp and fuel quality and incorrect timming effect one another.
2.... does the balancer need to be reoved to use degree wheel?
Click to expand...
1.... Whoah..... that would require about 10 pages of typing, and about two hours or more.
I'll nut shell it for you: Short of NO OIL and/or Over-Heating, but of no less importance, Ignition Induced Detonation is the Marine Gasser's worst enemy.
Don't confuse "pre-ignition" with "detonation"...... these are two entirely different animals.

2.... Short answer.... NO! You may need to temporarly replace the bolt with a longer one.

tolly_family said:
Ok everyone hold on here. The mark on the flywheel is hard to see when old and rusty, take the #1 spark plug out and bump the engine over while plugging the whole with your finger, after the compression starts pushing your finger out turn the engine over with a socket and breaker bar while holding a pencil on the piston, slowly rotate the engine until the piston is at TDC. You will now see the old faint mark and can put a drop of white paint on it.
Click to expand...
Dan, that would certainly work if attempting to approximate TDC. If the OEM mark is there, it will work.

Be careful when turning a crankshaft with the Harmonic Balancer bolt. Snap that baby off, and you'll be cursing yourself.
To be safe, and since we're not concerned with camshaft drive chain slack, rotate the engine in a direction that would loosen this bolt, not further tighten it!
TDC comes up twice in 4 cycles..... so it doesn't matter when checking the phase of the balancer or flywheel re; TDC.
 
Could someone tell me where on the flywheel housing the indicator would be. I have removed the rubber flap held on by the 1/4" bolt and can see no marking of any kind.
 
Jeff, I think that Old Hat sees the mark on the flywheel, but sees no corresponding marking on the flywheel cover itself.

Old Hat, it could be that this engine was never intended to be timed from the flywheel, even though the flywheel itself is marked off.

I would do the PPS procedure, and be done with it.
It's a hassle, but well worth knowing that you have established a true TDC.
Like said, both the harmonic balancer and flywheel cover can be marked at the same time.
Now you'd have two TDC sources.
 
I saw the paint mark and in no way did I think that is what I was looking for. I am going to use it and do the pps procedure too. Thanks once again guys for all your help!
 
Mopar used an arrow-shaped sheet metal pointer that was bolted to the bell housing. Guess it kinda fell off?

Jeff
 
That tab is marked up to 10 degrees only from what I can see. (there may be a 15, but it's rather vague)

attachment.php


10 degrees will allow you to set BASE, and that's about it!

I know that I'm a real NAZI when it comes to Marine Engine Ignition Timing, but this stuff is just too dang important to fool around with.

We need to see accurate BTDC markings up to around 30-35* in order for these to be useful!
(unless you are willing put your faith in the Digitally Advaning type timing light, and do so without risk of user or equipment error)


.
 
Appreciate the picture of the riveted plate. Still a little confused though with the plates positioning. It must fold into the opening below it in order to get a reading. Can anyone tell me the distance between the TDC and 10 mark? Rick you can be a Nazi about this all you want as I saw first hand this summer for the first time just what damage this problem can cause. I sure had an unhappy dock mate in July.
 
old hatt said:
........... Rick you can be a Nazi about this all you want as I saw first hand this summer for the first time just what damage this problem can cause. I sure had an unhappy dock mate in July.
Click to expand...
And that's why I'll continue to be the NAZI on this!
Well, at least as long as you guys allow me to be! :D
 
Well, the 15 doesn't help much either when checking Ignition TA, but thanks for that.
With the narrow opening in the flywheel cover, we'd be better off if the flywheel perimeter was indexed, and then use a single TDC mark on the tin plate, or on the flywheel cover itself!
 
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Tahoerover said:
Never seen that, the two 440s and the 426 I work on have a riveted on scale
Click to expand...

This is exactly what my 440s have, it's very easy to use once you clean up the mark in the flywheel. Since I converted my ignition to Pertronix 10 years ago the timing has never had to be reset, it never changes. My manuals are on my boat but I think the timing is set to either 5 or 7 degrees btdc, let me know if you don't have your original manuals.

Dan
 
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tolly_family said:
This is exactly what my 440s have, it's very easy to use once you clean up the mark in the flywheel. Since I converted my ignition to Pertronix 10 years ago the timing has never had to be reset, it never changes.

Dan
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OK.... a bit of sarcasm in this, but take it with a grain of salt.
And Dan, this is for all of us, not aimed at you in particular.
  • **How are you checking the TA (total advance) with only 15 degrees of available markings?
  • I know of NO gasoline Marine Engine that will operate on 15 degrees of TA.
  • Are you setting BASE advance only, and then walking away?
  • Are you checking BASE Advance only in the future, and assuming that your mechanical advancing unit is doing what it's suppose to be doing after 5-10 years of service?
** This would exclude the use of a digitally advancing timing light if you are comfortable in doing that for your Marine engine.

Raz me if you want to.... in certain circles, I'm known as the Ignition Timing NAZI...... I can take it. :D

.
 
I actually have checked the total advance on my boat with an adjustable timing light but I have never heard of another marine mechanic or owner ever doing that. I have all the original manuals and nowhere does it say what it's supposed to be. I think mine is 25-28 degrees.

I have had a race car for 40 years and know how to set them up, my family used to have a 1948 40' Chris and the procedure for timing it was to turn it until it pinged under full throttle and then back it off a little.

So now looking a stock 440 I say just set it where it's supposed to be and go boating. Thats exactly what all the mobil marine mechanics do when tuning my dock neighbors boats. My yacht club docks are full of old gas powered boats including Lincolns, Hemis, 4 boats with 427s, several 440s and a bunch of 454s and most are original engines that get tuned up once a year by checking the base timing.
 
Dan, Oldhat,
If you set initial @ 5-7° BTDC with a light on the flywheel at idle, if you have not already, check to see if another mark shows up @ 2200 - 3000 rpm. Maybe the flywheel has a mark already on it for total. Worth a shot?
 
Oh no...... I'm allowing myself to get sucked in once again. :D Dam it......., I'm one hard headed guy, aren't I? :mad:

For you "Nah Sayers"......... are any of you guys familiar with marine load detonation, and what the damage looks like if it were to occur?
If not, take a quick look here. These aren't all Marine pistons, and they aren't all from the same degree of detonation, but it should give us a good example of what to expect should our ignition timing Total Advance be too great and too early!

The catch is often "just how close are we to detonation"?
Are we receiving enough TA for performance, or are we leaving horse power on the table?
(often the OEM specs are very conservative)
Are we so close that given the right load, poor fuel quality, the right atmospheric conditions, over-propped, etc, that we risk detonation?

The only way to be safe, is to use the OEM specs for the particular Marine engine, and make sure that the distributor (or EST system) is giving us this.
The engineers have spent countless hours researching this.

Setting BASE only tells us ZERO of what TA is, unless we take it further by actually checking it dynamically, and at the RPM at which it is to be "Full In".

daves69 said:
Dan, Oldhat,
If you set initial @ 5-7° BTDC with a light on the flywheel at idle, if you have not already, check to see if another mark shows up @ 2200 - 3000 rpm. Maybe the flywheel has a mark already on it for total. Worth a shot?
Click to expand...
Excellent point!
Keep in mind that Marine Engine ignition induced detonation can begin as early as 2k rpm and up.
This why the Igntion advance is "Progressive", and for the most part, linear.

tolly_family said:
I actually have checked the total advance on my boat with an adjustable timing light but I have never heard of another marine mechanic or owner ever doing that.
Click to expand...
I too have spoken with (and heard of) the so called "Marine Mechanics" that never look past BASE advance.
I think that these guys are doing a disservice to their customers.

That's like checking the air pressure on one tire, and then kicking that tire........., and then going around to the other three tires, and giving them a kick ONLY!


tolly_family said:
I have all the original manuals and nowhere does it say what it's supposed to be.
I think mine is 25-28 degrees.
Click to expand...
The 25-28 degrees is great to know if these are correct for your Marine engine......, but without an associated RPM, the numbers are meaningless.
Is it 28* @ 2k rpm?
Or is it 28* @ 3k rpm?
Under Marine Engine loads, 28* @ 2k rpm is a recipe for detonation......, IMO.


tolly_family said:
I have had a race car for 40 years and know how to set them up,
Click to expand...
Then you know full well about LPCP or PCP, and what this means.
It becomes of more importance for the Marine gasser.
We'll find recommendations for PCP at/near 12-14* ATDC for many piston engines, including diesel engines.
Doesn't matter what the bore/stroke is..... crankshaft angle is crankshaft angle.
For the gasser, ignition timing plays a very large role in this.
Being a race car enthusiast, you certainly know this.

While under Marine loads, a PCP of 10* ATDC may cause some real issues... or be very close to it!


tolly_family said:
my family used to have a 1948 40' Chris and the procedure for timing it was to turn it until it pinged under full throttle and then back it off a little.

So now looking a stock 440 I say just set it where it's supposed to be and go boating. Thats exactly what all the mobil marine mechanics do when tuning my dock neighbors boats. My yacht club docks are full of old gas powered boats including Lincolns, Hemis, 4 boats with 427s, several 440s and a bunch of 454s and most are original engines that get tuned up once a year by checking the base timing.
Click to expand...
Pre-Ignition and Detonation are two entirely different phenomenon.
People often confuse the two.
To set the ignition timing a Marine engine by listening for a "ping" is simply incomplete and irresponsible.... but this is my opinion only!
No offense to any of us..... just say'n!



As we've seen here, the 440 TA specs seem to be rather illusive..... and I wish that someone could find them.
Once found, I say follow them...... but make darn sure this is more than just BASE.


.
 
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I was just closing out my Google page (where I found the Piston Detonation images), and I found this image linked to an Aircraft Engine forum.
Kind of cute, and it makes the point regarding normal combustion -vs- Detonation.

combustion.gif


This one is kind of cool!
PCP or LPCP is to occur at/near 12-14* ATDC....... so you'd have to imagine where the crankshaft is after initial combustion.
In theory, and while the burn continues......, peak cylinder pressure is to occur @ 12*-14* crankshaft angle, after top dead center.

ae3.gif

Wow.... I can hardly keep up with that one!


Let's slow things down a bit.

4StrokeEngine_Ortho_3D_Small.gif



Here's another one, and you get to change the speed of it.
Under "veiw", invoke "piston".
Under "stroke" invoke "power".
As the crankshaft approaches 12-14* ATDC, this when cylinder pressure is to be the greatest.
Every component, including ignition timing, has this for the main goal.
 
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Both videos are Keepers!

Thanks, Rick. I'll be using them in my USCG Aux boating class on "Powering Your Boat".

Jeff
 
fastjeff said:
Both videos are Keepers!

Thanks, Rick. I'll be using them in my USCG Aux boating class on "Powering Your Boat".

Jeff
Click to expand...
What.... no chastizng me for being the Ignition Timing NAZI? :D :D

Jeff, I'm glad that you can use them.
I like the guy's hand pushing down on the piston (left side image), and then his hand hitting the piston (right side image).
They should have placed a big hammer in that hand! :D


I did a search to see if I could find a .gif file that would let me stop it @ 14* ATDC....... no such luck!
If you ever come across one, please post it somewhere.


Here's an Engine cut-a-way view thread that I started in May, 2010. Some good stuff here also.

It's amazing to see how many good images we can find on the Internet these days..... (some lousy ones also).


.
 
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Oooops......... thread Hy-Jacki in progress!

Jeff, that is excellent..... and yes, I'm a big 2 stroke piston port engine fan.


chambers.gif

The higher performance 2 stroke engine exhaust system works on a sonic wave principle, as you can see above.
At the correct RPM and load, and when the charge is just right, this increases the dynamic compression just as the piston port is closing.
This was called "being on the pipe"!
I don't know how accurate these guys are, but this is discussed here.

I rode Husqvarna for years after making the mistake of seeing Bruce Brown's film, "On Any Sunday"...... (1971 I believe).

images



Great .GIF file, Jeff..... I'm adding that one to my Engine Cut-A-Way view thread in the BOC forum. :cool:
 
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