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Crankshaft Timing Plate Question

How noticeable would it be if the crankshaft timing plate was installed backwards? I've been daily driving this motor for over a year now and it has been "OK" the only real issue has been getting the ignition timing and idle spot on. I've never taken the crank bolt off of this motor, however the more and more I look at the pic of the plate, are those not the markings that would be present on the balance sprocket side? or is this some form of modern art formed by heat static and oil .

If it where on backwards and somehow runnable for 20k miles what would be some of the symptoms to look for?

I even tried the TDC screwdriver test which seemed to be right on cams line up right as its peaking TDC

 

cspetros

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Jul 19, 2008
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Port Norfolk, VA
If memory serves me correctly, the plate is flat, and aligned via a side pin in the end of the crank. So, even if it were installed backwards, I think it would still give the same timing mark location.
 

cspetros

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Jul 19, 2008
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Port Norfolk, VA
Edit: Actually, I see what you are driving at. If the timing mark is not in line with the crank pin... like here:



Reversing the plate would definitely cause the timing mark to be off, at least according to this picture from the manual. To verify, I would check to see that the number 1 piston is at Top Dead Center when your crank timing marks are aligned. Look into the spark plug well with a light.

Strange...

 
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boostedinaz

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Apr 20, 2006
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4,085
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Scottsdale, AZ
I've only seen it go on backwards once and with in a few minutes it bent the valves in a brand new head. /ubbthreads/images/graemlins/banghead.gif From that day forward I ALWAYS check to make sure it is on correctly.

As mentioned the best way to make sure it's correct is to check that the #1 piston is at TDC when the plate is lined up. If it is then the plate is on correctly. If it's not then swap it around and double, triple check.
 

Very first time I ever did a timing job on my 1g, I put that on backwards. The car never fired lol. Bent the valves lol.
 

Very odd, So 2 thumbs up on bent valves with the plate on wrong. Assuming those where stock setups (CR/HG thickness) If not chime in. I'm almost wondering if my valves have been "kissing" my pistons this whole time. There has always been a clatter sound heard from in the car, I thought that was lifters, some of it was but I Upgraded those last Monday and the sound is still there minus the lifter tick lol. There is also Lots of low RPM knock, the car will stall out if i go anywhere in the range of the perfect idle. The ISC pegs to zero always, all that makes it near impossble for me to set base timing right, if anything its advanced to much. Ive been shifting it below 4k for so long I forgot what a real 4g63 is like

If the plate where on Backwards It would put the crank @ 3deg BTDC? I'm so worried right now I'll be tearing into it again monday to be 10000% sure. When I tried the TDC ScrewDriver trick it seemed like it could have been TDC within a 2-3 cam tooth range. I need to get that cover off yet again /ubbthreads/images/graemlins/banghead.gif I picked up some camshaft seals as a to go back in /ubbthreads/images/graemlins/smirk.gif
 

boostedinaz

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Apr 20, 2006
Messages
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Scottsdale, AZ
That was my buddies issue with his car. Had a real bad tick on a brand new long block and we figured it was lifters. When it didn't go away and the car had little or no power we starting looking for issues. After about a week of cursing, writing and deleting for sale adds, more cursing, we noticed the plate could go on either way and was on backwards. Took the head off and saw the damage.

When you are checking for TDC with the crank the plate should be dead nuts on when the screwdriver is at the top. There in pretty much no room wiggle room, it's either on TDC or not.
 

Yea, the more I check around the more I think its backwards, Good to know at least your friends car was driving. In front of me right now is a spare crank sprocket from my 10 year old "I'll build up a motor soon block" The little Pin that keys the crank pulley is exactly across from the crank keyway, In my pic is sure is not that way, it looks like its turned counter clockwise, the timing marks where all lined up in that pic (taken quite a while ago)
 
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Galantvr41062

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Aug 20, 2007
Messages
410
Location
plymouth, MN
If you never had the crank bolt out, there is no way for the plate to be on backwards, unless the motor has not ran sense you purchased the car/engine. Also the timing mark plate holds the timing belt onto the crank cog, thus why it has a tapper away from the timing belt. If it was on backwards it would tear up the timing belt in a hurry.

When setting your base timing the #4 plug wire can be more accurate, it only sees about 20% of the total spark and can be a more stable reading then the #1 plug wire.

~John
 
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Balance shaft removal was done by a previous owner /ubbthreads/images/graemlins/mad.gif, I overlooked it until recently seeing that it could be put on either way. the thing that sucks is, I overlooked actually checking when I put in the revised lifters. Started to browse the forums like the old days and one post said hey you might have got #^&@%$# again /ubbthreads/images/graemlins/rofl.gif I'll be tearing into it for sure Monday to be sure and pop in fresh cam seals.
 

PreskitVR4

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Jun 28, 2008
Messages
272
Location
Prescott, Northern AZ
i did this once, on my brand new wiesco/eagle motor. car WOULD NOT build boost. my only savior was the fact that i still had stock cams. 17k later when i tore the motor apart to freshen up for the race car, i found slight valve marks in the pistons. Dont let a 4G63 newb dress your motor.
 

She still builds boost fine but it seems to just be there, rather than adding the power it should, if I hold the throttle down while boosting there is decent power until about 4 k or so then it falls flat and the only way to make it feel right is to shift. you drove yours 17k that way you say, I'm around there too, was there always a sort of bad motor mount sound heard mainly from the interior almost like rod knock, but not as loud as that would be. any after market exhaust would be enough to drown out the noise I'm hearing. where your valves bent or just kissing the pistons? Stock C.R.? MLS or other thicker HG? I really hope its on backwards at this point it would solve just about all of my tuning woes. Every Mitsubishi seems to have a previous owner, Trusting there works seems near impossible esp if the are trying to sell in a rush. I'll get to the bottom of this tomorrow and update the post to reflect what i found as it may help others in the future.
 

PreskitVR4

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Joined
Jun 28, 2008
Messages
272
Location
Prescott, Northern AZ
I found my prob after only 18mi fourtunatly. Found it, fixed it, did a comp/leak down test, all was good. Didn't find the kissed pistons til 17k later. Super thin HG at the time, Wiesco HD 9:1
 
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The plate was on there correct, this must be early stages of rod bearing failure /ubbthreads/images/graemlins/bawling.gif
 
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