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timing question

capemaydiamond

Contributing Member
I am ready to set timing on my rebuilt 454 tbi reverse rotation motor. What is the best way to do this being its a reverse rotation motor? I understand I have to put the ecm in base timing mode, just not sure of the correct way to read the tab.
 
if you have the correct tab, it "reads" just like a LH engine would....check its advance function before you start to see what you have would be my suggestion. (You can also assess the 'correctness' of the tab by inspection - its easy to get confused unless you make a drawing/sketch.)

If it turns out to be a LH tab, I'd keep the tab and get a timing tape....you read the timing tape using the "0" on the pointer as the reference line...
 
Ok my engine builder marked zero for me on the tab but when I was painting the motor I removed the tape and I am not sure where to put it back on. Do I line up zero on the tape with the notch in balancer? Also I was recommended to set base timing at 12 degrees. Should it be set at 12 retarded or advanced because of the reverse rotation?
 
As far as the timing tape goes, yes, the line on the balance for TDC is aligned with ZERO on the timing tape.....and wrap the tape "backwards" if the directions aren't explicit for engine rotation.

if you are talking about a piece of tape on the timing tab showing zero, better off doing something more permanent....find TDC on #1, using a stop, and then mark the tab to align with the balncer's mark.

!2 is a little advanced but could be driven by many factors, if it came from the builder, use it. If the timing tape is used, the advance is read directly off the value under the tab's ZERO line with a standard timing light....if you have an advancing timing light, most say turn the knob until the ZERO lines overlap and read advance off of the knob....

The final option is to use reverse rotation timing tab....usually, the timing tape is the much more economical option.
 
I forgot about the other option....just scribe the balancer - twice. first mark is for initial timing and the other mark is for full advance.

Works well assuming the advance mechanism works properly...all you need to do is use the arc length formula and convert degrees to radians....layout the lines on a piece of paper and transfer them to the balancer and then mark them (I usually use whiteout).
 
Mark, I consider myself a knowledgeable guy but I have no idea what you are talking about. Man I wish you were in Cape may nj. I'm gonna try the tape in the morning after prayer and I really appreciate your help.
 
Well Mark I did what you told me with the tape and it worked like a charm. Thank you. The motor ran like a top and as we were cruising at 3000 rpm we started to hear a loud banging from the transmission area so we throttled down and put it in neutral but the noise stayed. It sounded as if someone was banging a hammer on the bellhousing. And all of a sudden something jammed and stalled the motor. I pulled the starter and was able to turn the motor by the flywheel so I think the motor did not seize but something is still jammed in there. While I turned the flywheel slowly could hear pieces tumbling downward and it would jam at certain spots. Can it possibly be the damper plate with these symptoms? Boy I hope it isn't something with the motor.
 
Glad the timing issue is resolved...and mongo bummer on the stall out.

I'd suspect the damper .... hopefully its no more than a spring that failed. If you can get the inspection plate off, you can usually examine the pieces and figure out what they were (inspection plate is usually bolted to the flywheel cover [bellhousing] at the bottom - aft of the oil pan). Checking your parts manual's breakdown should give you an idea how many fasteners are used and their relative location....

If it turns out to be the damper plate, its not hard to do unless you access is limited....and you may wanna consider the other engine's damper plate, too, as a winter project...
 
Thanks Mark I'm gonna pull the trans Saturday. This really sucks but I've been doing this long enough to know it's part of boating and am not ready to throw in the towel.
 
I'm coming in rather late on this one, so bear with me if I'm being redundant.

You probably know that the timing decal must be correct for the diameter of the harmonic balancer.

If the machinist marked #1 TDC using the Positive Piston Stop method, I'd sure want to use his marking.


The beauty of the decal, or better yet having the balancer degreed, is that you will be able to check the progressive and TA while using a standard timing light..... (real degrees in real time).


Good luck to you.

.
 
Well it isn't the transmission. The motor looks like it broke a connecting rod or something of the sort. Engine binds up, can't turn more than a long or two. Worst part about it is the builder says he won't warranty it and treated me badly over the phone. I am disputing the charge with my credit card company but I have a really bad feeling about this one.
 
good the gear is ok...you didn't mention the damper plate...???

and mongo bummer on the attitude received....that really sucks....and the court based solution isn't any better...hope the credit card co helps out...

may wanna consider a knowledgeable third party oversee the teardown/inspections...
 
The damper plate and trans are fine just the brand new motor is screwed. Credit card company is backing me and I have talked to a lawyer. Also gonna have that third party document what broke. Thank you so much for all the advise.
 
I pulled the motor Saturday. The number two connecting rod cap blew through the side of the pan. It's ugly. Either the bolts snapped or they were never tightened.
 
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