So I just aquired another complete 6.5 optimizer, but didnt have a timing tab.
Got another tab, now just need to set it in the correct position on the balancer.
All advice and insight is greatly appreciated.
Thanks in advance
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So I just aquired another complete 6.5 optimizer, but didnt have a timing tab.
Got another tab, now just need to set it in the correct position on the balancer.
All advice and insight is greatly appreciated.
Thanks in advance
If you have a electronic IP you won't need the tab as you time it with the correct scanner..
If using a manual IP, and you have a MT1480 timing machine you will need the tab..
You will need to remove the DS head and move the #1 piston to top dead center then adjust the tab to show tdc.
Getting actual TDC can be a tad tricky.
The piston can be at TDC in the bore, but the crank swings a few degrees as the rod articulates across while the piston is at TDC.
The most accurate method is to use a degree wheel fastened to the dampener (WITH HEAD OFF)
You need a flat piece of steel that you can bolt across the bore of #1 cylinder
The steel bar needs a hole in it and a bolt threaded into the hole so that the piston can't get all the way to the top. (Say 1/8th inch down in the hole)
You need a pointer bolted to the engine fashioned to indicate on the degree wheel.
Roll the engine in one direction until piston contacts your stop bolt and note the degree wheel reading with a little pencil mark on the wheel.
Now roll the engine the opposite direction until the piston hits he stop bolt and mark the degree wheel.
Actual TDC is 1/2 way between the two marks
When you start the process with the first mark adjust your degree wheel so your pointer is on a major mark (Say 10 degrees)
The stop method takes all the error out of the equation and gives you actual numbers and location of the crank.
NOW IF YOU DO NOT NEED TO TEAR THE ENGINE DOWN FOR OTHER WORK...
Secret....
Remove the Left hand valve cover (Fuel lines if they are on the engine)
Remove the front rocker arm set.
Fashion a little bracket that can bolt to the exhaust port on the number 1 cylinder or ??? and to an intake bolt.
YOU NEED YOUR BRACKET TO CROSS OVER ONE OF THE VALVES ON THE NUMBER 1 CYLINDER.
Your bracket will need a hole directly over one of the valve stems.
Install a bolt so you can jack one of the valves open a fair amount. (3/8 inch)
YOU ARE GOING TO USE THE VALVE AS YOUR STOP.
Do the same maneuver as described above with the stop bolt.
Same everything applies, except you don't need to pull the head.
Once you are done, re install the rockers and the cover.
Done deal
Once you have found both marks (on the wheel) adjust the balancer mark to the 1/2 way point between your two datum points.
Set your timing bracket so TDC lines up with the balancer mark.
Good idea to mark the timing cover so that the bracket can be replaced if need be and without the need to redo this procedure.
Takes longer to go through this here than it takes to do it..
GOOD LUCK
Have fun
Dang. I wish I had thought of that on my old engine. After it was together and in the car I realized there was no pointer on the timing cover. Could have done that in the car.Quote:
Originally Posted by Robyn
Using the valve for TDC locate is old school (sorry Robyn, but we are old). I use a leak-down tester to pressurize the cylinder (keeps the valve up), then a fork-type spring compressor (slips under the springs) that doesn't require head removal. Place a hose clamp or zip tie on the valve stem to allow an inch or less of travel and remove the air pressure. Any depth gage or contrivance can be used to locate the center of TDC, as Robyn described.
If you have to rotate the IP more than a tiny bit (1/16"+ at the scribe marks), be SURE to loosen and tighten the injector line nuts on the IP (relieves torque stress). If you don't, they will either loosen themselves or crack the lines, after a while.
That said, I've not used a "timing device" since the first few times, decades ago. Maybe good for a starting point, but I do better, and much faster, by ear with MFI Diesels.
Damn.... I hate being reminded that I'm old :D
Lotsa tricks to getting these diesels happy.
The EAR AND BUTT DYNO work swell.
A tad retarded and they smoke at idle and are hard to start.
Advance until the stack is clean and then advance a touch more.
Check the EGT to make sure they are within the safe zone.
Retarded timing builds heat in the exhaust.
A tad advanced will usually not hurt zip, but might mess with emissions a bit.
OH JUST AN FYI
YOU CAN RUN YOUR DIESEL WITH THE INTAKE OFF....BUTTTTTTTTTTTTTTT
BE SURE YOU DON'T HAVE ANYTHING LOOSE LAYING ABOUT..
LIKE RAGS :eek:
THEY CAN AND HAVE BEEN SUCKED DOWN AN OPEN INTAKE PORT. :eek:
A RAG WILL DESTROY THE ENGINE. BELIEVE ME... A LOCAL FELLA DID IT ON A NEW ENGINE AND IT BROKE THE BLOCK AND BENT THE ROD.
IF YOU ARE GOING TO RUN THE ENGINE WITH THE MANIFOLD OFF, MAKE SOME PORT COVERS FROM 1/8 INCH SCREEN WITH BOLT HOLES AND FASTEN THEM TO THE HEADS.
GM HAD A SPECIAL TOOL FOR THE JOB LISTED IN THE SERVICE MANUALS.
WITH THESE TOOLS IN PLACE YOU CAN DO THE TIMING AND ALL THAT AND THEN LOOSEN THE LINES AS MAVERICK MENTIONED ALL BEFORE YOU BOLT THE INTAKE ON.
BE SAFE
A dial indicator will tell you TDC but there are a few degrees of crank movement right at TDC that is very hard to discern with the dial indicator....
You are actually locating TDC of the crank throw...the piston will take care of itself.
The rod actually moves across TDC with little to no piston movement.
The hard stop method and then splitting the difference will put you right on the mark.
But actually the ear and butt dyno will gitterdone fine.
I have never owned a timing meter for a diesel.
The electronic injection can be a wickerbill without a tool.
I have marked the DS4 with a scribe line across the cover and then used the same cover and IP on a fresh block with all different internals and had it work fine.
As long as the ECM can adjust the timing to whats stored in memory all is well.
Kentmoore intake port cover tools
2 sets required
I know that there are programs for a laptop that will read the engine as it funtions and running. Has anyone ever used these progs? Mine is a 1995. Im using stock electronic pump so I guess the tab is a non factor.
Thanks yall
Here is the best bang for the buck
GMTDSCAN
http://leroydiesel.com/products/gmtd...tool-software/
In years past it was pretty much limited to a Tech tool (1, 1a or a tech2)
This software does the trick.
I do not own it myself, but have used it a few times.
Have fun.
Good info from everyone!
I usually set the MFI timing by ear....
Ditto! I once borrowed a Kent diesel timing tool and then discovered that my timing tab, too, had been removed. Didn't do me a bit of good to have a timing tool, then.Quote:
Originally Posted by More Power
I've always had good luck setting timing by ear and by the butt dyno.
Casey
I have a device that has a probe that threads into the #1 glow plug hole. It is an optical sensor that sees the combustion event. Some magic in the electronic box generates a high voltage current in a loop the size of a spark plug wire. Place the inductive pickup of a standard timing light on the loop and you have a way to check timing on MFI diesels. I don't use it often, but it works.
Yeah, got hosed by Leroy in the past on some parts, so that's a no go.. I know theres a guy in Europe somewhere that has a similar progQuote:
Originally Posted by Robyn
The guy in Europe is the one who wrote it. Leroy must be a dealer.
John Kennedy had a PC scan tool that works great. I have a beta version. I don't know what he is doing with it now.
Sorry to hear of the bad deal with Leroy.
I have traded with him few times and had no issue
This link takes you to the folks who made the software
http://www.enghmotors.com/tech/default.aspx