Big Bart
Tow&Slow
I have the similar Kent Moore tach and time. What is not well documented on this site is how to use this style of meter from what I read prior to buying one. (Forgive me if wrong and just did not find the info.) There are multiple ways to use this style of meter to set timing (Per above.), when I bought a Tach and Time I thought there was only one way to hook up and use. But there several ways. (On both Tech-Time or Tach and Time, perhaps Rotunda too. Not sure as I have not seen one up close.) Remember the timing should be between 9.5 degrees BTD (lots of fans of this) and factory 8.5 degrees BTD at 2000 rpm. Also I learned the hard way, check timing when ever you rebuild the IP or just replace only the injectors. It does effect your timing.
Options on use -
1) If both the piezo pick up (Clamp for injector rail) and the crankshaft damper pick up both work on your meter, then the Tach and Time system will figure out you’re timing without a timing light. It will do an automatic 20 degree offset on the screen when selecting this timing option and with the engine running will share your timing. (Why 20 degrees? Because the pickup hole is not at TDC, rather 20 degrees off.) The Tach and Time meter calculates the crankshaft position, the injector pulse timing, adjusts for the offset, and displays your timing. (#1 injector is passenger side front.) If your timing bracket on your engine is loose, bent, damaged, this should not be used as you will likely get false readings. Also, if your crankshaft damper is bad/spun you need to replace it for either test. (Or your TDC mark may not be in the correct spot, so you will set the timing wrong.)) Turn off the engine (Many warn to not change the timing when running the engine like a gasser.), unloosen and move the pump a sliver (Dime width or 1-2 degrees.) Try again till you get it right. If you have to move the IP very much, I suggest loosening the injector lines on the pump to avoid bending/cracking.
2) If your piezo pickup works (But your damper pick up does not, or you have issues with the bracket on the engine.) you can use the piezo clamp with a timing light that has a timing advance feature. Put the inductive pickup of the timing light on the Tach and Time timing light inductive loop bar (Looks like the one above.) Set your timing light's advance to your desired setting. (Let's say we want factory 8.5 degrees BTDC, we set the timing light advance to 8.5 degrees. Figure on 9 if you cannot set for half a degree.) Start the engine, go to 2000 rpm, and you want to see the timing mark line up with the TDC mark. (Remember your timing light is advancing your strobe by 8.5 degrees, so at TDC, you are 8.5 degrees BTDC.) If your timing is off you can advance or retard (Your at 8.5 degrees.) the timing light to see how far your timing is off. Adjust the timing advance till the line matches up. If you cannot its because your timing is too advanced. Remember your timing light (At least mine) does not have the feature to retard the timing strobe, just advance the strobe.) So how do you calculate how far off you are. Let’s say when you set the timing light from 8.5 degrees to 5 degrees you’re now at TDC at 2000rpm. 8.5-5 = Means you are 3.5 degrees off. Let’s say you have to advance to 12.5 degrees BTC. 12.5-8.5 = 4 degrees off time. Shut down, turn the IP left or right accordingly and retest till you get the desired timing. In this scenario there is no need for a 20-degree offset since your timing light is showing the pulse in real time and you are using the TDC mark on your timing bracket. (Your damper probe hole is offset 20 degrees from TDC.) Some folks say certian timing lights do not work well with these induction bars. So do not assume the bar is bad, try a couple of timing lights to see which one works. I have a Snap on Light but it struggles a little on low RPM. (Perhaps its the meter or piezo clamp does not seem to matter, all works at 2,000 rpm.)
3) If your damper pickup works, your luminosity pick up works, and luminosity glow plug works. Then you can use the meter to determine the timing via the glow/flash of the exploding diesel in the head chamber. (Seen through the glass top of the special testing glow plug.) I do not have these parts so no pro here, have read your diesel octane has to be a consideration for the timing choosen.
4) Guessing here but if your luminosity pick up and luminosity glow plug work you could use the timing induction bar with a timing light to set the timing. I do not have the luminosity gear so just guessing but if the pickup is working, the meter is reading RPM, I would imagine it pulses the induction bar.
Now food for thought
1) From what I have seen on this site the Rotunda has a big Piezo clamp that goes on the bulge of the #1 injector. (Please confirm.) Guessing this was to make a more distinct/stronger reading. Tech-Time and Tach and Time both use a small one for the thin part of the injector line.
2) Now let’s blow your mind. You can actually put the small Piezo clamp on any injector line, you just have to set the "Offset" to the correct degree. So if your piezo does not work on injector one's line but will work on injector two's line then you just change the offset. (Your meter should have the offsets per cylinder in the manual.) But keep it simple and use on #1 when possible.
3) Is my piezo dead or working? Do the following to test, don’t assume its bad.
a) Check the connection and wiring. (Look good?) Does your RPM gauge on the meter work with engine running? If so, the piezo clamp is working. Another check is to hook up a timing light to the meter, start engine, does it flash. If so, your piezo clamp is working.
b) Check on a different injector line if not working. (Works now it’s not the piezo.)
c) Remove any dirt and paint off the injector line, clean the piezo clamp, and recheck. Getting an RPM signal, its working
d) Keep the piezo clamp as possible to the injector but do not put it on a bend. Can change the timing slightly.
e) Keep the piezo wire away from things that cause interference. (Alternator, regulator, battery, trailering wiring, etc.) May cause an issue or not to work.
4) Damper pick up. Dead or working? Test, move, and retest, don’t assume its bad.
a) Clean out the hole on the timing bracket on the truck. (Gun barrel brush or mops work good.) Lube the sides of the pickup to let it slide in and out without binding or sticking. You do want to have to yank on these to get them back out.
b) Put the pickup in the pickup hole on the bracket on the engine. It needs to be close enough to read, but not touch. Put a business card or larger feeler gauge between the pick up and the damper. (It appears you can push this all the way onto the dampener. That would damage the probe end.) Once you have the pickup in place remove the business card or feeler gauge.
c) Clean the marks on the timing bracket so you can see them. (Brake cleaner.)
d) Clean the marks on the dampener pully and mark with white paint. Paint pen, liquid paper, etc.)
e) Keep the wire away from your fan belts and moving components.
f) Keep the wire away from things that can electrically interfere. (Same as above.)
Is my meter dead?
a) Does it power up? Check wires and clamps.
My RPM gauge and my meter's or timing light's RPM gauge do not match. I would suggest using the meter's or timing lights RPM guage. My truck showed 650 rpm, but my meter and timing light said 550. I went with what the meter said, I am now happier with the idle and cold start. As you may know the dashboard guages are not known to be accurate.
I could not get my wrench over the bottom right IP bolt. So I did as others suggested. Bought a spare at the auto parts store, then ground down the closed end part till it fit between the IP and the bolt allowing access to the nut.
So the good news is if you buy a used diesel timing system, you have options if things are missing or broken. It will likely pay for itself after 1 or 2 uses. If the Gunson system works not sure it is worth investing double or triple into a Tach and Time or Tech-Time to find it does not work or fit your application. But if you can buy a new/un-used Tach and Time or Test-Time that is tested or returnable for under $200 then no harm no foul. Just note Tach and Time parts are no longer available from what I have read on this forum.
Options on use -
1) If both the piezo pick up (Clamp for injector rail) and the crankshaft damper pick up both work on your meter, then the Tach and Time system will figure out you’re timing without a timing light. It will do an automatic 20 degree offset on the screen when selecting this timing option and with the engine running will share your timing. (Why 20 degrees? Because the pickup hole is not at TDC, rather 20 degrees off.) The Tach and Time meter calculates the crankshaft position, the injector pulse timing, adjusts for the offset, and displays your timing. (#1 injector is passenger side front.) If your timing bracket on your engine is loose, bent, damaged, this should not be used as you will likely get false readings. Also, if your crankshaft damper is bad/spun you need to replace it for either test. (Or your TDC mark may not be in the correct spot, so you will set the timing wrong.)) Turn off the engine (Many warn to not change the timing when running the engine like a gasser.), unloosen and move the pump a sliver (Dime width or 1-2 degrees.) Try again till you get it right. If you have to move the IP very much, I suggest loosening the injector lines on the pump to avoid bending/cracking.
2) If your piezo pickup works (But your damper pick up does not, or you have issues with the bracket on the engine.) you can use the piezo clamp with a timing light that has a timing advance feature. Put the inductive pickup of the timing light on the Tach and Time timing light inductive loop bar (Looks like the one above.) Set your timing light's advance to your desired setting. (Let's say we want factory 8.5 degrees BTDC, we set the timing light advance to 8.5 degrees. Figure on 9 if you cannot set for half a degree.) Start the engine, go to 2000 rpm, and you want to see the timing mark line up with the TDC mark. (Remember your timing light is advancing your strobe by 8.5 degrees, so at TDC, you are 8.5 degrees BTDC.) If your timing is off you can advance or retard (Your at 8.5 degrees.) the timing light to see how far your timing is off. Adjust the timing advance till the line matches up. If you cannot its because your timing is too advanced. Remember your timing light (At least mine) does not have the feature to retard the timing strobe, just advance the strobe.) So how do you calculate how far off you are. Let’s say when you set the timing light from 8.5 degrees to 5 degrees you’re now at TDC at 2000rpm. 8.5-5 = Means you are 3.5 degrees off. Let’s say you have to advance to 12.5 degrees BTC. 12.5-8.5 = 4 degrees off time. Shut down, turn the IP left or right accordingly and retest till you get the desired timing. In this scenario there is no need for a 20-degree offset since your timing light is showing the pulse in real time and you are using the TDC mark on your timing bracket. (Your damper probe hole is offset 20 degrees from TDC.) Some folks say certian timing lights do not work well with these induction bars. So do not assume the bar is bad, try a couple of timing lights to see which one works. I have a Snap on Light but it struggles a little on low RPM. (Perhaps its the meter or piezo clamp does not seem to matter, all works at 2,000 rpm.)
3) If your damper pickup works, your luminosity pick up works, and luminosity glow plug works. Then you can use the meter to determine the timing via the glow/flash of the exploding diesel in the head chamber. (Seen through the glass top of the special testing glow plug.) I do not have these parts so no pro here, have read your diesel octane has to be a consideration for the timing choosen.
4) Guessing here but if your luminosity pick up and luminosity glow plug work you could use the timing induction bar with a timing light to set the timing. I do not have the luminosity gear so just guessing but if the pickup is working, the meter is reading RPM, I would imagine it pulses the induction bar.
Now food for thought
1) From what I have seen on this site the Rotunda has a big Piezo clamp that goes on the bulge of the #1 injector. (Please confirm.) Guessing this was to make a more distinct/stronger reading. Tech-Time and Tach and Time both use a small one for the thin part of the injector line.
2) Now let’s blow your mind. You can actually put the small Piezo clamp on any injector line, you just have to set the "Offset" to the correct degree. So if your piezo does not work on injector one's line but will work on injector two's line then you just change the offset. (Your meter should have the offsets per cylinder in the manual.) But keep it simple and use on #1 when possible.
3) Is my piezo dead or working? Do the following to test, don’t assume its bad.
a) Check the connection and wiring. (Look good?) Does your RPM gauge on the meter work with engine running? If so, the piezo clamp is working. Another check is to hook up a timing light to the meter, start engine, does it flash. If so, your piezo clamp is working.
b) Check on a different injector line if not working. (Works now it’s not the piezo.)
c) Remove any dirt and paint off the injector line, clean the piezo clamp, and recheck. Getting an RPM signal, its working
d) Keep the piezo clamp as possible to the injector but do not put it on a bend. Can change the timing slightly.
e) Keep the piezo wire away from things that cause interference. (Alternator, regulator, battery, trailering wiring, etc.) May cause an issue or not to work.
4) Damper pick up. Dead or working? Test, move, and retest, don’t assume its bad.
a) Clean out the hole on the timing bracket on the truck. (Gun barrel brush or mops work good.) Lube the sides of the pickup to let it slide in and out without binding or sticking. You do want to have to yank on these to get them back out.
b) Put the pickup in the pickup hole on the bracket on the engine. It needs to be close enough to read, but not touch. Put a business card or larger feeler gauge between the pick up and the damper. (It appears you can push this all the way onto the dampener. That would damage the probe end.) Once you have the pickup in place remove the business card or feeler gauge.
c) Clean the marks on the timing bracket so you can see them. (Brake cleaner.)
d) Clean the marks on the dampener pully and mark with white paint. Paint pen, liquid paper, etc.)
e) Keep the wire away from your fan belts and moving components.
f) Keep the wire away from things that can electrically interfere. (Same as above.)
Is my meter dead?
a) Does it power up? Check wires and clamps.
My RPM gauge and my meter's or timing light's RPM gauge do not match. I would suggest using the meter's or timing lights RPM guage. My truck showed 650 rpm, but my meter and timing light said 550. I went with what the meter said, I am now happier with the idle and cold start. As you may know the dashboard guages are not known to be accurate.
I could not get my wrench over the bottom right IP bolt. So I did as others suggested. Bought a spare at the auto parts store, then ground down the closed end part till it fit between the IP and the bolt allowing access to the nut.
So the good news is if you buy a used diesel timing system, you have options if things are missing or broken. It will likely pay for itself after 1 or 2 uses. If the Gunson system works not sure it is worth investing double or triple into a Tach and Time or Tech-Time to find it does not work or fit your application. But if you can buy a new/un-used Tach and Time or Test-Time that is tested or returnable for under $200 then no harm no foul. Just note Tach and Time parts are no longer available from what I have read on this forum.
