Timing on 7.3 w/old fuel system

[smolkin]

Much importance has been placed on timing with a meter on this forum. While I do not doubt it is better than "by ear", my question is, how much better? I'm running old injectors and a 6.9-spec IP that's got about 15K and 3 yrs on it. I timed it by ear when I put the IP on. It runs OK, mileage is a bit lower than I expected (around 15, 16). The same pump, on my '84 got 17-18 mpg. I haven't been able to find a shop down here that even owns a meter. In fact, just this past week I got this from Dixie Diesel (a reputable big-rig shop):

Ya wanna time that old thing with a meter. Ha! You can't do that, you just line up the factory marks and it's timed. Stop wasting my time with this $&*%!

I know the IP isn't quite right, but I was led to believe it shouldn't make that much difference. Is it worth it to keep trying to track down a meter? Also, I have 6.9 lines so no timing adapter. Thoughts?

 

[WhiskeyBottle2]

Timing

Much importance has been placed on timing with a meter on this forum. While I do not doubt it is better than "by ear", my question is, how much better? I'm running old injectors and a 6.9-spec IP that's got about 15K and 3 yrs on it. I timed it by ear when I put the IP on. It runs OK, mileage is a bit lower than I expected (around 15, 16). The same pump, on my '84 got 17-18 mpg. I haven't been able to find a shop down here that even owns a meter. In fact, just this past week I got this from Dixie Diesel (a reputable big-rig shop):


I know the IP isn't quite right, but I was led to believe it shouldn't make that much difference. Is it worth it to keep trying to track down a meter? Also, I have 6.9 lines so no timing adapter. Thoughts?

To set the timing, clean the damper and the magnetic pickup holder. Then install the magnetic pickup line connected to the SPX Kent-Moore J33300-A timing machine. This measures the engine’s rpm. Use the top skinny holder next to the damper. Then sand the number 4 injection line to bare metal and install the clamp. The cylinder numbers are marked on the intake manifold runners. The odd-numbered cylinders are on the left, the even ones are on the right. The low-number cylinders are toward the front. The wire has a ground and connects the machine to the clamp. This registers when the injection pump fires. Put the transmission in Park or neutral if a manual and rev the engine up to 2,000 rpm. An initial run will usually come up retarded, and it’ll sound like a big-block gas engine. If so, advance the engine by turning the pump counterclockwise (looking at it from the front bumper or turning the wrench toward the passenger fender). Do the timing change without the engine running and then test again. The reading should say 9.6 degree before top dead center (BTDC). The electrical connection closest to the firewall on the Stanadyne DB2 pump controls the timing advance and needs to be unplugged when timing the engine. The electrical connection closest to the radiator is the fuel shutoff. The firing order is written on the valve cover: 1,2,7,3,4,5,6, and 8.

But, for me I just advance my timing about a dimes and a half width. In otherwords, just when it starts to clatter I back of just a hair and I am good to go...don't forget to tighten the pump back up before you start the engine each time you adjust and don't forget to plug the timing advance back in...

 

[smolkin]

Well, yeah, but I can't find a Kent-Moore anywhere around here. I'm pretty good at ear-timing, I take my time and did it on both the trucks I've owned. I should clarify a bit and say, can I hope to get better than current performance if I time with a meter?

 

[WhiskeyBottle2]

Better Performance

Well, yeah, but I can't find a Kent-Moore anywhere around here. I'm pretty good at ear-timing, I take my time and did it on both the trucks I've owned. I should clarify a bit and say, can I hope to get better than current performance if I time with a meter?

Well that depends on a lot of factors...such as milage on the engine, any mods done, etc..but generally with a fairly new IP and injectors or rebuilt...Timing the engine using meters is better...but like I said, for me I trust my ear and how the truck runs after earballing it...If my ear is off a bit and truck runs lousy...I re-earball it until I'm happy...

 

[icanfixall]

And why would anyone give money to that ****** from dixie whatever it was... Thats a fool that will soon be out of customers.. Unless they have those that liked to be put down... Gees.... Timing by ear is just a guess at best.. Timing like ****** told you to do is silly. Once the pump has been changed from the original factory pump those marks mean nothing at all. They are a close starting point but thats all... Every pump thats rebuilt wil be internally timed differantly. So now how is that dixie ****** looking to you. I use a kent moore J33300-A meter and the pulse type timing method. It breaks down the timing to the 10th of a degree. Can't really do that by ear or by the timing lite method of timing. I had a great timing meter rental program that I offered to members here. Seems my meters got broken so its not happening at this time. I will be doing it again but I don't know when. You posted your mileage is down some. Do this... Make a center punch mark in the joint line between the injection pump and the gear housing. Now advance the pump and test drive it. Only move the pump about 1/32 inch at a time. Thats just about the thickness of a dime... Not the width of a dime either. If your mileage goes up leave it. If it goes down you can easily move it back to where it was. The two half circles just needs to be matched up to make one complete circle. Thats the center punch mark...

 

[smolkin]

I had a great timing meter rental program that I offered to members here. Seems my meters got broken so its not happening at this time. I will be doing it again but I don't know when. You posted your mileage is down some. Do this... Make a center punch mark in the joint line between the injection pump and the gear housing. Now advance the pump and test drive it. Only move the pump about 1/32 inch at a time. Thats just about the thickness of a dime... Not the width of a dime either. If your mileage goes up leave it. If it goes down you can easily move it back to where it was. The two half circles just needs to be matched up to make one complete circle. Thats the center punch mark...

The local diesel shops make their money off of the more common diesels, powerstrokes, cummins, duramaxes, and heavy-duty rigs. They don't care about IDIs any more, it''s just that simple. So it appears that they are obsolete, locally at least.

I'm kicking myself for not getting into your rental program when I could. I was reading the threads here about it and knew it was going on. I guess that if/when a meter rental program is up again, I'll try to get on board.

I just wasn't sure if a couple mpg lower is normal, considering it's the exact same IP, but on a 7.3 now. I haven't turned up the fuel or anything, and both the trucks ('84 and '90) had automatics (C6 and E40D respectively) and 2wd 4.10 gears. The '90 has quite a bit more get-up-and-go, though.

My plans include installing a pyro soon, and then I might turn it up a flat or two, but I still wanted to get the timing right first.

 

[redneckaggie]

Well im divided on this issue, On here I was told 1 degree of timing makes a huge difference in power and economy but when got one of icanfixalls meters my timing showed to be off by about 2 or 3 degrees, my overall mileage is up maybe one mpg, and power seems no different. While I definately agree that meter timing is best I think ear/power timing is more likely to be a close substitute than most on here will tell you if you are experienced and know how these engines are supposed to sound/respond

 

[dgr]

He can be an ****** as he chooses but what I don't understand is money is money. If he's got a shop rate, why would he care if he's working on a Peugot?

I timed my original pump with a Ferret. I timed my replacement pump with a Ferret. Neither of them had/have the timing marks lined up. The old pump was advanced over a dime thickness and the replacement is retarded over a dime thickness. I can say that the performance on the old pump was definitely improved when I increased the advance and it wasn't even on the timing marks to begin with. So ****** is wrong.

 

[chris142]

I'm also pretty late to the IDI party so I missed the timing light boat too. No Diesel shops or injector shops within 150 miles of me know anything about these older engines. I too was told to "just line it up" by more than just one shop.

I called one larger injector shop in the L.A. area about rebuilding my injectors and they told me to wait till I got a Check Engine light before I messed with those. I tried explaining to the English as a 2nd language guy that my truck was not electronic and it does not have a CK ENG light but he didn't understand. I have played with the timing some. I advanced it about a dimes width and it was better so I moved it another Dimes width and it ran great! But it sounded "Loud" for lack of better terminology so I backed it back down to my first spot and left it there.

My MPG is dismal at best.

So I too have no idea where my timing is and have no way of finding out

 

[riotwarrior]

Meter timing best...plain and simple...ear timing...well...ok, truck runs...could be better could be worse maybe even damage occurring and you would not know...

JM2CW..

AND GARY,,,it's a 1/2 DIMES thickness not width....