So I just got my timing light and ferret adapter. I suspect my truck is down on power (hard to say since she was weak when I got her); certainly getting bad fuel mileage. So, after watching some youtube videos I went and tried timing it to see where I stand. Near as I can tell, at 2000 RPM (after the engine was warmed up), I am seeing the timing mark right at the first bolt of the bracket at 0 degrees. Am I doing something wrong? I thought that retarded of timing would cause all sorts of issues/barely be able to run? As it is, she starts right up from cold with just a moment on the glow plugs and, while not exactly fast to get there, she doesn't have any issue cruising down the freeway at 70MPH.

I also am trying to track down sort of an idle knock noise so I went and cracked all the injectors (one at a time of course) suspecting that one of the injectors might be bad. Seems that the noise mostly all went away when I cracked the #3 injector and got much worse when I cracked the #4 or #6 injector (forgot now, I will try it again tomorrow). Does this make any sense to anyone? I am not completely sure on the noise yet, was getting kind of late so I sort of hurried that test.

 

yes.you want to twist the ip (with engine off) so that the timing mark,lines up with the 0 TDC mark on the timing plate,while your timing light (with built in advance) flashes when set at 8 BTDC (plus or minus two,whichever you prefer.)
engine up to operating temp.
piezo clamp on #1 or #4 cylinder lines.
converter box turned on.
engine rpm: 2,000
8 BTDC (+/-2)

 

Ok, so I think I did it right then.

How much of a performance impact would 8 degrees retarded cause?

 

I'm not sure it would even run 8 degrees retarded.

 

8 BTDC isn't retarded timing.since 6-10 BTDC is spec,this means retarded timing would be 5 or less.

edit,oh did you mean it's at 0 BTDC? i have no clue what it would run like there.a slug i suppose lol but who cares right? that's not where you want to keep it. you didn't buy timing equipment to see how bad it was.you bought it to set it properly.

 

What kind of confounds me though is that she starts quite easily, glow plug by pass being pressed for five seconds and fires off within the first crank or two. I didn't think it would be so easy with the timing off that badly.

 

The meter read '0' with the line on the first bolt. I meant that the timing is about eight degrees off the recommended 8.5.

 

what "meter" and what "bolt"? you started by saying your timing equipment was a timing light (it has built in advance correct?) and ferret box.
disregard any bolts you see and line up the line to O and set it per instructions.disregard how it starts.you want to make it run correctly.i don't think your crazy like you asked about lol but i think what your doing here,is not trusting in your timing equipment.if you don't trust in the equipment and use them as instructed,then im sorry but you probably just wasted a few hundred bucks.

clear your mind and start over.disregard how it starts,disregard how it runs,disregard any bolts or whatever it appears to be lined up with currently and disregard how it sounds right now.clear mind,then:
follow the instructions exactly in post #2 and see how she runs.

 

I mimicked some of the tutorials on timing and got the ferret box and innova 3568 timing light. The bolt I am referring to is the one in your diagram (but the line is not visible, going to try and clean the plate to clearly see the line in a couple of minutes). I was suspicious of the result because previous information that I had read implied that such severely retarded timing (6 degrees outside spec) would not run well at all.

One item I want to better understand is that knocking noise I am hearing / mentioned in the first post. I suspect that I have an injector that is opening too soon / before the others and it worries me that advancing the timing more could cause damage by increasing the knock on that cylinder. Any comment on that?

 

yeah that's a good question too.if your reading #1 cylinder line right now lets say,then try verifying the timing using the #4 line.
one other thing i forget to mention here,but no doubt you read already,is insuring the timing plate is cleaned up (engine degreaser/carb cleaner works quick and easy) but also make sure you sand off the paint for your piezo clamp too.
ideally you'll start with a fresh set of injectors with 100k miles or less on them.the bad part of this is,if the ip is getting tired then the back to spec pop pressures of the fresh sticks might cause that,to call uncle.so a fresh ip and injectors and then setting the timing all go hand in hand.just like tuning a gas engine.you don't change spark plug wires and leave the old plugs in or change the cap but leave a worn down rotor.
you could set the timing.see if the knock goes away.if not,try pouring in a gallon of mercon atf and drive the truck.see if the injector comes out of it.the injectors could be getting fouled up due to retarded timing and they might clean right up.

 

Yeah, last night I didn't clean the timing plate before warming up the engine and, between the time annoying the neighbors and not wanting to stick my hand so close to hot metal, decided to guesstimate it. I could see it was way off anyway. I just cleaned off the timing plate and the line is exactly where I expected it to be (got to love denatured alcohol for cleaning!).

I did sand the injector line on the #1 injector, I will try the #4 injector this morning also.

Part of the trouble I have is that I don't know how old the injectors or injector pump are. The truck has 166K miles on it and I am pretty sure the pump was replaced with a reman at some point as it has a sticker from a diesel supply shop on it. Injectors I have no idea on.

One more question I have though, the timing didn't seem to change much between ~650 RPM idle and 2000 RPM for testing. Is this normal?

 

Ok, I just checked the timing using both the #1 and #4 lines. The #1 cylinder was advanced 1 or 1.5 degrees more than #4, but they were both generally in the same ballpark. I also noticed that the truck is putting out a pretty decent amount of grayish (I think) smoke. The angle of the sun made it easy to notice.

In terms of the knocking, I used a mechanics stethoscope (yay! first time using a new tool) and found that putting the tip on the #7 and #8 injectors I could most clearly hear the knocking noise. On both it was pretty clear and consistent. Moving forward, I could hear it less and less until I could hear no knock on #1 & #2 and just barely make it out on #2 & #4. I Tried cracking the injector lines on both #7 & #8 and doing so on either made the noise diminish to barely audible (#7) or completely go away (#8). The opposite injector in both cases still had some noise though it seemed less pronounced. There is also some difference in the noise, one side is a bit louder and sharper (#7) while the other, while still very clear, isn't as loud or harsh sounding.

Any thoughts on the knocking?

I can do a video of the noise also, but I don't know if it would be very useful, it isn't a crazy loud knock.

 

And now I just put some a bunch of ATF into the fuel filter and ran it for a bit to hopefully get it into the pump / injectors (20 or 30 seconds of running).

 

Sounds retarded, mine is around the same, jumps between 0 and 5* or so. They seem to actually start alot easier when retarded. Since it jumped around so bad i didnt even bother changing the timing until i get a better pump.

 

Mine doesn't seem to be jumping around much. It does change right when the RPM changes, but it gets right back to where it was.