Help! I'm throughly confused about pump timing.

[chris142]

I have been reading threads about pump timing. I read about a thing that replaces a glow plug and another tool that goes into the hole down by the crank pully.


So I stepped up onto the Snap-On truck and bought a "Diesel pulse adapter".

This thing----> http://buy1.snapon.com/catalog/tools.asp?tool=all&Group_ID=675494&store=snapon-store

It does not have the thing that goes into the hole above the pully. It has no directions in the box or on the unit. So I spent a while looking at it and figured that the clamp on thing must go on cyl#1 injector line and the other leads goes to ground. I then put my dial back timing lights clamp on pickup on the loop that comes out of the Pulse adapter.

I then let the truck warm up and checked the timing. @ idle it's @ 12btdc. Revved up to 2000rpm it's @5btdc.

In some threads you folks talk about setting the timing to 0 which = 8.5btdc. And in other threads I read about setting it @ 8.5.-9.0 BTDC.

Then I read about testing the Cetane rating of the fuel as well as setting the timing to your elevation.

So I'm completly confused. Do I set it @0 which is 8.5 somehow? Or 8.5@ 2000 rpm? And why don't I have the probe for the crank pully?

I'm @ 3100 ft if that helps.

Would somebody explain where the timing should be set for best Power and MPG with the tool I have?

Thanks.

 

[Trying my best]

8.5 at 2000

 

[Trying my best]

From what I gather, that thing you plug in your glow plug is a different animal, I have never used it. I have the one like yours, but its made by a different company.

 

[chris142]

8.5 at 2000

Ok cool. I just read another thread that talked about unplugging the timing advance. Do I need to do that too? Or just advance it some more ,tighten the pump down, start it and see where it's at?

 

[Trying my best]

Again, I'm kinda a rookie, but from what I understand, when you go to 2000 rpm, that takes the idle advance out of the equation. Someone more qualified might tell me if I'm wrong.

When I time mine, I don't unplug the timing advance, I just advance it, then check then repeat.

 

[chris142]

Ok so I was doing it right.......Kinda anyway. I wonder how much difference 3 degrees makes? When I got the truck it was a gutles **** so I just cranked the pump over and tightened it down. I'm happy with the way it runs now but I was worried about causing engine damage from it being too advanced so I bought the tool.

I probly paid too much but atleast now I know where it's set. Better than melted pistons.

 

[Trying my best]

That's what I did too

 

[icanfixall]

Please listen to what I can tell you and others. What you bought is the pulse type timing method. The injecter line must be sanded clean to metal or the pickup wont do a good job. That loop is where your timing lite connects to just like you do when timing a gasser engine with that timing lite cmalp connecting to the spark plug cable. So now we have that setteled. Warm up the engine and rev to 2000 rpm. Shoot the lite at the dampner tab. See that the lite shows the fat tube location is where the dampner line is. Thats top dead center. At 2000 rpm you need to adjust the timing lite for the degrees you want. So you preset the lite to be lets say 9.5 degrees before top dead center. Start, rev up 2000 rpm and shoot the lite. Hopefully you will see the lines match up... If not shut down and move the pump the direction you need. To advance the pump you turen it towards the passenger fender.. Never try to adjust the timing when the engine is running.
Now about the glow plug hole and the tool need for that and the cetane reading.. None of that is used because thats the luminosity type timing. Its done at 1400 rpm and the combustion flash fires the lumi probe and you need to know what the fuel cetane reading is. Its also done in AFTER top dead center readings.
When I time any idi I do it cold but... I remove the back wire on the top of the injection pump. Thats the electrical internal advance circut. Only reason I do it cold is I hate working on a hot engine. We live and learn... Mel taught me that idea back in 09 at the ralley....

 

[Trying my best]

Yea....what he said.

 

[riotwarrior]

Just a small tip to add for you as Gary has it nailed ON THE HEAD! Take a quick look here as Gary has often spoke of a center punch mark PRIOR to making adjustments...

http://www.oilburners.net/forums/showthread.php?59907-IP-Adjustment-for-timing-purposes&highlight=

Just a good pictutorial for the adjustments your about to embark on.

 

[icanfixall]

Just a small tip to add for you as Gary has it nailed ON THE HEAD! Take a quick look here as Gary has often spoke of a center punch mark PRIOR to making adjustments...

http://www.oilburners.net/forums/showthread.php?59907-IP-Adjustment-for-timing-purposes&highlight=

Just a good pictutorial for the adjustments your about to embark on.

Good point Al pun intended... This is something Mel at the 2009 rally taught me about doing timing. He told me what I have done in my choosen carieer industry. Make a whitness mark before moving or removing anything. Some of the 12 stage pumps we repaired would have a string of center punch marks at every housing joint. Some even had numbers punched into the flanges so we knew where each part went ...

 

[chris142]

Today I got a chance to move the pump a little more. I had to really fight it to get it to move! I don't seem to have a place on the pump to put a 3/4 wrench for leverage.I tightened it up and now it's @7*BTDC@2000 rpm.

Honestly I think it ran better @5*BTDC. I'm going to drive it a few days to confirm this. Maybe it's my 3100ft elevation or maybe the Barometric pressure was different today? It seemed to rev more "freely" @5. Now it seems like it does not want to rev.

 

[Trying my best]

Linkage issue?

 

[chris142]

Linkage issue?

Didn't touch it. I just loosened the 3 mounting nuts, pried the pump over about .020 and tightened it back down.

 

[RLDSL]

Today I got a chance to move the pump a little more. I had to really fight it to get it to move! I don't seem to have a place on the pump to put a 3/4 wrench for leverage.I tightened it up and now it's @7*BTDC@2000 rpm.

Honestly I think it ran better @5*BTDC. I'm going to drive it a few days to confirm this. Maybe it's my 3100ft elevation or maybe the Barometric pressure was different today? It seemed to rev more "freely" @5. Now it seems like it does not want to rev.

With the new fuel ideally 9.7 deg basically puts your engine performance right back where 8.5 deg did on the old high sulfur fuel. *.5 deg on the new ULSD would be considered retarded timing due to the difference in the burn rate of the new fuel, you would have poor performance and fuel mileage, especially considering your altitude which would be approaching the point of high altitude settings, which would mean increasing timing a tad more to compensate for thinner air.
At 5 deg that thing should run like total crap and inhale fuel like a fat gal with a box full of bon -bons at a boo hoo chick flick