timing
- Thread starter 90idi4x4
- Start date
Wyreth
Certifiable Noob
9.5* BTDC is what I hear alot. Mine is rather happy at the 9.2* I called good enough.
icanfixall
Official GMM hand model
The factory setting is 8.5 plus or minus 2 degrees... Now we all know better than that for many reasons. Now a days the fuel is so poor compared to when these engines came out. So we like to bump it up to around 9.5 degrees before top dead center when useing the plus timing method. If your going to be useing the luminosity type timing method you will have to remove the number one glow plug and install a probe called the luminosity probe. Then the timeng is actually done off the combustion flash and the actual timing is in retarded degrees. Something like 1 1/5 to 2 1/5 degrees retarded. I'm no expert on doing that like of timing so check around before you just take my word for it. I think the lumi timing method is done at 1400 rpm where the pulse timing method I know is done at 2000 rpm.
Alright ill see what instructor is using to time it. He mentioned tonight about "the screw" u turn up for fuel in the pump is not all it takes to get it goin right. There is another one in the fuel inlet that adjust pressure. He said we will turn it an 1/8th turn to bump pressure up abit because i added the turbo and turn the fuel volume up. Has anyone ever done this??
Now you want to adjust, turn up the fuel. Well, unless you have an EGT (Exhaust Gas Tempurature Guage) your messing with something that will mess up your engine. But if you insist on doing it here's how.
On the IP gear tower, below where the oil spout is, is a cover held on by two (2) bolts, remove that cover, then you will see the IP drive gear, There is a dowel pin that drives the IP along with three (3) bolts that hold the IP to the gear, DO NOT loosen them. Now rotate the engine by hand, 15/16" socket on the bolt that holds the damper pulley on, rotate engine so the dowel is at 12 O'clock, with the cover off the IP the hole to adjust the fuel should be there, if not, rotate the engine one more turn, so the dowel is at 12 O'clock. Now you can stick a 5/32" hex key in and adjust the fuel, ONE OR TWO FLATS OF THE HEX IS PLENTY, USUALLY THREE FLATS IS MAXIMUM put both covers back on, use a little RTV on the front cover. Start engine, reving to WOT (Wide Open Throttle) should make the exhaust puff a cloud of smoke black, driving down the road with WOT should make a cloud of black smoke for about 100 feet. The pic below shows the IP driven end with dowel slot and the three bolts that hold the IP to the gear.
CAUTION You may have to rock the engine a little to insert the hex key. DO NOT LEAVE THE HEX KEY IN YOU CAN SHEAR IT OFF
On the IP gear tower, below where the oil spout is, is a cover held on by two (2) bolts, remove that cover, then you will see the IP drive gear, There is a dowel pin that drives the IP along with three (3) bolts that hold the IP to the gear, DO NOT loosen them. Now rotate the engine by hand, 15/16" socket on the bolt that holds the damper pulley on, rotate engine so the dowel is at 12 O'clock, with the cover off the IP the hole to adjust the fuel should be there, if not, rotate the engine one more turn, so the dowel is at 12 O'clock. Now you can stick a 5/32" hex key in and adjust the fuel, ONE OR TWO FLATS OF THE HEX IS PLENTY, USUALLY THREE FLATS IS MAXIMUM put both covers back on, use a little RTV on the front cover. Start engine, reving to WOT (Wide Open Throttle) should make the exhaust puff a cloud of smoke black, driving down the road with WOT should make a cloud of black smoke for about 100 feet. The pic below shows the IP driven end with dowel slot and the three bolts that hold the IP to the gear.
CAUTION You may have to rock the engine a little to insert the hex key. DO NOT LEAVE THE HEX KEY IN YOU CAN SHEAR IT OFF
Wyreth
Certifiable Noob
Sounds like you're talking about the Torque screw. That one adjusts the fuel delivery curve, not max fuel. Personally I wouldn't mess with that one.
Also, X2 on what Oldbull said. Adding fuel without a pyro, is a really quick way to burn down your engine.
Im sry i must have been misunderstood. I already turned my pump up when i added my turbo. I moved it 3 flats. I told my teacher this because we were tearing down the DB2 pumps. He told me that u can turn the screw up and it'll allow more fuel in because the rollers can travel farther but i need torn up my fuel pressure out of the pump. The screw for that is located inside the hydraulic head of the pump. Its the center fitting. Has anyone ever moved this screw before???
Black dawg
Registered User
That screw adjusts the pressure regulator, it will affect advance function more than anything. I have adjusted the screw, to get the advance correct, and if your truck runs good, I would leave it alone.
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This thread is fuzzy at best. There is no need to remove the gear access cover to get the max fuel screw in the right position. A simple mirror will allow one to look in the side of the pump while an assistant bars the engine over by hand until the screw comes into view. There is no screw for adjusting the "presure" of the pump if you are talking about the force applied to the injectors.
Black dawg
Registered User
with fuel rate already up, if you were to turn that screw ( the one in the inlet cone of the ip) in some and set timing to 9.5, it will be one rattly smokey ****.
They way he said it was "the faster the pump turns the less times the holes or lined up for injection so if we up the pressure more fuel will get through at higher RPMs" ill try to get a better explanation of it tonight. Its getting timed this afternoon at UNOH.
rockbender
Full Access Member
Let us know how it all turns out!
