Does anybody know the IP advance curve throughout the rpm range plus the volume it should pump? I am just curious to know, as I think I will explore some bosch stuff and try to mount something more err better Just curious to know, as there are always options to think about and mainly to save for

 

Jan.... To much man...

You cant directly compare DB2 pumps with any other.... The rest are sleeve/helix metered, these are inlet metered... The rate of injection is totally different.. Its why IDI's dont like advance like other diesels do...

 

I'm just going to put this out there and say that the timing varies with RPM, load, and throttle position.
It's a 3-factor curve that would need to be graphed, but I don't know of any such graphs.

If you have a P-pump, it pretty much doesn't do advance at all. It just sort of works, because of how the plunger timing changes with fueling.

 

The more I learn how it works the more I hate it, I do not think it is a good design at all. The only think maybe why they used it was to fit it in the middle of the V, Bosch or Lucas pumps run forever without touching. I think I need to save for one of your pumps, no matter what I do with the timing, I just dont feel it is to the potential of the engine. It is 7 litre engine for heaven sake, even passing semi is a quest on country road.

If I play with the fuel screw, it does affect only the wot right? Well it does not give any sense to play with it then in my case because anything over 3/4 of the throtle does not do anything, in fact it is worse than backing up a bit. The best way how to work with throtle in my case is as it speeds up just to give it more and more throtle, steping on it actually slows it. Should it work like that?

 

1. The engine is not to its full potential, you need a turbo.
2. You're timing is off, I'm pretty sure you are a bit retarded, these guys will verify. Have you adjusted the timing at all? If not, advance it a dime and see how it feels.

 

Yes.
Double yes.
Honestly, time it by ear by advancing it until it seems to clatter more and have less power than the previous adjustment, then move it slightly more retarded. Not perfect, but should work much better than now.

 

Yes I do have tried different timing and it makes no change to the throtle behavior. I am not a kind that cryes without even opening the hood. Owning a diesels for 20 years, always working myself on them.

And yes I do not have a turbo, but I do not want to admit it was designed to be a **** dog. I can beat it with 1980 1.6D VW Golf also NA and that **** has only 50hp at most when new.. Weights a ton, so 2.5 the weight is the weight of my truck, so the hp ratio is in trucks favor. I will get a turbo on it, but after I rering the engine, as the IH ring gap is crap nonsense since new. I do understand it is not race engine, but really there are NA engines half the displacement that would move it at least the same pace.

I need RD pump, please Santa Claus bring one to me

 

I am sorry Rob, but I already tried everything, no improvement in performance. Yes it clatters A LOT when cold, almost afraid to hurt the internals, once it warms up runs very quiet, smooth, no smoke at all. Cold starts without smoke. I know how the diesel should clatter, and how to set timing by ear, ask Jonathan F384 guy how his Jetta performed after the timing belt change and my adjustment. I do understand it is slow when hauling heavy load, but empty it should move decent, that is the 6.9 displacement right?

All fuel lines checked, no blockage anywhere. It is the IP I am 100 percent sure. I will try to swap the spare 7,3 pump I have just to see if it makes any difference.

 

OK so u pinched me to the ribs with the timing, I adjusted it now I am all the way to the left facing engine, more I would have to skip a tooth. I try it, the only thing I fear is to be far advanced, remember Justin being 17 degrees?

 

Well I do have to apologize Rob and Plumcrazy 7. I advanced it all the way to the end of the holes and the truck doubled the power, even spins the tires on first and second if u step on it. Wow. I think I am spoiled with EU diesels, which run smooth, not that kind of the clatter the US iron does. But I still feel that there is something wrong with the IP as it should not be all the way to one side, or somebody took the gear off and it is misaligned a tooth. Have to investigate. However now it is not that quiet while driving, the marks are misaligned by 5-6mm. No way this would work on pumps we have here.

But I apologize for being rude, I am a person that can admit that I was wrong.

 

As they say, especially with these engines, "timing is everything".

Does sound like you may be off a tooth....

 

Something that I just figured out week ago, that I've never read about on these forums is that if your return lines are too small or your pump bypasses a lot of fuel, you'll have terrible power pretty much all the time but especially at low RPM and high.

What happened is that my return line system is the 6.9 style, engine is 7.3. But I'd deleted the stock return from the IP and it dumped into the actual T's on the drivers side. Anyway that line was temporarily made outta clear hose and popped off while driving. They she drove like a champ!!
So after that I rigged a nice big 1/4" ID line straight from IP to the main return line, and she runs like she should! Ugh, finally after forever of messing around.

So if your IP return line is going through the T's of the return system, consider upgrading that part and see how she runs.

Hope that helps,
Joshua

P.S. My IP also had to be advanced an amazing amount, until the return line thing was fixed. Then it was too advanced, but honestly not by a whole lot. Maybe 2mm.

 

Yup. What you ended up doing is increasing the housing pressure, which retards the engine timing. These pumps are all about pressures and pressure-differentials, so keeping the right return lines is crucial.

edit:
Also, old pumps tend to have timing issues. It's just the nature of the beast. Compensate as best you can, until you can replace it.

 

Absolutely. My pump is a bargain-basement Pensacola Diesel rebuild, but my power got /worse/ after quality typ4/Russ pop-tested brand-new old-stock injectors, because of this housing pressure issue.
Once I added the full-sized return line, whole new ball game and best power my pickup has ever had!

 

I missed this post earlier.
Your pump advance is worn out. It doesn't have the same advance 'range' it had, so when you advanced it, the lower end became too advanced.
What I would do at this point is adjust the light-load advance cam. A 7/32 allen wrench will loosen the screw in it, at which point you can rotate it freely.
First position to try is rotating it such that at idle it's /just/ before it hits the cam portion. So when you move the throttle at all, it starts going up on the cam.
If that helps, move it further until it 'feels' better.
The sooner that cam engages, the lower RPM the retard kicks in, and the less clatter. Move it the other way, such that the cam is 'delayed', and you'll have more clatter down low and at idle.

Fortunately, it's easy to mess with and adjust. You can even do it with the engine running.