After changing injectors

Selahdoor

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What are the biggest differences that you guys have seen after you have changed your injectors?

My injectors are tired. Engine is loping. It seems that is probably because the injectors are not popping all at the same pressure any more.

I replaced the fuel filter. Filled the new one with ATF. Ran it until it was clear that the atf had made it all the way through into the cylinders... Let it sit for 24 hours, then ran to the post office.

Major difference! She rolls coal now. Only a little bit, and only if I really put my foot into it. Runs WAY smoother!

But I am not satisfied with that. I have already bought a set of injectors from Russ. I am going to be replacing the old ones in the next couple of days.

Just curious what kind of differences all yall have seen when you have replaced your injectors with a good quality set?

For instance, did you have to turn the IP back a bit? Did you use more or less fuel? Etc...
 

captain720

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If your investing injectors and ip and timing a pyro isn't that much more of an investment and totally worth it
 

Big Bart

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What are the biggest differences that you guys have seen after you have changed your injectors?

My injectors are tired. Engine is loping. It seems that is probably because the injectors are not popping all at the same pressure any more.

I replaced the fuel filter. Filled the new one with ATF. Ran it until it was clear that the atf had made it all the way through into the cylinders... Let it sit for 24 hours, then ran to the post office.

Major difference! She rolls coal now. Only a little bit, and only if I really put my foot into it. Runs WAY smoother!

But I am not satisfied with that. I have already bought a set of injectors from Russ. I am going to be replacing the old ones in the next couple of days.

Just curious what kind of differences all yall have seen when you have replaced your injectors with a good quality set?

For instance, did you have to turn the IP back a bit? Did you use more or less fuel? Etc...
My truck idled smoother but started running hot when towing. I did not check the timing but should have when I put them in. (Just ran out of time that weekend as my damper probe was not working.)

Once I set the timing (It was off.)
1) Truck ran cool again.
2) Idled smoother.
3) Had a little more power.
4) I could not hear the louder clatter on cold starts.

Changing the injectors improved the idle.
Changing the timing did even more. More power, ran cooler, ther cold starts, etc.

You need to do both, to do it right.
 

Selahdoor

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Thank you.

Did you have to set the timing up or down?
 

Big Bart

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Thank you.

Did you have to set the timing up or down?
Selahdoor I wish I could recall if my timing became advanced or retarded after putting in the injectors. As I recall I was moving the pump to the passenger side thus advancing it, but not 100% sure. Not sure it would matter anyhow, because I did not look at the timing before changing the injectors to know if it was on or close prior. Thus how much it changed overall.

As you likely have read the IP pump pressure and the injector pop pressure both partially determine the timing. So as they wear they effect the timing.

So if you have not bought one, I highly encourage you to buy a timing meter of some type or go meet up with a member who does if you do not already have one.(Tech section has a list of volunteers.) Many have recently bought the DTI Tech Time on eBay for ~$200. ($450 new from DTI.) Others bought early on when Snap On, Ferret, Ford, Kent Moore and others were still available new. I am a competent mechanic and I know I would not be able to set my truck at 8.5* by ear. Yes you can get close by test driving it over and over at this or that IP setting. My point is you will hunt for a place you like it but never know if you are within 2-5* of spec. I can say with confidence anyone with a IDI who buys one, will not regret buying one.
 

TNBrett

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Ditto on the timing meter. It's definitely the best $200 you can spend on your truck. Look at it this way, it's basically one fill up at today's fuel prices. I also get that is easy to spend other people's money for them. I would gladly help you get your timing set right if I were closer, so hopefully someone near you can help you out.
 

Selahdoor

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The way things have gotten, I can't afford a cup of coffee. Let alone what is needed to set the timing.

No one in this area is offering. I've looked.

If I could afford the setup, I'd buy it, learn how to use it, and then I would be the one offering.

I set the timing on the IP by hunch. It has been running really well. A little white smoke on startup. VERY little. A little black smoke if I put my foot into it. VERY little, and I have to really stomp on it. Puffs a little then goes clear again, even if I keep my foot into it.

Plenty of power for climbing the hills.

15 miles per gallon.

I have been pretty happy with it. So I suppose after I change the injectors, I'll just be setting the timing by hunch again. I was just hoping to have a bit of information before hand if people had to set their timing up, or down...

I was really hoping for first hand information, not discussion of whys and maybes, and opinions. LOL It's ALL good. Just that the info would be more helpful right now, when I am about to start replacing them.
 

The_Josh_Bear

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Well mechanically you should need to advance the timing. I hope you have a good IP on there if you're doing new sticks. Cause new sticks can make whatever issues your IP has, worse, which you probably know.

So the loose math is: worn out injectors pop at 1400psi(or whatever) and brand-spankin-new injectors pop at 1800psi or greater. It will take the IP a tiny bit more time to generate that extra PSI, and since it's a rotary pump that's an extra couple degrees of rotation towards TDC before the injector pops. New sticks means advance the timing. :Thumbs Up
 
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Selahdoor

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Well, I got em swapped.

I expected it to take a long time starting again. Was pleasantly surprised by how quickly it started up.

Ran smoothly. No waiting three minutes or more with the lope slowly getting less, as cylinders started catching up. It almost immediately ran fine on all cylinders.

I think the old poppers were in worse shape than I imagined.

Seems to run fine, as-is. I'll drive it soon, and then I'll have an idea whether I need to change the timing or not.

So far, the timing has been pretty much just where I had a gut feeling it should be.

And it didn't run like it was starving or anything, after swapping the injectors.

I'll put a good drive on her tomorrow.

Need to change the brake switch first, though. LOL Don't want to chance getting a ticket.

Thanks everyone!
 

Big Bart

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Glad it was a uneventful job. I here you you about the meter. The second best way is how you are doing it.

One clue for me was how there was significantly more clatter at start up with the IP advance on. When my timing was off I did not notice a difference. When the timing was on it was very noticeable. Perhaps that will help out.
 
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