New Injectors Installed

Steve S. · July 27, 2009, 05:59:31 AM

I installed new injectors last weekend and finally went for my first extended motor. Good news and bad news. First the good. Taking out the old injectors and installing the new ones was alot easier than I thought it would be (thanks to Hank Recla's instructions). The hardest part was bending back the banjo and avoiding crimping the lines. (Hint - very slowly.) I didn't need the breaker bar to get the old ones out, but as Ron so aptly says, there is too much damn paint on these engines and I had a wrench in one hand and a vacuum in the other. Only addition to Hank's instruction would be that a toothbrush was handy for cleaning the threads in the engine block before installing the new injectors. The engine does have more power at lower RPM's, and the white smoke issues that I have but were lessened considerably. Now the bad - At certain rpm's, especially lower, the harmonic knocking that I have is worse, esp. 800-1000 (idle speed). It really smooths out at about 1800, and then gets a little knocky at 2200 and up. All I can figure is that the engine is running more powerfully and the valves are knocking more. Any ideas? I have new motor mounts, so it could be related to that, but not sure.

tonywright · July 27, 2009, 07:20:59 AM

Steve

Is the knocking under load or when revving in neutral?

Tony

prh77 · July 27, 2009, 08:38:46 AM

Where do I find Hank's instructions? I do not think the knocking is valve related, but is a function of pressure rise at combustion. When we did the injectors, we loosened the nuts at the injection pump, so the lines rotated out of the way.

Steve S. · July 27, 2009, 10:16:28 AM

Tony, prh77:

The knocking seems to be worst at idle in neutral. It continues when I put it in gear but is a little more distinct. I'm not sure which nuts you are referring to. Underneath at the pump itself?

Hank's notes are in the November 1999 tech notes. Ron had an addendum in Aug 2002. There is one change I would make. I believe the notes said use a 1 1/8 deep socket. A 1 1/16 deep socket works better.

tonywright · July 27, 2009, 10:20:40 AM

Steve, I think that there was a technical note on adjusting the valves every few hundred hours. Have you tried that?

Tony

Steve S. · July 27, 2009, 10:52:57 AM

No, not yet. I think that is my next step. Just need to get a replacement gasket. I believe there are detailed instruiction in the tech notes somewhere, so not too hard to do.

Stu Jackson · July 27, 2009, 11:45:59 AM

November 1999 Tech Notes Online

How'd I find it? Magic: I used Jon Schneider's Knowledgebase, and used CTRL F with the search word "injector."

prh77 · July 28, 2009, 05:38:22 AM

The nuts I am referring to are at the other end of the fuel injection lines at the pump. Loosen them and the lines swivel out of the way.

Steve S. · July 28, 2009, 05:59:10 AM

Good tip! That would have been good to know. What I ended up doing is loosening the little clamp bracket that secures the banjo lines together. But again, it sprayed too much of that gold paint everywhere and turned out to be more annoying than useful. Next time.

Ron Hill · July 28, 2009, 05:35:25 PM

Guys : Not to be a stickler on terminology, but the fuel lines from the injection pump to the injectors are call fuel lines".
The "banjo/s" is the in/out excess fuel connections between the injectors.

After installation of new injectors don't forget to put some soapy water in the injector well. Then run the engine. If you don't see bubbles, you've got a good seal. If you see bubbles you're loosing compression. A thought

Steve S. · August 18, 2009, 07:20:50 AM

Happy to report - no bubbles. But the knocking is driving me nuts. Still need to adjust the valves tho.

Ed Shankle · August 18, 2009, 10:10:19 AM

I plan on replacing the injectors this weekend or next.
Question: I've got the rigid lines banjo. Would I be better off using the "banjo body" that comes with each new injector and installing new fuel line hose to interconnect them? Or, just re-use the existing banjo with the rigid lines?
I'm thinking that if there is some subtle difference in that banjo body, I could be introducing a problem by re-using the old one on the new injectors.
Yes, I know I could be over thinking this, but it's the little things that always seem to get me.

thanks,
Ed

prh77 · August 18, 2009, 04:58:26 PM

Use the new banjos with new fuel line. New is the way to go.

Ron Hill · August 18, 2009, 05:30:42 PM

Ed : NO, use the same banjo with the ridged lines as long as you haven't bent those lines (and then straighten them) so there is a leak. The metal banjo connections are much easier to connect all in one than the added lines between separate banjos.

Just make sure that you use a new (crush) aluminum washer for the banjo and a new copper (crush) washer for each injector it'self.

Ed Shankle · August 24, 2009, 06:41:04 AM

I replaced the injectors this weekend, and thanks to Hank's and Ron's procedures as well as additional comments from others on the post, it went well. Took about 3 hrs, from laying out the tools to putting the last tool away. I move slowly, particularly with a task I haven't done before.
I do have a few steps to add to the process; at least what I had to do for my particular set up.
1. It would not have been possible to remove the injectors without moving the rigid fuel lines with compression nuts out of the way. Plus it just makes getting the banjo out easier, particularly if they have the rigid lines connecting them, as mine has. So I followed the suggestion to loosen the nuts at the other end of the fuel line, at the top of the fuel pump. Here's where I add a few new steps.
a. I could loosen the 2 outer nuts with an open end wrench, but the middle one is too close to the others to use the open end wrench. So I had to use the closed end of the wrench, by looping it over the compression nut on the injector end and traveling down the line to the pump end, and loosen the nut. but first, in order to clear the path down the line and to be able to swivel the lines,
b. I had to remove the rubber clamps that hold the 3 lines together, but
c. In order to get at those screws, I had to remove the air intake/filter housing.

2. Had to remove the valve cover in order to get the 1 1/16" deep well socket over the injector.

I did reuse the old banjo. Just cleaned up a bit underneath with some acetone, so the paint line wouldn't interfere with the setting of the new aluminum ring.
There you have it. Just a few more items to be ready for when you do the job.

Ed

PS M25XP engine