New injectors arrived. Advice?

Brian VT

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I got new injectors from one of the recommended rebuilders here.

I read the Tech. Article here on Fuel Injection Servicing. Very good info. Thank you.

That article includes removing the injection pump. I'm not replacing the pump.
Will I need to mess with the pump at all if I'm just replacing the injectors or will I just be removing lines from it? Should I be looking to buy seals to replace for those lines to the pump before I dig into this?

Any other tips/tricks appreciated.
 

Nero

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The lines are a compression fitting, so as soon as they are tight, so long as they aren't damaged they won't leak.
I usually will use a small bore brush with a rag to clean the injector bores, it gives the sealing surface for the crush washers a nice place to seat.
I also would get a fuel return line kit, some auto parts stores call them an injector install kit.
 

gandalf

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You don't necessarily need to remove the IP when you replace the injectors. You might, however, need to loosen the injector lines at the IP so those lines can move out of the way. Whatever you do, don't bend the injector lines. Also, if you need to clean the bores a 12 gauge bore brush seems to work quite well. When you pull the old injectors be absolutely sure that the copper washer comes out too.
 

Brian VT

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Thanks.
So it sounds like I don't have to mess with the IP until I time it after installing the new injectors.

A new fuel return line kit was included with the new injectors.
When I bought the truck it, supposedly, had a "new fuel system" and the return lines do look new.
So I may not bother cutting/installing new return lines or using the new caps.

I'm replacing the injectors because the truck smokes a lot until it warms up and I don't know what they bought for injectors. Many here seem to suggest that cheap replacement injectors are often a problem so I'm starting over with known-good injectors as a baseline to try to fix this.

I like the idea of using a 12 ga. brush to clean the bores but am nervous about getting crap down the holes?
 

Scotty4

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The reason there is mention of the IP removal is most likely to service or replace it with the injectors. It is not uncommon to have IP issues after new injectors due to the higher pop pressure of the new injectors and the worn out IP.
 

Brian VT

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Hopefully the IP is ok. That would be a big hit. How will I know if my IP is bad?

Right now I'm hoping I have 1 or 2 bad injectors that are causing the smoke until they come up to operating temp. (the smoke goes away once the coolant temp. gets to @ 150 deg.).

I hope I'm taking the right route to solving the problem.
 
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gandalf

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...

I like the idea of using a 12 ga. brush to clean the bores but am nervous about getting crap down the holes?

You'll have to disconnect the return lines from each injector when you replace it. When you re-use the return lines there is every possibility that there will be a leak. If the lines are old they will have hardened a bit, and be more difficult to reseal. OTOH, they are easy enough to replace if they do leak. It's just time and effort and frustration. If/when you do replace the return lines be sure to cut them to the proper length. There should be NO curve between injectors down either side. A curve in those short spaces puts undue lateral pressure on the injector nipples where the lines connect, making them harder to seal. They seal much better if the line goes on absolutely straight. The longer lines will have curve by definition.

Before you pull an injector you might want to vacuum around the area, and wipe it down, and vacuum again. I suggest you do the vacuuming when your wife isn't home. She may object to your using her vacuum of your greasy engine.
 

IDIBRONCO

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The reason there is mention of the IP removal is most likely to service or replace it with the injectors. It is not uncommon to have IP issues after new injectors due to the higher pop pressure of the new injectors and the worn out IP.

Hopefully the IP is ok. That would be a big hit.
For an even bigger hit, it's best to replace both the injector pump and injectors at the same time. They all wear at about the same rate.
 
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Brian VT

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At this point I'm just hoping to get the cold start smoking gone so I can drive it when I want.
(It's not my primary vehicle yet until I get it sorted out)
Now that the warm weather is here and house windows are open I can't be fogging my neighbors every time I want to use my truck.
 

Old Goat

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You'll have to disconnect the return lines from each injector when you replace it. When you re-use the return lines there is every possibility that there will be a leak. If the lines are old they will have hardened a bit, and be more difficult to reseal. OTOH, they are easy enough to replace if they do leak. It's just time and effort and frustration. If/when you do replace the return lines be sure to cut them to the proper length. There should be NO curve between injectors down either side. A curve in those short spaces puts undue lateral pressure on the injector nipples where the lines connect, making them harder to seal. They seal much better if the line goes on absolutely straight. The longer lines will have curve by definition.

Before you pull an injector you might want to vacuum around the area, and wipe it down, and vacuum again. I suggest you do the vacuuming when your wife isn't home. She may object to your using her vacuum of your greasy engine.


Yeah I know what you mean by the curve in the hose.
I replaced mine several years ago, and bought rubber hose from O`Reilly`s, and it does have a curve when you cut the short pieces, and it s stiffer. trick is to alternate the curves, and it will go on straight. it never caused any leaks. The cloth hose doesn`t seem to have the problem.

Another trick is to connect all 4 cap together, then drop the assembly on and click the caps down. Be sure to grease them up good.
When you put the "O" Rings on, use some grease and slide the first one on the top groove. Then slide the second one over the top one to the lower groove.

If for some reason several months down the road you mess around and move one of the caps and it starts to leak. Changing the "O" Ring on the leaker, you will move the next one and so on, and more leakers. Just pull the whole side off, and replace the whole row of rings.
Not a big deal, just a P I T A thing that happens.

You can buy the rings off Amazon or McMaster-Carr. 50 for around $10 a bag, size 111.

Goat
 
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Brian VT

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When you put the "O" Rings on, use some grease an slide the first one on the top groove. Then slide the second one over the top one to the lower groove.

Goat
Good idea. Then you're not damaging an o-ring by dragging it past a sharp groove.
 

Brian VT

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If/when you do replace the return lines be sure to cut them to the proper length. There should be NO curve between injectors down either side. A curve in those short spaces puts undue lateral pressure on the injector nipples where the lines connect, making them harder to seal. They seal much better if the line goes on absolutely straight.
Like I said, the ones on there look new. And I suspect that the shop that sold it installed them soon before I bought it. That said, I just took the air cleaner housing off for the 1st time and the lines do have curves / are slightly longer than they need to be. But they don't look to be leaking.
I may still elect to replace all the caps and hoses since I do have new ones here.
 

Brian VT

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I got an in-person look at what I'm up against.

I was hoping to not have to mess with the IP. I was hoping to just loosen the injector line supply.
I didn't realize that there was a hard line from the IP to each injector.
Should I stick with my plan of loosening/removing 8 hard lines so I can change my injectors or is messing with the IP the better plan of attack?
 

Nero

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I've always replaced injectors by loosening the isolators and just flexing the lines out of the way. Mind you, you shouldn't do it that way, but so far I have no leakers. Make sure the isolators get put back on, they're there to prevent the lines from vibrating and breaking off.
 

Brian VT

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Thanks. I may start with that and see how much wiggle room that gives me.
But I sure don't want to have to replace those hard lines because I kinked them or something like that.
 
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