Dirty Fuel Injectors?


(JLo) #21

My 30 year old injector screens


(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #22

Were they a problem? Did you install new ones?


(JLo) #23

Surprisingly no issues maybe a slight unjulating idle but replaced w new. Got from @John_John1


(Philip Lochner) #24

They may not leak immediately, but they WILL leak… sooner or later.

The surest way to avoid leaking fuel rails (and potentially engine fires) is using the correct size : 7.6mm.


(Greg) #25

I went ahead and paid SD Faircloth to cut hoses for me with the injectors he cleaned, I assume he uses the 7.6mm instead of 7.9mm (5/16")?


(Philip Lochner) #26

I dunno, sure hope so. You should find at least one pipe that shows its dimensions.


(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #27

Don’t worry about that, it’s nonsense. The injectors were made by Bosch, and Bosch doesn’t design their injectors to use oddball size hose. The correct size hose is 5/16" or 8mm. It does have to be the correct type hose, though, hose that’s designed for push-on fittings.


(John B ) #28

I just pulled my rail and injectors on my 1989 XJS - did the soldering iron method - still “work” but did the trick. I am sending them off to SD for testing and cleaning. However, I have ordered hose, ferrules, and seals from XKs and plan to install myself. I also ordered new fuel line and will replace all but the ones under the car. I also plan on making up a new harness with SXL cross-link wire, new connectors, and high temp sleeving. The harness will then go along the rail and not back in the V. Good to know that the rail is steel - I will paint mine. What about the injector mount plates? Are they steel too?

I have some questions on the hose install - what are the spec lengths for the hoses? I have seen 1-3/4" for 2s to 6s; and 3-3/4" for the #1s - is this right? Also any insight on cutting the hose and pressing back onto the injectors and rail? How about testing once the job is complete? I like the colors JamesL has - but looking at his 1s - are the connectors facing the wrong way (back)? My 1s face forward.


(scrimbo) #29

Cut carefully with exacto. …laterally. Remove rail then operate on cutting.


(JLo) #30

Or you can let your lady do it


(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #31

How do you expect SD to test your injectors without hoses? They’ll probably install hoses, meaning you’ll be left to choose whether they come off again or just stay put.

Yes the injector mount plates are steel. You could check that with a magnet easier than typing the question.

The rear five hoses need to be exactly 1.75". Either longer or shorter causes problems. The front one on each bank is a bit more flexible; I just installed the hose on the injector, bent it over toward the rail, and cut it off where it looked right. No biggie.

Easiest to assemble with the injectors on the engine. Don’t use any lube on hose or barbs. Press the rail down onto one bank of five until it’s fully down, then pull back up on it. It should grip like a Chinese finger trap. Once secure, line up the other five and repeat. Unless your barbs are messed up, it won’t leak.

The injector connectors can be turned to face either forward or rearward, but you can only make that change while the hoses are off because you have to flip the injector mount plates over. I lined mine up so they all face the same direction because to me they look better that way.


(JLo) #32

Hi Kirby,
Just curious why you advise not to use any lubricants while assembling hoses?


(Kirbert - author of the Book, former owner of an '83 XJ-S H.E.) #33

These are push-on hoses. They don’t need lubrication, and lubrication may cause them not to grip the barbs properly.


(Greg) #34

It’s easy enough to put hoses on one at a time with rail off car. Just push hard and twist, they will NOT come off.

I also added even more hose coils to my car :slight_smile:


(Aristides Balanos) #35

Cool idea and looks very nice.


(John B ) #36

Thanks for the info Kirby! And - I like what Greg has done with his rail and injectors - just got done cleaning and painting my rail and bits - same silver as Greg. I may add the hose coils (looks great).

I haven’t put things back together yet - took a few more steps - removed the intakes, air rails, fuel lines, cam covers, as well as the exhaust shields - the more I dig, the more I check and remove. Bought the after market half moons, banjo bolts, AAV piston, and thermal bulb - along with new heater hose, vacuum hose, gaskets, o-rings (etc). I am chasing and few leaks in the lower right front - not sure if it is coolant or oil yet - one step at a time.

I have been taking photos - and will share soon , when I get to the assembly part.