MFI too lean on 2 cyls

[kentf14]

Question for the MFI gurus.
I'm running pretty lean on cyls 3 & 6 while all the others are on the rich side.
Can anyone advise the best way to get 3 & 6 a little more enriched?

Please excuse my ignorance!

[Chuck Miller]

Can anyone advise the best way to get 3 & 6 a little more enriched?

Unless your injectors are brand new (and still have been checked on a spray bench) I would say you probably have a couple of bad injectors...

[kentf14]

That was my suspicion too Chuck. Maybe I'll pull them and go swing past Gus to see if he can help me out.

[kentf14]

Chuck (or anyone else). Do you know if the copper injector sealing ring can be reused, or is this akin to typical crush washer in that it's one use only?

[kenikh]

Start by having your injectors tested. A knowledgable MFI guru will test for spray pattern, opening pressure and volume/time to see if they are in spec. If in spec (and the fuel lines are confirmed clear) you'll be looking at a pump repair/rebuild. If the injectors are gummed up, they can often be ultrasonically cleaned and retested. If they still fail, you're looking at replacement.

I'd recommend Mark Jung over Gus, only because Mark's turnaround is super fast. He can handle the injectors, lines and pump. He did my 69S pump and I'm glad I did.

Edit: since you're close to Gus and can do drive bys, you can't go wrong there!

[edmayo]

Yes, the copper sealing ring can be reused.

[kentf14]

Thanks Ed! Do you know what the torque spec is for the injector into the head? I can't seem to find it in my workshop manuals.

[edmayo]

Of course not,,,,I never torque that kind of stuff when you're in the profession you'd better have a feel for most fasteners! I can tell you that normally I use a combination 17 wrench and I don't pull it as tight as I could possibly,,,,, but close!

[jrbennett]

I too just tighten by feel, but...

the Technical Specifications book list a torque of 3.0 mkp. So approx. 22 ft/lbs

[kentf14]

Fair enough guys. I'm never sure if my arm is in calibration.
Now I just have to wait for the 17mm flare wrench to come in the mail.