RENIX fuel delivery questions

[Zoro]

Working on an AMC Eagle with a transplanted 4.0 from a 1990 Cherokee. It has been parked 10 or 15 years and I am trying to get it running smoothly again. I have it running and driving but it idles rough, stalls when you stop and shudders from time to time under acceleration.

Fuel pressure at idle when idling rough is bouncing from 18-30 and 30-40 when driving. No drop in fuel pressure prior to the stall. Brand new FPR and no vacuum leaks.

Vacuum pressure is about 8-10 at idle and very steady.

Current fuel pump is external, eventually going to an in-tank.

What pressure does the fuel system like between the pump and FPR? Can anyone recommend a good external pump for the RENIX?

Thanks!

 

[Anak]

I don't have any answers for your question, but I would love to know more about the conversion and how everything fits and works together. I have toyed with this idea myself. I know where I could probably pick up an Eagle, and I have wondered about converting it to a 4.0L from an XJ.

I would be interested in anything you can share about the swap. Pics would be appreciated, but I understand the problem with the hosting.

PM me if emailing pics would be an option.

 

[Zoro]

Sure thing. I have owned a few eagles and I’ve had my eye on this particular one for years. Some friends of mine bought it from the guy who did the swap. Pretty sure the guy that did. The swap is on here somewhere. Aside from a little bit of wiring clues. The whole swap looks pretty stock.

Drivetrain is a 1990 4.0, TF998(Stock eagle trans) and transfer case is the NP229 from a grand Wagoneer. Stock case is the 129 so essentially this transfer case is identical to stock, except for the low range.

 

[Anak]

Thank you.

Definitely food for thought.

 

[Ecomike]

Working on an AMC Eagle with a transplanted 4.0 from a 1990 Cherokee. It has been parked 10 or 15 years and I am trying to get it running smoothly again. I have it running and driving but it idles rough, stalls when you stop and shudders from time to time under acceleration.

Fuel pressure at idle when idling rough is bouncing from 18-30 and 30-40 when driving. No drop in fuel pressure prior to the stall. Brand new FPR and no vacuum leaks.

Vacuum pressure is about 8-10 at idle and very steady.

Current fuel pump is external, eventually going to an in-tank.

What pressure does the fuel system like between the pump and FPR? Can anyone recommend a good external pump for the RENIX?

Thanks!

If it is Renix 4.0 transplant then the FPR is vacuum regulated, with a return line to the fuel tank. If the FPR diaphragm has a leak, you will smell fuel in the vacuum line attached to it (engine off), if you remove the vac hose, you may feel gasoline at the vac hose nipple on the FPR. After 10-15 years sitting it may be leaking. Also just disconnect the vac line, do not crankor start it, turn the Ign switch to run, test the fuel pressure. If is not steady, it is leaking. It should hold pressure with the engine off.