drscottsmith

Does anyone have/know of a good writeup for a 4.7 Intake refresh? Just want to start wrapping my head around the process as I know it is going to be coming up in relatively short order.

Saerching RL and Google brings up a number of 5L engine procedures but I can't find anything for the earlier engines.

Thanks -

-scott

Daniel5691

As the local idiot, I offer the following with all appropriate warnings (i.e., I do not know what I am talking about...)

1983 USA 928S should be the
Manual Transmission M28.19 Bosch LH-Jetronic fuel-injection
or automatic transmission M28.20 also with the LH-Jetronic....

Here's a link to the Bosch LJet "intro manual"...http://www.cardiagnostics.be/-now/Ed...n%20Manual.pdf

and here's a really cool thread which details some testing procedures for the LHJet... https://rennlist.com/forums/928-foru...nt-thread.html

Here's a 188-page monster procedure for the earlier-year's timing belt/ water pump job. I use this as a good general guide for my 1981 928S. The explanations are very helpful and DETAILED....http://jenniskens.livedsl.nl/Technic...ber%202011.pdf

How far "down in there" do you plan on going? All soft lines/hoses/ fittings?
Powder-coating the pretty stuff? Is the car currently running nicely? Do you notice any obvious leaks at this point?

I would definitely include the soft fuel lines in a refresh if those are not new. That can save you from a kaboom.

Pictures?

Good luck !

drscottsmith

Daniel -

Thanks for the reply. My car is currently not running (purchased that way). I hope to have that solved this weekend.

Step one after getting it running is getting the engine and underside cleaned up. There is evidence of a lot of leakage, but I have no idea how old. Once it's cleaned I hope to be able to pinpoint the issues.

Since there is obvious neglect, I am just assuming that not much has been done maintenance wise over the years...I am just assuming that vacuum lines need to be replaced (as well as all fuel lines). Not sure what kind of shape the AFM will be in at this point. When I dropped the gas tank to clean and replace parts, the old gas (varnish) smell was pretty strong, so I am sure a good injector rebuild will be in order.

So, that is a guess at this point. I might get it started and it run better than new (nah...what am I thinking) - I just wanted to start reading to wrap my head around the job beforehand.

I think my biggest concern is the best way to get the spider and AFM out without messing it up, as well as any tricks to fuel delivery items.

Thanks -

-scott

Majestic Moose

There is not much to a 16v intake refresh. Remove the airfilter and one bolt on each side of the lower airbox and then lift it out with the AFM still attached and unplug the wire harness.
Disconnect each end of the fuel rails while counterholding, cut the zip ties attaching the injector wire harness to the rails and unplug the injector connectors, then remove one bolt from the injector hold down plates and now the rails and injectors are free.




Loosen the hose clamps from the intake legs and remove two 13mm bolts from each leg for removal. At this point the 'spider' body is held on to the throttle body with a large hose clamp on the underside. Once removed you have access to all vacuum and fuel lines. Check the rubber three-way vacuum splitters, mine looked ok but when I checked them they had cracks in the 'crotch'.

drscottsmith

Thanks Alex - perfect!

-scott

Chris Lockhart

Good luck Scott!!

drscottsmith

Oh still a ways to go....parts are supposed to be here today from Roger...with a lot of luck and crossed fingers we may have ignition this weekend.

How's the engine coming along?

-scott

Chris Lockhart

I ran into some unexpected issues , and had to pull the studs and start over. (Apparently I didn't clean the threads in the block as well as I thought I did and the Loctite didn't hold. Studs turned when I went to torque the head.) I "should" have it all going properly this time around. I might be able to get one head done on Sunday. We'll see. Gotta work tomorrow, then a birthday party, then babysit my youngest granddaughter so I'll be busy as heck. LOL.

drscottsmith

Good deal - glad it is coming along!! I am going to get by there one day soon.

scott

Chris Lockhart

Scott, next weekend should be a 3 day'er for me, so if you need an extra pair of hands shoot me a text. I'd like to see your new baby. Have you been able to get it to fire, at least for a second to know the engine isn't trashed?

drscottsmith

if the mail will run (gotta love the us postal service in Duncan, SC), my parts from Roger should be here today. Once I get those put in, we'all be ready to try to start it up.

i do know it turns over. Oil in sump looks ok, so I am hoping it will fire.

cross fingers!