When we check the fuel pressure with the main line disconnected from the engine into a gauge we get 63 pounds. When we put a tee fitting and have the engine running we get 35 pounds. When we rev we get 40 pounds. Is this ok? The book we have said we should have 72-90 pounds - now we're confused as to which reading we should have where?

 

Sounds close enough for government work. The manual that is free on line says it should read 64-85.3 from the pump (isolated) and 28.4 at idle with the tee , and if you rev the engine the pressure regulator should go to its other schedule and read 35.6-37.0. Your reading vary a bit from the above but I do not think you are lacking in pressue. One thing I have learned on this forum lately is that on the fuel pump itself there is a fine mesh strainer. Although the pressures read good doing the above test, when the engine has a load and needs good flow, this strainer will cut down on the flow. I discovered this when I had a problem going around left corners with a low fuel level. The strainer was impregnated with varnish and prevented a good flow. I took it out and let it sit in laquer thinner overnite and blew it out. Since then , with the fuel needle on the low mark, I can fly around left hand corners at will and the car will not cut out momentarily as it did prior to this process. Looking back at your post I guess the 63 lbs is a bit low but the other reading were ok. Wrecking yard charges about 40 bucks for one. By the way my figures came out of a factory manual for a 87 N/A. Oh yes, I blame the varnish on the injector cleaner put in the fuel tank. Where in the world did I think the crude loosened in the tank itself would go?