I found the throttle chamber to air regulator hose had a 1" long crack in it. It was very sneaky. I noticed it when I remove the hose to clean a sensor located under it.

Where is a good place to get a replacement hose for this? And that leads to another question, in general where can I get all the hoses I need to replace fuel lines, vaccum hoses etc...basically all the rubbers under the hood that might need replacement.

Thanks!

Yeah, that would definitely be a lean-running issue!

You can get the small dia vacuum line and smaller diameters of fuel line from your local auto parts store. Larger fuel-rated lines can be found at your nearest tractor supply, or you can call Hampton Rubber in Hampton, VA. If you ask them very nicely, they might mail-order you what you need. (They have EVERYTHING rubber in the known universe.) You'll want fuel-rated hose for the hoses to the air regulator and from the valve cover vent. Don't use heater hose.

And I thought I had found any/all cracked hoses :-) I am glad I found this one. Sneaky little devil. I have been inspecting them all as good as I can.

Thanks for the tip once again. We have a farm and fleet here, and I am sure they will have those kind of hoses.

PS

Do you think a lean running engine, can foul up plugs the way I mentioned them in my very long engine running description that I posted here....http://www.classiczcars.com/forums/showthread.php?t=40957

In my mind, it seems like fouled up, black, goopy plugs would be because of too much fuel not to little????

Well, EXTREME lean running can foul plugs from engine misfiring. I can attest to that from personal experience. However, the goop component might be something else. I think you might be burning oil in those cylinders. But you never know until you work through all the problems systematically. Even if you end up rebuilding your engine, you'll still need your fuel/intake working correctly, so nothing you're doing is wasted.

I have been inspecting them all as good as I can.

With the car running at idle, spray Starting Fluid around the engine vacuum hoses. If the idle increases where you spray you have a leak there.

You can still get a lot of these hoses from your local Nissan dealer...(if you have one local in your area) Just go in with a P/N and they are usually more than happy to order stuff in for you...Also see various hoses on eBay from time to time...

Can also do a search on "Spreadsheets" on this site...which you can use to help track stuff...these were all done for a 1975 280Z...so most items will be almost exactly the same...

webdawg1

Well, EXTREME lean running can foul plugs from engine misfiring. I can attest to that from personal experience. However, the goop component might be something else. I think you might be burning oil in those cylinders. But you never know until you work through all the problems systematically. Even if you end up rebuilding your engine, you'll still need your fuel/intake working correctly, so nothing you're doing is wasted.

I cant wait until spring time again. I will have finished some things to the car by then, and ready to run tests and drive the car. "Reading the spark plugs" is going to be a big hit for me. I will run at full load for a little while on the highway, pull over where its safe...and pull them out and read them.

I also think maybe the piston rings are worn enough (182,000 miles on her now)....to be leaking oil into cylinders. At least some of them. We shall see....:-)))

Oh well lots to do lots to do until spring time.