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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
My car has been sitting for several years without running. I have a access panel cut for the sending unit so I pulled the sending unit out and the gas that was left in it was nasty. Did not smell like gas, so I pulled the tank and drained it out. I planned on replacing the tank anyways. I am also replacing the old steel fuel lines (supply, return and vapor lines) with new stainless steel. I don't want to pull the top of the engine apart to pull the fuel rails to flush them out. I cm up with a idea and thought I would post it here to get some feedback as to would this work (see attached picture). Basically, I am going to use a 4-7 psi electric fuel pump and circulate gas through the system to flush it out. Thoughts or better suggestions?
So how is what you’re doing any different than running the fuel pump normally? Normal operation would actually do a better job of flushing since the pressure is an order of magnitude above what you’re attempting to do. Have the return line dump into a bucket if you want to see if any debris is being removed.
The better way to clean the rails would be to remove them, disassemble, and physically clean with some strong solvents and a brush to get any varnish out. I understand you don’t want to do this, but that’s the right thing to do if you’re truly concerned about getting any nasty stuff out of the rails.
Removing the rails isn’t really that time consuming.
Removing the rails isn’t really that time consuming.
Honestly, it only takes a few hours at most to do it right. All you have to do is remove the plenum and one or both of the runners. Four bolts and the rails are off. I assume since you were cleaning out the whole fuel system that you were going to replace the fuel pressure regulator diaphragm, right? If that's the case, then you already have the plenum off. If you're going to spend all that time to build and run a custom set up, you could do it the right way without much additional work/time.
I agree with the others, put all your time into taking off the plenum and runners instead of building the custom setup, then you can just hose out the rail with carb cleaner. This would also be an ideal time to make sure your EGR canister is in working shape, install a new fpr diaphragm, and ohm the injectors to verify they are all in spec. Reassemble with new gaskets.
Plus, you'll have great access to clean everything underneath the plenum.
I went thru this exercise after the car had sat for 25 years. Took it a step further and pulled the intake as well. soak that bad boy in Totally Awesome (its cheap and very effective) for a few days and you'll be shocked at how easy it is to get the crud out. Then, grab some kerosene and clean out the valley, mine had sludge built up in it. it was tedious, but so worth it. my engine oil is so clean between changes, its like a brand new engine. at first I filtered the kerosene to reuse it, just kept draining it out the oil pan (of course drained the oil first). then after it was not getting much, started using fresh kerosene and finally, topped the process off with an oil change, ran the engine a bit to get any remaining kerosene out, and finally, a final fresh oil change, may have done this twice, forget, but would not put it past my self.. You might consider replacing your EGR valve and fuel pressure regulator while in there, you'll have easy access.
As others have said, no need to make up a custom pump/piping apparatus to flush the fuel rails. Once you have the tank cleaned, new fuel pump, new fuel lines and new fuel filter, just disconnect the fuel return hose from the rail and put the end into a bucket. Put fresh gas in the tank and turn on the fuel pump. It will flush the rail and pressure regulator and dump the dirty gas into the bucket. Reconnect the return line and then see if it starts. The injectors and/or fuel pressure regulator may or may not be all gummed up. See what it does, but more than likely it will need a new set of injectors and fuel pressure regulator. Also might as well tear down the fuel rail assembly and replace the o-rings. Southbay has everything you need.
Going to pull the fuel rail out to flush them out, check the EGR and pull the fuel pressure regulator and check it out (when the North-East Ohio weather allows me to). Going to check the injectors while I have everything apart. On a separate note if I do have a bad injector, I was thinking about replacing them all at once. Which brand is better then the other?
305 southbay has refurbished injectors that work well , there d3 require tuning or delphi for 350 or tune.
if there multec save your self a headache and replace. Probably all gummed up if sitting with non stabilized fuel.
Manual lists for a 87 305 TPI OEM are 19Lbs injectors. I was looking at South bay 19lbs injectors,new listing at 150 for a set of 8. Not sure of the brand currently in vehicle, never checked or pulled them. Sounds like good advise to replace them. Thanks!
Bosch injectors have different voltage offsets than the factory injectors, if you go with those you may also need a tune. The Delphi units are equivalent to the factory injectors, but they cost more.
01-17-2022, 09:09 AM
