Lubro Moly Diesel Purge
- Thread starter Greg_B
- Start date
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ostacruiser said:
Sorry, I can see how I wasn't clear:
I used to get 26MPG highway. In the last year it has been down to 24. On the last tank of city/highway I got 26.5 so I'm hoping all highway will be even better..
So anyone have any places to buy this on the internet without paying high shipping charges? Seems like a limited amount of places sell it.
How do you guys pour it in your fuel filter in a 3B? Do you just unscrew the top two bolts and pour it in?
I don't think that is the best thing to do on a 3B.
The purge loosens a lot of junk, so I worry that when the return from the injectors goes back into the injection pump it will bring with it lots of junk(carbon) and then it will get re-stuck, or go for the ride again thru it all(endless cycle)...as the filter is pre injection pump.
IMOP on the 3B you need to somehow trap the return fuel from the injectors,
On my Mercedes I used a jug with two hoses, the jug was full of crap at the end. I used an inline filter out of the jug too.
If your engine runs fine(no smoke) then don't bother. If your engine smokes and you have not had the injectors done, then do the injectors.
If you want to figure out a way to re-capture the fuel from the return and set up a jug system, I will help with ideas.
If I had not done my Mercedes with the jug I would not have known how much junk will come loose.
I think with out getting rid of this loose material it will cause more damage than good.
In a return to tank system vehicle the junk just goes to the tank, then gets captured by the filter before use... no biggie. But on the 3B I would be very very careful.
When people talk about smoking, are they referring when it is heated up and driving or during start up?
My truck puffs a bit of gray/white smoke when it's cold but it goes away after it's warm. I think it might just be condensation though.
the injector tips is where the carbon is, and the fuel is going to push most of the carbon out, undo the line for the injection pump, dunk the line into the tank right to the bottom and run at varying RPM till it shuts off, reprime.. drive. i say this because even the most foul diesels we treated at the shop with this stuff never puked out any wierd stuff from the return line. thats the way i was taught to use this stuff from any of the old VW/ mercedes mechanics that i saw use it. the only sucky part is.. having to prime some of those old diesels! out of the injectors ive had apart... it seems highly unlikely that any carbon on the tips could flow upstream and get into the return line, that said lubro moly might remove accumulated buildups of diesel constituents and force them up the return, but these components most likely arent abrasive, realistically.. Fuel impinging on metal at a few thousand PSI is abrasive anyways. The real issue is that High EGT's ruin fuel injectors in a viscous circle long before carbon does any real damage.... and Over EGT does cumulative damage, so only a minute here or there does the real damage the same as a straight hour of it would...
try this.. when you start your truck, no matter how cold it is, resist the urge to press the accelerator or the PTO idle up, if you have to give the truck some fuel to get it to fire, so be it.. but IMMEDIATELY let off and let the truck idle at its factory set low warm idle. note: it will be slower rpm cold, than the set warm idle. let the engine speed up on its own without using any fuel at all.. and watch that smoke dissappear. the other thing that can cause smoke on startup is that the injectors leak down after shut off and leave fuel deposits sitting to cause smoke on the next startup cycle, but then only usually for a second or so, assuming the valve seals are still good and its not engine oil. try not to touch the accelerator and let the truck idle on its own for ten fifteen seconds before using the throttle lock or touching the accelerator!
I ususally shut off the truck when it's around 750ish RPM, when I start it up though, it tends to be quite low, below the lowest line in the tach, so under 600 and the truck shakes violently.
I'll give it a try to see how long it takes to go back up. Would it damage the engine if it idled that low?
when its cold, no it wont hurt it.. especially not a 3B. the crank and main journals are engineered to operate with oil pressure as low as 4.3 psi! yes FOUR POINT THREE PSI. they have ample surface area and good tolerances to deal with this, and thats why they last forever, because even the most worn out diesel will operate under these conditions. in reality, your engine will be running much higher pressure than this in fractions of a second, so there is no need to worry, sure it shakes.. but its only for a few seconds, untill the chambers can support complete combustion and you give it some fuel, ten to fifteen seconds, max.. depending on ambient temperature my 3b is ready for fuel higher than idle within three seconds of shaky idle. i should add that , this winter i also experimented with bringing the idle up to the lowest line on the tach with the throttle lock straight after start up with minimal amounts of smoke.. overall i dont think you will ever hurt the crank, if the engine shook for a prolonged period there might be risk of motor mount fatigue.. but then again i know mine are tired and thats what allows it to shake in the first place, 3b factory idle set is 650, straight from the manual..
cheers
cheers
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lots of s*** came out of my pump/lines and nozzles when I did my purge. Enough that I would not want it going back in for a endless cycle.
But each to their own.
I see no point in letting the engine shake heavy on start up. Bump the throttle up to 1,000 rpms and let it warm up..
What was the reason to let it shake at low rpm again???
But each to their own.
I see no point in letting the engine shake heavy on start up. Bump the throttle up to 1,000 rpms and let it warm up..
What was the reason to let it shake at low rpm again???
revving a cold 3b to 1000 rpm at startup is not so that it can "shake", hahaha. its to keep piston velocities low in a cold bore, and allow combustion to warm up the burner cups to a point where combustion is even. adding more fuel cools the chamber down and create incomplete combustion and white smoke, an operating area where you are also washing the cylinder walls with diesel increasing ring wear on a loose piston / bore tolerance, revving it at one third the rev range (@1000) rpm is too much fuel in a cold engine, the shake at 650 rpm is because every 3B out there sits on mounts that have been in the truck since new and the mounts are getting old as are these engines. let it idle.. just a couple seconds, the rewards are manifold, did i mention oil pump cavitation in cold oil and the resulting engine oil starvation?
to illustrate my point, on a cold day, lets say -20c, you go out and start your truck.. it starts and you rev it to 1000 rpm with the throttle lock and "warm er up".. you go inside and grab your coffee, the paper.. whatever, when you come out after between a minute or five, where does that tachometer needle now point and why? if you can answer these questions, then you will see that the fuel for initial startup and to reva 3b to 1000rpm COLD, is a lot more than what is needed to rev an engine that has been running for one to five minutes up to 1000rpm.