4010 D injector line leaks

[griz50]

Thanks to the many posts here from you JD gurus and the JD Roosa Master manual I was able to disassemble, clean, and install a seal kit for my 4010 DB injector pump. I finally got it all back together today and after a little starter cranking it fired and seems to run quite well also starts fast. However, I soon noticed small fuel leaks on several injector lines, and I replaced all steel washers with new ones. Some leaks are at the pump and others at the injector. I"ve tightened them all I think I should before I risk twisting a bolt off. Does anyone have a suggestion or a fix for this? Thanks

 

[Allan in NE]

Yeah,

They always seem to do that when they heat up.

I just watch 'em for the first day and snug 'em up as necessary after the engine gets good and hot.

Allan

 

[msb]

What I have always done to eliminate those pesky leaks is to wash all connecting parts in Deere paint thinner . Then blow dry. There is more than enough microscopic dust floating in the air to stick to any trace of diesel fuel on the fittings which will cause those leaks. If you don't believe this, try dipping a clean piece of glass in fuel and watch the dust stick to the glass surface even in a shop that you think is clean.It doesn't take much since the injection pump will exert as much as 5,000 PSI on those lines and fittings, even though the cracking pressure is much lower.
Then if you carefully observe the T20055T washers, they are stamped out of scrap sheet metal and are convex in shape. Place the cupped surface towards the banjo fitting on the lines so they look like this; (I). Next, do not distort the lines in any way when you tighten the hollow bolts. If you do, vibration will soon loosen the bolts and cause then to leak as those lines will "go home" on you. Finally , replace all line clamps in exactly the same position as they were removed from. If you follow this proceedure, you should rarely have a leak.

 

[griz50]

Thanks msb & Allan for your responses. I haven't yet worked on the 4010 yet, been busy this weekend. I would ask msb now, if by loosening the injector clamps, and the return line hollow bolts first, enough to allow for free movement, then loosen the banjo fittings far enough to drain fuel, will that comply with your suggestion of cleaning washers and fittings with JD paint thinner? Also loosening those items may work to ensure what you said about not distorting the banjo fittings for tightening. And yes I believe you about fuel immediately attracting and sticking to surfaces. Amazing how much crap floats in the air. I welcome anyone else to respond. I'll share whatever I can from this also. Thanks, Dave

 

[griz50]

I finally solved the leak problem. The tip from msb about cleaning those banjo fittings in paint thinner then blowing them dry helped a lot also tightening them a little more. What else I"d like to share is, the low pressure banjo fittings on the return line on top of the injectors was also causing much of the problem. I didn"t notice it right away until I looked closer and seen fuel was seeping outand down to the high pressure banjo fittings thus making it appear they were leaking. I took the return line completely off to inspect why many of the fittings leaked, I"m still not sure except that they looked scarred a little but they never leaked before and all I did was clean them. When I reasembled the return line I put a light coating of copper coat liquid on each washer on both sides and that stopped those leaks.

 

[tim s]

I have had trouble with those before also, I have filed them with a fine file,changed banjo bolts and all, they can be nasty to dry up, I'm glad Deere got away from those..

 

[griz50]

Yes Tim, after going through this some local mechanics have said they are a problem, can be tricky ect. But I guess after cleaning them retightening and whatever else they tend to stop leaking. I even loosened some bolts on the high pressure fittings after leaks were stopped to purge air and when I retightened they never leaked. Not an exact science. Dave