+Vasim Barmare thank you.

Doing the dye can pinpoint it, but sometimes when you start getting one leaking, more are likely to leak soon. Normally we just change them as they fail though.

I was doing the same by changing all the injector whenever there diesel mix, this video is going to help me and the customers. Thank you very much

+Mark Armstrong Thanks for subscribing and watching them.

Thanks so much Ken. Thanks for watching the channel.

Thank you, I'm actually working on one right now.

Nice, all the videos I have watched thus far, are really informative..thanks

+raj gill Its a good idea to have that checked and make sure the level doesn't keep getting higher and higher.

Thank you, I like hearing that people watch them and enjoy them.

+Adept Ape hey great video, just wondering what else could cause fuel in oil contamination?

+Anthony Koulizakis Well I mentioned a few of the other possible locations on a Cat engine. The high pressure fuel pump, fuel transfer pump, a severely damaged cylinder could leak it into the crankcase or a cracked cylinder head fuel rail, but usually it's the injectors or injector lines.

I'm glad you like them, not sure if they're amazing, but I think I am getting better at making them. So if your oil is diluted you'll start getting less oil pressure because the viscosity will start dropping, that is a good way to tell. Thanks for commenting.

I'm glad you like them, not sure if they're amazing, but I think I am getting better at making them. So if your oil is diluted you'll start getting less oil pressure because the viscosity will start dropping, that is a good way to tell. Thanks for commenting.

+Adept Ape you wont win an Oscar for them, but i meant the content is very helpful. There are a lot of guys with automotive youtube vlogs, but non that cover detailed diesel engines like yours. Hopefully you will be able to get into a diesel rebuild in the near future!

+Regal2800 I know you've between requesting a rebuild video for months, but I haven't had to do a rebuild in a few months, mostly engine swaps, but I'll try to film the next one I do. I think it would get good views too. Thanks for commenting Regal.

+raj gill Thank you, yeah I'm not real close to Calgary.

Did you have this problem? Who fixed it for you?

@@saqi88 it was a bad injector cup and luckily fining calgary was working on truck engines that time so got it fixed from fining.

Farm Tractor

... I found a DD procedure in DD Service Manual 6SE164 MAY 1994, Section 2.0 (Shop Notes - ... ), Pages 17, 18 & 19 ... three fuel leak test methods are outlined, the 1st being observation under the rocker cover of oil puddle presence / weakness / absence (at fuel pipe connectors to head / f.p. nuts to head conn.'s & injectors / f.p. & nut interfaces) following 20-30 min.'s of run time (DD stresses oil puddle inspection as 'key'). The 2nd (engine static) & 3rd (engine running 400-600 RPM [fuel pressure to be regulated higher to 70 PSI by an introduced return line valve]) involving pressurizing to 60-80 PSI with fuel (not air, as per my earlier recollection) ... these latter two methods involve tools I don't own ... which makes my one-off t/s initiative somewhat problematic and less than cost-effective in the scheme of things ... an air pressurization procedure may exist but I don't know where it might be found and / or if it would even be appropriate, should I choose to ad-lib ... I'm liking A,A.'s dye test method more than ever *except* that it requires a running engine (mine has no lube oil in it, at all, as I anticipated further fuel loss / leakage into the crankcase during testing) ... I'm still trying to track down a local (to Vancouver, B.C., Canada) Spectroline supplier (for dye & appropriate UV flashlight tool) ... CAT wants $17.22CAD (+5% +7%) for the 1 oz. bottles of dye ... nearest inventory to me is Spokane, WA ...

The injector is the usual cause. Good luck with your new career.

+Jay Hoeft Yeah those older mechanical engines like the 3406 and 3300 series could leak through the injection pump. I've also seen the fuel lines leak under the valve cover going to the injectors.

the fun ones are the fuel jumper tubes Detroit 2 strokes

R5

+LET'S MAKE A BETTER WORLD Thank you, not sure about the legend part, but I'm glad you like the videos.

my cummings 5.9 isdoing this ??? is the lift pump/ injection pump / or injectors at fault? just put on rebuilt inj. pump

+adam7e I have never seen one caused by a 3126 transfer pump, it is possible though. The transfer pump is driven by the back of the HEUI with a little armature. I guess if the seals failed and then sent fuel past the little armature seal, it could leak into the HEUI pump, but my guess is it's one of the injectors.

Thanks man! In the video you mention that the troublesome injector needs to be removed, and replaced. This must mean that this kind of leak is internal, and not caused by failure of the o-rings/seals on the body of the injector?

+adam7e Typically the injector orings seal the fuel rails in the head. If you do this test with the black light and there is any fuel on the injector, meaning it's coming out of the body of the injector, the injector should be replaced. If the leak is just around the base if the injector where the external oring seals the head, then that can be replaced, but on a HEUI engine, 3126 and C7, those external seals keep the HEUI oil sealed as well, so you see an engine oil leak at the oring and not a fuel leak.

If I had an oil leak at the oring in addition to an internal leak within the injector body, might that put oil into my fuel tank? If so, what's the best way to go about inspecting the fuel?

+adam7e An oring seals the fuel rail and the oil rail in the head from each other, so if the oring between rails, which is your center oring on your injectors failed, it would pump oil into your fuel system. The injectors themselves can leak internally and do this as well. If your fuel starts turning black from the oil, then you know you are cross contaminating. If your looking to fix it, you can reseal the injector orings, which isn't too expensive if you do it yourself. Hopefully it's just an oring, if that doesn't fix it you pretty much have to change the injectors as a set. Now you can try calling a Diesel fuel shop and see if they can test HEUI injectors for internal leaks, but as a dealership we don't have a way to test them so we replace them. Hope that helps.

Injector O rings.

I would suggest a rebuild if you really need it. An engine swap typically would cost you more. Definitely go with the 6NZ if given the ability to get either.

+Omar Well there are seals external and internal on the injectors, if you see oil coming out around where the injector inserts into the head then it might just be an oring, if it is the solenoid or body of the injector, then the injector has to be replaced. Just normal wear can cause this and it is a somewhat common problem.

+james gonzo That is the second request for that this week. I'll try to make that next week's video since it seems there is a lot of interest in that. When my channel was new I made a 25 minutes video about it, but nobody watched it (I had a 5 subscribers then) so I took it down. It wasn't that great if of a video then anyways, but I'll make a better one.

Did you find the cause of the problem?

@@bmwe657er its was unburnt diesel from cars regen cycle not being complete. I changed oil it was fine. Just made sure I did at least 1 long journey a month for dpf to regen

Did you get it fixed? If so what was the issue? I'm having same issue with my C15 fuel in oil I'll do the dye test, and also just sent in oil sample for confirmation.

@@TolaTrucking yes I got it fixed it was my plungers in my pump. On that c15 one of your injectors got to be leaking. If you take off the valve covers look on the top of each injector they should have oil on top of them. Look for one that doesn't have oil on it and it's clean. That's going to be your problem.

I'm going to be checking my messages so I will come back later to see if you was able to get it. It's not hard it sometimes get to you when you don't know I'm here for you bro.

At dealer

If it was mechanical you'd still be looking at the injectors with the same diagnostic process the only thing different would be where its leaking at the injector. (Feed or return leak possibly caused by a combustion leak.)

Working on a 3406e same problem fuel in oil. Runs great, no smoke, or starting issues. issues . Did the same test no luck transfer pump next?

+zeer365 Sounds like a cracked head or head gasket most likely. The air compressor can also fail and put coolant into the engine. Typically if you have coolant coming out of the exhaust it is had related. Check your precooler and then do a bottle test as well. I have a video how to do a bottle test, it is very easy to do.

If timing case or cover gasket damaged also getting oil in coolant

I have the same type of fuel pump but it’s a N844 4 cylinder. Did you find the problem?