So we still have the Hummer. Today I'm going to try quite a few different things to see if
we can get it started again. I had originally discovered that the glow plugs were all fried,
so I replaced all the glow plugs, and then fried that second set because my glow plug controller
wasn't...it was staying at 24 volts forever and just frying all the glow plugs at the same time.
So I replaced the glow plug controller and now the glow plugs should be working correctly,
but it still just turns over and over and over and over. And supposedly you're only supposed to let
it turn over for about 20 or 30 seconds before you let it pause, and mine will turn over for like,
you know, 5 minutes if you'd let it. So today I'm going to check the fuel system
as well as the air filter and make sure that the fuel and air are getting into the motor
because I think that would be the next step in this equation.
So kind of a video about a lot of different things. Let's get started.
[Intro]
So this is the air filter. It comes in through this snorkel right here, comes into this. This
is my first time opening this up so definitely don't think I'm an expert in any of these things,
but it's still kind of fun to see how things work, so here we are.
So this particular Hummer has just been sitting in my backyard for the last couple months.
I did drive it about 150 miles when I first bought it, but other than that
it's just been sitting and now it doesn't start anymore. Who knows what's going on.
Yeah, still looks pretty brand new. There's a tiny
bit of dust in there but the filter itself....Alright, one check down.
I think it's going to be the ejectors that are the problem because when I did buy it,
they would always take a while to start, and I feel like those injectors are just super dirty.
But we're going to check the fuel filter first and then move on with the ejectors after that.
So the next thing we're going to check is this guy right here. This is called the fuel breather,
and this little vent is what lets air escape from the gas vent while you're filling it up. So this
is where the diesel goes in. Usually if you take this off and there's a pop, it means that the air
inside has created a vacuum. I don't think that's what's going on in my Hummer. And by Hummer,
I mean Humvee. But I'm just going to take this off because if this ever stops working and creates
a vacuum inside of the tank, then the fuel pump makes it harder for the fuel pump to pump the fuel
into the ejectors. Now once again, I don't know what I'm talking about. This is just what I've
read. Since this is just a vent I can leave this up here for a second while we try to turn it over.
Wait light going on. [Engine sounds]
Nothing. Didn't think it was that anyway. So the fuel filter is this guy right here,
and I'm trying to avoid, I mean I have the replacement parts but I'm trying to avoid
taking that out if at all possible. And there's also the fuel pump which might be an issue. But
there is a bleeder valve right here where if you just lift this
up, it releases some of the pressure and the diesel can come out of this hose right here.
But nothing will come out if the engine is not turning over. So what I'm going to do
is I'm going to hold this up with one hand while cranking the motor with this hand,
and we should see some diesel coming out this hose right here...if the fuel pump is working.
[Engine sputtering] And slipped, but you can see that fuel is definitely still
coming out after it's pressurized So that's good. [Engine sputtering]
So because the fuel system is pressurized, remember this is just me talking, I'm not
an expert in this, it makes me think that the fuel filter is probably fine.
The fuel pump is probably fine. It's probably the fuel injectors
that are the last obstacle to fixing this problem. So hopefully I'm right and we'll see what happens.
So before I got around to testing the injectors, my buddy, Brian,
came over and kind of hijacked my project and said we should test compression
first. And it turns out that it's really hard to test compression in these Humvee engines because
the government doesn't really get to that point. If something's wrong they just swap
the whole engine instead of trying to fix it. But we got this sweet little tool here on Ebay.
-See all the adaptations and all the angles.
-It cost us about $60, I'll give you a close up look right here.
-Because this is such high grade in order to hold the compression,
it's got to be really long, and so this has to be going straight up. So you have to have
all these angles to be able to get this teeny tiny little coupler to fit onto the tester.
-Because there's not a lot of room on either side of the engine to get into
the glow plug holes to test the compression. So we've already tested one and it was good,
so now we're going to test all of the rest of the cylinders just to make sure that the engine
is good before we move onto the fuel pump, and or the electronic glow plug gizmo.
-This is what we screw into the engine to capture the pressure. It's got a presta valve inside to
hold it. So that if it doesn't seal at 350 or 500 psi here, it'll still hold long enough to
register. But this is what couples into that. So you have this much length, plus this much length,
so you need to be able to make a 90 and get it in there so that you can get a good reading.
-You can see that the threads on this adapter and an actual glow plug are about the same.
And it goes exactly in the same hole to test the compression.
-So it's got a schrader valve inside of it to hold the pressure.
-Alright, so Brian's going to hold that. What we want to see is it move up to about the 300 mark.
And so I'm going to take the engine switch, go to run, and then...[engine
sounds]...perfect. We're right close to 400.
-Yeah.
-And so before I do that though, we've disconnected all the glow plugs and
make sure that none of the electricity is going and heating up the glow plugs while
we're doing this. Two cylinders tested – 2 cylinders good. Moving onto the next one.
-That's awesome. That's encouraging.
-So the reason we're testing compression is because in a diesel
motor, which I learned very recently, they don't have spark plugs, they have glow plugs.
-What I would say is that hot air ignites the fuel. Glow plugs just help get a little hot
air on scene for startup. And then from there the engine is warm on it's own and
the compression causes that hot air. So the compression is good. It's a little
low across all the cylinders. I think it was like 320ish on the lowest one. But all within
workable range Brian says and he's the expert. So the next thing we're going to replace
is the fuel pump, which is this guy right here. I'll put a link for all this stuff down in the
video description. But it's actually pretty simple to swap out. I'll show you where it's at.
So here inside of the engine bay right down here behind these is this guy right
there behind these cables that won't move. We're going to do it from the underside.
Basically we're going to detach this fuel line right here
and the two bolts that hold it to the engine block which are those guys right there.
So that line is the hard line that goes up to the fuel filter, and then the other line is the
rubber line coming from the fuel tank which is back there. This video is not sponsored by A&W,
although it is delicious. Very delicious.
-Finger trap! Usually run off a camshaft lobe.
Crank turns twice for every once the camshaft does so it's just slow enough to where it can just
give it a little tickle and the diaphragm that's pinched between these two parts
moves up and down and there's a check valve involved where it pulls it in, pushes it the other
way, pulls it in, pushes it the other way. It's like a syringe in fast motion. Fully automatic.
-So now we will get those two frame bolts put in, as well as the three hoses
and it should match up. We're just cleaning off the old gasket right now. [Engine sounds]
-You don't want to go more than 20 seconds at a time.
-Alright, it is now dark. We spent a lot more time on this project than we initially wanted to. But
the fuel pump was installed, but we still weren't getting any fuel because of this. It turns out
that there was a blockage between our gas tank, sorry, our diesel fuel canister fuel tank and
the fuel pump. So we're going to take this apart and see what that blockage actually looks like.
-So this is a check valve and it basically has a ball in it and there's extra room on one end so
that things can go this way and push the ball out of the way and get around it in that extra room.
It's designed to cause the fuel to only go one way so that it doesn't drain all back into the
tank. That way when you go to start it, you don't have to wait for the fuel to make the trip all
the way because it holds it at this point. This should be closer to the fuel pump in my opinion.
But you can test it pretty easily. Make sure it's clean. There's an arrow right there and it points
this way. So I should be able to blow on this end, push the ball out of the way, and get it to go.
I would blow my ears out trying to do that. There's just nothing.
I can flip it the other way. Nothing. It's just stuck in that closed position
so that's why we can't get any fuel and why the Hummer isn't running.
-Can we temporarily bypass that or is this like a necessary component of operation?
-They put it in there for a reason, I'm sure. But I think on the temporary we could put it in.
We could also try to free it by chemical or compressed air means.
Ideally you just replace it. I wouldn't put it back in or trust it. But yeah, we can bypass it.
-The last thing we're going to try to do before we crank this thing, is the glow plug controller,
and it is connected to the smart start box that we have up under here. But when we tested it,
the...it actually sits right there in the engine...the pins on it weren't working correctly.
So we're just going to replace the whole thing but we do have to pair it or we have to buy
one that does match with the smart start box that's underneath the steering wheel. And what
Brian tells me is that this plug right here has a temperature sensor on it so that when the glow
plugs are hot, this can tell and it won't keep heating up the glow plugs over and over again.
-It's basically where the coolant is.
-So we have some Teflon tape down at the bottom of that to help seal it.
-There it is – perfection.
-Done. Now we can cap it. Alright. Wait light's on,
wait light's off. [Engine sounds] Nada. [More engine sounds]
So I think we finally found the problem. So this right here is the ejector and inside of
the injector is actually a bunch of metal and rust and that's not supposed to be there. It's actually
supposed to look like this, you know, clean diesel fuel. But let me tell you what I think happened.
So I think ultimately what happened was when I got the Humvee, it was running
obviously, but then it sat for so long and the fuel line got blocked.
And so when that fuel line was blocked and I kept on...I kept on turning over
the engine, and so multiple things went wrong. When I connected my battery charger I did fry
the smart start box which did fry the glow plug, so multiple things were happening.
But ultimately it was our fuel line issue that caused the failure of the ejector pump.
-So the ejector pump is a distributor ejector pump and it was rotating and it wasn't having the
diesel fuel in it and that's what lubricates it. That and the same thing happened on the
Perkins series on my videos where the previous owner had cranked it
a bunch of times and it caused the ejector pump to get all chewed up.
-Which we did.
-So that chewed up glitter is what you see in the top of the ejectors. That's evidence of that.
-So our options are: replace the whole fuel ejector pump system which is a fairly in-depth
operation. Or, scrap the whole thing and just take everything out, which I think is what we're going
to do. All of the projects we did up to this point getting this thing working are probably
all valid and probably all worked, we just ran into the ultimate roadblock that is unsolvable.
So if someone did want to replace the injector pump, how would they go about doing that?
-You need to mark your timing on it because, like I say, it's a distributor. But you take off
your...you take your filter and your intake boot, take off the intake manifold and then
you'd have access to get all the lines off the back of the injector pump.
So you've got 9 lines, and then your leak off lines on the top, a couple of plugs,
and then there's three bolts that are 12 point, and then slip it out and slip in the new one.
-We're not going to do any of that. It was a fun project.
I learned a lot about diesel engines and Humvee's in general, but we're going to turn
this into something else. Anyway, I'll leave a link for Brian's channel right here on the
screen and down in the description. Thanks a ton for watching and I'll see you around.