Dead 6.2 in Rally Van; Journey Begins

[jogl]

Well, my Rally Van died in June and I finally have a little time to figure out what is wrong.

I was just driving along and it died. It would restart (with the pedal on the floor), but run very rough, like it was only running on half of the cylinders. As I recall, lots of smoke, gray I think.

I'm pretty sure that it is not a fuel supply problem. I bypassed the whole fuel system and ran an intravenous feed direct to the IP and no change.

So, next step is to check compression. But, as an unfortunate few of you know, a few of the injectors are in nasty places in the dog house and under the AC compressor. First question: are there any tricks, tips, etc for getting the injectors out?

Right now it looks to me like the AC compressor has got to go. Ohhhh.........

Thanks,
JP.

[DmaxMaverick]

A compression test is normally done through the glow plug holes. You could do it through the injector holes, but that seems like more work than it's worth. You'd also have to locate an adapter to fit. You can easily fab an adapter from an old glow plug, or just buy the adapter. Most tool suppliers have them.

[jogl]

Oh ya, I forgot about the glow plug holes. I've been working on DI engines lately. With any luck all of the glow plugs will be easily accessible.

Time to go out to the shop for another look.

I have a diesel compression checker with a bunch of adapters so hopefully I won't have to do any improvising.

Thanks,
JP.

[john8662]

Could be failed flexring in the injection pump too.

But a compression test (if coolant or blown head gasket) is suspect can't hurt.

J

[jogl]

How can I check the condition of the flexring? Does the IP have to be removed and dissembled?

Thanks,
JP.

[john8662]

Pump comes off and goes to a pump rebuilder...

[jogl]

I finally found time to check the compression. Looks like the head gasket blew out between 6 and 8. Compression was 360 to 420 psi on all of the other cylinders and <100 psi on 6 and 8.

Is this a common failure?

After the failure of the engine I could start it, with the accelerator at full, and it would shake and smoke and sound horrible, just barely making 1000 revs. Does that sound familiar to any of you who have had a head gasket fail between two adjacent cylinders?

So, I am hoping to be able to change the head gasket in the van. Anybody here done that before? Any hints. Getting the glow plugs out was a chore, I am afraid that getting a head off will be much worse.

Good Day,
JP.

[DmaxMaverick]

While I wouldn't call it a "common" failure, it is one of the least uncommon suspects. Your conditions/symptoms sound about right for a 6-8 gasket failure, and you compression test results indicate that.

I don't know if you can or should remove the head(s) in a van, but if there's room, and the rest of the engine is healthy, I'd try it. I've done several in pickups, but never a van. It's a big(ger) job to pull an engine in a van. If you need a little extra clearance, you can remove the engine mounts and lower it some.

[jogl]

I got the head off and I can see no evidence of head gasket failure. I sure am glad that I double checked those compression readings this morning before I started taking it apart!

But, what now?

I'll sleep on it and check the valves and cylinder walls over carefully in the morning. But valves and ring failures don't really explain the sudden death that the motor experienced.

Something else that I should have done, but didn't, was bar the engine over with the tappet cover off but the head still on to check that the valves were working properly. Has anyone ever had a cam shaft break?

Any ideas are appreciated because right now I am stumped.

JP.

[diaric]

camshaft, unlikely and you would probably loose oil pump drive. check if the plastic button on the rocker shaft, if it broke off those rockers might not be operating the valves on those 2 cylinders

[jogl]

Upon closer inspection:

The plastic buttons are there and appear to be intact.

The head appears to be in decent shape. Valves don't look too bad.

Cylinder bores are at original diameter (3.976" or 100.0mm just using dial calipers at top of bore. Cross hatching is gone and glazed but I have seen much worse running.

Cam shaft is turning although I haven't definitely determined that the timing is correct.

Before I take too much more apart what else can I check?

Thanks,
JP.

[jogl]

I'm trying to think of other things that may have caused the sudden death that my engine died. A bad IP is the first thing that comes to mind, but that does not explain the low 6 & 8 compression readings. Of course the low compression may have been there before and I just did not know. It seemed to be running fine to me. I only drove the van for 2,000 miles before it quit (it has 245,000 on it).

I'm beginning to think that I will have to take the motor out and rebuild it. Nuts!

Well, I guess I'll take the front cover off and check the timing chain and check the IP shaft to see if it feels like it is broke.

All advice is welcome.

Thanks,
JP.