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Arlie
10-27-2003, 12:46
A little metal spring clip holds the oil cooler lines onto the engine. Clip fails - oil gone - dead engine. Thank-you GM.

My wife was driving, drove about one mile after she noted no oil pressure. Engine stalled and she restarted twice. A large puddle was on the driveway so it wasn't dry for long.

I replaced the #%@ fitting and put oil back in. Starts OK but no oil pressure showing with two starts, running about 20 seconds each. I know the gauge worked before.

I'm guessing it's fried. Any ideas how to check it out further?

Arlie

PS anyone else have this part fail?

Cowracer
10-27-2003, 13:13
Arlie,

Does it hammer when you start it, or sound otherwise strange? I'd think that if the bearings have opened up enough that you get zero oil pressure that it would make a hell of a clatter.

Any chance of getting a good mechnaical guage on an oil gallery to make sure?

Tim

m-keith
10-27-2003, 14:31
I have a theory about this, but while reading it, bear in mind that I'm a relative newbie. As such, most of my knowledge is theoretical rather than hands-on.

Is it possible that your oil pump lost its prime & perhaps, may even be bad. I've heard of this happening in gassers. Here's what I think is happening: The truck starts & runs for 20 seconds. When you first crank it, the lift pump is powered by a relay; once running, it's powered by the OPS. With no oil pressure, the OPS isn't sending power to the lift pump; so the truck dies.

I wonder how you could go about manually re-priming the oil pump? I could do it on most gas motors, but I wouldn't know how to go about it on a diesel.

Unless it makes bad noises, I wouldn't go pulling the motor until you confirm that it's bad.

britannic
10-27-2003, 14:46
Originally posted by Arlie:
A little metal spring clip holds the oil cooler lines onto the engine. Clip fails - oil gone - dead engine. Thank-you GM.

My wife was driving, drove about one mile after she noted no oil pressure. Engine stalled and she restarted twice. A large puddle was on the driveway so it wasn't dry for long.

I replaced the #%@ fitting and put oil back in. Starts OK but no oil pressure showing with two starts, running about 20 seconds each. I know the gauge worked before.

I'm guessing it's fried. Any ideas how to check it out further?

Arlie

PS anyone else have this part fail? If this engine had a mechanical fuel pump, it would probably be siezed or worse - hopefully it quit running quick enough to save it.

Since it starts, I'm assuming this is from the pre-crank lift pump spool up getting fuel to the pump for about 20-30 seconds worth of running?

Disable the IP, undo the oil pressure sender and crank the engine; does oil spurt out?

YMMV, but there may be air in the passages to the oil pressure sender and switch that prevent them from seeing the true oil pressure. After installing a new oil pump on my engine, it took a couple of cranking sets (@ 15-30 seconds each, IP disabled) before the oil pressure began to register.

I would recommend cranking the engine only, until you see good oil pressure, otherwise combustion forces and heat will indeed swiftly ruin it.

From my experience, the oil pump is self priming, providing it's immersed in oil. If you are installing a new one, it's worth testing it with a drill before installation to see if it pumps properly.

Arlie
10-27-2003, 19:50
Thanks, cowracer, m-keith, and britannic for the replies.
I should have clarified, I shut it off each time after 20 seconds thinking maybe the pump was bad or needed priming.

Doesn't make sense to me though. I first put oil in to find the leak and started it briefly and it made a "healthy" spurt out the cooler line fitting so the pump has oil and pumps at least somewhat.

I was waiting to hear a horrendous rattle and didn't. I had a hard time deciding if there was more than the usual diesel rattle. I don't drive it much and never listened with the hood up before and didn't want to run it long. Anyway nothing dramatic sounding.

So I'm still hoping (even praying) brittanic's idea is it:

there may be air in the passages to the oil pressure sender and switch that prevent them from seeing the true oil pressure

I sure don't want to screw the engine if it isn't already. Can you tell me how to disable the IP? I have minimal experience with these.

BTW, near as I can tell it is a mechanical pump.

Arlie

StephenA
10-27-2003, 23:45
Arlie- I believe your 93 may be identical to my late model 92 mechanical. Great year! Get out the owner's manual and look under the section which describes how to change the fuel filter. It has a subsection & picture on bleeding out air/water. It shows how to disconnect the wire on the injection pump which will prevent the engine from starting when you turn it over... Don't crank too long or too often - let the starter rest (dissapate heat) between 10- 15 sec cranks. How many quarts did you refill with? Was the puddle only a few quarts or all 7?
The hoses are notorious for leaking & dumping oil- Greg at www.lubespecialist.com (http://www.lubespecialist.com) has an upgrade with all new fittings & hoses. How did you fix the leaking fitting - with a hose clamp? You might check your repair to make sure it's passing oil through the lines with no resistance - no oil through the lines means no oil back to & through the engine. My vote is you didn't fry it yet, but the OPS probably has an air pocket under it, (and the oil cooler may have drained out as well, leaving another large pocket). When I replaced my OPS, the gauge jumped around until the air pocket under it moved out. Pulling the OPS & cranking should spurt enough oil out to top off the hole & remove the pocket.
BTW, this is another topic, but has anyone ever researched putting an electric oil pump on a 6.5 that oils the engine before starting? It would help keep the turbo oiled, as well. The cooler lines might be just the place to splice one in easily... I'll email Greg...
Good luck Arlie,

[ 10-27-2003, 11:05 PM: Message edited by: StephenA ]

TJ
10-28-2003, 14:00
We had this very same thing happen to our 98. The cooler line came off, and drained everything. My dad was driving at the time, and quickly shut the engine off. However, lots of oil had drained. To make a long story short....the truck still started and ran once the crankcase was filled with oil. It sounded completely normal. However, there was some major damage discovered once the oil pan was removed. As a result, a new engine was needed.

Arlie
10-28-2003, 22:38
TJ - I'm not surprised. They've got a thin piece of spring wire holding together a critical part for Pete's sake! I'm better off not thinking about it 'cause my BP goes up. I'm afraid to check for metal in my oil - not to that stage yet.

Anyone else out there hear of something similar with the "quick disconnect oil cooler line" that spells quick death for your engine? I may just send a letter of thanks to GM futile as that will be.

Stephen, thanks for the helpful post. Unfortunately I don't have an owner's manual. Bought the truck used after conversion from 454 to diesel. I bought a "fuel and emissions service manual" a while back but now see it doesn't cover diesels :rolleyes: Anyone have a gasser and need a manual?

To answer your questions: I'm using gallon jugs so can't be precise - 3 or 4 quarts first to get it to read low on the stick, brief run - oil spurting - fitting with my "favorite wire spring" replaced new (I'll change it over with Greg's item if the engine's not dead). About 4 quarts to read full. Still reads full after the 2 short runs - oil on stick clean, like it didn't circulate. Original puddle was on gravel - I can only say no less than a quart.

Boy diesel mileage is great, but now I think I had rocks in my head to mess with one.

BTW - With my sour grapes aside, what do you like about the 92 year?

Arlie

Arlie
10-28-2003, 22:43
I forgot to add, my OP gauge doesn't bounce, sits on zero, doesn't move other than the little movement with turning the ignition on and off.
Arlie

StephenA
10-29-2003, 01:55
Hi Arlie,
The 92-93 year has the totally mechanical DB-2 injector pump, so there are none of the much dreaded problems associated with the failing electronic pumps nor is there a need to mount the electronics remotely on coolers. Many folks have retro-fitted their electronic jobs back to this pump, as it is so much more reliable.
Most 92-93's seem to go much farther on stock injection pumps and injectors than any other stock 6.5 year I've heard of. I read about one yesterday that went 450k on the original parts!
Upon research, swapping out & timing the IP is also the easiest & cheapest diesel I've owned (about $650 for a good rebuild, DIY swap).
Parts in general are reasonable & the engine is pretty simple to work on. There is no On Board Diagnostic computer connected to the engine, so a trouble code scanner is not needed (The OBD1 mounted under the hood only monitors the auto transmission, if not manual, & the rear ABS). The $65 Turbo-Master wastegate controller offered by Bill Heath was originally made for our GM1 turbos, & boosts power easily and cheaply. Rebuild your engine if necessary, but hold on to that truck- it's a good one for the long haul and the exact opposite of a lemon.
On the passenger side of the Injection Pump (IP), there is a white nylon connector- disconnect this and you can crank the engine without fuel ignition.
So, let me see, you put in a total of almost 7 quarts, right? So that means it was pretty near empty. Did anyone see a spike in the water temp gauge? Probably not hot yet. Did the revs stay low or did it go much over 2k? Ask the wife, cause maybe it's still not fried.
The OPS needs to see pressure or it shuts off the electric fuel pump that supplies the IP, & the engine stalls or runs weak. Get that air bubble out or replace the OPS, if it's bad (probably ok - it shut you engine down, right?).
Put a strong magnet on the oil pan, slide it over to the drain plug and see what metal you can collect. This will also keep any light metal bits from recirculating.
Got to get that oil pumped through everything & all the air pockets out. You might want to over fill it a little bit, crank it several times with out starting (or maybe actually running it for just a few seconds or minutes will distribute the oil, if the lines are not blocked), & then drain the oil down to operating range before starting again. This should also give you a chance to catch some metal on the magnet, if there is any.
If the engine is damaged, then get another or get this one rebuilt by Avant, & bump it up to 250 HP or so... It's a great truck. They don't make any diesels that simple anymore. Just my $.02.
Good luck

rjschoolcraft
10-29-2003, 03:57
That "cheap little metal spring clip" actually does it's job nicely...as long as it was installed properly. What has happened to you is that the guy who installed it didn't get it seated in the groove properly. If cranking doesn't restore oil pressure, at a minimum I would pull the oil pan and inspect for damaged bearings.

Arlie
10-29-2003, 14:48
Stephen - thanks for a very informative reply. I'll give it a try, and likely I will keep the truck, especially if I can build in some extra power without huge extra dollars beyond the already large expense of a rebuild. The forum is a great thing in terms of finding ways to compensate for factory blunders.

I've read good things about Avant here. Long way from Idaho though. A local mechanic advises to stay local if I need a rebuild in case of problems. Further thoughts in this regard?

Ron, sorry but I can't agree with defending that spring clip idea even if it works well most of the time. I worked on aircraft a long time ago and I know no such idea would be tolerated where lives are at stake. Just because this is not the case with an automobile engine is no excuse for such careless engineering. Convenience is great but this idea is just wrong.
What actually happened is the spring wore grooves in two places where it bears on the retaining ring on the cooler line. Perhaps the spring lost tension during prior removal. I don't care how it happened, it's susceptible to failure and I'll bet lots of engines have failed as a result. :mad: Shame on GM!

Arlie

catmandoo
10-29-2003, 17:57
i just bought a 92 in feb and have over 45,000 miles on it since and at first i had my doubts as i was used to the 84 i still have but other than the glued on doors which i still think i'm gonna attempt to bolt on. THIS THING ROCKS,i'll probaly have it til i die. do not get rid of that truck period.you will regret it

StephenA
10-29-2003, 19:51
I know what you mean, Arlie; there are some other things you find too, but this website has some great work arounds for them. The oil cooler lines are famous for leaking, busting, dumping oil, etc., regardless of the clip (both gas & diesel), so the upgrade from Greg is a good idea even if the clip never failed. The headlight harness is another one, as well as the ignition switch & OPS, etc. But dumping oil is bound to **** anybody off!
catmandoo-92! I didn't know that was your rig! So your door linings are glued on too? I thought it was just a cheap repair on mine. Silly GM-rabbit - tricks are for kids! But what a great truck!