Failed Lifter noise, for those who know..

[john8662]

I think I have a failing lifter somewhere on the drivers side bank on my truck. I just watned some input from those that had lived with a bad lifter and finally got to find the culprit. The reason I think I have a lifter problem is that the truck was parked for about 3 weeks sitting in the garage. I cranked it up last night and it fired right up, but then started missing bad and making a metalic knocking sound. I reved it up, it would go away and return back at idle, and then suddenly it disappeared all-together. I have had it do this in the past, but I figured it was fuel system, never could track it down, it's only when it sits for weeks. After startup I went for a 30 min drive, still have the loping idle. So I'm at either New injectors (currently 30k on remans) or pull the engine and do a lifter job.

Anyways, just wanted some input on symptoms. I've listened to this thing running with a steth, no dice (I don't have a trained ear for this noise). I also recently had the valve covers off and couldn't find anything obvious, no lower pushrods than the rest, etc.

I guess I want some confirmation, before I tear into yet another project.

[crew84]

I would do the 'old bleed the injectors' routine while it is running. It will at least show you what cylinder and maybe it is just air.

[john8662]

I've got everything really good and tight and aligned as best as possible when replacing the IP, etc. I've also tried to open one injector line at a time with it running, I haven't been able to tell much doing that. Each injector seems to be contibuting to the system equally. This truck has been a real challenge in this area. As far as the idle problem, I sent the old injection pump to Accurate Diesel and had it run on the stand, it came back with a perfect clean bill of health. The old pump and the new one behave the same. The injectors were pop tested, and tested good, cold.

Given the rapping at cold start when sitting for weeks, I'm thinking maybe its a lifter that has to pump up, but doesn't quite get pumped up, just enough to not make noise but still have the lope. This truck is my favorite, but it's been a real challenge...

[198662T]

Any luck with doing a compresion test ? My 6.2 did the same thing after being apart and the first restart. I found the #3 intake with a piece of material in the oil inlet in the side of the lifter. I removed it and the miss went away. (thank goodness)It looked to be a pieces of shop rag. Another lesson in clean your parts and get some sleep. Hope this helps.

[dieselbegreat]

I pulled off the valve covers to check the valve action only to find that more than half of my pushrods were bent. Also, it seems that if noise is coming from the one side, the problem is really on the other side. :D

[arveetek]

Originally posted by dieselbegreat:
Also, it seems that if noise is coming from the one side, the problem is really on the other side. :D That was my experience as well. I was certain my lifter tapping was coming from the driver's side. Turns out the failed lifter was on the passenger's side.

I found my failed lifter by turning the crank until the valves were closed on #1 cylinder. I checked to make sure the pushrods and rockers were snug, and then moved on to the next cylinder in the firing order. When I got to #4, I found the exhaust rocker would tip way back off the valve, and the pushrod would push way down into the lifer. That was my failed lifter.

Mine didn't seem to affect the way the engine was running. I didn't notice any stumbling or anything. Just an annoying ticking noise.

Casey

[CleviteKid]

Good tip, Casey. Jim should add this evaluation method to the On-Line Troubleshooting Guide. As MP says in the closing comments section:


If you've solved a particularly difficult repair problem, performed maintenance not talked about here, want to correct something that appears in this guide, or have seen an unusual situation with the GM 6.2L/6.5L diesel engine, please forward a complete description of the remedy to me and I'll try to incorporate your information into a future edition of the The 6.2L/6.5/ Diesel Troubleshooting Guide. If the information you provide is of a substantive nature that is not addressed in this Troubleshooting Guide, you may qualify for a FREE copy of a current or future edition. At a minimum I am copying this thread to my hard drive to save Casey's good idea.

Dr. Lee :cool:

[john8662]

I found my failed lifter by turning the crank until the valves were closed on #1 cylinder. I checked to make sure the pushrods and rockers were snug, and then moved on to the next cylinder in the firing order.Casey,

Sounds good, except one thing isn't clear, when you said that you moved on to the next cylinder in the firing order, do you mean you rotated the engine again? Or, did you just go to the next set of valves in the firing order w/o rotating the engine?

[arveetek]

Originally posted by john8662:
Casey,

Sounds good, except one thing isn't clear, when you said that you moved on to the next cylinder in the firing order, do you mean you rotated the engine again? Or, did you just go to the next set of valves in the firing order w/o rotating the engine? I rotated the engine until the next piston in the firing order was at TDC and both valves for that cylinder were closed. It's the same procedure one would use for adjusting the valves, if these engines had solid lifters. But I'm sure you've done this on a gasser or other diesel engine with solid lifters.

Casey

[john8662]

Casey,

Actually this is the first time messing with lifters and setting valves. I've never had to work on a SBC gasser setting valves, although I am aware of the procedure. I've always admired the simplicity of the 6.2 design verses the gassers when it comes to intake, valves, etc. !!! Thanks for the info, I'll be working on the truck soon, probably just after I get the 6.5TD running again.

[More Power]

This subject (lifters) has an unusual significance, mostly because The Diesel Page came to be, in large measure, because of a single collapsed lifter.

As a youngster and teenager, I wrenched on all sorts of mechanical things, from lawn mowers to Harley's to a string of classic Chevy cars. Then I grew up, got married, joined the Navy - went to school, reentered civilian life, went back to school and worked to support my family. All during this grownup time, I didn't wrench much. That is, till my 6.2 diesel began making a disturbing sound, and I visited a longtime diesel garage to have them make a diagnosis. It's a diesel, I thought, got to have a diesel mechanic look at it. Huge mistake.....

After revving the crap out of the poor old 6.2, and installing new injectors and glow plugs (and $250 in labor), he claimed the engine had a bad rod bearing - would cost about $4K to fix......

I was bummed. To save money, I pulled the engine, and carted it off to a local performance engine shop. I mentioned when I dropped it off that I was curious to know what was making the sound in the engine. A couple weeks later, I learned the engine had a collapsed lifter. :( That's all........ But they were already into the machining and rebuilding, so ya gotta do what ya gotta do.....

It wound up costing me about $3K to get the engine rebuilt and back into the truck. All for a single collapsed lifter.....

Of course all during the rebuild process I learned volumes about cracked heads, head gaskets and a wide variety of other stuff that would have saved me a bunch of money if I'd known more about the engine.

Those early 1996 web pages discussed all that I had learned up to that point in time...

MP

[john8662]

Update, I pulled everything apart and pulled the valve covers and went cylinder to cylinder when the valves were closed for that preticular cylinder and checked for slack. I found two lifters that were bleeding down, thats where my nasty knock was coming from at startup!

Now the bad..

I installed a whole set of lifters packaged under the Melling name (figured they would be good) with the engine in the truck and with the heads on. What a huge chore, but I figured a way to do it that worked well enough to get them ALL done.

I got the engine back together, this took the whole weekend, the whole process. Started it up ran great, no knock, very smooth idle. Then I went for a test drive around town, about 30 miles. Then got a wild hair to take a 130 mile one way trip to a nearby town to see if it's really fixed or not (idle wise).

Nope, got there and started getting the lifter tick of death, great! Now I'm aways from home and it's acting up, turn back and head back. Throughout this whole run I noticed that I'm a little underpowered, although oil pressure and water temp was completly normal (40 psi oil hot idle 55 @ 2k and 185* temp).

Got back home, whew, still has the tick, really noticeable at 1k and up. The next couple of days the truck has been parked, I called some local diesel shops and see if they have had a bad batch of lifters, nope. One shop suggested draining on 1qt of oil out and adding 1qt of transmission fluid and seeing if that would help clear a sticking lifter. I'm not a fan of diluting my oil, so this means I get to tear it down again...

Last night I did it again, took it all back apart. I then rotated the engine over listening for noises, I heard a click, then i found it, first on #7, I was able to push the rocker into the lifter, but not much. Kept rotating the engine over trying to find more, I found two more that were not pumped up. Drats! I guess I'm gonna be pulling em all again.

So, I pull them ALL out and I found 7 of the 16 didn't pressure up, and were still springy. Thats pretty bad odds, nearly HALF of them no good! This sucks! Anyways, right now I'm going to return them, they have a 3mo warranty (I see why) :mad:

There is really no rhyme or reason why it's this way, there were bad ones on both cylinder banks. oil was getting through the pushrods all the way to the tips of the rockers, so I know they're getting oil.

Anybody got a recommendation of a Brand of lifters to use? The Melling ones don't work, and are a different body style (in appearance) than that of the factory GM lifters (pics to come).


I'm bummed, too much work for too little joy. Now I'm out a set of intake gaskets, RTV 7qts oil and filter, etc.

[Turbo Al]

John,
As a sidenote I have run one quart of ATF for lifter noise with good results. This was on my 6.5 when the noise started @ 100,000 miles and after the ATF treatment it ran approx 20,000 miles before it needed it again. I just put the ATF in for approx 300 easy miles (no towin) and then drain the oil and put new oil & filter in. For the most part I did it when it was in need of an oil change anyway. In no way did it damage the engine because it ran for 80,000 miles more (still runs) with no ill effects.
Al

[More Power]

The book says that before installation, to place each new lifter in a bottle of 10W oil, then push the plunger to pump oil into the new lifter.

Also, some engines are stamped in the vicinity of the lifter galley with a mark (near a lifter)indicating whether it is oversize (I've yet to see one though). I suppose this means an occasional lifter might be oversize if the bore was a little too large for a std size. This is why the book says to always install used lifters back into the same hole they came out of.

MP

[john8662]

Jim,

Thanks for the hint. I've got the 6.2 manual and did remember reading that and thinking the same thing. I wasn't able to find the marking on the block anywhere for the OS marking for lifters. I looked at several of the old lifters looking for the marking on the lifters themselves as the manual said they would be on them. I'm going to go out to the garage this evening and wash them all back down and see if I can find out if just a few were OS by the markings on the lifters. I still have them sitting in zip loc bags still in an order that I can rememeber exactly which hole the came out of.

When installing the lifters (both times) I couldn't find any loose, they all fit about the same.

I've talked to Benny at Avant at length about this, and we're both unsure what the problem is. One thing that I can check the next time it's apart (when the engine will be on the stand this time) I will check with a straight edge the length of the valve stems. Seems I might find some that are not the same, and that could cause the ticking too. I don't know if the 3rd set that are installed currently are having the same problem as the Melling ones did. I need a weekend w/o picking up a wrench though, so it's gonna be awhile till I tear into it again..

[john8662]

Another tidbit. According to my manual 'The 6.2 Liter Diesel Engine' that I've got dated '88

"Prime new lifters by working plunger while submerged in new kerosene or diesel fuel. Lifter could be damaged if dry when starting engine

Coat the roller and bearings of lifter with 1052365 lubricant or equivalent"

I followed this advice for the first set of lifters I installed into the engine. I substituded the lube on the roller and lifter body for Mell-lube, usually used in cam installations.

The second set of lifters boxed under the SBI name that I was told were made by Eaton, are installed currently and I primed them with ATF, thought that would make a better substitution than the fuel, same coating routine with the Mell-lube.

I talked to some local diesel shops about what they do with lifters. The responce was what I figured I'd get, just install them with some lube on the roller and squirt some oil on them after you've got em in. They reported no lifter problems. Somethings up with this preticular block, I'll report back if I find any OS lifters out of the original bunch.