Disassembly for rebuild has started.

Found evidence that every cylinder had burned some coolant. I'm also concerned seeing some rust where the oil passes through to the rocker pedestal stud. I hope it hasn't diluted the oil very much or done any damage to bearings and other parts but I'm going to change it anyway.

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Bummer. I agree with the others, 625 and fresh surfaces should be trouble free with your ve.
 
9724VF350 said:
In 5+ years my best customer hasn't had to adjust his BHJ tool for fire ring diameter on OEM gaskets. I'm both a Cummins and Mahle/Clevite/Victor dealer. If you didn't take it out of the OEM Cummins package, it's not a OEM gasket. There are differencess, I don't care who makes them. We learned all this crap the hard way years ago.
Mahle supposedly also makes Cummins pistons, yet they will score quicker than a OEM piston will.

Either you're you're using Victor gaskets and calling them OEM, or your machine shop fukked up and is passing the blame to the gasket.
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There is a local engine builder who builds probably 50-60 Cummins engine's a year, who this particular machinist has always done o ring grooves for. I've also always used this machinist for our own personal o ring grooves.

Now in saying that.... we have no idea why Jim's is the first of where the o rings were caught being the issue.

I did a lot of investigation into this to figure out why...... But there were 2 issues. Machinist had cut a spec into an original oem gasket probably 5+ years ago. Where the outside of the fire ring was (I don't have it in front of me, but I bet Jim also has these dimensions..... 4.56)?

Over the years (we pulled gaskets out of a ton of old engines down at the engine builder's shop I had mentioned above). And the fire ring o/d diameter has progressively gotten smaller until it is where it is today.

The 24 valve gasket used to be wider and a couple years ago had an update in the Cummins bulletin about changing the fire ring for better sealing.

However.... that machinist did cut those o ring grooves outside of BHJ spec. Where he apparently cut them to his original gasket x years ago. So.... he messed up twice essentially.



Now, the above is in no way excuses but more of a .... explaining what Jim was talking about as we were tying to figure out why is this the first one? That part we still don't know. My current engine has the same cut, and I have no issues with 425s and raised compression.



However, none of that actually matters and we're sending Jim a new head. Currently waiting for the port/polish guy to finish up so he can get back on the road.


Eric
 
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Yeah some people just can't listen. Ask for advice, then tell everyone they don't know what they're talking about.
 
What the phuck is that about? I never said he or anybody else didn't know what they're talking about. I used the VR gasket from the Mahle kit initally because it's what I had. The 2nd gasket I put in it was straight from Cummins and it leaked just the same as the Victor Reinz. Is one from Cummins not OEM?? I don't have control over who makes their gaskets.

From what research Eric and I have done, it all points to the o-rings.
 
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Hello jimbo486, I have followed your build with interest, very nice & painstakingly done!

Let's put aside your head gasket issues for now & talk about the machining.

When the head is o-ringed, placement/machining of o-ring is better off being closest to the inner circle of the head gasket fire ring, than the outside.

In your case it was lining up at the outer most side of fire ring of head gasket.

You have many excellent & reputable shops around you, some are on here as well.

Keep us posted & hope the end result turns out great no matter which route you go :Cheer:
 
If you had followed it like you said, you'd have seen that we had already come to that conclusion and that I never once insisted that it was certain to be a gasket problem other than the fire ring diameters changing. Which initially we thought only could have been partly a reason.

It was then stated above that the jig was adjusted beyond what the specs were supposed to be for the o-ring grooves.

Thanks for trying.
 
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I tried to be gentle & encourage your anal "build" , but you're a fool, pretty obvious when you post about anything technical.

It is most certainly a cost cutting gasket issue that your unscrupulous middleman Hungry Weasel tried to save a couple bucks on.

Learn from your betters here, and "unphuck" this mess at his reputable shop.

Competition Diesel.Com - Bringing The BEST Together - View Single Post - victor reinz head gasket

I believe 9724VF350 and Fatty warned you repeatedly about the "non gasket" issue.

Squeak back in this thread if you want details of how a machine shop with a "jig adjusted beyond specs" is substandard and shoddy. Period. Can't Weasel out of that one. No matter how much free vaseline you get with your THD parts.


jimbo486 said:
If you had followed it like you said, you'd have seen that we had already come to that conclusion and that I never once insisted that it was certain to be a gasket problem other than the fire ring diameters changing. Which initially we thought only could have been partly a reason.

It was then stated above that the jig was adjusted beyond what the specs were supposed to be for the o-ring grooves.

Thanks for trying.
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There's an issue somewhere that doesn't seem to be related to the head or gasket whatsoever. Maybe I'm wrong as far as the gasket goes after seeing the recent thread about repetitive gasket failures others are having. I posted in that thread but didn't want to cause much of a derail since these symptoms are isolated and aren't very similar to the other failures.

After installing the replacement head (no O-rings) and another new standard gasket, it still weeps from the rear after filling the system. Again, just head pressure alone. Hadn't started the engine or even cranked it to bleed the injectors.

I'm not understanding how something like this can happen so suddenly. It never leaked a drop prior to the rebuild, other than when the head gasket blew out at #5. But never from anywhere else. After the rebuild, it leaks. WTF? The machine shop that built the shortblock assured me the deck was good. I checked it for myself when I put the 2nd gasket in it. With a short level (closest thing to a straight edge I have) rolled up on its very edge, I couldn't get a .003" feeler gauge under it anywhere on the deck, checking every single inch front to back, side to side. That dimension is the amount Cummins says the deck cannot exceed.

I inspected both dowel rings for any burrs or oddities in shape. Cleaned them up with 120grit sandpaper and attempted to chamfer their tops. Measured them with calipers and compared that dimension to the bores in the head. Both matched. Both heads looked and felt to have been sitting evenly on the gasket under their own weight. If the machine shop said the deck was good, I'd assume they didn't pulled the dowel rings at all.

Should the machine shop have surfaced the deck out of good practice so that both it and the head surface would be true and clean when sandwiching the gasket? They told me it was standard practice to bore the cylinders out knowing that they'd start over with good and clean bores. I plan to talk to them soon about this to see what they have to say about it. I don't see any reason to even bring up the issues with the o-ringed head, as it doesn't seem to be related.

Whatever the diagnosis, my gut tells me that it's gonna have to come out again in order to be fixed correctly. I just don't know if I have the funds it might take.

Has anybody ever heard of or had personal similar issues after a rebuild? I'm at a loss and damn near about to pull all my hair out. At the moment, it's been a year since I parked the truck to start this rebuild and have only put 150 miles on it from when the first gasket finally sealed up, to when it started leaking again.
 
So you don't KNOW the block is flat in other words. A precision ground straight edge and a level are nowhere in the same ballpark. I would be surprised if a level WASNT warped .003" or more. I would have pulled the entire thing out and taken it back to the machine shop. Pay them to finish building the engine with the understanding that it has to at least hold coolant and oil through the first test drive. If they refuse to assemble it or take a second look at it then take it somewhere else and send them the bill. They should at least check it out.

I struggle with being very "cheap" at times to save a buck myself. One of the best pieces of advice I have ever heard is that the cheapest people end up spending the most money. Take the engine somewhere man. It is obvious something is wrong. If the head were perfect and the block were perfect you would not leak coolant during fill up regardless of which gasket was used.

Nobody is calling you dumb, nobody is calling the machine shop dumb. People make mistakes. If there is indeed an issue with the block just present the facts to the shop that did the work. Any decent shop will make it right. You have everything well documented. Show them what you have done and what is happening.
 
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this may be a stupid question, but there are no surprise water passages in the new casting cylinder head? blocks and head castings change over the years in some motors.

i've never heard of it being an issue with a cummins but when I put a 4.0 head on 4.2 (jeep I6) i had to jb weld some extra water passages closed.

are we banking on the "new" head having a true surface or was it decked before install? sorry, didn't read whole thread.

can't just be the gasket. even the cheapest gasket will seal 2 true surfaces.
 
The OEMs are not known for having great heads... just an FYI. Most of my experience is with the larger stuff but I dont imagine Cummins gives special attention to their light duty market.

It sounds like a $50 straight edge and a trip to the machine shop would go a long ways for you.
 
zfaylor said:
So you don't KNOW the block is flat in other words. A precision ground straight edge and a level are nowhere in the same ballpark. I would be surprised if a level WASNT warped .003" or more. I would have pulled the entire thing out and taken it back to the machine shop. Pay them to finish building the engine with the understanding that it has to at least hold coolant and oil through the first test drive. If they refuse to assemble it or take a second look at it then take it somewhere else and send them the bill. They should at least check it out.

I struggle with being very "cheap" at times to save a buck myself. One of the best pieces of advice I have ever heard is that the cheapest people end up spending the most money. Take the engine somewhere man. It is obvious something is wrong. If the head were perfect and the block were perfect you would not leak coolant during fill up regardless of which gasket was used.

Nobody is calling you dumb, nobody is calling the machine shop dumb. People make mistakes. If there is indeed an issue with the block just present the facts to the shop that did the work. Any decent shop will make it right. You have everything well documented. Show them what you have done and what is happening.
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Thanks. You're right, I don't know for certain if the deck is good or out of spec just enough to leak. It's nuts that it happened out of nowhere only after the rebuild. I don't feel that I was cheap in anything I did to this motor. I'm of the mindset that you get what you pay for. I never like to take shortcuts or bandaid anything together unless it's to limp it home.

zfaylor said:
The OEMs are not known for having great heads... just an FYI. Most of my experience is with the larger stuff but I dont imagine Cummins gives special attention to their light duty market.

It sounds like a $50 straight edge and a trip to the machine shop would go a long ways for you.
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You'd think they would magnaflux their heads to check for cracks at the very least. Both heads were surfaced because even from Cummins, they were found to be slightly warped but probably within the amount they specify. I think the heads can have something like .012" at most. Regardless, I preferred it to be flat.

j.fondler said:
this may be a stupid question, but there are no surprise water passages in the new casting cylinder head? blocks and head castings change over the years in some motors.

i've never heard of it being an issue with a cummins but when I put a 4.0 head on 4.2 (jeep I6) i had to jb weld some extra water passages closed.

are we banking on the "new" head having a true surface or was it decked before install? sorry, didn't read whole thread.

can't just be the gasket. even the cheapest gasket will seal 2 true surfaces.
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No water passages that looked odd or out of place to me in either of the heads. I'm not positive if it's leaking on both sides of the gasket but best I can tell, it seems to be weeping between the block and gasket. Like Eric said, both heads had been surfaced.

Any chance the block could have cracked between that rear stud hole and the coolant passage from torqueing the studs or even the bolt bore itself cracking in the bottom and allowing water to escape through it? I've never seen anything about that happening though.

The plan is to pull the motor, of course. I just need to save up some cash to cover repairs before they can be done.
 
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jimbo486 said:
It's nuts that it happened out of nowhere only after the rebuild.
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likely because the block and head kind of "warped" together if you get what i mean. then you introduced a true surface(head) to an untrue surface(block) and voila, you have a leak.

i hate doing shyte twice. i just installed my nv4500 for the 2nd time in 30 days, so i feel your pain.

you just gotta hope that in the end, all the money, blood, sweat, and beers was worth it.
 
j.fondler said:
likely because the block and head kind of "warped" together if you get what i mean. then you introduced a true surface(head) to an untrue surface(block) and voila, you have a leak.

i hate doing shyte twice. i just installed my nv4500 for the 2nd time in 30 days, so i feel your pain.

you just gotta hope that in the end, all the money, blood, sweat, and beers was worth it.
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I get what you're saying and it makes sense. I seem to recall briefly seeing it mentioned in Will's (Big Blue) ongoing thread. Wish I had just told the shop to surface the damn thing and I'd figure out what gasket to put in it after measuring piston protrusion.
 
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Maybe a crack? Maybe some one got carried away cleaning the gasket surface and made a low spot. I have used victor, felpro, and mcbee gaskets with o-ringed heads with no problems. The only gasket I've had problems with was a gasket in a cummins package from eBay. Just thought id add that please let us know if you ever resolve this issue. I don't like to machine things that don't need it so your machine shop was probably right to leave the deck surface alone not saying they didn't miss something but it seems like a lot of people who don't even know how to use a straight edge are quick to say everything needs to be resurfaced again I'm not saying this isn't the problem but I wouldn't be mad at the machine shop unless it turns out the surface is out of spec.
 
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