Liner Height

[Mr Hagg]

Yes this is really been an eye opener for sure. The rings were also A problem man this thing would have started using oil in no time. I guess if it was to been with mandate still on i guess carbon could have fill the gaps lol... Sorry to hear about your engine Starlight I wish i Had known this info before I would have went a different route. I spent 11K on just the block, pistons, and crankshaft. This is their version of a short block... Only to have to spend even more to get it right. Lucky for me Rawze came and cut the bore and save me $$$$.... Cause I have qouted this job so I was at a lose already but I feel so much better about it now.

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[Starlight]

(01-27-2017 )Mr Hagg Wrote:  Yes this is really been an eye opener for sure. The rings were also A problem man this thing would have started using oil in no time. I guess if it was to been with mandate still on i guess carbon could have fill the gaps lol... Sorry to hear about your engine Starlight I wish i Had known this info before I would have went a different route. I spent 11K on just the block, pistons, and crankshaft. This is their version of a short block... Only to have to spend even more to get it right. Lucky for me Rawze came and cut the bore and save me $$$$.... Cause I have qouted this job so I was at a lose already but I feel so much better about it now.

Just to clarify, Mr Hagg, this is not my own engine. I own no trucks, I'm a diesel shop. The real kicker is this engine has less that 65,000 kms since it was installed. Im pulling the pistons and liners now so I will post what I find with the rings. Customer is not happy.

[Rawze]

(01-27-2017 )Starlight Wrote:  This liner issue thread is very timely. I currently have a 2009 871 in the shop with the coolant system pressuring up. It was installed in this truck a year ago as a recon crate engine from cummins. I just finished pulling the head off to repair and found the gasket burned out on cylinder 4 exhaust side and cylinders 2 and 3 very close to burnout as well. Liner protrusions on this engine on the cylinders not burned out is .010 thou. How terrible can it get. The burned out ones i didnt measure but have no reason to believe they were any different before they burned out. This is a high horsepower 2919 CPL and cummins built it with .10 thou liner protrusion. This truck is demandated so he didnt even try for warranty but still goes to show that cummins builds these things to barely make warranty and then need to be inframed. This engine probably had varying liner heights brand new from cummins just like the one Mr Hagg is doing now. Very poor on cummins part but what can we do, I'll be cutting this block so there will be a .014 or .015 protrusion on the liners afterward.

High HP and factory height liners is not a good combo.

Boost above about 36-38 on it if it has the big turbo and bigger CAC, etc. and/or timing advance too high can cause it too on high hp engines.

http://rawze.com/forums/showthread.php?t...5#pid11615


Just some things to avoid.

Personally, At max torque, I like to see them with a final injection mapping at around 4-6 deg. max and about 36 psi boost or so to help keep vibration down and reduce risk of detonation.

[Starlight]

I pulled all the liners and pistons. If the piston was devided into quarters then all the ring gaps would have been inside of one quarter. A couple of them had gaps lined up with each other. 1 piston had the top ring and and the second ring opposite of each other. Very poorly assembled to say the least. Then I cleaned up all the counterbore ledges to inspect and found all of them in mint condition with those tiny grooves that are there from the factory still nicely visible. The liners had the captive brass shims on them and they were obviously a bit worn from movement. The height from the deck to the counterbore ledge was a bit off at 4.7255 avg instead of the standard 4.724 spec. Basically the gasket had burned out because the protrusion too low and not because of fretting. Again very poor on Cummins part. The block surface is in very good shape with no warping or distortion. Block varies .001 thou from the front to the back which I don't think is something to be concerned about.

[Rawze]

(01-28-2017 )Starlight Wrote:  I pulled all the liners and pistons. If the piston was devided into quarters then all the ring gaps would have been inside of one quarter. A couple of them had gaps lined up with each other. 1 piston had the top ring and and the second ring opposite of each other. Very poorly assembled to say the least. Then I cleaned up all the counterbore ledges to inspect and found all of them in mint condition with those tiny grooves that are there from the factory still nicely visible. The liners had the captive brass shims on them and they were obviously a bit worn from movement. The height from the deck to the counterbore ledge was a bit off at 4.7255 avg instead of the standard 4.724 spec. Basically the gasket had burned out because the protrusion too low and not because of fretting. Again very poor on Cummins part. The block surface is in very good shape with no warping or distortion. Block varies .001 thou from the front to the back which I don't think is something to be concerned about.

WoW!. That is the second factory reman engine I have heard about with rings having an incorrect alignment.

Just throwing this out there for others following this thread ...

(this is not recommended, just stating some info here)...
- With the mid-stop cut at 4.7255", this will usually put the newer liners right at 0.010". Typical height from factory. Sounds like it was the correct depth for factory any ways, though I would not have accepted it there. The minimum cummins says is is 0.007" liner height. 0.010" was still in spec, but we all know that is not good enough. I would not want to run it that way with the brass shims on the ledge myself.

===

At least you are on the right track with it but I would check VERY VERY carefully, the under-side of the head for wear where the liners were dancing. All it takes is a 0.001" - 0.002"+ impression on the underside of the head and you are looking at uneven liner compression and problems all over again.

[gearhead]

This brass shim info is very interesting for sure.

[Starlight]

(01-29-2017 )Rawze Wrote:  

(01-28-2017 )Starlight Wrote:  I pulled all the liners and pistons. If the piston was devided into quarters then all the ring gaps would have been inside of one quarter. A couple of them had gaps lined up with each other. 1 piston had the top ring and and the second ring opposite of each other. Very poorly assembled to say the least. Then I cleaned up all the counterbore ledges to inspect and found all of them in mint condition with those tiny grooves that are there from the factory still nicely visible. The liners had the captive brass shims on them and they were obviously a bit worn from movement. The height from the deck to the counterbore ledge was a bit off at 4.7255 avg instead of the standard 4.724 spec. Basically the gasket had burned out because the protrusion too low and not because of fretting. Again very poor on Cummins part. The block surface is in very good shape with no warping or distortion. Block varies .001 thou from the front to the back which I don't think is something to be concerned about.

WoW!. That is the second factory reman engine I have heard about with rings having an incorrect alignment.

Just throwing this out there for others following this thread ...

With the mid-stop cut at 4.7255", this will usually put the newer liners right at 0.010". Typical height from factory. Sounds like it was the correct depth.

The minimum cummins says is is 0.007" liner height. 0.010" was still in spec, though I would not want to run it that way with the brass shims on the ledge myself.

===

At least you are on the right track with it but I would check VERY VERY carefully, the under-side of the head for wear where the liners were dancing. All it takes is a 0.001" - 0.002"+ impression on the underside of the head and you are looking at uneven liner compression and problems all over again.

I am replacing the head, Its cracked in a coolant port causing coolant to form on one of the #6 exhaust valves. And yes there is obvious damage to the fire ring portion of the cylinder head on hole 4 that was burned out.

[superbug]

This is a very good thread for info. Who has the definitive book on how to properly rebuild these ISX engines?
You would think a factory reman engine would have this stuff correctly done. I think it is crap that these OEMs make claims that their remans are as good as new and then turn out you find obvious stuff wrong that greatly affects the life of the motor.

Once again is there a reference manual with these hard learned specs and tolerances?

[Rawze]

Register your engine serial number on quickserv.com -- That is the place you will find anything you need to know outside of the few recommendations/changes when re-building one discussed here on the forum.