Etech cylinder liner question.

[07cl733]

Hello all, I'm having a bit of trouble with an etech 460 and would appreciate any input you may have. The number 2 fire ring started leaking compression into the water jacket and number 3 looked to be close behind. Liner protrusion is in spec on all cylinders, but some are at the low end. I've read input from other members that said the 460 HP engines work better with the liners set at the top of the .023 to .029 range. I lost a head gasket under this head 200k miles ago, but on the rear 3 cylinders. I swapped heads front to back at that time and the now rear head looks fine, as it did then. My questions are, could the head be the problem, or are the cylinders just too low? Also, is my only option to raise them to cut the counter bores and shim them up? Did anyone ever produce taller liners for the higher horse engines? 

[Joey Mack]

In my opinion. .023" is too low. When I set liners i shoot for .027". You are allowed .002" across the cyl's. So .025" would be the low, and .029" would be the high.  Are you using a sled gauge to check liner protrusion? And pointing in the correct groove at the top. Is the deck flat? 

I dont know of taller liners, an uncut counter bore shelf is around 4.003" deep. This is based off of my own measurements .

[fjh]

12 hours ago, 07cl733 said:

Hello all, I'm having a bit of trouble with an etech 460 and would appreciate any input you may have. The number 2 fire ring started leaking compression into the water jacket and number 3 looked to be close behind. Liner protrusion is in spec on all cylinders, but some are at the low end. I've read input from other members that said the 460 HP engines work better with the liners set at the top of the .023 to .029 range. I lost a head gasket under this head 200k miles ago, but on the rear 3 cylinders. I swapped heads front to back at that time and the now rear head looks fine, as it did then. My questions are, could the head be the problem, or are the cylinders just too low? Also, is my only option to raise them to cut the counter bores and shim them up? Did anyone ever produce taller liners for the higher horse engines? 

You want to be as Joey said  25 or better specially on  high HP engines !! On the first E7 engines the spec was set low and it caused issues like this! I believe the low spec back then was 19 ! Had one that kept blowing rads up and popping water filters! odiously the filler cap was haywire too However! After the second water filter you have to dive in and figure out what the issue really is!

[07cl733]

I am using a quality sled guage and I am going by the manual for the measurement. I haven't pulled the liners, so I guess that's next. I'm looking for a longer straight edge to check the block and heads. I'm probably not getting a clear enough reading with the one I have. 

This motor was rebuilt by the previous owner and may have already had the bores cut. I am curious if you've seen protrusion too low from the factory? Did they ever change production specs as they increased power ratings? 

The motor ran good other than the failed gasket and naturally, I don't want to rebuild it if I can avoid it. In your opinion can I expect any life out of it at the lower end of spec? The truck is 26 years old and a couple hundred thousand more miles might see her to the end. 

Thanks for any help. I know I have a lot of questions and am asking for some speculation. I just don't have enough personal experience with this to make a good decision. 

[fjh]

5 minutes ago, 07cl733 said:

I am using a quality sled guage and I am going by the manual for the measurement. I haven't pulled the liners, so I guess that's next. I'm looking for a longer straight edge to check the block and heads. I'm probably not getting a clear enough reading with the one I have. 

This motor was rebuilt by the previous owner and may have already had the bores cut. I am curious if you've seen protrusion too low from the factory? Did they ever change production specs as they increased power ratings? 

The motor ran good other than the failed gasket and naturally, I don't want to rebuild it if I can avoid it. In your opinion can I expect any life out of it at the lower end of spec? The truck is 26 years old and a couple hundred thousand more miles might see her to the end. 

Thanks for any help. I know I have a lot of questions and am asking for some speculation. I just don't have enough personal experience with this to make a good decision. 

You could try re retorque after a few heat cycles ( Crap shoot ) other than that you got to pull liners check for cracks and shim ! on the cheap a guy could scuff the liners and reuse! Done that ! Mack made us do this under Warranty once and NOT SCUFF the liners It worked oK but I prefer to scuf!

just my opinion!

[07cl733]

Just now, fjh said:

You could try re retorque after a few heat cycles other than that you got to pull liners check for cracks and shim !

just my opinion!

Okay thanks. I did that last time I changed the gaskets and did get 200k out of them. If the bores and liners look good, can they be shimmed .003 or .004? What thicknesses do the shims come in?

[fjh]

3 minutes ago, 07cl733 said:

Okay thanks. I did that last time I changed the gaskets and did get 200k out of them. If the bores and liners look good, can they be shimmed .003 or .004? What thicknesses do the shims come in?

Joey or Heniz would know the shim the shim sizes available ! 2 thou increments Rings a bell for me But havent been there for a few years!   You should clock the liners as you pull them and put them back in the same local if your going to try this! 

[07cl733]

1 minute ago, fjh said:

Joey or Heniz would know the shim the shim sizes available ! 2 thou increments Rings a bell for me But havent been there for a few years!   You should clock the liners as you pull them and put them back in the same local if your going to try this! 

That seems like a good idea, thanks. If I shim the liners, would I put a bead of silicone on the block and on the shim? Or do I just put it on the block? 

[Joey Mack]

Shim sizes are a plenty. Up to .020". 

[Joey Mack]

I put a narrow bead on the liner and on the shelf.  NARROW.... you dont want the RTV to not allow a good liner seat. I also recommend taking a small amount off the shelves with a counter bore cutter, unless you are happy with the depth mic readings at 4 points in each bore

[07cl733]

13 minutes ago, Joey Mack said:

I put a narrow bead on the liner and on the shelf.  NARROW.... you dont want the RTV to not allow a good liner seat. I also recommend taking a small amount off the shelves with a counter bore cutter, unless you are happy with the depth mic readings at 4 points in each bore

I'll get in there and check things out. I may be able to borrow a cutter if needed. Thanks for the advice. This may be a new motor before I'm through. 

[fjh]

28 minutes ago, Joey Mack said:

I put a narrow bead on the liner and on the shelf.  NARROW.... you dont want the RTV to not allow a good liner seat. I also recommend taking a small amount off the shelves with a counter bore cutter, unless you are happy with the depth mic readings at 4 points in each bore

I like the shim stuck to the liner on install less chance of it getting dragged into the bore on install seen that happen as well! bead of scone on ledge and liner as Joey mentoined! again I been away from this for a bit but some things do stick around in my knogin !🙄

[Joey Mack]

Without a shim, the bead goes on the shelf. You need to shoot straight when inserting the liner so you dont smudge the bead of RTV with the end of the liner. 

Yes to putting the shim on the liner . Zero chance of pinching it.

[fjh]

Great Minds Joey! 

[Joey Mack]

Yep...