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Daniel Wilson
Daniel Wilson,
Category: Medium and Heavy Trucks
Satisfied Customers: 4373
Experience:  Owner at DJ Wilson
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PLEASE READ MY POST THOROUGHLY BEFORE RESPONDING AND ANSWER

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Hello,
PLEASE READ MY POST THOROUGHLY BEFORE RESPONDING AND ANSWER THE QUESTIONS IN YOUR FIRST REPLY!:
I am a professional technician and just finished an in-frame rebuild (all new liners, pistons/rings, bearings, gaskets, and new complete cyl head) on a 2007 Hino 268, with a J08E engine.
It runs great but is getting coolant into the oil. I drained the oil, pulled pan, pressurized the radiator and found coolant leaking past some of the liners.
When installing the new liners, they seamed to go in really easy, sliding into the hole with only hand pressure.
VIN# *****: 5PVNJ8JT972S51043
engine # 6HMXH07.7JTA, model #JO8E-TA
mileage: 524000
once again ... PLEASE READ MY POST THOROUGHLY and ANSWER THESE QUESTIONS IN YOUR FIRST REPLY!:
1. These are "dry" liners as far as I know, how would they leak coolant?
2. how do the liners seal in the block?
3. Are there any coolant passages from the block into the area between the liner and the block?
4. Should the liners need to be pressed in? Is the fact they slipped into the bore with only hand pressure a problem?
I don't recall seeing anything in service manual about pressing or sealing the liners.

Hi Robert. My name is***** will be glad to help you with this but impossible the way the site is set up for us to get this all in one reply since we have a 5 minute timer to send an initial response. So bare with me while I pull up your engine specs and information to give you accurate and complete information to help you out here.

1. The flange seals against the counterbore when the head is torqued. Therefor the liner protrusion has to be correct an in specs for all liners or flange failure and leaks will occur. Also the counterbores need to be cut and shimmed to obtain the correct protrusion and correct any imperfections in the block and checked for cracks. the liners marked for the correct protrusion an best clock position to get closest to specs on the protrusion.

2. answered in #1. closely machined tolerances, correct liner protrusion, and head torque.

3. No coolant in this area means a counterbore or flange problem most likely or potential cracked block. Most likely liner flanges not sealing due to bad counterbores and incorrect liner protrusion.

4. They are a slip fit on this engine.

Also verify the block deck is true and within specs before counterboring and shimming to bring protrusion into specs. Some machine shops will come out to your site to do the counterbores and provide you the shims. Be sure to install the liners in the best clock position " marked" by the machinist so the results are exactly what was machined per cylinder.

Daniel Wilson and other Medium and Heavy Trucks Specialists are ready to help you
Customer: replied 1 month ago.
good morning Daniel,Sorry for taking so long to get back to you, my account was still setup as a professionals account and although I could read your response I could not reply back until the admins corrected it.Thanks for reading my post thoroughly and getting back to me quickly!I will be pulling the head in a couple days to inspect the liner protrusion and block.Question:1. The process for machining the block and using shims to set the liner height "should" only affect the compression sealing between the top edge of the liner to the calendar head combustion chamber correct?2. Could it also affect the head gasket sealing for coolant passages between the block and head?Since the liners are dry liners and do not seal any coolant passages, then the only way for coolant to leak past the liner would be as you said, a cracked block, or possibly an irregular deck surface (that prevents head gasket sealing the coolant passages) correct?3. If the liner is to high could it prevent the head gasket from sealing the coolant passages and allow coolant to leak past the head gasket at one or more coolant passages between the block and head and find it's way over to the liner?The coolant is definitely leak from in between the liner and block into the oil pan ... cracked block or something preventing the head gasket from sealing coolant passages .. sound right?I will let you know what I find when I tear it down. I may need additional info once I get it torn down so I'm leaving the post open>Thank you!
Customer: replied 19 days ago.
Sorry for the long delay, it took some time to get it apart and back together.I could not find anything obvious, other than possibly a very slight low spot in between the cyls on the block deck. reassembled with a new head gasket, and new head bolts, rand for a few hours checked coolant level - holding, check oil, no coolant found. Came back next day and pulled the drain plug for a small oil sample - no coolant, ran it again, and gave back to customer.Went back to do another check after the customer had it about a week; coolant level holding and no coolant in oil.Don't really know what happened, thanks for the help!