Coolant leak inbetween head and block.

[mikkhh]

(04-06-2026 )mechanixrds Wrote:  I am 100% a believer in aftermarket parts being complete trash now. The pictures of the block I posted were after the machine shop decked it. We don't use power tools on the deck when cleaning the residual head gasket material. The protrusion measurements are quality issues with aftermarket parts, in my opinion. If anything, others should learn from my mistake and see why aftermarket parts are garbage. The proof is in the pudding.

I did measure the dowel pins, as Nostalgic mentioned, and dowel pin bores in the cylinder head and measured .0472" on both.

Besides aftermarket parts and replacing the block, are there any other suggestions or recommendations you may have?

On genuine set you get away with measuring one liner and cutting other to spec from that. But aftermarket set of six liners can vary 0.05" . Only way to fit those is to fit specific liner to specific cylinder. Some aftermarket liners have not lasted even more than 500 hours on 20 year old no dpf (just egr) commonrail excavator liners - they develop cracks on exhaust side, no visible major piston scraping evident. Material is just way weaker.

Prices for genuine parts liner wise in Europe for example scania 13l truck engines is 700 euros per liner. Scania is similar mid stop design as ISX . HPI and XPI are both co developed. Newer 2017+ 13l 500hp completely stock (no EGR from factory like International S13) nothing deman or anything engines fail a lot even at 300 000 - 400 000 miles. Almost all have automatic transmissions and gearing wise are 950rpm at 55mph speed (trucks are limited to 56mph in Europe, some places even 50mph). Latest failed 13l that I know threw a rod through side of block at 400 000 miles. V8 engines like to snap crankshafts and are notorious for block cracks. I do not know any dealership or repairs shop in Europe that does set liner height and raises height. There are some who machine top of liner seat to "fix" corrosion and install oversized top circle liners.


Back to this topic. In first post there is picture from pistons and there seems to be carbon deposits in the center - is there leaking injector(s)?

[mechanixrds]

(04-06-2026 )mikkhh Wrote:  

(04-06-2026 )mechanixrds Wrote:  I am 100% a believer in aftermarket parts being complete trash now. The pictures of the block I posted were after the machine shop decked it. We don't use power tools on the deck when cleaning the residual head gasket material. The protrusion measurements are quality issues with aftermarket parts, in my opinion. If anything, others should learn from my mistake and see why aftermarket parts are garbage. The proof is in the pudding.

I did measure the dowel pins, as Nostalgic mentioned, and dowel pin bores in the cylinder head and measured .0472" on both.

Besides aftermarket parts and replacing the block, are there any other suggestions or recommendations you may have?

On genuine set you get away with measuring one liner and cutting other to spec from that. But aftermarket set of six liners can vary 0.05" . Only way to fit those is to fit specific liner to specific cylinder. Some aftermarket liners have not lasted even more than 500 hours on 20 year old no dpf (just egr) commonrail excavator liners - they develop cracks on exhaust side, no visible major piston scraping evident. Material is just way weaker.

Prices for genuine parts liner wise in Europe for example scania 13l truck engines is 700 euros per liner. Scania is similar mid stop design as ISX . HPI and XPI are both co developed. Newer 2017+ 13l 500hp completely stock (no EGR from factory like International S13) nothing deman or anything engines fail a lot even at 300 000 - 400 000 miles. I know one that threw a rod through side of block at 400 000 miles. V8 engines like to snap crankshafts and are notorious for block cracks. I do not know any dealership or repairs shop in Europe that does set liner height and raises height. There are some who machine top of liner seat to "fix" corrosion and install oversized top circle liners.


Back to this topic. In first post there is picture from pistons and there seems to be carbon deposits in the center - is there leaking injector(s)?

There could be. The original failure it came in for was for a cracked head and coolant inside of Cylinder #1. It was a garbage aftermarket head... I haven't ran it since I tore it apart to replace the head under warranty as now, I have a different issue, an external coolant leak coming in between the head and the block on the front right corner of the engine. I've gone through two head gaskets at this point.

[mechanixrds]

(04-06-2026 )Rawze Wrote:  

(04-06-2026 )mechanixrds Wrote:  ...
Besides aftermarket parts and replacing the block, are there any other suggestions or recommendations you may have?

This is the way an ISX should be inframed. Anything less, and it will not be a million mile build.
info: https://rawze.com/forums/showthread.php?...6#pid70606

I appreciate your input. From now on, I will be following those procedures. And if the customer thinks it too expensive, he can go to the "cheaper guys" and find out for himself what happens. I turned down a rebuild on a Cummins a couple weeks ago when I found out they bought their own parts from on an online store.

[Nostalgic]

Can you mark the picture of the block deck you posted where the coolant is leaking externally?

Other than mentioned items, is it possible the head bolt was tightened down with oil in the hole and cracked the block?

[mechanixrds]

(04-06-2026 )Nostalgic Wrote:  Can you mark the picture of the block deck you posted where the coolant is leaking externally?

Other than mentioned items, is it possible the head bolt was tightened down with oil in the hole and cracked the block?

After I clean the deck surface today, I will take some more pictures and upload them.

I've uploaded the video to YouTube. Hopefully this link works and you can see where it's leaking just under the thermostat housing.

https://youtube.com/shorts/T_r9slUkeeU?feature=share

Both times that it leaked, there was no oil in the head bolt holes on the block. I always make sure to cleaned them out. After the first leak, the block was sent to the machine shop to have it checked for any cracks, and no cracks were found.

Today I will be putting the head back on with an OE gasket and trying that out. I will report back with what happens.