1993 volvo l150........again

Since we fixed the planetary the engine decided it was its turn. A little back story on this machine. I purchased it from a dealer in minnesota. I had a volvo dealer do a pre buy inspection, upon which they found leaking head gaskets. The dealer agreed to replace all the headgaskets as well as the oring seals with them. Ive had the machine for two season and havent had any coolant leaks. Last week i started the machine, let it idle for 20 minutes to warm it up and then noticed the coolant leaking between the cylinders 5 and 6 heads. My retired, yet bored, diesel mechanic attempted to retorque the head to no avail. We pulled the 5th and 6th heads and found both sleeves had crosshatching around the top 1/2 inch of the inner surface. To me it looks factory, but he feels that someone tried to expand the sleeves in the bores to try to tighten a loose sleeve issue. He also thinks the coolant is bypassing the oring seal at the top of the sleeve and is leaking out between the heads.

In short, im looking for what the correct option is for repair. Do they make oversized sleeves for this condition? Is it better to purchase a remanufactured engine and install? Let me hear your thoughts!

Brian

Look at your fire ring of the head gasket. Any dark spots, burn spots or nice shiny on both sides? Have you measured liner height against specs. It's not uncommon to have seepage occur , usually a head gasket will square things up, if there are no underlying problems.

I will get pictures of the headgaskets tomorrow. What concerns me is that these were all replaced less than 300 hrs ago and are leaking again. What is the procedure for checking liner height?

Be sure to check the flatness of the head and block. Before pulling it apart, I would have checked for combustion gasses in the coolant. If present, I would be worried about the liners sinking. If it's just leaking coolant externally, I'd be more suspicious of the gasket surfaces.

You clamp the liners down. Most guys dont have the fancy clamping fixtures so I usually use a large T bar like an OTC 17 ton push puller. Using head bolts and spacers. Firmly clamp the liner down. This is a bit of a dance between too much and too little. You dont wanna deform the liner. Then you set up your dial indicator on the outer edge of the liner where the fire ring actually sits. Make sure everything is locked down then rotate assembly so that indicator tip comes off fire ring and rest on deck . Subtract A from B and you have liner height. You'll have to ask for specs as I no longer have Prosis. Maybe reach out to your local dealer.

They (whoever that is) make a special indicator sled for the purpose. I just use a surface gauge, which is a fancy tool machinist have

I'm trying to keep it simple. Not everyone has a sled-gauge. Thought about mentioning it but didn't want to send him chasing a tool with only one use.
I hear ya, though. Mine is special Cummins tool forgot part number looks like this.
https://www.tooldiscounter.com/Item...4WeSzhqa9I1bxWc0YvYyJUBGHtEjfPxRoCobEQAvD_BwE

Thanks for the feedback. Ive taken some pics of the gaskets and block area. The leak was coming from between 5 and 6, im suspicious of the freeze plug on 6. My mechanic thought the knurling around the top half inch of the liner was an attempt to tighten the liner. Looks factory to me, but its the first volvo liner ive seen.

More photos

It's hard for me to see the head gasket pics. The last appears to have a dark spot. The one image where its straight on to the piston/ liner, the liner looks shiny all the way around as I would expect. The cross-hatch you see is factory. What I do see is coolant migration out of that one bolt hole in the deck. That makes me question if there was sealant on those threads or were they dry? I try to use international compound #2 on head bolts when they pass into a coolant passage. If you fill your cooling system back up slowly, you should be able to tell which holes share paths.
I can't remember if that plug is oil or coolant. Sure wouldn't hurt to reseal while you have it off.

Is that plug pressed or threaded? You may be onto something with the head bolt threads and sealant. The leak got worse when we loosened and re torqued the head bolts.

Although Phil has been absent from HEF for a long time he can still help.
This is how he measured liner height.
I think he borrowed that micrometer because I have one like it and he wanted to buy it.
Unfortunately he disappeared from the internet before he could get the cash to me.

Yesterday we clamped the liners and verified that we have .007 protrusion. Spec is .004 to .008. We then plugged the coolant ports in the block and filled the cooling system. Again, no leaks. The heads have been sent out for pressure testing. Im starting to think we have leaking freeze plugs between the heads..

A little follow up. Neither head had any leakage when they were pressured up to 30 psi by the machine shop. I purchased two head gasket kits and new head bolts from volvo. today we reinstalled the heads with all new head gaskets, seals and head bolts and torqued everything down. We filled the cooling system and checked for leaks prior to re installing the exhaust manifolds and intake. After installing the manifolds we started the machine and pulled it outside. After two minutes we had leakage at the exact same spot. Inbetween heads 5 and 6. You could actually see the coolant bubbling from under the head gasket and eventually ran out the side and down the block. My diesel mechanic thinks there could be a counter bore crack which is causing a leak when the head is torqued. How common are liner and counter bore issues in these engines?

They are not common , did you measure protrusion at 4-6 places around each hole? Did you apply compound #2 to the threads? Did you reseal the large Alan plugs ?

Yes protrusion was measured in 4 places. We oiled the threads per the service manual and verified that the holes are blank. They do not go through a water jacket. All 4 allen plugs were resealed as well.

Bolt holes blown out ? Too much oil on threads creating hydraulic condition .

Yes, we blew out all of the head bolt holes. With the wear that was in the liners im contemplating installing a remanned long block. Best price ive gotten is 17k. Which is half of what volvo quoted.

I am suspecting the plug.