I can't believe I'm posting another catastrophic failure thread, but...here I am. For those not in the know, I recently had an inexplicable H55f failure, remedied by a new unit built by @cruisermatt, which due to the freight company (YRC Freight)'s careless treatment, took two tries over two+ months because those rat ba——ds dropped the whole pallet off a truck and bent the input shaft of the first one, then denied any wrongdoing. Matt was great throughout the whole process and I'd highly recommend working with him.
I got to enjoy my truck for 2 weeks (and a sweet 2 weeks it was), and now it's looking like a blown head gasket—I was out, late at night replacing all my belts to try and fix a nasty squealing that appeared to be from my A/C belt (see here for a vid, sound really starts being audible at 0:26). After installation and confirmation that the squeal was gone, I noticed a puddle of coolant on the ground and figured I must have bumped or cut a hose, but couldn't find any leaks. So I started 'er up and noticed coolant absolutely SPEWING out of the oil pan gasket. My fear is that this is a blown head gasket, but this thread will document my troubleshooting/diagnosis & the eventual fix.
Ok, I'll first rewind a bit for more context. it's probably perfectly fine to skip by as it's a bit long, but I figured it was worth posting for all the possible context instead of a ton of back-and-forth. I've greyed it out so it's easy to skim past.
I replaced my belts and the tensioner pulley, an easy and uneventful job, and pulled the throttle cable by hand while in the engine bay to get the best listen and make sure that the squeal was gone. The squeal must have been from one or both, because even at higher RPMs, the sound seemed to be gone, but I'm now noticing a HUGE puff of white smoke that continues through the RPMs, coming from what looks to be either or both the valve cover gasket, and/or cylinder 1 exhaust manifold gasket. I turn the engine off and am double checking my belt tensions, when I notice a small puddle of coolant on the ground. I figured I must have bumped something during the belt install, but I check all the hoses, and can't find any wetness. Odd.
I turn the engine back on, and hop underneath the engine while it's running, and there's a stream of coolant coming from the front driver's side (RHD) corner of the oil pan. I figure I must have missed something, so I turn the engine back off and desperately search for a hose that's leaking, hoping that I just missed something on my last search, and that my worst fear isn't true—that my coolant and oil are now mixing.
My search proved unfruitful, so I gritted my teeth and started 'er up again. This time, it's more obvious that coolant is now SPEWING from the oil pan gasket. I immediately shut the truck back off, and take a couple days to try and forget about it and come at this with a clear head before I panic and spend a few thousand dollars on the wrong parts.
I need to leave to take a friend to a Dr.'s appt, posting now so I don't accidentally lose my progress. Will update shortly while waiting at the Drs.
I got to enjoy my truck for 2 weeks (and a sweet 2 weeks it was), and now it's looking like a blown head gasket—I was out, late at night replacing all my belts to try and fix a nasty squealing that appeared to be from my A/C belt (see here for a vid, sound really starts being audible at 0:26). After installation and confirmation that the squeal was gone, I noticed a puddle of coolant on the ground and figured I must have bumped or cut a hose, but couldn't find any leaks. So I started 'er up and noticed coolant absolutely SPEWING out of the oil pan gasket. My fear is that this is a blown head gasket, but this thread will document my troubleshooting/diagnosis & the eventual fix.
Ok, I'll first rewind a bit for more context. it's probably perfectly fine to skip by as it's a bit long, but I figured it was worth posting for all the possible context instead of a ton of back-and-forth. I've greyed it out so it's easy to skim past.
- After my H55 R&R, I still needed to pass emissions, but was running a bit dirty (only test I need to pass is opacity). To remedy this I:
- did valve clearances, which helped my startup/idle/running quality, but the tailpipe didn't clean up enough that I figured I'd pass.
- I checked w/ a smoke machine for vacuum leaks, and fixed one very small one at the connection to the overboost warning light. Everything else was in great shape.
- I had a boost controller (Halllman Pro) and EGT/boost combo gauge (Auber 24V combo) sitting around ready to install, so I figured I'd throw a bit of boost (NOT fuel) at it to clean up the tailpipe.
- Before doing so, I pulled the intake piping and checked the radial & axial play on my ct26. I had zero perceptible axial play, and radial play so small that I questioned whether or not I was actually feeling it. There was a small coating of soot in the intake, but nothing that seemed unreasonable after 265k km.
- Feeling good about the condition of my turbo, I installed the boost controller, figuring that I could just pass emissions and get road legal, then deal with the EGT and boost gauges when new exhaust manifold gaskets and studs (and some other parts to keep on hand) show up in a few weeks from megazip UAE and japan.
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- I set boost by starting at zero > taking a test drive > turning up a half-turn > test drive > repeat until I hit the overboost light, then turn down a full turn for safety.
- My fuel screw is still safety wired from the factory, so I know I'm not getting too much fuel.
- I drove around town for a week or so, enjoying the extra pickup but not going crazy. After all was well, I wanted to finish off the old tank of diesel that had been sitting for a couple months while the transmission was replaced and get a new tank in before going for emissions again. I also knew that a bit of stress can help clean things up, so with beautiful weather on the horizon, my girlfriend and I decided on a trip up to twin lakes, near leadville. You can get some amazing last-minute campsites there if you have a capable truck and know how to use it.
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- Our trip was totally uneventful, other than noticing a high-pitched whine around cruising speed right when the engine was unloaded. It didn't sound particularly worrying, very similar to the early stages of a belt squeal, but to be safe I wanted to check it out.
- The cruiser pulled strong, easily holding 65 up&down I-70 to/from Denver>Leadville>Denver.
- I was watching like a hawk the whole trip, and there wasn't a single sign of overheating (if anything it was running a tad cool), and as soon as I hit boost, my tailpipe was completely clean.
- I had noticed while searching for the whine/squeal that there was a small puff of smoke coming from either under the valve cover/gasket or at the exhaust manifold, so I cracked the oil filler cap, did a blowby test, and there was zero identifiable blowby, even at higher RPMs.
- This leads me to believe that, at a very minimum, my pistons and cylinders are sealing properly so hopefully I can check that off the list of possible issues.
- this puff of smoke happens right as I get on the throttle, then disappears, and comes back (another small puff) when I lift off.
- I noticed my top (a/c and alternator) belt had some cracking and was vibrating pretty bad, and the sound seemed to be coming from there, so I felt safe to continue driving the truck.
- I drove around town a bit to run some errands—There was a small amount of white smoke that I began to notice from the tailpipe, but figured it was caused by the intake/exhaust leak that I found causing the truck to run lean. This is nothing major, only a puff, so I didn't worry too much, figuring it would clean up after I install the new manifold and intake gaskets that are on their way.
I replaced my belts and the tensioner pulley, an easy and uneventful job, and pulled the throttle cable by hand while in the engine bay to get the best listen and make sure that the squeal was gone. The squeal must have been from one or both, because even at higher RPMs, the sound seemed to be gone, but I'm now noticing a HUGE puff of white smoke that continues through the RPMs, coming from what looks to be either or both the valve cover gasket, and/or cylinder 1 exhaust manifold gasket. I turn the engine off and am double checking my belt tensions, when I notice a small puddle of coolant on the ground. I figured I must have bumped something during the belt install, but I check all the hoses, and can't find any wetness. Odd.
I turn the engine back on, and hop underneath the engine while it's running, and there's a stream of coolant coming from the front driver's side (RHD) corner of the oil pan. I figure I must have missed something, so I turn the engine back off and desperately search for a hose that's leaking, hoping that I just missed something on my last search, and that my worst fear isn't true—that my coolant and oil are now mixing.
My search proved unfruitful, so I gritted my teeth and started 'er up again. This time, it's more obvious that coolant is now SPEWING from the oil pan gasket. I immediately shut the truck back off, and take a couple days to try and forget about it and come at this with a clear head before I panic and spend a few thousand dollars on the wrong parts.
I need to leave to take a friend to a Dr.'s appt, posting now so I don't accidentally lose my progress. Will update shortly while waiting at the Drs.
