Blown Head Gasket....LX450 Refresh

[Darne]

When I rebuilt my engine in 2016 Murph recommended Kelly's Machine Shop on Hatcher Rd.
Hope this helps.
Dan

 

[mudgudgeon]

Thanks 60, I guess I didn't think about the incompressibility factor of the coolant inside the head, or the fact is was helping to possibly seal. See that's why I ask these questions.

Now i've gone down a rabbit hole of buying parts because it would be nice to get her shiny and new as much as possible. Replacing the thermostat, fuel filter, power steering pump, PHH with PP clamps, and timing chain kit with all new parts. Any reason to replace water pump? I've read they're robust, but why take a chance with a new one if the one I've had has been rock solid? I've recently replaced the oil pump seal, and fwd crank shaft seal. I've read a bunch of the HG threads on here, but maybe missed something. I'll take another crack at the search fu, but if you think of something I missed, sendUnruly!

Injector harness clips. They are a few bucks each from Ballenger motorsports, just the clips, or with pins, or with pigtails, and chances are, yours won't all survive being R&R'd
Inspect all the other harness connectors. Most will be brittle.Some are easily available from ballengers, or Toyota, some are harder to track down.

 

[Fj80oregon]

I'd sleep well attributing this to the coolant that's sitting in the cylinder. First, because that's going to seal real nice around your compression ring (think wet vs dry compression tests). Second, the space it occupies means less compressible volume in the cylinder. And on top of that, as @mudgudgeon was saying, if you did the test cold there's a good chance you're not even loosing pressure to the leak site.

The blocks on these are pretty resilient. Have your machine shop magniflux the head before they do work on it and you should be good. If you can't find a good local shop I can recommend one in northern Utah if you need.

You would have the machine shop do a dye penetrating test not magnaflux, mag flex is for cast iron or steel.

 

[60 toy ota]

You would have the machine shop do a dye penetrating test not magnaflux, mag flex is for cast iron or steel.

Yeah sorry for stinkin up the place with my brain fart

 

[lumbee1]

did you have any clearance issues getting the head over the ARP studs
?? looks pretty tight by the firewall

Nope. No issues at all.
Let me clarify, the studs where installed after the head was installed. The head is heavy and installing the studs first would have been a big mistake.

 

[KINGCM]

So head was removed with engine in and hood removed. Currently at the shop getting pressure tested/decked/ and valve job done. All in all very tedious but doable even with my limited skill. A couple of things. Lower intake plenum bolts were a little biatch getting to, but overall it went well. Broke the rear knock sensor like an idiot but a new one is on order. Im a little worried about fishing the freaking harness back through over the transmission on reinstallation.

Planned on buying an injector pulse cleaner from amazon. Not sure if that is worth it in terms of cleaning them out but figured at $40 bucks it couldnt hurt.

Current goodies not installed quite yet:
-radiator hoses
-water pump and thermostat
-spark plugs
-power steering pump and resevoir
(should i paint the resevoir before installing or keep the new chrome finish? Old one is black)
-All new gaskets and orings
-phh heater hose kit and constant tension clamps

Im sure im missing something. I think i spent around $1800 on parts alone.

Thanks Mudgudgeon for the injector clip suggestion. Mine all survived but i can see the deterioration.

As far as the blown head gasket, i dont look at these all the time so Im not really sure, but I wouldve thought that it would be readily obvious where the location was on the gasket. Its obvious that coolant got to the cylinder as you can see it was steam cleaned, but there doesnt seem to be a smoking gun as far as the gasket integrity. Maybe you experts can enlighten me. Thanks for all the help.

 

[efjayatee]

@KINGCM
Upgrade the fan clutch to higher viscosity oil of ur choice. The 15k viscosity is the Popular mod. Might aswell rewrap the harness with high temp heat wrap.
Lastly, replaced the intake manifold hardware. I had 2 "loose" and one stripped w/out realizing if weren't for the HG rebuild.

 

[KINGCM]

@KINGCM
Upgrade the fan clutch to higher viscosity oil of ur choice. The 15k viscosity is the Popular mod. Might aswell rewrap the harness with high temp heat wrap.
Lastly, replaced the intake manifold hardware. I had 2 "loose" and one stripped w/out realizing if weren't for the HG rebuild.

Fan clutch ironically was replaced with 15k fluid about a week before the head gasket went. Hardware for intake…copy!

 

[KINGCM]

Another question I have, is the coolant channels on the block to include the entire coolant system has rust colored deposits every where. Is that the normal for a vehicle with 240k or was this because some previous owner used normal hose water for some period of time?

 

[lumbee1]

From the oil caked on the pistons, be sure to replace your intake and exhaust valve guides with Toyota OEM. The valve guides get hard over the years and allow oil into the combustion chamber. Causes smoking, oil loss, and the crusty buildup.

 

[alia176]

Good idea on purchasing an injector pulse cleaner as it'll pay for itself after one round!

Good job on tackling this job, not an easy job but worth the effort. I usually suggest people to pull the whole engine with the ECU harness laying on top. There are other things that'll need to be addressed like the upper oil pan arch seal, front/rear main seals, and the list goes on!

Again, nice job amigo.

 

[KINGCM]

From the oil caked on the pistons, be sure to replace your intake and exhaust valve guides with Toyota OEM. The valve guides get hard over the years and allow oil into the combustion chamber. Causes smoking, oil loss, and the crusty buildup.

Yep, guides are with the machinist shop and should be near completion for the decking/valve job. Quick question and maybe a dumb one, are there any concerns with rotating the engine though each of the cylinders tdc's to clean the top of the piston. Obviously getting back to one tdc for the head reinstall, but is the juice worth the squeeze to clean the top of the pistons?

 

[MissahPapaJ]

Pretty clean...no scarring. Bottom end is "like new". Replaced what i can while its out for resurfacing.
New:
Valve stems
Valve job
ARP studs
Throttle body cleaning
Idler pulley
Pulley bearings
EGR cleaning
Thermostat
Spark pugs
Fuel Injectors set
Knock sensors
Ignition wire set
Exhaust studs
Vacuum switch Valve
Fuel filter
PHH hoses
Rewrapped engine harness

When you use ARP studs do you need to follow a alternate torque specs?

 

[efjayatee]

When you use ARP studs do you need to follow a alternate torque specs?

80 ft-lb

 

[MissahPapaJ]

80 ft-lb

Single pass same sequence?

 

[efjayatee]

Single pass same sequence?

Standard multi-step crossing pattern (30 ft-lb 55 ft-lb 80 ft-lb)

 

[KINGCM]

Ok so head came back from the machine shop. I was told that it was pressure checked and was good, and deck was machined but they said that it was only warped .006 which I believe isn't too bad. Next questions, is how clean do I need the block to be? I have gently scrubbed with greenie scotch bright pad and brake cleaner, to include taking some gentle passes with a razor blade to see if I had any high spots but still isn't all that clean and has old gasket residue. Should I continue to clean using soft brass or less level cleaning or is this sufficient for an OEM gasket?

 

[KINGCM]

After spending some more time with slightly stronger cleanig materials, I was able to get most of the residue off. After doing so, I noticed that it looks like the gasket has chemically etched the top of the block. Is this normal? And should I clean it any further or keep it as is?

 

[Nframe]

Etching is normal. You are good to go.

 

[KINGCM]

Etching is normal. You are good to go.

Thanks Nframe.