Working on 3rd Head Gasket install.... (1 Viewer)

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Got started on the 93 today and it's stripped down to just the valve covers and head for tomorrow morning. Boy that HG DVD comes in handy (shameless plug).

Have two interesting items to report. First, one of the intake manifold studs that holds the halves together was installed too deep at the factory. As a result, the guy who subsequently installed the nuts on the studs stripped the stud/nut as it ran out of threads at 2. I'll replace it.

Second, I broke the entire cast iron EGR valve body in half. Was half listening to my brother in law and using a persuader pipe on that big union nut. Lesson learned - pay attention to what you're doing!

Other than that it is coming along fine. Using PB Blaster on the exhaust manifold bolts for two days helps incredibly. Should have gotten some on the EGR union, too.

So far all the use of synthetics since new, mid/premium fuel, Toyota filters, replacing the PCV valve and basically over the top maintenance seems to have mattered not. The intake and throttle body are filthy just like the used 97 was and the distributor came out with identical oil deposits on it as well. I'm interested in seeing the inside of the valve cover tomorrow, as well as the valve/cylinder environment. So far it honestly looks like all that horsing around is worthless. I'm too anal to change, but wanted to call it like it is for you guys - I would never have expected this.

Also, one of my head sensors has clearly been puking coolant for a very very long time. It must have been coming out SO slowly that it simply evaporated in a ring and never dripped. So, I never saw it as it's hidden up there quite well. There's a frothy, rubbery bright pink ring around it that looks very wierd and actually feels rubbery. The evaporated essence of Toyota Red.

DougM
 
Thanks for all your work there Doug. Interesting to hear that all your meticulous work didn't seem to help that much, but I'm with you I would keep doing it anyway.

Good luck.
 
IdahoDoug said:
So far all the use of synthetics since new, mid/premium fuel, Toyota filters, replacing the PCV valve and basically over the top maintenance seems to have mattered not.

DougM


Although I doubt you not this is a depressing statement.
 
You know, being on the outside looking in, it would almost make me believe that over-maintaining your rig leads to HG failure. It certainly hasn't helped you avoid it. Not trying to bust on you, just an observation from far away. You've got some bad luck with those HG, good thing you're competent enough to be able to do it yourself. :cheers:
 
So, we should drive it like we stole it?
 
I always get a wierd feeling about spraying things like brake cleaner to clean the block, or throttle body cleaner etc. All these penetrating solvents eat up everything. But from Dougs posts it sounds like mainly that cylinger #6 is to blame.
Doug, I thought I was going to rip that entire EGR pipe off when I took mine apart. That pipe union bolt has to be one of the hardest to get to and hardests to break loose bolts on the truck. Also thought I was going to rip into the wiring harness. That would be my luck. I gave up and hit it with WD40 waited over night and it was still tough be it let loose.
I give it one notch harder than the starter.
 
Good luck, hopefully no more suprises for ya. Just watched the whole dvd 2 nights ago, will definitely help if/when I have to the HG. Did you notice you had like 5 frames of a Vehicross climbing something in the middle of the DVD :doh: :D
 
man, you must be getting good at this...
I hope you're taking more photos and movies to show differences in conditions and refining the procedures... :)
 
That does suprise me that using high-test gas along with cleaners and anal maintanance hasn't lead to a cleaner motor.
 
Well Doug you made my day. By my own description I'm a minimalist when it comes to maintenace. Do only what's needed to make the vehicle run properly and avoid predictable failures. Glad to see I've saved my self some cash and have done no harm.
 
Doug

What was your average oil change interval on the '93?
 
have you pulled the valve cover yet? if it is no cleaner there then..........
 
Yeah I don't think any kind of maintenace will keep the throttle body or intake clean. The best way to keep it clean would be to get rid of the EGR system. When you dump exhaust gas into the intake it just isn't gonna be pretty.

I'm interested to hear how it looks under the valve cover as well.
 
alia176 said:
So, we should drive it like we stole it?

I have found that the majority of my vehicles run better when you don't baby them. I'm not saying abuse them, but run them like they were intended. I was always told to give 'em the old "Italian tune up", meaning don't be afraid to rev it. Seems to work for me.
 
AKA "Warp-tune"...:D


Sometimes "Rod bearing test"...:D
 
ive been following your hg problems doug-what a bummer-great to see you have kept your head up and are realy offering a service with that hg dvd.
concerning this statement: "The intake and throttle body are filthy just like the used 97 was and the distributor came out with identical oil deposits on it as well."
could you be more specific? what do you see? pics?
 
Wow lotsa wonderful observations throughout this thread! I absolutely agree that the use of synthetics, premium fuel, etc. will not work much at cleaning the intake system. As darwood stated, you just cannot purposely put all the byproducts of combustion (and lack of combustion) back into the intake and still have a completely clean intake system, at least without separate maintenance specifically for the intake system.

I think that thorough throttle body cleanings are essential and I think that these cleanings should be done both on and off the truck. Off the truck is the typical throttle body remove, clean, replace. For on the truck, before every other oil change I take a can of BG Air Intake System Cleaner, Part # 406, remove the intake tubes from the TB, open the throttle blade WOT, spray about ten seconds of spray into the TB past the throttle blade in all directions, close the throttle blade, quickly connect intake hoses and start the engine with about 1/2 WOT on accelerator pedal. Run the truck for several seconds this way, repeat the procedure three to four times, then drive the thing ten miles or so to get all the excess of that out of the system. You would be amazed at how clean the intake system gets from this process and the throttle response is so much sweeter as well.

On the "Italian Tune Up", yes i absolutely agree you gotta get all the moisture and muck out of your intake and exhaust systems, clean the carbon, etc. As locrwln1 stated dont be afraid to rev it, I always romp on revs with whatever I own and with whatever I own after a weeks worth of commuting they feel so sluggish compared to after a really revving ride. I'm convinced our emmissions equipment contributes to this problem. So the message is "massage the motor" in all ways, good maintenance, as well as good usage. HTH. :cheers: :cheers:
 
Well, the head is at the same shop that did the 97 and I asked them to also mill .010 off based on how well that worked out. As to the cylinder deposits, valve cover, etc - no discernible difference between the 93 and this one. I mentioned the distributor coming out dirty as a harbinger since when you pull it off there's a long part that lives in the valve cover. The interior of the valve cover was not grundgy like I've seen on other vehicles, but neither was it notably cleaner than the 97 so I'm calling it no difference. In fairness the 97 had been run about 6000 miles with Mobil 1 and may have been cleaned a bit by that. But on the 93 you can clearly see oil deposits from years of the spinning timing chain, etc. With 100% synthetic use I frankly expected to see nothing but bare metal and that is emphatically not the case.

The cylinder environment was absolutely filthy. Black crackly crud on the pistons, valves lightly carboned, combustion chamber lightly carboned exactly like the 97 was. I'm truly surprised that good fuel, regular techron, etc did zip. OCD - 0, normal types - 1.

#6 was clearly getting cleaned by coolant but I truly got lucky there and so little time elapsed from detection to teardown that there was still loose carbon and crud laying about. #6's piston top was about 70% cleaned I'd guess.

The gasket was very well attached to the block - less so to the head. I really had to pull to get it off the block vs the 97's almost lifting off. I removed it from front #1 to rear #6 in order to avoid prying on the suspect area to preserve it, and the rear half of #6 came off notably more easily. This indicated to me it had lost sealing back there. I will be closely inspecting it Sunday - couldn't today as I ended up hustling around all day after dropping the head off. It was in better shape than the 97's was at first glance, however. I have the 97's on hand and will be posting photos of both.

I put the broken part of the EGR valve in the bench vice and used a pipe wrench with a 3 foot pipe length to break it loose. Mine was really on there for some reason. For those of you taking yours off for a HG or other maintenance, be sure to give it a good soaking. With the hood off like I suggest for the HG, it's a simple matter to put a length of pipe over your wrench when attacking this for great leverage. Obviously I generated enough leverage.....

As for oil interval, a couple years ago I recall posting that my average oil change since new was about 6200 miles from my log. Each and every one with Mobil 1 and Toyota filter.

My wife and kids are still in FL and they have the digital camera, or I'd post pics. Maybe I can borrow one this weekend as it will be buttoned up before they come home next week with said camera.

DougM
 
IdahoDoug said:
With 100% synthetic use I frankly expected to see nothing but bare metal and that is emphatically not the case.

As for oil interval, a couple years ago I recall posting that my average oil change since new was about 6200 miles from my log. Each and every one with Mobil 1 and Toyota filter.

DougM


Interesting. Anecdotal, I know...but the PO of my '97 stated he changed his Mobil 1 every 5,000 miles (no reason not to believe him) and I had a fair amount of varnish and even a little sludge in my motor, under the valve cover.

I did a double AutoRx right after I picked it up, and am in the rinse phase of another (30,000 miles later) right now. I have been using mostly Valvoline Max-Life day in and day out, and between the AutoRx and the esters in the Max-Life, it is finally getting clean.

Not scientific I know. And there are some motors that seem to stay clean with 5 - 7,000 mile OCI on Mobil 1 or other good synthetic. I'm not too sure about the 1FZ...not sure how much it matters, either
 
Doug,
Have you magnafluxed the head?
 

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