Lost compression on cylinder 5

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OpossumWrangler said:
On the power steering note, I do have a leak in that area. I think it may be from the reservoir, that’s a common problem right?
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It is, but I'd say the high pressure line is even more so.
You'll want to replace the tranny lines too if they're original. Once they've been softened by time and oil leaks the stress of R&R can break the fibers inside without looking worse for the wear externally, that is until they rupture under load.
 
The reservoir leaks on mine a little. I have a new one to put in but haven't yet. All other hoses were changed. So yeah I think it is a thing.
 
I got quoted $750 to $1000 plus parts today. By the eye my valves look alright and bucket clearances were in spec. Not sure if that one warped or if I’ll need new seats. Either way I would expect that price to go up. I may drop in a couple more machine shops this week because those guys had a 3 month lead time.
 
I feel like I have to apologize for how long this is taking. I’m posting as I go and I do not have much free time to work on my 80. I am about to start reassembly, now that I have all of the parts and a freshly machined head. What’s currently holding me back is this wiring harness. Is it a viable option to just splice repair these bare spots and then wrap the harness?
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OpossumWrangler said:
I feel like I have to apologize for how long this is taking. I’m posting as I go and I do not have much free time to work on my 80. I am about to start reassembly, now that I have all of the parts and a freshly machined head. What’s currently holding me back is this wiring harness. Is it a viable option to just splice repair these bare spots and then wrap the harness?View attachment 4166018
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Open it up and see how cooled it is before you buy a new one. Sometimes it’s just a couple of wires. Wrap it back up with good heat shield tape. Mine has been fine for 7 years after rebuild.
 
Hard to tell how bad the damage is without cleaning it up more, but mine looked like that by the EGR a few years ago. Cleaned up, spliced, wrapped it up, heat tape, fastened away from EGR pipe. No issues for many hard miles since.
 
Conclusion​
Okay, I have pretty much finished this project and It's about time I finish this thread up. I left y'all at reassembly last so I'll try to start off there. I started cleaning the head with a scotch brite pad and then decided that i didn't like the way those start to deteriorate and leave debris. I switched to a carbide scraper in a careful fashion, and then i was put onto these things by an engine builder that i work with (he actually suggested the 3M version but I don't have that $$). Anyway all of these methods got the head to an acceptable level of cleanliness by my standards. I repaired the wiring harness and tapped it up. Extracting the screws in the oil pump cover was a nightmare, i had to heat them up and tap on the ratchet driver while torquing them on every one. I ended up only stripping one of them. I found where a previous mechanic had twisted the head off one screw (no clue how they managed that without stripping the screw head), so i had to extract that with a punch and hammer.

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I bought a OSK timing chain kit and got that done while the motor was torn this far down. After that I bolted up the cover and had a buddy help me get the oil pans mated back to the motor. This is difficult in frame, and could not have done it without an extra set of hands.

Next i cut some block off plates from a piece of 3/16" x 2" aluminum flat bar for an egr delete, and I also added a resistor for the egr sensor. There was a gross amount of build up inside the manifold. The truck was burning a quart a week of 15w-40 and the egr gave it the privilege of burning it twice. No more of that though.
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I took a cutting disk to the old head bolts and chased the bolt threads, then had a buddy help me set the head. These are the ARP studs I went with. I used all toyota gaskets on this project. Only non-toyota parts used were the studs, timing chain kit, and heater/coolant hoses.
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Continued...
 
Next I replaced all of the power steering hoses and resealed the vane-pump with the toyota reseal kit. The kit did not come with a bearing, but the one in there seemed to be in really good shape so I didn't bother replacing it.
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Next I got the rest of the accessories bolted up and started putting the front end back together. That is about all of the pictures i've taken, but before i wrap this up ill hit on a mistake i made while putting the distributer on. I somehow got the distributor on retarded by one gear tooth. This sent all of the combustion into the exaust header on the first start up. While i was trying to figure out why it would barely run, the exhaust amnifold started glowing orange and it didn't take very long to do so. I shut it down soon as this was noticed and figure out why the ignition timing was off. I managed to get the distibutor gear set right without taking the valve cover off, then set the timing according to the FSM with a friends timing light. I've been daily driving the rig for a little while now and the only problem ive had is that it seems like an injector is intermittingly sticking open. I put a set of bosch injectors on it, so this is disappointing. I put a set of bosch injectors on an XJ i had several years ago and had the same problem right out of the box. Here shortly ill take the intake off and put my factory injectors back on to be sure. Other than this, she runs great and has quite a bit more power than before and isn't consuming oil.
 
OpossumWrangler said:
Next I replaced all of the power steering hoses and resealed the vane-pump with the toyota reseal kit. The kit did not come with a bearing, but the one in there seemed to be in really good shape so I didn't bother replacing it.
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Next I got the rest of the accessories bolted up and started putting the front end back together. That is about all of the pictures i've taken, but before i wrap this up ill hit on a mistake i made while putting the distributer on. I somehow got the distributor on retarded by one gear tooth. This sent all of the combustion into the exaust header on the first start up. While i was trying to figure out why it would barely run, the exhaust amnifold started glowing orange and it didn't take very long to do so. I shut it down soon as this was noticed and figure out why the ignition timing was off. I managed to get the distibutor gear set right without taking the valve cover off, then set the timing according to the FSM with a friends timing light. I've been daily driving the rig for a little while now and the only problem ive had is that it seems like an injector is intermittingly sticking open. I put a set of bosch injectors on it, so this is disappointing. I put a set of bosch injectors on an XJ i had several years ago and had the same problem right out of the box. Here shortly ill take the intake off and put my factory injectors back on to be sure. Other than this, she runs great and has quite a bit more power than before and isn't consuming oil.
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Maybe send the injectors out for cleaning and flow testing first then slap them in. In my experience aftermarket injectors are usually never the answer.
 
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