Enders swap, Update 11/29/19 Options

[enderswift]

I'm ready

This post has been edited by enderswift: Nov 29, 2019 - 6:58 PM

[enderswift]

Hey everyone,

long time no update, but I've been busy with work and school so there's been little time to focus on the rebuild. Luckily the semester is out for winter break and I've had the chance to get some stuff done. As I've mentioned before I am focusing on the cylinder head until it is completely done before moving on to the bottom end. So with that in mind I've been busy cleaning, measuring, and ordering parts:


A quick before picture:


My first round of cleaning involved scrubbing the cylinder head with a tooth brush and simple green extreme before rinsing with a pressure washer


The real stubborn stuff required a brass brush and more simple green (brass doesn't scratch aluminum but is much more effective than tooth brush bristles).
This was an extremely tedious process but I'm really happy with the results.


I obviously couldn't reach everything with brushes and a power washer, so I went to Grainger supply and picked up 3 gallons of Simple green Boeing Cleaner and soaked the head. I was AMAZED at how awesome that stuff is. The hidden crud in the oil channels exploded off the head right before my eyes. In retrospect I probably could have just soaked the head from the beginning and avoided all that scrubbing. But oh well

http://industrial.simplegreen.com/ind_products_extreme.php





I also took the time to clean and spray the valve cover in VHT wrinkle paint. Painting with this stuff is no easy task since the slightest change in temperature will cause it to wrinkle in patches. I took a lot of time cleaning, sanding, and painting to avoid that problem. I think it came out pretty well.


Next step was to start measuring in preparation for machining.


Measuring turned out to be much harder than I expected simply because Toyota maintains specifications in the ten-thousandths range. This meant that I had to borrow a micrometer accurate to 4 significant figures and check all of my values. It was very time consuming.

Everything was within tolerance but the exhaust valve stems were only 2 ten-thousandths away from being worn out. This concerned me so I measured the center of the valve stems (which doesn't wear) and saw that the valves were on the small end of tolerance when brand new. Confused, I measured the valve guides with a bore gauge. The difference between the bore diameter and the valve stem gives you the oil clearance spec. In my case I was comfortably in the tight end for all the valves. So even though the valve stems are small the oil clearance is good, which is ultimately the important measurement.



I also went on to measure absolutely everything the FSM called for and thankfully the cylinder head is in fantastic shape; despite the lack of oil changes. In light of this information I've decided to get the following machining done:

head resurfacing: The head is not warped, but metal head gaskets experience shearing forces due to the difference in thermal expansion rates that comes with having a cast iron block and an aluminum head. Therefore a smooth surface is required to avoid failure.

http://www.aa1car.com/library/ar996.htm

Cam shaft polishing: There are some directional scratches on the cam journals which probably occurred during cold starts. They pass the fingernail test but any little scratch can disrupt the extremely thin oil film that separates the camshaft and the head. Therefore since I cant polish the head journals, I'm going to have a shop polish the cams with Emory cloth instead. This should increase the longevity of the head without affecting the oil clearance.

3 angle valve cut I spent a TON of time checking the valve seating and the exhaust valves have a little bit of pitting in them. I could just lap the exhaust valves by hand but I figured I might as well go big and get a 3 angle done on exhaust and a refresh on the intake. Go big or go home. The downside is that I'll have to replace all of the shims or shorten the valves since cutting makes them sit deeper in the head.


Finally I found one lifter that is going to need replacing, I think something went wrong during case hardening because it looks like the carbon diffused unevenly around the sides. Fortunately the lifter bore was unaffected by this so I can get away with just replacing the lifter.... for ~$20

Currently I'm in the process of selling extra stuff from the clip and saving money to buy the master rebuild kit, and pay for machining. The Toyota dealer near me is active with the Toyota scene so they gave me discounts on a lot of my rebuild parts. Its pretty awesome, but unfortunately a bunch of stuff has been discontinued and I'm gonna have to dig around to buy stuff like the oil and coolant pumps.

anyway, here's my humble progress thus far. I wish I had some more interesting stuff to post, but I want to take my time and be thorough with this.

This post has been edited by enderswift: Jan 14, 2013 - 7:11 PM