Thread: Head Disassembly

I'm picking up on tearing down a motor that I started working on 15 years ago... Engine had been overheating from the prior owner, turned out to be the radiator cap! But it ended up blowing the head gasket shortly after I had gotten the car, and I started tearing it down. Then I got a deal on another engine, but didn't have the time/energy/space/money to get this done, and so things sat for many years. Spare engine is now 200 miles away and I've been unable to pick it up, so I'm back to seeing if this one can be salvaged.

So, I had already pulled the valve cover, cams, head bolts, and oiler tubes. Unfortunately, none of those parts were labeled, and I'm not even sure that I have them all. I'll deal with that later. The piston nearest the pulleys is close to being TDC, but I haven't verified the marks on the chain. I did zip tie the chain to the cam gears to keep the alignment from moving.

So, in the next day or so, I should have everything removed to let me lift the head off the block and check flatness (and this time the parts are being kept in order!). I've got a mechanics straight edge and know how to do that. My main concern is, should I take anything else apart before getting the head off? Should I remove the lifters, valve springs, or anything else? I know the lifters are oil filled and shouldn't be put on their side, and if the head comes off, then they are going to get tipped at some point quite likely.

If the head does have to be decked, should I remove everything (valves, etc) prior to sending it to the machine shop?

Lastly, spring compressor tools. I've found some threads on this topic:

http://www.sr20-forum.com/general-sr20/6109-valve-spring-removal-tools.html
How to install valve springs - SR20 Forum
http://www.sr20-forum.com/general-maintenance/40886-how-remove-cylinder-head-valves.html

But those are full of broken links to a multitude of tools. A web search finds a wide variety of tools for this job at an equally wide variety of prices. I can't even find the Snap-On one shown in that first link anymore on their web site. I'd love to hear what people are using that works well (manufacturer, model #). I'm hoping that I only need to use this tool once, but better to have the right tool just in case.

I left valves and springs in the head when I got it decked, everything else came off. You can dunk lifters in oil and bleed them before re-assembly. Not sure about a valve spring tool as I have never done it.

Good luck!
-G

If you are getting the head decked, you will need adjustable cam gears to get the cam timing set back up.

I've used the valve spring tool that looks like a big C clamp before as well as one like this: http://www.amazon.com/Valve-Spring-Compressor-Toyota-VW-AUDI/dp/B007WKGX6Q The 2nd one worked better since the head could be flat on the bench.

Pretty sure most people don't get cam gears after getting their block or head decked and are fine. In fact, I think that's not common. Slack can be taken out by the tensioner.

-G

It depends on how much is removed. The FSM has the service limits without needing gears, and the instructions with the JWT gears show how much each gear need to be moved for the amount removed. I sent my head to a machine shop to get cleaned, and they decked it without me knowing. I wasn't able to get the distributor to line up at 15deg until I installed JWT gears.

When you had this done, do you know how much was removed? I'm going from memory, but I think that the tolerance on the head is .004", and the same for the block, for a total of .008" if both need to be machined.

I have no idea how much was removed, that was around 13 years ago. I didn't have to adjust the cams much, but it was enough that the distributor was adjusted way past where 15 deg should be.

Well, the engine is finally out, what a pain in the ass that was. I didn't want to pull the tranny so I dropped it down to get it out, getting the car high enough though was a real challenge. Lucky for me the valve cover and other parts were already off to save a few inches. LOL

Tonight I should finally get the head off and we will see how bad things are. When I pulled off the intake manifold last night, a thin, oily liquid ran out, it looked pretty dirty in there. Guessing antifreeze mixed with oil came back in through the EGR. That made up my mind to block that off if I do salvage this engine.

I had trouble getting mine out with the VE swap. I dropped the engine, then picked the front of the car off with the hoist and slid the engine out.

Started doing that, but was starting to crush my bumper the way I was trying to lift it. Didn't have any chains handy, so I was using a nylon tow cable (rated at over 2500lbs breaking) looped around the engine. Tried looping it around the front of the car, but that wasn't going to work. Started trying to thread it around the metal supports above/below where the radiator was, decided against that just a few minutes in.

I'll be so happy when I can finally drive the car out of the garage, so I can give both a thorough cleaning.