Sonicfrog Posted October 4, 2006 Share Posted October 4, 2006 What do you guys use to clean and prep the heads... i.e. solutions, techniques, etc. etc. Link to comment Share on other sites More sharing options...
[HTi]Savage Posted October 4, 2006 Share Posted October 4, 2006 U can get a die grinder and some scotch brite wheels. thats what we use at the shop I work at. also brake clean works good. careful not to take off to much material. Use the wheel for aluminum. U just need to get the dry and burned on head gasket material off, u should see a shiney finnish when done. good luck. Link to comment Share on other sites More sharing options...
Roger87ea82t Posted October 4, 2006 Share Posted October 4, 2006 What do you guys use to clean and prep the heads... i.e. solutions, techniques, etc. etc. I would recomend wire brushing the head bolts and chaseing the threads in the block with a bottom tap. Then use engine oil on the bolt threads when you install then to avoid any problems torqueing down the heads.........Roger Link to comment Share on other sites More sharing options...
BoostedBalls Posted October 4, 2006 Share Posted October 4, 2006 Prepping the heads: assuming this is just for a head gasket change? I like to spray them down real good with castrol superclean, then hose them down with the garden hose hooked up to the water heater. This get's rid of most of the muck, then comes the can of carb cleaner. Don't worry too much about drying them out as long as the heads got good and hot, they will dry pretty quick on their own. Compressed air speeds the process. Take a razor-type scraper and take off as much of the head gasket as you can then... I like to take a piece of 180 or 220 sandpaper (or two butted together) and stick it to a piece of glass with spray adhesive. Then move the head on it in a tight figure 8 until the gasket surface is free of all gasket material. This will also tell you if the head is flat or not. This technique can actually get the head flatter than the cutter style head milling machines. The stone machines, on the other hand, get the head the flattest. Combustion chambers with valves installed: I like the synthetic 'wire' wheels that you put on a drill. I prefer the kind that has all the bristles facing down, not the ones that are in a spoke pattern. Once the head is clean and dry, take some water or alcohol, or solvent and fill the ports on one side of the head with the head standing on end. Wait about 30 seconds to see how much leaks past the valves into the combustion chamber. Do this on each side. If the leak is enough to fill a teaspoon in, say, a minute- pull the valve and lap the seat. When the valve is out, check it for buildup on the back side. Then make the call to pull them all out and clean them with a brass wheel brush. Label them so they go back to their original location. Don't use a bead blaster on your heads unless you are going to be tearing them down for a full valve job. That stuff will eat an engine from the inside out. As far as the block: I like to take a riffle cleaning kit with a brass bottle brush and hook it up to a drill. With the engine on the engine stand- tip the engine so that 2 cylinders are facing up and two down. Go to town on the side that is facing down so all of the debris falls onto the floor, then hit it good with compressed air and/or carb cleaner or something to get the rest of the crap out. You don't want anything but clean oil or antiseize compound on your threads when everything goes back together. If you are in doubt, take a bottoming tap and run through the threads. Of course, take the head bolts to the wire wheel and make sure they are perfectly clean. The block threads are like butter, so you don't want to drag anything around in there while you are trying to get the proper torque on them. Good luck! Link to comment Share on other sites More sharing options...
daeron Posted October 4, 2006 Share Posted October 4, 2006 boostedballs: GREAT response, nice and thorough. the sandpaper on the firing deck is a little alarming, though..... i dont know how much I would care to do that, myself...... I get your theory, with the piece of glass to keep it flat, but it still seems a bit frightening.... good point on checking for a true surface though. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 5, 2006 Share Posted October 5, 2006 Personally I just use a razor blade and some castrol super clean or carb cleaner. Then I use a good quantity of brake cleaner to make sure there is no residue of any kind on the surfaces. This is of course if I'm not milling them. I've found that almost every EA series head I've pulled off is warped (unless they have been milled already), and when they come back from my cylinder head guy they are REALLY clean so no worries. I razor blade the block, and chase all the threads in it. As long as it feels smooth and you can see metal, not old gasket debris, you should be fine. GD Link to comment Share on other sites More sharing options...
Sonicfrog Posted October 5, 2006 Author Share Posted October 5, 2006 Great responses! This thread should go in the USRM. Link to comment Share on other sites More sharing options...
BoostedBalls Posted October 5, 2006 Share Posted October 5, 2006 boostedballs: GREAT response, nice and thorough. the sandpaper on the firing deck is a little alarming, though..... i dont know how much I would care to do that, myself...... I get your theory, with the piece of glass to keep it flat, but it still seems a bit frightening.... good point on checking for a true surface though. Yes, I know it sounds crazy but this is how we did jetski heads to keep the compression right for racers. I've done this very procedure to a couple of skis that competed in the Skat Trak World Finals in Lake Havasu City. These engines made it through the race too. And I'll tell ya, those engine are pushing REAL hard on the head gaskets. Our little Subie heads are about the same size and material. I guess we'll see soon enough, I just did mine that way on my ea-82t that I just dropped in the RX, I'll be running over 20psi. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted October 5, 2006 Share Posted October 5, 2006 I guess we'll see soon enough, I just did mine that way on my ea-82t that I just dropped in the RX, I'll be running over 20psi. What you will see is the head gaskets squirting out into an adjacent coolant passage with that kind of boost.... If it doesn't crack the head through to the cooling passage in the exhust port. At that kind of pressure, the combustion temps will be too high for the thickness of the exhaust port wall, and without multi-layer-metal HG's, the pressure will destroy the graphite based stock units. O-ring the block, copper HG's, studs instead of bolts so you can get proper torque, SERIOUS water intercooler, exhaust manifold temp sensors wired into a VERY good engine management system..... maybe you could do it without damage for a little while anyway. GD Link to comment Share on other sites More sharing options...
WheaT_BeeR_MaN Posted October 7, 2006 Share Posted October 7, 2006 y not just spend a little money and take it to a machine shop to do the work and have them reseal the valves. plus take a couple mills off and gain some compression. then it comes back new as ever. also less work. Link to comment Share on other sites More sharing options...
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