nipper Posted July 15, 2009 Share Posted July 15, 2009 There have been two very common reasons for repeat HG failures of subarus. One is use of non-subaru HG's. the other is not refinishing the heads (or milling if you will). I would never do a customers car without sending it to a machine shop for cleaning up the surface at the very least. Thats water under the bridge now, what is done is done. Vacume gauges are really cheap, if you dont have a good compression gauge rent one. As long as it screws into the spark plug hole i'm happy with it. If the numbers are very high the timing is off. Do a dry/wet compression test. Do the vacume test first, as that may just answer our questions. good luck nipper Link to comment Share on other sites More sharing options...
littlecars Posted July 15, 2009 Author Share Posted July 15, 2009 heres a link to a photobucket page of pictures. I hope this works, this is the first time I have ever used photobucket: http://s983.photobucket.com/albums/ae316/littlecars123/ Link to comment Share on other sites More sharing options...
Log1call Posted July 15, 2009 Share Posted July 15, 2009 Once you have the heads off, it is false economy not to lap the valves. They need to come out anyway to ensure the heaads are clean when you put them back on. You can not ensure they are spotless if the valves are still in there. If the valves don't really need a lapping in... then it only takes a minute each valve to clean them up with the paste. If though, when you start to lap them in, you find a pit or warped valve, then it is just as well you are doing it, even though it is going to take several minutes for each valve. It is the difference between being thorough and not, between a good job and a poor one. Once you have lapped and polished the valves you can fit the new valve guide seals and it is all good for the next hundred thousand miles. Link to comment Share on other sites More sharing options...
mdjdc Posted July 15, 2009 Share Posted July 15, 2009 You said that you didn't take the intake off the engine, but just unbolted it. I am willing to bet that you have a small piece of intake gasket left over stuck to the intake and it is causing a vaccuum leak. On one car that I did, I mistakenly forgot to check the surface and it had some gasket left on it. It ran just the way you describe. If I were you, I'd unbolt the intake, lift it up and thouroughly inspect the mating surface. Scrape off any gasket material and then bolt it back down. I bet your problem will be gone. It should only take you about an hour to do this and you may have the answer to your problem. Do this before you do anything else and save yourself some time and money. Link to comment Share on other sites More sharing options...
davebugs Posted July 15, 2009 Share Posted July 15, 2009 Those pics look good. Cam sprockets are definately correct. Drivers side cam sprocket hash marks are often a little off. I use white nail polish to mark the hash marks everywhere. Costs a buck and dries fast even in cold weather. I always use new intake gaskets and assess the old ones looking for material missing so mdjdc may be on to something. I also always flat file the exhaust Y-pipe and use new gaskets there (both Felpro usually). When on the stand I always spin it to look at intake mating surfaces, check the oil pan, ,etc. It's acting an awful lot like the TB, but it looks good in the pics. I have no expertise with a vacuum gauge but it sounds like you may need to develope some expertise with one. Gotta run. Link to comment Share on other sites More sharing options...
OB99W Posted July 15, 2009 Share Posted July 15, 2009 Are you sure the injector wires are connected properly, and to the right place. Littlecars, I didn't see any response from you to what Log1call said about the injector wiring. You did say that you only lifted the intake, so perhaps you never disconnected the injectors. It's easy to accidentally reverse the connections to #2 and #4, but it's also easy to check. White tape on the wires at the connector usually marks #2, while #4 is black. Otherwise, I agree with those who have suggested that vacuum and compression testing can help pinpoint the problem without tearing everything down. What mdjdc mentioned about the intake gasket also merits checking. Link to comment Share on other sites More sharing options...
johnceggleston Posted July 15, 2009 Share Posted July 15, 2009 (edited) thanks for the pics. you're right, the timing belt looks dead on. Edited July 15, 2009 by johnceggleston Link to comment Share on other sites More sharing options...
johnceggleston Posted July 15, 2009 Share Posted July 15, 2009 You said that you didn't take the intake off the engine, but just unbolted it. I am willing to bet that you have a small piece of intake gasket left over stuck to the intake and it is causing a vaccuum leak. On one car that I did, I mistakenly forgot to check the surface and it had some gasket left on it. It ran just the way you describe. If I were you, I'd unbolt the intake, lift it up and thouroughly inspect the mating surface. Scrape off any gasket material and then bolt it back down. I bet your problem will be gone. It should only take you about an hour to do this and you may have the answer to your problem. Do this before you do anything else and save yourself some time and money. i like this one, it matches the symptoms of vacuum leak. Link to comment Share on other sites More sharing options...
littlecars Posted July 15, 2009 Author Share Posted July 15, 2009 I throughly cleaned and flat filed the intake/head surface. and used a new gasket. I did not disconnect the injector wires. they are definatly in the right spot. Link to comment Share on other sites More sharing options...
mdjdc Posted July 15, 2009 Share Posted July 15, 2009 I am talking about the surface on the bottom of the intake not the intake surface on the head itself. Did you clean that really well. Flat filing may have been too much. All you needed was to use a scraper and possibly some 3m scotch brite to clean the surface. You definitely do not want to go too heavy as with a file. It can leave scratches that will lead to leaks. Link to comment Share on other sites More sharing options...
Gloyale Posted July 15, 2009 Share Posted July 15, 2009 Once you have the heads off, it is false economy not to lap the valves. They need to come out anyway to ensure the heaads are clean when you put them back on. You can not ensure they are spotless if the valves are still in there. If the valves don't really need a lapping in... then it only takes a minute each valve to clean them up with the paste. If though, when you start to lap them in, you find a pit or warped valve, then it is just as well you are doing it, even though it is going to take several minutes for each valve. It is the difference between being thorough and not, between a good job and a poor one. Once you have lapped and polished the valves you can fit the new valve guide seals and it is all good for the next hundred thousand miles. I respectfully disagree. First off, have you ever tried removing vavles from a DOHC 2.5 head? there is no room for a conventional vavle spring compressor. Have to Fab or buy a special lever type with a snout that will fit down into the lifter buckets And why do they need to be spotless? only the mating surface is critical to be totally clean, the insides of the ports can have some carbon or varnishing and it doesn't hurt anything(unless it's excessive) I hot tank heads with vavles in them all the time and they come out very clean. Unless you are burning oil under vacuum load, or have a bad leakdown test, I see no reason to do a valve job. Espescially if you aren't going to change the Rings or Crank/Rod bearings. I wouldn't touch the valves unless I was rebuilding the entire rest of the motor or there was evidence of damage or defect. Link to comment Share on other sites More sharing options...
littlecars Posted July 16, 2009 Author Share Posted July 16, 2009 O.K., I just checked the vacumm. It is bouncing between 18" and 21". does that mean a valve problem? I am not going to have time to do a compresson check for a few days probably. I will let you know what I come up with. Link to comment Share on other sites More sharing options...
nipper Posted July 16, 2009 Share Posted July 16, 2009 O.K., I just checked the vacumm. It is bouncing between 18" and 21". does that mean a valve problem? I am not going to have time to do a compresson check for a few days probably. I will let you know what I come up with. Poor valve seating if it does that all RPMS. If it does it just at idle leaking HG. nipper Link to comment Share on other sites More sharing options...
littlecars Posted July 16, 2009 Author Share Posted July 16, 2009 At this point, will it do me any good to do a compresson check? I guess it might show me weather it is #2 or #4 is where the problem is? I have to replace the head gaskets anywheys and I will pull the valves out this time and check them for straitness and lap them. This explains the rough idle. Link to comment Share on other sites More sharing options...
littlecars Posted July 16, 2009 Author Share Posted July 16, 2009 I think I might try to to the HG's with the motor in this time. What do you think? Link to comment Share on other sites More sharing options...
davebugs Posted July 16, 2009 Share Posted July 16, 2009 Just curious. If you redo the HG and hopefully use a Suby one tell us how different the torque procedure is. Personally I'd pull the engine again (should be much quicker this time) and do both HG's again. I mean if you already have trouble with one, I'd think the second one was suspect. Link to comment Share on other sites More sharing options...
mdjdc Posted July 16, 2009 Share Posted July 16, 2009 Do Not try to do this with the engine in the car. If you drop one or more of the lifter buckets on the ground and get the position messed up you will have nothing but trouble. By the way, did you keep all of the lifters in the same position as original or did you just put them in any old way. If you mixed up the intake and exhaust lifters there is yor problem. you will have lifters holding the valves open and hence a misfire. You are new at this and I will tell you that you need to be very careful and exact as to what you are disassembling and how to reassemble things. Also, I am getting the feeling that you only did one HG. It just isn't worth the time to pull the engine if you are only going to do one side. Do them both. Hopefully my perception is wrong. Link to comment Share on other sites More sharing options...
nipper Posted July 16, 2009 Share Posted July 16, 2009 Two general rules of themb for any heavy engine work. 1- Cleanliness is next to godleness, and begin clean working on an engine is akin to sitting on God's moms lap. 2- Unless the part is being replaced, everything goes back to where it came from, the only exception are the fasteners, though I know people who even tag the Major bolts and pu them back where they came from (nothing wrong with that). You can never be to anal retnetive when doing major work. At this point I would just dig into it, as I am satsified with the vac gauge test. Also if you did put the wrong lifter in the wrong spot, you may now need a valve job (which I would have done to begin with). nipper Link to comment Share on other sites More sharing options...
littlecars Posted July 17, 2009 Author Share Posted July 17, 2009 O.K. I will pull the motor again. I made sure I put the lifters in the right spot. I marked then wih a grease pencil as I took them out. I put them back exactly the same way. but since we are on this topic, can I verify this with a fealer gauge and check the gap? I did do both head gaskets and I will do both again. I will also do a valve job this time Your right, I am new at this. subarus that is. I have done several chevy 350 rebiulds, a few automatice tranny rebiulds, 2 or 3 toyota 22r head gaskets. I grew up on a farm working on tractors and stuff since I was a kid. almost exclusivly old carberated stuff. Nothing like a late model car thought. now I am a Automation/millright mechanic. It is like being a car mechanic but I fix rotory machinery, gear boxes, stuff like that at a oil refinery. So I am used to taking things apart very miticulacly and putting them back together exactly the same way. I am a fairly experianced machanic, way above the average "weekend warrior". but I am definitly not a automotive machanic, that is why I am hear. to ask all of you the questions that I do not know how to answer. I am glad I stumbled across this forum, I am thankfull for all the great help, advice and information that I have recieved and I am looking farward to being a member for a long time. Link to comment Share on other sites More sharing options...
nipper Posted July 17, 2009 Share Posted July 17, 2009 Yay you have a great skillset. The only other caution I have is when you get the HG's from subaru, follow the torquing sequence someplace on www.endwrench.com in the archives under engine. They can be touchy. I too have worked on chevy. fords, AMC and mopars. Back when they were all so very forgiving. BTW check the seperator plate in back of the engine. If it is plastic replace it with a metal one. Also put in a new PCV valve. nipper Link to comment Share on other sites More sharing options...
littlecars Posted July 21, 2009 Author Share Posted July 21, 2009 I just dropped the heads off to have the valve job done, becouse I didnt want to have a spring compressor. They just called me and said all the exhoust valve need replacing, they are hour glassed. They said this is very common. Is this true? Good thing you talked me into getting a valve job, or I would need a new motor when one broke!!!! Link to comment Share on other sites More sharing options...
davebugs Posted July 21, 2009 Share Posted July 21, 2009 Well then. Things are looking up. Get the proper gaskets and torque sequence and you should be good for another 100k or so. Link to comment Share on other sites More sharing options...
Log1call Posted July 21, 2009 Share Posted July 21, 2009 Gloyale. Yes I have worked on these motors and yes the valves can be a little inconvenient to get out. That is no reason not to do them though. Cleanliness, along with being through, is absolutely critical to getting perfect results every time. Link to comment Share on other sites More sharing options...
littlecars Posted August 2, 2009 Author Share Posted August 2, 2009 O.K. I just finished the car. It runs great now but...... Now it is getting hot. At first i let it idle for about 15 minutes then it started to get a little warmer than normal. I turned the heater on and it blew cold. I checked both radiator fans and they were both on. The radiator cap was cold so I took it off, it was a little low on water. I figured this was becouse there were air bubbles. I topped it off and let it idle for 30 minutes. I kept getting air bubbles, then I would top it 0ff with water. After about 30 min. there were no more air bubbles. I put the cap on and drove it. Now the heater works! After a few miles it starts to get hot again. I checked the radiator cap and it was cold. The upper rad. hose was hot and the lower hose is cold. Any idea what is wrong? I replaced the water pump and thermistat when the motor was out. I know I did not put the thermistate in backwards? Link to comment Share on other sites More sharing options...
davebugs Posted August 2, 2009 Share Posted August 2, 2009 Part of the beauty of an OEM thermostat is that I don't think you can install it backwards. Of atleast is should be really, really obvious that it didn't go that way. Did you follow the burping instructions here? Including filling through the top hose? Link to comment Share on other sites More sharing options...
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