Dirk Posted November 9, 2009 Share Posted November 9, 2009 So I have a sloppy wrist pin. My question is: Where is the wear likely to be? If the wear is in the pin itself or even the piston then I may be able to rectify the problem by simply removing the head to gain access. If the wear is in the connecting rod, then it looks like another complete re-build. I would like it to be the first option however I am reluctant to start removing heads without being at least 80% sure that the issue lies there and not in the rod. Comments and opinions please? Link to comment Share on other sites More sharing options...
backwoodsboy Posted November 9, 2009 Share Posted November 9, 2009 (edited) Dirk, What motor are we talking about? Im guessing EA71 or EA81 from where youre posting. As far as I can see, you wont know WHERE the wear is until you pop that piston out to see. BUT if one is worn, Id be willing to bet theres wear on the other surface as well. If you get the head off, and have to go deeper into the motor to fix the problem, the heads have to come off to split the case ANYWAY. (sounds like youve been into this engine before?) If your motor is worn enough to have a sloppy pin or piston, I would recommend a full case-split rebuild anyway. I would personally pull the engine out and go to town (AFTER I was sure it wasnt just piston slap) Edited November 9, 2009 by backwoodsboy Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 9, 2009 Share Posted November 9, 2009 How did you diagnose a wrist pin without even pulling the head off? GD Link to comment Share on other sites More sharing options...
Dirk Posted November 9, 2009 Author Share Posted November 9, 2009 Cheers Backwoodsboy. Yes it is an EA71 and yes I did do a full rebuild less than two years ago but I did not replace the wrist pins. Had I noticed any slack around the pin I would have done something about it. Unfortunately I did not measure the clearance scientificaly which could be my undoing. The cylinders were in good condition. If it were piston slap would I have seen any obvious signs? I have learned recently that I am not the first to have re-built this engine. Makes me wonder if the heads have been skimmed one too many times or cylinders honed one too many times. I know where I can get over sized pistons so if I choose to go the long route at least I am tooled up for it. I won't happen in a hurry though since I don't have a pot to piss in right now. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 9, 2009 Share Posted November 9, 2009 1: Could it need a valve adjustment? Every 15,000 on that engine.... 2: If the cylinder's have been honed more than once, chances are good that you should be chucking that block in the recycle if it's anything major. Being an all-alumiunium engine, you can't bore them without a bore-plate that simulates the heads being torqued in place. These engines have a tendancy to spin liners if they are bored any other way. 3. Being it's been honed several times.... you may indeed be hearing piston slap as the skirts rock in the cylinder. 4. I have yet to see a wrist pin failure. Rod bearings are the most common internal failure. GD Link to comment Share on other sites More sharing options...
Dirk Posted November 9, 2009 Author Share Posted November 9, 2009 Hello GD. Thanks for input. Can you check this thread out and tell me if I was heading in the right direction? http://www.ultimatesubaru.org/forum/showthread.php?t=105417 Cheers Dirk Link to comment Share on other sites More sharing options...
ihscout54 Posted November 10, 2009 Share Posted November 10, 2009 Wrist pin its self or not, you will likely require the parts I mentioned as you have already narrowed the trouble down to that cyl. If it is not the bores. No matter what you will most likely have to pull this motor again when you are ready to remidy this issue Heres some food for thought. You have recently been through this engine (which was making the same noise befor the rebuild), and you did not mention any damage to the pistons or their bores. I also assume you spec'd the cyls. A rod bearing does not sound like a ping and may cause oil pressure issues. If it was valve/cam related it would still make a noise with the plug wire pulled. GD is 100% correct piston slap is a possibillity, but again Ide think youd have noticed some signs of that during the tear down, but it could have been missed. A screwed up rod bushing or an out of spec pin bore on the piston could be easy to miss especially if the wrist pin looked fair. Maybe a pin oiler hole was plugged, and caused improper wear. For all I know it is a bad plug wire arking on the block. It could even be that pulling the plug wire chnges the rythm of the sound enough that it muffles it. My opinion on your noise is 100% speculation, as I cannot hear it, but what you describe gave me the wrist pin vibe. Is this noise pretty loud? Did you replace the rod bushings? Compression check was good? Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 Hello ihscout54 Thanks for the additional input. As you can see I have been asking questions at a prolific rate over the past few days in order to get as much info as possible and maybe retrieve a definitive answer. I don't think that answer will really become clear to me untill things either get worse or I re-build. In answer to your other questions: A recent compression check showed good and perfectly equal in all cylinders. The entire ignition system is new except for the distributor body. The noise is really not that loud. I can't hear it at all when driving. Only at idle and very light acceleration. The noise is quite bearable at normal operating temperature but gets more louder distinct if the engine is allowed to get warmer. But even then it doesn't sound that dramatic. I have lived with it for the last 4 years and it hasn't got any worse so guess it can wait a little longer With all the information I have collected over the past few days, I think I have decided to find a later model EA71 and re-build it in my own sweet time. Subarus of all ages are quite common here so I will have plenty to choose from. Thanks so much to you and GD and others for sharing your wealth of information and for being so patient with an ameteur and somewhat agricultural mechanic. Link to comment Share on other sites More sharing options...
ihscout54 Posted November 10, 2009 Share Posted November 10, 2009 Youre questions are definately welcomed! The only reason I post is that I have had a number of questions answered by this board and its only fair that I contribute Anyways 4 years... Yea you have time. If the engine type you have is readily availible Ide buid one while driving. The only draw back Ive had is its hard to find a core thats worth a crap. Like you said: "find the latest model ea71" with the top mounted starter (if thats what you have). I just wanted to make sure you knew I wasnt telling you it was a wrist pin for sure, as I am not sure. BTW you cant be that much of an amateur, not everyone can rebuild their own engine. Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 (edited) Thanks for the kind comments. But Luckily for me and my family I am a much better joiner/carpenter than a mechanic. I know its a little late in the day for this but it has just occured to me that I have forgotten to mention two curious symptoms. Firstly, There have been a notable number of days when the noise has not been present at all. The good days! Secondly, When the car is at idle and stationary on a steep incline the noise at times has appeared to be louder and more mechanical. I can't tell you if this fact or if perhaps it has been more psychological. But I guess its worth mentioning. Edited November 10, 2009 by Dirk missing data Link to comment Share on other sites More sharing options...
ihscout54 Posted November 10, 2009 Share Posted November 10, 2009 (edited) I might put a mech oil pressure gauge on it just for fun. I know for a fact that my mood can eliminate or enhance any flaw from a rough idle to an engine noise. But thats interesting. If it is a rod bearing it should be most pronounced under load maybe even being lugged a bit. Piston slap could be kinda intermitant I suppose, but then again an issue with the rod bushing/wrist pin might be too. Especially if there is an oiling issue with that pin. Ill mention one more thing, both my roos have a odd faint rod like noise mostly when cold, I was concerned about it till I got the other car and it made a similar noise. Its pretty faint, and I noticed it sounds nasty inside the car, but really faint under the hood. Been that way for 3+ years so, some old stuff is noisy and some owners are paranoid. Edited November 10, 2009 by ihscout54 Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 Engine Flush? Link to comment Share on other sites More sharing options...
ihscout54 Posted November 10, 2009 Share Posted November 10, 2009 At this point it probably wouldt do any good. I just cant get over the fact that you recently built this engine inc new bearings, crank grind, etc. I still say rod bushing/wrist pin. Keep thinking on it maybe more details will come. Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 No crank grind. Stock bearing shells went back in as well as stock piston rings. Basically the consumable items (bearings and seals) were all replaced with standard replacements. All other components are origional. Cylinders were honed (very little wear was present) Heads were skimmed, valves re-ground and seated. As I said before, I did check all tolerances against my Haynes manual to the best of my ability and only with the tools I had available to me. e.g. feeler gauges and a vernier caliper. The condition of the cylinders was checked out by the mechanic who honed them. Thought I better make it clear exactly what was done. And in writing thhis it is clear to me how many variables there still are. Link to comment Share on other sites More sharing options...
GeneralDisorder Posted November 10, 2009 Share Posted November 10, 2009 Hhhhmmm - you can't really take a measurement of a crank journal effectively with a caliper. They won't give you a repeatable, accurate reading. Also the fit of the crank to the bearings (mains and rods) should ALWAYS be double checked with plasti-gauge. More than once in the history of engine rebuilds has a replacement part been mis-packaged. One oversized rod bearing insert and the whole game is lost..... The tollerances on these engines are quite close. You really need to measure crank journals with a metric micrometer. Trouble with sae measureing devices is they measure typically down to .001" - which is larger than .01mm.... metric mic's and dial indicators are actually more accurate (and typically more expensive here in the US) than their sae counterparts. A metric mic., telescoping gauge set, and plasti-gauge should be on the "must have" list for rebuilding these engines. A bore gauge is nice too but an inside mic. will also do the job if you are careful. It is expensive stuff, but how much is it worth to only have to do the job one time? GD Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 This is true. I am simply not tooled up correctly to be able to check these things properly but to be fair this is just a hobby for me and I actually get a kick out of doing it on a shoe string budget. The last re-build cost me less than $400 dollars all up which is pretty cheap fun as far as i'm concerned. Learning by making mistakes is always fun because you get to see first hand what happens if something is not right. As long as no one gets hurt. I think I will shop around a bit for the next likely candidate and then take my time to get it as good as I can within my limits. It won't be perfect, but it might end up close. I'm sure there is a later Ea71 with hydraulic valves that has a little extra power. Sure I can track one down. Link to comment Share on other sites More sharing options...
Gloyale Posted November 10, 2009 Share Posted November 10, 2009 This is true. I am simply not tooled up correctly to be able to check these things properly but to be fair this is just a hobby for me and I actually get a kick out of doing it on a shoe string budget. The last re-build cost me less than $400 dollars all up which is pretty cheap fun as far as i'm concerned. Learning by making mistakes is always fun because you get to see first hand what happens if something is not right. As long as no one gets hurt. I think I will shop around a bit for the next likely candidate and then take my time to get it as good as I can within my limits. It won't be perfect, but it might end up close. I'm sure there is a later Ea71 with hydraulic valves that has a little extra power. Sure I can track one down. Where are you located? I've got a few EA71s sitting on the floor of the shop. One runner and 2 cores. PM me. Link to comment Share on other sites More sharing options...
ihscout54 Posted November 10, 2009 Share Posted November 10, 2009 I think hes in New Zeland. Link to comment Share on other sites More sharing options...
Dirk Posted November 10, 2009 Author Share Posted November 10, 2009 Yes I lve in the south island of New Zealand. Thanks for the offer though. Subarus are pretty much staple diet of car here. And the ubiquitous HILUX. I live in a very transient town. Lots of visitors come through for the summer and winter seasons and then ditch there cars when they have to leave. Ski season ended not long ago so the scrap yards are full of old bangers that have been abused up and down the mountains. Just have to sift throught the crap to find the pearl. Link to comment Share on other sites More sharing options...
Dirk Posted October 1, 2011 Author Share Posted October 1, 2011 UPDATE: See this thread http://www.ultimatesubaru.org/forum/showthread.php?p=1047585#post1047585 Link to comment Share on other sites More sharing options...
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