suprafan72 Posted July 2, 2007 Share Posted July 2, 2007 Im afriad i had a very unentertaining visit to the Dyno today... on the way over i noticed my Egt's were very high i.e on a 3rpm cruise 800 deg and WOT runs around 960 deg which i was a little uneasy with.. Did a compression test 1. 160 2. 75 but with an extra 3 pumps 125 3. 160 4. 160 5.155 6.160 Looked at the piston crowns and bores with the boroscope and all looked all ok. Did a cycliner leakdown test, no 2 40% and you could hear the hissing through the back on the exhaust.. So new exhaust valves and cylinder head skimmed i guess... May as well do the Valve stem seals as well well im at it.. Whilst the head us off, is it worth doing anything else? Link to comment Share on other sites More sharing options...
AshBhp Posted July 2, 2007 Share Posted July 2, 2007 Sad to here that, if you have stock valve springs change to uprated ones. Link to comment Share on other sites More sharing options...
Chris Wilson Posted July 2, 2007 Share Posted July 2, 2007 Skimming the head and exhaust valve leakage are not USUALLY inclusive. Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 Hmmm, I know this isn't related to the topic, but it is the 2nd time I've noticed someone having hassles with no 2 cylinder.. Is this perhaps the weak one on the 2JZ? Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2007 Share Posted July 2, 2007 Hmmm, I know this isn't related to the topic, but it is the 2nd time I've noticed someone having hassles with no 2 cylinder.. Is this perhaps the weak one on the 2JZ? I discussed this with Mark (Phoenix) while he was doing a leakdown test on my engine. According to him No5 is by far the most common to have issues, followed by 6, then 4,3,2,1 in that order. Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 No 5 from which way?? bear in mind 5 and 2 are 1 away from the end of the block... I know the proper way of doing it, but not everyone counts them the same way... My dad and I ended up almost killing each other when I was building his MG Aseries lump and he kept starting from the opposite side, which makes it interesting when you are trying to do a 1-4-3-2 timing check *grin* Link to comment Share on other sites More sharing options...
suprafan72 Posted July 2, 2007 Author Share Posted July 2, 2007 it has titanium springs... What could cause this issue? lean mapping? Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 Has there been any work done on the head previously? It could be something as simple as the valves not ground in properly.. Link to comment Share on other sites More sharing options...
suprafan72 Posted July 2, 2007 Author Share Posted July 2, 2007 Has there been any work done on the head previously? It could be something as simple as the valves not ground in properly.. Yes its had head work done to it before... a month back, the compression was fine ona all cylinders.... Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 If you are going to do the valve stem seals, I would get the valve seats checked, and then regrind the valves in, just make sure you have enough material to do it. Perhaps do the head properly, and get it swirl polished on the intakes and get the shim gaps checked and if required reshimmed. Do it once, do it right. Link to comment Share on other sites More sharing options...
AshBhp Posted July 2, 2007 Share Posted July 2, 2007 it has titanium springs... What could cause this issue? lean mapping? Titanium springs, you sure? I'm thinking valve bounce. Soon as head's of, all will be reveled. Link to comment Share on other sites More sharing options...
suprafan72 Posted July 2, 2007 Author Share Posted July 2, 2007 Well so i've been told? and what the spec says.. but we will see... Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 Well so i've been told? and what the spec says.. but we will see... Keep us informed please.... Link to comment Share on other sites More sharing options...
suprafan72 Posted July 2, 2007 Author Share Posted July 2, 2007 Keep us informed please.... Will do.. going to get onto it in the next week or so.. and get it done ready for JAE. Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2007 Share Posted July 2, 2007 No 5 from which way?? bear in mind 5 and 2 are 1 away from the end of the block... I know the proper way of doing it, but not everyone counts them the same way... My dad and I ended up almost killing each other when I was building his MG Aseries lump and he kept starting from the opposite side, which makes it interesting when you are trying to do a 1-4-3-2 timing check *grin* Sorry Gav, I mean the traditional way of numbering the cylinders on the 2JZ, 1 being at the front, 6 at the back. Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 Sorry Gav, I mean the traditional way of numbering the cylinders on the 2JZ, 1 being at the front, 6 at the back. Wasn't having a go at all dude, just pointing out some people do it the wrong way and it causes all sorts of probs when referring to the cylinders. Just trying to work out if there is any commonality.. Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2007 Share Posted July 2, 2007 If you are going to do the valve stem seals, I would get the valve seats checked, and then regrind the valves in, just make sure you have enough material to do it. When I was speaking to Mark (Phoenix) about my possible valve issue he said that all that would be a must. He was talking about £800 all in inc labour and parts. Link to comment Share on other sites More sharing options...
Homer Posted July 2, 2007 Share Posted July 2, 2007 Wasn't having a go at all dude, just pointing out some people do it the wrong way and it causes all sorts of probs when referring to the cylinders. Just trying to work out if there is any commonality.. It wasn't taken that way at all mate! was in a rush typing and forgot the formalities Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 When I was speaking to Mark (Phoenix) about my possible valve issue he said that all that would be a must. He was talking about £800 all in inc labour and parts. Now this opens up an interesting point, if you are going to get the valve seats done, is it worth considering oversized valves and a 3 angle cut? I have no idea what it would cost for the above mentioned, but it could be worthwhile considering. Link to comment Share on other sites More sharing options...
JustGav Posted July 2, 2007 Share Posted July 2, 2007 It wasn't taken that way at all mate! was in a rush typing and forgot the formalities There are somethings which father and son no longer do... a) putting tv aerials after he left me on the roof for throwing my phone at him in a stress... b) wiring up a-series igntion leads after he constantly kept getting the cylinders the wrong way round and I couldn't work out why the damn thing wouldn't fire properly on 1-4-3-2, till I did a 4-1-2-3 configuration over the phone. Link to comment Share on other sites More sharing options...
JohnA Posted July 3, 2007 Share Posted July 3, 2007 ...2. 75 but with an extra 3 pumps 125 ... This would lead me to further investigate piston ring issues Looked at the piston crowns and bores with the boroscope and all looked all ok. Would you see mild scuffing on the cyl walls? Did a cycliner leakdown test, no 2 40% and you could hear the hissing through the back on the exhaust.. Did you hear any such noise from any of the other cylinders (ie is that hissing unique to that cylinder?) Link to comment Share on other sites More sharing options...
suprafan72 Posted July 3, 2007 Author Share Posted July 3, 2007 This would lead me to further investigate piston ring issues Point took.. Will investigate.. but i know there is no smoking or any excess oil usage to indicated broken rings. Would you see mild scuffing on the cyl walls? Not sure.. Did you hear any such noise from any of the other cylinders (ie is that hissing unique to that cylinder?) No "No" Link to comment Share on other sites More sharing options...
JohnA Posted July 3, 2007 Share Posted July 3, 2007 From my experience valves don't just give way like that, except if something breaks or hadn't been assembled correctly during a rebuild. Did you ever check the valve clearances? (anything to avoid taking the head off!) Link to comment Share on other sites More sharing options...
suprafan72 Posted July 3, 2007 Author Share Posted July 3, 2007 The only reason i noticed this was purely down to my egt gauge... the car runs spot on apart from that.... starts well, idles, well performs very well on full load and off boost.... no smoking...... Looking extensivly at the pistons, crowns etc.. everything is spot on... all cylinders apart from no 2 on leakdown are fine... So its very mysterious and can't explain it! Its a good excuse to take the head off anyway to do some polishing etc etc...so im not that gutted really. Link to comment Share on other sites More sharing options...
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