ddiddle Posted May 10, 2011 Share Posted May 10, 2011 Well, I've successfully re-lashed the #2 and #4 valves, but the tick is still there. It only ticks after warm up, not while cold. I'm thinking collapsed lifter? Am I thinking correctly? Mike, I might be showing up at your door. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted May 10, 2011 Share Posted May 10, 2011 Curious why you had to relash, unless its a solid cam. Quote Link to comment Share on other sites More sharing options...
waupachino Posted May 10, 2011 Share Posted May 10, 2011 If this is a Hydraulic Cam and you had to re-lash it due to the Rockers becoming loose, you either have a flat Lobe (which is becoming a regular occurrence due to today's Oil), or a collapsed lifter. My bet is on the lobe. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted May 10, 2011 Share Posted May 10, 2011 If this is a Hydraulic Cam and you had to re-lash it due to the Rockers becoming loose, you either have a flat Lobe (which is becoming a regular occurrence due to today's Oil), or a collapsed lifter. My bet is on the lobe. Or the rocker nut backed off. Unfortunately, if the engine was run with slop in the valvetrain, damage to the cam lobe can result. I think the cause is the oil. You HAVE to run an oil rich in zinc in a flat tappet motor or the cam will fail . It happened to me. I reset the lash, started it up and noticed that rocker was only going up and down 1/2 the distance as the others. Cam went flat.......and I was running regular Castrol 10/30 which has like no zinc. Quote Link to comment Share on other sites More sharing options...
amsterdam84 Posted May 11, 2011 Share Posted May 11, 2011 Is there a reason why they no longer put much zinc in todays oils? Is it for environmental reasons or is it to keep costs down. Do todays cars need much zinc and if not is that the reason? Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted May 11, 2011 Share Posted May 11, 2011 Are you sure that it is not an exhaust leak. sometimes they tick like a lifter Quote Link to comment Share on other sites More sharing options...
ddiddle Posted May 11, 2011 Author Share Posted May 11, 2011 I wish it was exhaust. In fact, I was really hoping it was. I've gone over the whole thing with my stethoscope (which looks a lot like a big screwdriver), and it sure sounds like it's coming from within. I also took it to my exhaust guy - we put it up on his rack and he confirmed that, in his opinion, it's internal. I bought the car with the engine supposedly rebuilt and properly broken in. It ran and sounded great up until this spring. I started with the valves because I thought that was the easiest thing to check and correct, but they didn't seem to be loose - loose enough to get clatter anyway. I do confess that I'm at the end of my knowledge and ability though, like that's not obvious. Quote Link to comment Share on other sites More sharing options...
Mike 57 Posted May 11, 2011 Share Posted May 11, 2011 Simple explanation, Zinc or ZDDP (zinc dialkyldithiophosphate) is a high pressure lubricant that helps protect metals sliding against each other like flat tappet lifters and cams. I am trying to think of the last engine to come from the manufacturers with a flat tappet cam. The zinc additive is harmful to catalytic converters and the auto manufacturers got with the oil producers to get rid of the zinc. The put other products in the oil to substitute for the loss of zinc. it may work for cams that are broke in but not new flat tappet cam break in. Quote Link to comment Share on other sites More sharing options...
amsterdam84 Posted May 11, 2011 Share Posted May 11, 2011 Thank you Mike for the explaination. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted May 11, 2011 Share Posted May 11, 2011 Even after the cam is broken in, you still must run oil with zinc to avoid a lobe going flat - or go roller! Quote Link to comment Share on other sites More sharing options...
ddiddle Posted May 12, 2011 Author Share Posted May 12, 2011 Well, due to past work they've done for me and due to a couple true car guys on their staff, I have confidence in a local Chevy dealership. I took the car to them for evaluation. They're saying pretty much what's being said here - either a collapsed lifter or a flat cam lobe due to improper break in by the fellow I bought the car from. Of course they can't know until tear down. Lifter replacement estimated at $1,100.00. A little more, obviously if it's the cam. I'm wondering if this is the time to go ahead a do a mild warming up of the engine, if half of the upper end parts may be replaced anyway. Any counsel? Quote Link to comment Share on other sites More sharing options...
DavidTX Posted May 12, 2011 Share Posted May 12, 2011 Did they have a mask on when they quoted you that price? That is an outrageous charge to replace lifters. That is a 3 hour job at the most and a set of lifters about $100.00. Quote Link to comment Share on other sites More sharing options...
JOHNA01374 Posted May 12, 2011 Share Posted May 12, 2011 If the cam is gone then the entire motor needs to come apart. You'll want to take it all the way down at least as far a pulling the crank but going all the way to a bare block is preferred. At that time you can evaluate the motor and decide if it needs freshing. At the very least you will need new cam, rod and main bearings. Most likely have to turn the Crank and possibly a new oil pump depending on how chewed up it is. I've done a couple of these where we left the pistons in the block because the bores where still perfect but if there is any substantial ring around the top or major scratches in the walls then just tear it down and have it bored. Are you sure this is beyond your abilities. While $1100 is not a huge amount of money it is still a large chunk of change and rebuilding these motors is really pretty simple if you have a decent machine shop around that does quality work. If the bores are ok the a quick hot tank and new cam bearing is usually only a couple of hundred dollars. From there you just put it back together the way it came apart. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted May 12, 2011 Share Posted May 12, 2011 For that price, I would put a roller cam in and do it yourself. Can you get a buddy to help install a new cam? It's really not too difficult, and there are many step by step instructions online. It could be fun project. I would be reluctant to install a new lifter or two on a cam that may be failing. It would suck if the cam lobe had damage and you had to open it up again. I think that since you are in there, replace the cam and lifters as a set, and you will have the peace of mind that its all new - and maybe gain some hp while you are at it! If you go with another flat tappet cam, be sure to break it in properly with the right oil. If you are going to keep the car indefinitely, seriously look into a roller cam. Quote Link to comment Share on other sites More sharing options...
72 LS5 Posted May 12, 2011 Share Posted May 12, 2011 John - why do you say the motor needs to be torn down? If he has good oil pressure, and only two lifters are giving him troubles, the mains and rods should be ok. I've replaced bad cams before without pulling the motor, and driven many thousands of miles afterwards with no issues. Quote Link to comment Share on other sites More sharing options...
JOHNA01374 Posted May 12, 2011 Share Posted May 12, 2011 When a cam lobe or lifter fails it fills the engine with metal shavings. They get into the oil passages and spread throughout the motor. In every cam failure I've seen or had to fix (6 I think) the main and rod bearings where junk and crank needed to be turned. I always had the cam bearings replaced as a precaution. If the mains are bad I can only guess the cam bearings would be as well. We've tried to clean a block at home after a failure but kept getting misc metal shaving out of it no matter how much we power washed and scrubbed so a hot tank is worth the $40 most places ask. You can make the job a little easier by leaving the pistons and rods in the motor IF the bores are ok. This will great reduce the re-assembly time and you know everything is in the right holes. As for a new cam. I would only go with a roller if you can truly afford it. It's a hard pill to swallow for a lot of folks these days. I've been running flat cams since I built my first motor back with I was a kid and only had one fail and that was completely my fault. ZDDP is an absolute must regardless of what oil you use. I always recommend 2 bottles for break in then a drain and refill with another bottle. As I mentioned I have done a few rebuilds due to flat cam but in every case it was the owners fault. Three of the motors belonged to friends that bought new (old) cars and did an oil change forgetting to add ZDDP. One other was a guy that changed the oil on the road (major leak on road trip) and though he could "getaway" with the 400 mile drive home without the additive. By the time he got home the cam was gone and oil that came out of the car looked like glitter. I too have done a quick cam and lifter swap after one failed and drove for several thousand miles but I my opinion it's not the "correct" way to do it and I don't want to give my fellow members any advise that could come back to bite me later. The main and rod bearing on that motor where junk as well when I finally tore it down after about 10K miles. It started loosing oil pressure when warm so it was a sign the clearances where loose. Quote Link to comment Share on other sites More sharing options...
1972mc Posted May 28, 2011 Share Posted May 28, 2011 Recently attended a clinic for my other car (Buick Grand National), and they could not have been more vehement about the necessity of ZDDP in all flat tappet engines. Like has been said, the oil had zinc removed a few years ago and we are left unprotected. It is going in all my v8's. Also was told that synthetics will drain off the metal and will not leave a layer of protection like dinosaur oils. This is especially bad for those of us that do not drive our cars on a regular basis. BTW my Buick with 86K miles has a wiped lobe (2 of them), after owner ran mobil 1 synthetic for the last few years. Lots of metal shavings, wrecked mains etc... She is all apart in prep for a total rebuild. Carl Quote Link to comment Share on other sites More sharing options...
MonteFox89 Posted June 1, 2011 Share Posted June 1, 2011 hey, sorry to butt in and steal the topic but... are there any oils at all that have ZDDP in them still to at least make things a little better? Quote Link to comment Share on other sites More sharing options...
amsterdam84 Posted June 1, 2011 Share Posted June 1, 2011 Isn't there a Rotella product with zinc in it? Quote Link to comment Share on other sites More sharing options...
MonteFox89 Posted June 1, 2011 Share Posted June 1, 2011 http://www.barsproducts.com/4401.htm?gclid=CLr2uputlakCFRlPgwod-A1Wdw http://www.mobiloil.com/usa-english/motoroil/car_care/askmobil/ZDDP_Levels_Classic_Cars.aspx I found this a minute ago lol Quote Link to comment Share on other sites More sharing options...
71monteme Posted June 2, 2011 Share Posted June 2, 2011 hey, sorry to butt in and steal the topic but... are there any oils at all that have ZDDP in them still to at least make things a little better? here you go. thanh Quote Link to comment Share on other sites More sharing options...
wallaby Posted June 2, 2011 Share Posted June 2, 2011 it used to be that diesel oils like Rotella had zinc in them, but even those have had the zinc phased out. All the newer diesel engines have catalytic converters...zinc ruins them. In my area, the only "off the shelf" oil that has zinc is the Valvoline racing oil. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted June 3, 2011 Share Posted June 3, 2011 hey, sorry to butt in and steal the topic but... are there any oils at all that have ZDDP in them still to at least make things a little better? Read on lots of info: hemmings article Quote Link to comment Share on other sites More sharing options...
ddiddle Posted June 13, 2011 Author Share Posted June 13, 2011 Dropped her off at Kennedy Performance in Lexington today to get to the bottom of this noise. I'll keep you posted. He's not thinking cam, so we'll see. Quote Link to comment Share on other sites More sharing options...
ddiddle Posted June 17, 2011 Author Share Posted June 17, 2011 Well, according to my mechanic, the tick is coming, not from the valvetrain per se, but from the fuel pump pushrod. Apparently it's just a bit too short caused, possibly, by a failed cam lobe or an incorrect cam installation. In trying a new pump and rod, the noise was worse due to the new rod being thinner than the old one and slapping around in there a bit. Anyway, it's all coming apart to check the cam and likely installing a little hotter cam. We'll also clean and paint everything and maybe get rid of the edelbrock and install a Q-jet, depending on what we find inside and how many of my children I have to sell to get it done. Man, I really admire you guys who can do all this stuff yourself. I can build a house, but I can't fix this lousy tick. I'll keep you posted, in case anyone's interested. On this nice day, take a drive for me while mine's all torn apart. Quote Link to comment Share on other sites More sharing options...
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