ricky Posted June 5, 2011 Report Share Posted June 5, 2011 Hey guys I need a cam I'm in Sacramento call or text or pm 916-690-5587. Need asap Link to comment
Chris#51EPGraham Posted June 8, 2011 Report Share Posted June 8, 2011 Any idea why it broke? The towers often go a little out of alignment, but never heard of them going out far enough to break a cam. I've only got L16 cams + one L18, matched rockers, older ones cheap. Link to comment
Skib Posted June 8, 2011 Report Share Posted June 8, 2011 The towers often go a little out of alignment, but never heard of them going out far enough to break a cam. lol most destroyed one Iv seen so far :lol: VVV Link to comment
DREWSDIME Posted June 8, 2011 Report Share Posted June 8, 2011 What is the number on the cam, maybe I have one. Link to comment
banzai510(hainz) Posted June 8, 2011 Report Share Posted June 8, 2011 I think it would be faster to just bolt up anther head on there and say Fuck it. Get another head. dial to TDC Dial block to TDC and pull old head and replace. head is going to come off any to put that cam in correctly anyways. Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 The cam that was in the the l20 said 210 on it. I had an l20 cam in my old l16 that was rebuilt with head. I pulled the towers and cam off and used that the lobes on cam are about .050 bigger then old cam. The cam towers seen to be ba on old cam. I put new cam in old towers and I could not spin it with even with out litters so I think the towers were to tight and that Is why it broke. Link to comment
banzai510(hainz) Posted June 8, 2011 Report Share Posted June 8, 2011 I could not spin it with even with out litters so I think the towers were to tight and that Is why it broke. Yes thats why it broke. It wasnt aligned right or a extra cam shim was installed or top of head could have been warped. If head is warped you got to ck the top also. If cam dont go straight in and you cant turn it by hand STOP!!!!!!!! fix this. if you can turn it somewhat by hand then its probaply ok and it will wear in. A perfect cam alighnment is when you can turn with just the fingers. I cant believe there is a .050 different in cam size at the lobe as most list .390 lobe lift or .412 . I know the Nissan motorsport book say the SSS is .430 or so. But others book say the l20 is same as the SSS which most list as .412 depnding on year. I was go got mention to ck the cam. But rarely if I ever seen one break beside the one with the photo above. Most times a lash pad fallsout or needs valve adjustment when loosing a cylinder. I would just bolt another head on. as finding the so called correct cam and using the old rockers on another USED cam is another NO-NO Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 I used calipers to check to lobes. Car seems to run ok I guess I'll look for a head. Hope this will last till I get the cash Link to comment
banzai510(hainz) Posted June 8, 2011 Report Share Posted June 8, 2011 could have been a mild regrind cam. I have ones of those in a FREE L20 I got also. Bu its still not per spec. Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 Well like I said i had a 210 head rebuilt for l16 that's what cam came off of. When I put towers from that l16 the cam slid right in on l20. Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 I try and take Very good care of my car I wish it would really like it to stay running for more then a month. Link to comment
nismo dr Posted June 8, 2011 Report Share Posted June 8, 2011 lol most destroyed one Iv seen so far :lol: VVV It still ran on #1!!!! Link to comment
banzai510(hainz) Posted June 8, 2011 Report Share Posted June 8, 2011 I put new cam in old towers and I could not spin it with even with out litters then you say; When I put towers from that l16 the cam slid right in on l20. So Iam confused. its only 13pounds to torq tower down and make sure it spins I have extra cams if ytou closer I give to you but I think they L18 Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 I have 2 motors l20 that is in car and l16 with new head that's out of car. Pulled cam from 16 put it would not go in and spin. So I pulled towers from same head I got cam from and now the car runs Link to comment
Jersey Posted June 8, 2011 Report Share Posted June 8, 2011 I believe that the cam towers are exclusive to the head they originally came on. I believe they are align(?)bored while installed on the head. So if you took towers off one head and then installed on another and found the cam binding(not turning)this would make sense. As for a cam breaking, that happened to me, it broke right after cylinder #3 and I was fortunate enough to make it home(25 miles) on 3 cylinders! Jersey Link to comment
Skib Posted June 8, 2011 Report Share Posted June 8, 2011 I believe that the cam towers are exclusive to the head they originally came on. I believe they are align(?)bored while installed on the head. So if you took towers off one head and then installed on another and found the cam binding(not turning)this would make sense. As for a cam breaking, that happened to me, it broke right after cylinder #3 and I was fortunate enough to make it home(25 miles) on 3 cylinders! Jersey the cam towers are aligned to each other. they are not exclusive to the head. Iv swapped whole cam tower/cam/rockers/ect sets over to different heads and never had a single problem. if you start mixing and matching towers tho, you may run into trouble Link to comment
ricky Posted June 8, 2011 Author Report Share Posted June 8, 2011 No I swapped all towers that were board for the cam they are just off l16 but I did not change rockers or anything else. Link to comment
ricky Posted June 9, 2011 Author Report Share Posted June 9, 2011 The cam no longer binds. The only issue is now is that I can't get .011 valve lash on some cylinders so I'm getting detnation while valves are open. No mater what the timing so at idle you can here popinng out of exaust Link to comment
datsunaholic Posted June 9, 2011 Report Share Posted June 9, 2011 If you got it to spin freely with the replacement towers then I think you're fine. The head probably isn't warped, since they wouldn't have aligned if it had. Probably had one tower out of alignment originally which overheated then snapped the camshaft. However... If you can't get .011 on any valve that's not good. Too tight or too loose? I'd have to think too tight, which is indicative of a badly recessed valve (seat or valve overground or just burned out). I've heard of folks milling a little off the valve stem to solve that, otherwise you need a new seat or valve, or a thinner lash pad. Of course that's assuming you didn't try adjusting with the valve open or partially open... and yes, I've seen some folks try it. Link to comment
ricky Posted June 9, 2011 Author Report Share Posted June 9, 2011 I think it's because the lobes are significantly bigger the broken one. I think I will find a head to get built for motor and swap whole thing with a new cam Link to comment
Chris#51EPGraham Posted June 9, 2011 Report Share Posted June 9, 2011 Interesting discussion. One reason they can lock up like that is because the aluminum castings gradually distort the heck out of themselves over millions of heat cycles. The gasket surface is typically warped .004 - .006 on a high mileage head that HAS NOT been overheated. Result is that original machine work is no longer close to where it started 40 years ago. Sometimes loosening, tapping with a mallet and retorqueing will get them aligned. Milling the head top surface and tower bottoms will solve the problem if done correctly and the head is being totally redone (lot of work...the towers need to be fixtured somehow on a straight cam...0r a machined bar precisely the same diameter as the cam journals). Link to comment
Jersey Posted June 10, 2011 Report Share Posted June 10, 2011 the cam towers are aligned to each other. they are not exclusive to the head. Iv swapped whole cam tower/cam/rockers/ect sets over to different heads and never had a single problem. if you start mixing and matching towers tho, you may run into trouble Skib thank you for educating me on this, I've actually passed on a few heads that were missing the towers but, otherwise were in great condition! Jersey Link to comment
krecs Posted June 11, 2011 Report Share Posted June 11, 2011 Hey guys I need a cam I'm in Sacramento call or text or pm 916-690-5587. Need asap hey i have every thing except the head is crack let me know if you need it thanks Link to comment
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