kakapoopie Posted July 31, 2009 Share Posted July 31, 2009 I got my 71 240Z started for the first time today. It idled around 1000 rpm (very rough) and the engine was shaking kind of bad, and a loud ticking noise coming from under the valve cover. I took it off to investigate, and this is what I found. The rocker guide (lash pad?) was sitting on the floor of the head and looks to be fully intact. The valve spring retainer on the other hand was mashed up a bit and is a little tight for the rocker guide (lash pad) to fit into. If I want to get the retainer off, I'll have to take off the camshaft and rockers, because I only have one of those universal valve spring compressors that gets blocked by the camshaft. My question is, are there any ways around having to pull off the camshaft to get this issue sorted out? (grinding part of the rocker guide (lash pad) to make it fit?) Quote Link to comment Share on other sites More sharing options...
DrSideways Posted July 31, 2009 Share Posted July 31, 2009 Not too good for start up. What kind of guides do you have. Looks like the valve may have stuck in the guide and knocked the rocker off. Did you do a proper cam/rocker pattern wipe during assembly? From here stop and figure out these two questions and go from there. If you did not do a wipe pattern then stop and learn how to do one. (not picking on you, just one of those things) If you have cast iron guides then they weren't reamed out enough. The iron guides can be used, but need to have good clearance. If you have bronze guides then that "should" not be the problem. You may install the rocker and turn over and do a leak down checking for damage. Do not just put the rocker on and restart. Keep us posted, Alan Quote Link to comment Share on other sites More sharing options...
kakapoopie Posted July 31, 2009 Author Share Posted July 31, 2009 Dr Sideways - I don't know if a cam/rocker pattern wipe was done because I didn't build this motor. It had supposedly been sitting for two years, and I just finished replacing the fuel tank, hoses, filter pump etc. Also it is a 240z e88 head with 280z n24 block I'm not sure if I used the correct term for the part I'm talking about. It's the little circular thing that goes ontop of the valve spring retainer and has a groove for the rocker to slide on. I put a magnet to it and it is iron. I'm not sure if it's clear in the picture, but the seat for the rocker guide is slightly smashed in from one side (from being hit by the rocker I assume) Either I'm misunderstanding your answers or I've named the parts wrong. I'm probably being dumb haha, thanks for the help so far. Quote Link to comment Share on other sites More sharing options...
DrSideways Posted July 31, 2009 Share Posted July 31, 2009 Dr Sideways - I don't know if a cam/rocker pattern wipe was done because I didn't build this motor. It had supposedly been sitting for two years, and I just finished replacing the fuel tank, hoses, filter pump etc. Also it is a 240z e88 head with 280z n24 block I'm not sure if I used the correct term for the part I'm talking about. It's the little circular thing that goes ontop of the valve spring retainer and has a groove for the rocker to slide on. I put a magnet to it and it is iron. I'm not sure if it's clear in the picture, but the seat for the rocker guide is slightly smashed in from one side (from being hit by the rocker I assume) Either I'm misunderstanding your answers or I've named the parts wrong. I'm probably being dumb haha, thanks for the help so far. No matter about not checking the wipe now. However you might want to double check prior work as it is real $$ when it does not work. The "circular" thing is the lash pad. They come in varying thicknesses to adjust the wipe pattern. They will be ferrous. The part that is buggered up is the top of the retainer. If it was me I would replace that. The guide I am taking about is what is pressed into the cylinder head for the valve to slide up and down in. Tight iron can seize the valve and hold it open for the piston to hit. It can also hold it open ( down in the head) so the lash pad has room to come off. So in the end may cause damage to the piston, retainer, rocker, and lash pad. Now you know why it is important to know what cam wipe is as well as the materials used. I guess it could be worse.... somehow. Having it happen in the shop is better than on track or a long way from home. Make the diagnostic checks and keep us posted, Alan Quote Link to comment Share on other sites More sharing options...
kakapoopie Posted July 31, 2009 Author Share Posted July 31, 2009 Well, I guess tomorrow the camshaft is coming out . Arghh Quote Link to comment Share on other sites More sharing options...
sticky280zx Posted July 31, 2009 Share Posted July 31, 2009 no need bud, just get a buddy and a big screwdriver/prybar.....have your buddy push STRAIGHT down on the spring....it will compress....then put the retainer back in and retainer on....this just happened to me and i have no clue why but it did and i adjusted the valves and kept the two that did that / / / a little tighter and havent had any problems yet but NO NEED to take all of that out Quote Link to comment Share on other sites More sharing options...
kakapoopie Posted July 31, 2009 Author Share Posted July 31, 2009 sticky- I'm trying to get the spring cap (valve spring retainer?) off too, which I shouldn't do with a screwdriver, no? Quote Link to comment Share on other sites More sharing options...
kakapoopie Posted July 31, 2009 Author Share Posted July 31, 2009 well I ended up just tapping the lash pad into the cap with a hammer. it didn't take much to get it in, and once it was in, it swiveled freely, so I figure it should be ok for now. I put the valve cover back on and started the car, the shaking seems to have gone away for the most part. but the tapping noise is still there. i listened to the valve cover with a screwdriver and it sounded normal. it really sounds like it's coming from the carburetor area, i couldn't pinpoint the noise with there either. I'll try to post a video later. Quote Link to comment Share on other sites More sharing options...
kakapoopie Posted July 31, 2009 Author Share Posted July 31, 2009 Here's a of what it sounds like after putting the lash pad and rocker back on. (no muffler) I'm gonna check and adjust the valves now, do you guys hear any obvious issues with the idling? Quote Link to comment Share on other sites More sharing options...
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