Ok, so my O/T daily driver got totaled, so the money went into making my next closest ride ridable. Here is what I have got. 1953 ford f100. 351w fmx out of a 71 torino. The motor was built my the machine shop, my mechanic friend and myself about 5K miles ago. My friend was in charge of specs, to which he bought a 268/512 lift cam and a few other little things about the truck made it too dangerous to drive, so I parked it for a few years. So here is the thing. I bought an edelbrock performer cam to match the intake and carb. I installed it about a hundred miles ago, however when the heads were at the machine shop, the guy instead of changing the seats in the heads, he put oversized valves in it. 2.02 what I was told, and heavier springs. Now when I put the new cam in, I put new lifters and new timing set. I started it up and it ran real smooth for a short time, and pulled 17hg on the vacuum gauge. After a while it started to get alittle less smooth and act kind of fluttery under a load. I also notice a ticking sound like the lifters are collapsing. Im running 15w-40 and I also notice that when its colder and I first start it, it seems to be better than when it gets warmed up and have been driven a few miles. It gets worse as it gets warmer. So here is the question. I have new springs (NOW) that are supposed to be matched to the cam and new pushrods. I have a feeling that I am going to have to replace the lifters too because of the ticking, but I am wondering if all of this is because I didnt change the springs, or if I change the springs will it straighten out, or were they just bad lifters to start with? Anyway, I plan on changing the springs and pushrods and see what happens, but deep down I think I will have to swap out lifters too because of the ticking and fluttering, but I am hoping that changing the springs will settle the rest. Anyone out there that works on engines for a living have any experienced input on the subject please chime in with words of advice and explanation to go with guidance. thanks.
X2 on the break in question. I assuming the lifters are hydraulic? Don't tear anything apart until you have identified the source of the noise. I would try to identify which side the ticking is coming from and pull that valve cover to see if you have excessive lash or anything looks hinky in there. That should be a "pedestal" valvetrain, so no excuse for the valves coming out of adjustment.
You guys are reading my mind, wiped cam lobe(s). How did you break it in? A flat tappet (non roller cam) motor needs to be brought immediately up to about 2000 rpms and kept there for at least 20 minutes. They also need an oil with the highest zinc load you can find and a zinc additive for sure. These days lobes get wiped sometimes even if you do everything right. The springs won't make the difference you are seeing. Pull the valve covers and watch each rocker to see if they all go up and down the same amount. It is possible something else is going on,but a wiped lobe is a good place to start looking. Don
Since you are talking about changing lifters, I assume you didn't buy lifters with the camshaft. I always buy lifters from the cam manufacturer so the metal alloys are matched. Different manufacturers have different alloys that might not match up well and cause wear. I'd be checking lobe lift to see if one is worn.
If the springs put higher than stock pressure on the lifters, it could cause lobe wear. Checking lift with a dial indicator isn't too difficult.
Ok, so. Yeah I bought the lifters and cam as a set. Yes, I did a 2k/ 20 min break in, however during that time is when things started to change. It was then that I read that for warrantee items, the matching springs needed to be installed at the same time. And even now when its cold outside I can get a smooth idle at start up, and then about ten minutes later it flutters on acceleration. Sounds like I need to start over with a new cam set. it seems like its coming from the passenger side, third one back. I will get up courage to do a compression test tomorrow. I wish I had a dial indicator. One of the tools I dont have. I did the initial timing with a light bulb and alligator clips, if that tells you what my tools list looks like. Keeps the help coming, thanks. I will see what tomorrow brings...
Oh, one funny (now) side note. I pulled the plug wires from the passenger side to take the rocker cover off, and after getting frustrated and distracted, I fired the truck up, after buttoning it up, only I forgot to put the plug wires back on, and it fired right up and even idled better, only to discover the horror of having the plug wires unattached on the entire side that was now rubbing on the alternator belt! I shut it down and although a little damage to one wire, the truck ran pretty good on four cylinders. Anyway, thought I would share that one.
What rate oil did you use? If it was SM or SN you don't have enough zddp. If it is SF, SH (pre SM) you should have been OK.
You don't need a dial indicator... Just pull the valve covers and take ALL the spark plugs out. Motor it through on the starter or (better yet) turn by hand with a breaker bar. If the cam is wiped that bad you will be able to SEE the valve(s) that aren't moving. One thought on the cold start... If you have a damaged lifter, it might work a little better until the oil gets hot and thins out. Doesn't make sense that it's the only problem though...
The guys here have given you good info. I would like to add one thing to the break-in process. If those springs you used have substantial pressure, than you've probably wiped the cam. I always break cams in with 2000 rpm, verying the rpm from time to time, with the proper oil or additive but I always use an old worn out stock set of springs and change them after break-in.
get an engineered set: cam, lifters, springs, etc. call a cam grinders tech line and get the advantage of their expertise.
Before throwing another cam at it, install the springs and see if it helps. Make sure that it is lifter noise not an exhaust leak. Harbor Freight has a stethoscope for about $5, a dial indicator for $12 and a magnetic base for $10.
Thanks again everyone. Tomorrows schedule will be to do a compression check, buy an instigator with a magnet, and will report findings. I have to laugh at the stethoscope though, I have a son that has Downsyndrome who loves to role play. I used to have a stethoscope until he wanted it and I had to remove the dangerous part from it. I now use a screw-in antenna as my scope since I have no radio. OK, so we will see and I will report back.
OK, so todays events are as follows- I went out to do a compression check. I got 50 on cylinder 1 and the rest were all 145. So I go back to 1 and do it again, now its 45. So I pulled the rocker cover and bumped the motor and the springs went up and down. I rediscovered my micrometer so I measured the springs and they were almost equal height( .10), but when they were down, the intake was different even more. This is when I noticed that the pushrod was real tight and there was a weird nut on the stud. All the other ones were 9/16, and this intake nut was 1/2 and had a flattened out lock washer under it. What? So I stick the compression gauge back in and loosen the nut. take a four rotation reading 150 lbs! I was so relieved, but I'm still trying to figure out what the difference is and how long the nut is going to stay in position. I took the lock washer out, and I took the rocker off and examined the stud for damage and wear. It hasn't pulled out and its identical to the stud next to it. Now I am wondering if the ball and nut need to be replaced? Anyone want to chime in again please?
Ok, so I feel like I'm talking to myself. Maybe I am. Anyway, so I bought the last known rocker "kit" known to the napa world in the eastern U.S. but I am still at a loss for why a different nut, would hold the intake valve open. Any sugestions? admittedly, I didn't check the pushrod length, and will be replacing it anyway, but its puzzling to me why.
I can't remember for sure, but the nuts may be locking nuts and the clown lost one, put a lock washer under it to keep it from backing off. The early engines may have been adjustable, tighten the nut until it stops ticking and put another half turn on it. The later studs had a shoulder on them and you tightened it down till it stopped. I am pretty sure the studs will be pressed into the head and not threaded. If the studs do not have a shoulder where the threads stop, you can adj each lifter for proper preload. With the engine warmed up pull one valve cover, throw a heavy rag over all the rockers except the one you are adjusting. Back the nut up until the lifter clacks, retighten until it stops, then put 1/4 to 1/2 turn more, go to next rocker. If the studs have a shoulder and you want to run it not bottomed out, you can use a jam nut to hold it in place, but the smaller threaded section above the shoulder is a little small for stout springs or high revs.
its not adjustable. I believe that in order to change an adjustment, I would have to change pushrod length.
The stud nut backed off? Strange, you normally just tighten it up & your good to go. Perhaps someone over torked the nut & messed up the threads @ the bottom of the stud & used the washer as a spacer to get to usable threads, if so you may need to put in a new stud.
If all he did was lose the shouldered nut, get a replacement from junkyard or Dealer( Dealer only new?).
Take all of the rockers off and place a straight edge across the valve tips. I think you will find your problem >>>>.
I will certainly do that. I recognize your expert opinion from other threads. I still wonder why the valve was being held open, unless not only the wrong nut was on there, but the push rod is too long as well? Or maybe the oversized valve is the wrong length.? Anyway, when it stops raining and isn't close to freezing, I will get the straight edge out and do some more measuring. Thank you everyone so far. Amazingly, the truck has been getting me back and forth to work and is running smoother. The new nut will be in hand friday.
I think you will find your issue is the 2.02 valves. The largest valve installed with stock piston reliefs was the 1.78. Piston to valve clearence will cause the issue you speak of. Be there done that.
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