I was following my dad to a show today and traveling about 35 MPH when I noticed a noise. Parked at the show and it sat for about 41/2 hours. When I went to leave there was no doubt a motor noise. Drove it home and it didnt seem to get any worse but the noise sounds like lifter area and it may be more then one. It never developed a miss on the way home. Tomorrow I plan on pulling the valve covers off to confirm it. Wish I could be wrong but I'm pretty sure it wont be good. I hate todays cams! i followed break in instructions and used break in oil and it still didnt hold up. Guess it may be time to go to roller cam! Rodney
My '73 454 had a small noise that sounded like a valve tap. I pulled the covers off and noticed that some of the stock rockers looked a little crooked. Plus one of the rockers was a little more brown than the others. Upon closer inspection, I found that the brown rocker was worn through the tip over the valve stem. So I pulled off the intake and noticed that most of the cam lobes were worn and pitted on the high parts. Once the rockers came off, I saw that about half of the rocker studs had been ground into on the sides by the crooked rockers. So now I'm in the process of installing a Comp Cams hydraulic roller cam kit, new studs, and roller rockers.
Ain't life grand?
1973 BB 4-Speed Coupe Project Car
John I know what you mean. I pulled off the right side cover only to find that the exhaust rocker on the #8 cylinder was very loose. Noticed the nut was still turned down and at that moment you know you have issues. I'm going to be in the same boat as you, with a roller cam kit going to be the alternative. The engine builder was here this afternoon and said he would contact the cam company and he thinks they will cover any parts I need to replace. Bad thing is I really dont feel like pulling the motor back out but I guess I have no other options. Good news is I dont have to fight with the factory fan shroud since I went with electric fans. But I think the bad things out weigh the good in this case! Any good suggestions on which company wakes the best roller cam kits? Thanks Rodney
I've always use Comp Cams. But lately, I've been reading that Howards Cams is less expensive. So this time I thought I would do some price shopping and found that the Comp Cam Kit (K11-423-8) ended up being about $20 cheaper than the equivalent from Howards Cams. My Crane roller rockers I bought used off ebay.
Since I've found lots of screwy things left from the previous owner, I decided to check the valve spring installed height and, sure enough, they're all vary by about .070. So I re-shimmed everything to within about .010.
1973 BB 4-Speed Coupe Project Car
well some good news, I started by pulling the rocker arm and push rod out only to find the top of the push rod worn off. Wasnt sure why so I removed the intake and removed the lifter. The bottom looked like new! I felt really good at that point. So I pulled the rocker arm on the intake side and it shows some wear at the top as well. I then pulled the cylinder beside it and they are fine. Pulled the #4 exhaust and intake push rod and they have just a slight wear pattern. So I am going to buy a new set of push rods and change the rockers to the 1.6 ratio. This should give a little more cam lift and I also cant be sure if my problem was the rockers or the push rods. Both were new with the engine build but this way I will feel better. The rods are the .100 longer than stock so not sure I can get them until Tuesday. I'll let you know how I make out. Rodney
I wonder what went wrong to cause the push rod to became worn off? Maybe the lifter isn't sending oil up to the rocker. On my engine, I used a drill to turn an oil pump priming shaft and saw that all the rockers were getting oil except the one that was a little more brown than the others. It was also the rocker that had the worn tip.
1973 BB 4-Speed Coupe Project Car
John, When I put the engine in before starting it I also primed the oil pump until oil was coming out all pushrods. I plan on doing the same thing once I have it back together. Not sure why but with wear on more then one rod I am guessing a bad set of push rods. The are the chrome molly so they shouldnt do that. I might also check for oil at top once I fire it up. Just hate that oil mess clean up! If all goes well I plan on taking it to OC maryland on Thursday. That will be around a 500 mile trip. Rodney
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Rodney, be careful going to the 1.6 ratio. You need to be SURE the valve springs will handle the extra lift without binding. Most can, but you certainly do not want to damage any of that stuff, including the cam/lifters.... I've seen many pushrods, and rocker arms wear thru over the years. Chances are, some parts got thru that were just not hardened properly...it happens. Definitely need to make sure all of the rods are flowing oil while running. Yeah, it makes a mess, but....how much trouble is tearing this thing back down, compared to cleaning a little erl off the engine? A rocker that is adjusted a little tight can also keep it from oiling well. The lifter has to be able to pump up/down slightly... Just throwing idears out there.
I agree with the Comp Cams....always had good luck with any of their products. Lunati is great, too, but sometimes a little $$$....
____________________________________ Joel Adams C3VR Lifetime Member #56 My Link
Picked up the push rods and rockers today. spent the night putting everything back together tonight. Will start it tomorrow night if all goes well. Got to be to late tonight and I have neighbors, so I thought tomorrow will be a better choice. I did prime the oil pump and all rockers are getting oil. I plan on checking the oiling once its running and once warmed up I'll check the springs for clearance. It requires a clearance of .060+ when fully compressed. I'm hoping for about .080 or more. Also will be changing the oil and filter just to be on the safe side. Hoping it all works OK and I can still make the trip to OC this weekend. I'll know more tomorrow and let you know! Rodney
Started the car up last night and everything seems fine. I decided to go over the valves again while the car was running and I checked that each lifter/pushrod was pumping oil. All is good there. I checked the spring clearance and have well over .090. Put all backed together but couldnt drive it because the weather was rainy. Today should be a good day for a drive. Just glad everything worked out but I still have no reason for the pushrod wear in the first place. By the way, the change with all new push rods and going to the 1.6 rockers was at a cost of $284. That includes intake and cover gaskets.
Next step is to pack the car tonight for its trip to OC! Hope all goes well.
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