Ken -

Thanks for the info. I'll check the tips.

Chris -

Thanks for the additional thoughts. I am going to reuse the cam. It is a mild isky I am rather attached to. I am planning on just change the lifters. The machine shop is working on the head and have not finished yet. Exact reason for failure, unknown at this point. Machinist initial survey concluded the other springs were ok to reuse. He thinks it is a heat issue. The work will be completed tomorrow and I'm sure he will have a better idea by then.

One additional issue I have yet to resolve is that the piston below the seized valve has two light cresent moon marks on the top where it contacted the piston. Hmmm.... I am going to dye penetrant the piston top to check for cracks. By the naked eye it looks ok, but the dye check should tell the tale. If it is cracked, the gig is up for this engine. I'll swallow my losses on it and go for a new unit.

Good thing my wife is so understanding. She says it keeps me out of trouble.


Bret

I did make the recommendation based on him having the heads off and not replacing the cam.

When you have a set of valve springs some are stonger and some are weaker. this happens when a car has sat for a while with the vavle train in one position a couple of vavles springs may be weaker than the others or its natural for springs to wear differently over time.

this will lead to some of the hydrauic lifters centering at different locations also. with a new set of lifters and old springs they will often recenter to the exact spot the old did and can lead to engine being slightly out of balance.

but I have also had experiences where i replaced lifters and destroyed cam lobes, ive replaced lifters and then had pushrods bend.

also at the very least while you have the heads off it never hurts to check the valve springs for proper tension. the man I bought my car from rebuilt the engine only about 500 miles before I bought it. however it sat for well over a year. I checked my spring tension and they were way out of spec.

anytime you let an engine sit for long periods of time you should back off the rockers, he did not.

I may just be super cautious but the way i look at it, if you have the heads off might as well fix the heads up right. It may cost some extra money, but it will save you time later and time is money.

with solid lifters id feel ok just replacing the lifters but with hydraulic I generally replaces the springs as well.

remember also spring replacement doesnt require pulling the heads..

Thanks Ben -

You hit on a good point. This engine had been sitting on the sidelines for a over a year while another engine got some duty. It was put back when I got the car. The rocker arms had not been backed off. Changing the springs isnt that much more and I dislike doing things twice. Thanks.

Bret

Bret

If the piston is cracked, don't give up on it so easily. With the heads already off, it's not that difficult to pull the oil pan and remove and replace the piston. It will be a lot less costly. Even if you replace all the rings and bearings while you are there, you save money and have a very good engine. It's not a complete rebuild, but it's close.

Thanks Ken.

Piston is ok. Got the head back today. Heat was NOT the issue. The "doctor's" best guess = Broken spring - kisses piston - binds in head. Thats it. Machine shop replaced the broken stud with a screw in type, resized the one valve guide, replaced the one valve, spring, and retainer, and lapped all the valves. Checked all guides and replaced all seals. I went ahead and purchased a complete lifter set (and assembly lube) as well. All thats left is putting it back together. While it might not be the most complete fix, it should buy me some time to save for.......the next engine .

A big thank you to each of you posting your thoughts and suggestions. I feel your help, helped me make a well informed decision. You guys are great.

Bret

hey it reminded me to go back off my rockers from my own engine since its been sitting for 8 weeks with no ETA in sight

|UPDATED|11/23/2004 10:49:47 PM (AZT)|/UPDATED|

What a lucky Guy!!

Bret you are very lucky and I am glad that you found nothing else major in your way. About 14 years ago after I bought my first Vette I saw too much blue smoke shortly after driving it 200 or 300 miles. It turned out that I lost most compression in my #6 cylinder. The cause was the piston had cracked the glans (SP?) which is the area between the rings. I found broken metal in the cylinder after removing the head. I was then able to replace the piston without removing the engine. It wasn't really much trouble, I just pulled the oil pan and unbolted the rod from below. A piston was easily procurred and installation was a breeze.
Whatever problem you find can always be rectified with a bit of elbow grease and a loving wife at your side to tap the piston down the cylinder while you wait below to line it up.
One trick I was going to mention earlier but forgot was when you are putting the engine back togather and need to adjust the valves it always gets real messy and I have had little luck with the clips made to attach to the rocker arms to keep the oil from going everywhere. I took an old valve cover that I bought at Corvettes at Carlisle and then I took a drill and made a hole which then allowed me to use a sabre saw to cut out the center section. This way when I adjust my hydraulic lifters I simply bolt on the modified cover and start up the engine. This way my driveway looks nice and clean and the oil stays where the oil belongs.

By the way, I tought it was interesting about this concept that has been mentioned about loosening your valves when the engine is not being used for a period of time. It sounds like they are concerned about springs losing their tension. This is totally new to me and I question whether it is fact or fiction. My engine and heads were built and set up by a Winston Cup engine builder and the engine was built very carefully and precisely. The valve springs were all within tolerances after the engine sitting for over 30 months. I had driven the car for almost three years and then I put it in my garage up on stands for the 30 month period. After letting it set I was curious so I tore the engine down for an inspection and when we checked the tesion of the valve springs out loose and in place on the head. They were all almost identical to what they were like 6000 miles before. I even used the same shims under the respective valves.
The heads were removed (and rebuilt) while I was inspecting my pistons. I was concerned since I had seen some marks on my pistons using a boroscope and it appeared that my piston to valve clearance was in question. I am running 12.25 to 1 compression ratio in a 427 engine built using L-88 specs. I was happy to find that I wasted a bunch of time in my case.
It is always scarry to have to go inside of an engine but with its always better to be sure.

It sounds like you are doing the right repairs, I wish you all the best and hope that your engine is purring once again soon.

Regards,

Chris McCloskey



P.S. The only bad part of the above story was when my Corvette friends saw the valve cover I used they came after me and wanted to know why I did what I did to that particular valve cover....turned out it was an original 1966 factory cover..hey I didn't know

ctmccloskey said: I took an old valve cover that I bought at Corvettes at Carlisle and then I took a drill and made a hole which then allowed me to use a sabre saw to cut out the center section. This way when I adjust my hydraulic lifters I simply bolt on the modified cover and start up the engine. This way my driveway looks nice and clean and the oil stays where the oil belongs.

this is the method I use also..

Hey Cris -

Great story. I do have the original valve covers sitting in the attic. You know, I think I now have a plan for one of them. It is a good idea. The original valve cover is worth more to me keeping oil where it belongs than sitting where it is.

Ben - If you are doing it also ( cut valve cover) it must be good.

Thanks again to everyone. I'll post once I have everything back together and running. Keep your fingers crossed. I am really ready to put away the wrenches for a while and cruise.

Bret

i wouldnt cut up an orignal set though.. you could give them to someone building a 73 trailer queen..

you should be able to pick one up at a junkyard for peanuts..