HDIronman

The 69 has been running exceptionally well lately, until today.

see pics



another view



About 3 miles from my house I started to hear a slight ticking, it was quite distinct from my header gasket leak. Yeah I gotta fix that soon. Then it got worse, I heard a little snap, and I shut it down immediately. It all happened in a matter of about 15 seconds. I pulled the valve cover on the spot, and could not beleive my eyes. The rockers are PROFORM, purchased locally, with only about 500 miles on them. The valve was adjustedly properly, without a doubt, no question. So I figure it was a bad rocker from the manufacturer. They must have started wearing through as soon as I installed them.

Anyone else ever experience this, or hear of it...?

I haven't taken anything apart yet, so I dont know if anything else is wrong. But all looks to be okay at first glance. The end of the pushrod that came through the rocker apears to be undamaged. Can't wait to see the other end. Probably need to get a look at the lifter also.

Will update...

UPDATE 10.14.04

Today I spoke with Dennis at PRO-FORM PARTS, he is going to give me a full credit toward a new set of full roller rockers. We'll see if these last any longer.

GrandSportC3

Time to upgrade to aluminum roller rockers...

HDIronman

I've actually started collecting parts for a complete new 383 build this winter. This engine will then become a spare.

Twin_Turbo

instead of aluminium ones, get some steel ones instead, http://www.enginekits.com have stainless steel rockers that look like exact copies of the crower ones, only for much less.

81 Vette

Id say go with alumimun, you simply CANT go wrong that way.

Harland Sharp 1.6:1 aluminum roller rockers are good enough for guys like scott shafiroff and bill mitchell, they should work for you...plus they arent stupidly expensive, less than crowler.

Twin_Turbo

Fatigue life of aluminium is much less than that of steel, not a problem on a race car but if you intend to drive some serious miles... not to mention that the stainless ones, unlike the alu ones, are rebuildable.

Look at the price of these crower copies, then decide what is a better deal, those or the aluminium ones.

Lotus76

Phillip
Really sorry to hear about this. I was hoping you kept the vert in good shape till you decided to sell it to me.

I think you stressed that poor old motor way to hard trying to hang with that RED STINGRAY last weekend on your trip to Hell

Yep I think you should pull that engine right away and just to get even you should take it to that guys house and drop it off in his garage...

(On a stand in the corner would be fine)

Then you can begin to put together that mean stroker while the weathers still hot outside

Let me know if the old tired worn out engine needs a new home, you know you could use the space and the money can go right into the stroker...

Your cruise partner,
John

HDIronman

Okay guys, about the rockers, I'm gonna replace them all cause I can't trust them now. But I will most likely put the stock 1.5 rockers on for now. It's the end of the driving season here and I intend to build another engine this winter anyway. I already have the rotating assy. and a block lined up for the build.

What I really would like is opinions on the failure I had today. Has anyone seen this before, and what could cause it...???

The pushrod was bent only where it went thru the rocker. I think that was a result and not a cause.

phillip

stingr69

I have seen stamped steel rockers punch out the pushrod cup before. It was a 327 with a lot of miles that I put a bigger cam in. The pushrod cup had worn to the lift of the old cam and was now on fresh metal with the added lift. Punched it out quickly. Replaced the pushrod and rocker and all was well after that.

Pro-form is strictly the lowest shelf when it comes to duabillity. I ran a set of Pro-Form stock replacement style and the wearing surface near the valve stem was trash on a few of them in a short while. The heat treatment is very poor for long term use. "Claimer" parts is what I would describe them as.

Comp cast steel roller tips are a very durable replacement. I use them on everything now. 1.52 ratio or 1.6 if that floats your boat. Crane sells a Nitro-Carb coated stock replacement style that is excelent but the Comp roller tips are great and do not break the bank. Either way get some new pushrods if you have any miles on them or if they are suspect. Lifters should be fine.

-Mark.

MILO

Is it possible this was caused by the push rod being clogged and not being able to lubricate the rocker arm? Did a lifter become clogged? Rocker arm was out of adjustment? Just a rocker arm defect?

Fevre

ARG! That blows Phil but could have been worse.

comp

had a buddy do that to ONE out of the 16 put a new rocker and puch-rod in and Zero problems after???? may be a few bad get thew QC

bracketshark

Any one considering new rockers should check out this website:
www.mid-lift.com/PVS-PS.htm
Read these articals several times, (inroduction, midlift, technical) It makes sence not to us a cheap set of rockers. They can be bought on E-BAY for 188$ per set for a small block a little higher for big blocks. These are trick and will last a very long time and have less wear on the valve train, due to geometry improvements. Alot of very interesting info here. Oh yea, I'm new and will need info on frame off restoration of my 71 coupe later.

maluminse

Same thing happened to me one time. A leaky header gasket was masking a poorly adjusted valve. Pushrod punched through the rocker arm and pinned an intake valve open. I replaced the pushrod and rocker arm with parts store stuff, and I have never had a problem since. Maybe I was just lucky.

HDIronman

The engine, the rockers, and the pushrods have less than 500 miles.

Larry B.

I relly can't believe that someone actually make stailess steel rockers! Stainless is terrible for moving parts. I galls very easily. While it has good surface strength it is not a good choice for rockers.

GrandSportC3

71coupe

Happened to me before with standard stamped rockers. They didn't break thru, but several had cracks & chunks missing. Turns out the lifters I installed with the solid cam were designed to limit the oil flow to the top end & full roller rockers were required.

HDIronman

UPDATE 10.14.04

Today I spoke with Dennis at PRO-FORM PARTS, he is going to give me a full credit toward a new set of full roller rockers. We'll see if these last any longer. [/QUOTE]

Scooter70

Hey John,
You have to give me some time to strip the rotating assembly out of my old block so Phil can come pick it up and drop it off at his machinist's shop. I'm not going to be able to get into it until next week sometime.

-Matt