[boulonman]

Hi Y'all,

Sorry if I'm posting in the wrong forum, I couldn't seem to find anything about cracked roller rockers. I pulled the valve covers off my newly acquired 68 Chevelle SS clone w/383 stroker to identify my aluminum heads, cuz I bought it through a 3rd party who knew absolutely nothing about the car, hence no specs on the H.P upgrades. I was thrilled to find blue 1.5 scorpion roller rockers, but I noticed 3 of them had cracks mainly at the tip where the pin holds the roller. I know this is a dumb question, but I'm tapped out & can't afford to replace them just yet,

& need the car daily for work. I tried to get the clearest shots possible, but they didn't come out too good, still you can see the cracks fairly well. The car's been running great, & I try not to rev it beyond 4500. Can anybody give me a wild guess as to how long these may last? I am relatively sure they've been this way quite a while, what's the best case scenario versus worst case scenario if I run it a few more weeks till I can install a new set?All opinions are most appreciated, regards A.

 

[ToocoolZ28]

I would not start that car again until I replaced ALL the rockers. Buy stock type pressed steel rockers if you have too. You really don't want those small parts getting loose in the engine.

 

[fasteddies68]

It may be quite a gamble running them with cracks. Could you replace the cracked ones temp. with stock stamped ones until you can afford new rollers?

 

[OLDED]

Call Scorpion and let them know what the problem is without offering the info that you are the second owner. Good chance they will replace all of them at just the cost of shipping. Worth a try. I would replace them with their "Endurance" version.

 

[Tom Mobley]

I'm with Ron.

take the battery out.

 

[Dave427]

Wow!!!

I would be looking for any pieces before it does some really big damage, little needle bearings will do a number on the oil pump.

Dave

 

[pauls72]

Scorpions have a lifetime waranty give it a try. If the heads have no markings on the outside then they are probably procomps

 

[boulonman]

Call Scorpion and let them know what the problem is without offering the info that you are the second owner. Good chance they will replace all of them at just the cost of shipping. Worth a try. I would replace them with their "Endurance" version.

Thanx Olded,
That's an excellent idea! I wasn't aware they have a lifetime warranty..I will most definitely give that a shot..!
regards, Alan

 

[boulonman]

I'm with Ron.

take the battery out.

Hi Tom,
I agree, the battery has been out since I began my search for my unknown specs. I, and/or the original owner must be quite fortunate. I know for a fact he swapped this 383 from a unknown donor car & never took the valve covers off. Hard to say how long they've been like that..regards, Alan

 

[boulonman]

I would not start that car again until I replaced ALL the rockers. Buy stock type pressed steel rockers if you have too. You really don't want those small parts getting loose in the engine.

Hi Ron, I agree, its quite fortunate they didn't grenade earlier. The thing w/installing another set, be it stock or cheaper versions. Is that they all advertise a ratio of 1.5 3/8ths, my scorpions are stamped 1.500, wouldnt a longer replacement rocker change the valve geometry?
regards, ALan

 

[boulonman]

I would not start that car again until I replaced ALL the rockers. Buy stock type pressed steel rockers if you have too. You really don't want those small parts getting loose in the engine.

T.Y toocool,
I agree its too risky just swapping out the cracked ones for the others cant be too far behind..The thing w/installing OEM stamped rockers is that due to not knowing the cam specs I don't know if I can safely install any rockers that are rated 1.5 1/4. My scorpions are stamped 1.500, so I don't know if installing 1.5 1/4 would effect my valve train geometry or does scorpion simply round it off to 1.5 ratio?
regards, Alan

 

[boulonman]

Scorpions have a lifetime waranty give it a try. If the heads have no markings on the outside then they are probably procomps

Pauls77, thanks, I wasn't aware of scorpion's life-time guarantee, I most definitely give them a try. I was thinking of epoxying some heat resistant mesh on the flow back head holes to trap anyhting before it gets sucked in grenades my entire motor!
regards, ALan

 

[boulonman]

Call Scorpion and let them know what the problem is without offering the info that you are the second owner. Good chance they will replace all of them at just the cost of shipping. Worth a try. I would replace them with their "Endurance" version.

Excellent idea, I didn't know scorpion had a life-time warranty, most definitely worth a try, the only markings I see are they are fully blue anodoized w/a scorpion & 1.5 stamped on them

 

[Steve R]

1.5 is the ratio, 3/8 is the stud size. 1.5 and 1.500 are the same thing.

Steve R

 

[VinceS427bb]

wow, you should buy a lotto ticket.
change those rockers out before running engine again........

 

[boulonman]

I would not start that car again until I replaced ALL the rockers. Buy stock type pressed steel rockers if you have too. You really don't want those small parts getting loose in the engine.

Thanks Ron,
I knew the answer was quite obvious, but you know how it sucks to be broke @ the same time your favorite baby is up on blocks! I got helpful replies about: trying to get scorpion to honor their lifetime warranty & send me a free new set, or at least replacing the cracked ones w/affordable OEM rockers, or even a complete semi-decent set of H.D rollers for under 200$. The thing I am not sure about is that the current blue Scorpion roller-rockers are stamped 1.5 (ratio) & all other brands that are 1.5 are actually listed as 1.5 3/8"(ratio). Do you think Scorpion just rounded off their 1.5 ratio stamping, or is there an actual size difference between scorpion 1.5's & say "Jeg's magnum roller tip rocker arms" which list for around 100$ for complete set & claim slight H.P bump, but best of all, they are superior to ordinary stamped OEM Chevy rockers, however they come in only 2 sizes: 1.5 3/8" & 1.6 3/8". I know how to wrench, but am no engineer. I'm concerned about altering my valve-train geometry. And of course, cannot afford a pro to install them. But installation is straight forward: get each valve properly seated by watching the other exh. or intk. begin to open, thus assuring I am in correct position to set the valve lash w/no slop,but still able to spin push-rods easily by hand, then snug it a 1/4, or 1/2 turn depending on the specs. I'm grateful to have found them before they actually grenaded my entire motor! Which brings up another question/idea: would it be worth the trouble to epoxy a stainless screen over the oil feedback holes to catch any big debris? Or will even the tiniest shrapnel still get sucked down into the main block & cause catastrophic failure? I'm also bummed that I cannot find any stamps or marks indicating what brand of aluminum heads I have, the only thing I could find is a "0" stamp between #1 & #3 cylinder on the inner side of the head, but no other makings anyhere..Strange! I also see that all head fasteners are "ARP" but don't know if that just means a complete ARP fasteners kit w/used for entire motor, or if there's any correlation w/the alumn. heads?? Next step w/be removing the intake to see the port shape, unless I am missing something? I am relatively sure this motor is around 4-5 years old & found the following stamps on the rear deck, but none on the front passenger engine block tab: "K12" & "3970010"..Thanks for your help, I appreciate anything else you might know about my "mystery 383"!!
regards, Alan

 

[VinceS427bb]

you will need to figure out type of lifters you have to adjust the lash.
you don't want the 1.6''x3/8'' rockers.
look at the rockers as you remove them for pieces that fell off [aluminum] chunks.
i don't think any needle bearings are in the tips = only the trunnion areas.
you should remove the intake manifold to inspect the lifters and see if any debris made it to the valley area.
the screens you ask about epoxy in place needs to be installed before building the engine.
it will be easier to adjust the lash with the intake off, that reveals the pushrods to spin.

 

[boulonman]

Hi y'all,
A couple months ago I posted a question about my Scorpion 1.5 roller rockers having cracks around the roller tip that pushes down the spring & if I could take the risk of driving a little longer (very carefully) until I could afford a brand new set. (I didn't want to install OEM stamped non roller rockers.) You all strongly suggested I not run it or risk catastrophic failure which of course is logical. You also mentioned Scorpion has a life long warranty but since I wasnt the original owner I didn't think the would honor their warranty. Since I rely on my ride to go to work, I took the chance and filled out their warranty form, & explained I couldn't find the original packing or sales receipt. To my surprise they sent me a return slip & RTV# with an explanation that I had the racer scorpion models which are the strongest they build and their "Endurance model" was more for daily driving then all out performance. They also explained they upgraded their 1.5 "racer" models and I simply needed to make sure my clearances was OK. I just sent my full set of 16 rockers ((8 are cracked) And was told I will receive a brand new replacement set within a couple of weeks!! I wanted to thank all of you who advised me to try to go for the warranty and didn't laugh at my obvious ignorance of wanting to keep driving my cracked rockers til what would have been sure disaster!
I appreciate everybody on this forum for their willingness to help and guide newbies such as myself rather than amuse themself at my expense! You guys rock!!!! All my best, peace Alan

 

[OLDED]

Really happy for you and the way Scorpion dealt with the situation. I have had great experiences with them too. Ed

 

[Keith Tedford]

If this is their best, I would be going back to stock GM rockers. I've never had one go bad in all my years of driving musclecars. All too many of these aluminum rockers seem to give up the ghost. Harland Sharp Stainless rockers are the only roller rockers I would buy.