Team Camaro Tech banner
1 - 11 of 11 Posts

·
Registered
Joined
·
26 Posts
Discussion Starter · #1 ·
Today I was installing 1.5 roller rockers on my 355. I've never done this before, and I've never adjusted valves ever before either. Anyways I was reading an article in Chevy High Performance about installing them. First they said to snug the rockers down so I snugged the rockers down. However I misunderstood their term of "snugging down". Instead of just snugging the rocker against the pushrod, I snugged the rocker all the way down the stud until the bottom of the rocker was touching the head. I didn't know this until I took it apart and thought about what I had done. I then loosened the rockers up one by one and adjusted them one by one. However when I was using my remote starter to turn the motor over to adjust each one the other ones were still tigntend all the way down the stud. I didn't think about what I was doing and obviously this was really dumb. Anyways I adjusted them all, and started the motor and it started tapping so I shut it off and tried to think about what I could have done, then it dawned on me about the whole snuggin down thing. I then took all the rockers off and pulled the pushrods and 2 are bent pretty bad and 3 other ones have a slight wobble. Does anyone know if I could have wiped off a cam lobe, or possibly cracked the cam, or if I could have done any other damage. The studs aren't pulled out at all I already checked that, but I don't want to start it knowing that I could break something. I know this was a really dumb move but any advice is appreciated.
thanks in advance.
 

·
Gold Lifetime Member
Joined
·
8,747 Posts
Although you may damage the cam with what happened, I'd bet it's fine. However you need to remove all the pushrods and check for straightness; rolling them on a flat piece of glass works well. Replace all of them or at least the bent ones and adjust the valves as follows from the Crane Cams website:
http://www.cranecams.com/hydlfaq.htm

Jody

------------------
MY CAMARO
 

·
Registered
Joined
·
2,372 Posts
The pushrods are bent because of mechanical interfearance. The cam lobe was pushing but the rest of the valvetrain was unable to move so something HAS to give, and in this case it was the pushrods. If you think about it, there is a possibility that the valves were hitting the pistons. If that happened, you will need to do a lot more than just replace a few bent pushrods. The valves can become bent from contact with the pistons. If that happened, you need to break out the toolbox and pull off the heads and have them checked out. Sorry


-Mark.
 

·
Registered
Joined
·
4,386 Posts
You can do a compresion check to see if you bent any valves. After you put the rockers on. This would be a good safety check before you try to start engine. If a valve was bent bad it could break & destroy the head & piston.
 

·
Registered
Joined
·
62 Posts
I once worked at a filing station that did uneducated auto repair. One day we had a college sophomore come in with his 73 Camaro. Our "crack mechanic" deduced a timing gear problem. After changing the timing gear, he decided that there was slack in the valve train and proceeded to tighten every valve as much as he could. He then tried to start the engine and was amazed the 350 wouldn't even crank.
The end result? An engine overhaul with complete head work and one less college student around SIUE because he had to go back home to Chicago to pay for his car repair.
If I were you, I'd have a reputable repair shop look at the engine and check every thing out, then make your necessary repairs. It will be costly but you'll know everything is right.
 

·
Registered
Joined
·
80 Posts
To be honest with you, I did the same thing to my 305 sbc 1 year ago. I was just tinkering with the engine to see how things worked etc. Anyhow lucky for me the engine was 25 years old, and I had a new one on the way. I traded the thing in at a local parts store for a new one (core exchange). I later read up on a manual by David Vizard on how to adjust the tappets on a hydraulic cammed engine. Anyhow good luck hopefully nothing was damaged, I just thought Id tell you that you are not alone, I traveled the same road. Funny thing I did turn over the engine with all the rocker nuts cranked down, I will never forget the big huge backfire I heard, to top it off i was in my garage. Believe me Ill never forget know how to set the tappets.
 

·
Moderator
Joined
·
10,164 Posts
Just a suggestion, buy a good factory manual for your car and follow it exactly.
It would be a great thing if you found a talented guy who is doing the kinds of things you want to do and watch how he does it.
David

------------------
Check my web page for First Gen Camaro suspension info:
David's Motorsports page
First Gen Suspension Page
67 RS 327 original owner. 69 Camaro Vintage Racer, 65 Lola T-70 Chev SB Can-Am Vintage Racer
 

·
Registered
Joined
·
467 Posts
Just replace all the pushrods, adjust the valves (use a good manual indeed), and check the compresion on all the cilinders, i'll bet you will be fine. You can buy a compression tester and test it yourself, they are not that expensive and you'll have another cool tool....

(note: the indication on the tester will not be very important, what you are looking for is one or more that are completely off with the rest)
 

·
Registered
Joined
·
5,277 Posts
Another thing to be aware of is spreading of the roller tips. Depending on the design of the rollers, if you really mash things down, the casting will spread apart where the roller rides. As a result, the pins the rollers ride will walk out of the roller. If found this out on my motor which I bought from someone that may have done the same thing you did. Fortunately, crane offered to replace the roller rockers free of charge.

-dnult
 

·
Registered
Joined
·
873 Posts
A friend of mine adjusted a solid lifter cam like it was a hydraulic cam. When he started the engine it broke 2 valve springs. What you did, put a lot more pressure on the springs than his mistake. Id at least take the heads off and look at the pistons to see if any have valve damage and then have a good shop inspect the heads to see just how much damage was done.
---------------------------------------------
68SS 396/375 L-78
 

·
Registered
Joined
·
925 Posts
If you are really worried about piston to valve contact, like everyone else said, get a compression check tool, go from each cylinder and check they should all read pretty close, maybe 2-5 psi, if one or two is way off, then you know you bent a valve, this is really easy, all it involves is taking out sparkplugs and screwing in the compression tool. I had to do this when my timing belt broke on my honda, everyone told me i probably bent a valve, but i checked and compression was good on each cylinder, so i ran it after puttin on a new belt and it was fine, buy a set of pushrods adjust the valves, and check the compression, you are probably fine, let us know

------------------
http://www.geocities.com/codybouc/firebirdpage.html
 
1 - 11 of 11 Posts
Top