loose rocker arms

[speedracer]

Hey guys anybody had problems with the bolts getting loose on a SBC 350.  And to top it off it sounds like a squealing noise (fan belt type) coming from there.  Would loose rocker arm bolts make that noise too besides the tapping?  And how do ya solve the problem?
Thanks, johnny

[Dave]

Hey guys anybody had problems with the bolts getting loose on a SBC 350.  And to top it off it sounds like a squealing noise (fan belt type) coming from there.  Would loose rocker arm bolts make that noise too besides the tapping?  And how do ya solve the problem?
Thanks, johnny

I never heard a squealing noise from the valve train my self.. Loose rocker arms? Maybe over revving it and they are now pulling loose from the head? Ive also stuffed a pushrod thru one and pulled the bottom out of one from to much rpm.
Yup ive done it all    
Dave

[Carnut]

Loose rocker arm bolts? Yep. Notice second rocker from right.



Result of loose rocker.



Entire story if curious

[EMSjunkie]

Yup ive done it all    
Dave

Yes he has..........and quite well    

Vance

[Dave]

Yup ive done it all    
Dave

Yes he has..........and quite well    

Vance

Thanks buddy i thought you quit pickin on me :cry:
Dave

[BFS57]

Hello;
I read your post and had to put my 2 cents wort in. I recently had an intake gasket failure. It sounded like I had a blower on my motor! Loud as can be! Had one cylinder that kept fouling plugs! I finally got a clue by spraying WD-40 around where the intake meets the head and noticed a much improved running plus the sound went away.
I'm not saying this is your problem but it sounds like it may be part of your problem! Sorry man, gotta take it apart and give it a concentrated look!

Bruce

[speedracer]

Hello;
I read your post and had to put my 2 cents wort in. I recently had an intake gasket failure. It sounded like I had a blower on my motor! Loud as can be! Had one cylinder that kept fouling plugs! I finally got a clue by spraying WD-40 around where the intake meets the head and noticed a much improved running plus the sound went away.
I'm not saying this is your problem but it sounds like it may be part of your problem! Sorry man, gotta take it apart and give it a concentrated look!

Bruce

Thanks Bruce I was thinking the same things, but I will spray the w-d40 before I do anything drastic.  I did run the motor hot a couple of times (like about 215 degress) and noticed the chrome intake schorched in a couple of places.  I really thought I might have cracked the aluminum heads but I dodged a bullet on that one.  I've always had a problem with the rocker arms backing off, wonder if thats the norm with SBC's----------------------------johnny

[BFS57]

Hello Again;
Did you build the motor in question? I am not a builder, but I have seen enough to know that some guys use either contact cement or thread locker on some things when building a motor.
The recent (last year) motor I just put in my '57 was one of the first that we had a book that explained how to adjust the rocker tensions cold! Then it stated that further adjustment would not be necessary! We did it that way and the thing fired off really nice right away and I havn't had to do any re-adjusting!
Also, be careful what gaskets you are using because the source you are using may have some "old stock" gaskets which don't blend well with the newer gasolines. Try to get the newest gaskets available or some really good aftermarket brands. You only need to do the job once not two or three times! I'm just a hobbiest, not trying to be an expert!.

Bruce

[Fat Cat]

I did run the motor hot a couple of times (like about 215 degress) and noticed the chrome intake schorched in a couple of places.

johnny

215 degrees is not hot. That is barely above boiling point got plain water. Most newer cars run around 220-240.

[EMSjunkie]

Yup ive done it all    
Dave

Yes he has..........and quite well    

Vance

Thanks buddy i thought you quit pickin on me :cry:
Dave

Thats about all I have to live for Bud, bustin' on you and Rayvyn is the high point of my life.

Vance

[EMSjunkie]

I just tore down the top of my 350.
noticed that #8 plug was completely fouled with.........well......."stuff" :?

I didn't really look at the intake gasket on that side, but I did notice that the vacuum port for the trans. and the PCV valve is in the #8 intake runner. I am wondering if that could be a contributing factor. I did notice that after it ran for a little while, it would smoke a little out the righ side. no smoke at start-up, just after about 2-3 minutes of running.

the new intake has the vacuum port in the same runner, I'm wondering about rearrainging the vacuum lines to pull from another source.

or.......are the valve guides wore and letting oil seep past?
the heads that I was running were 76cc chamber, nothing special.

I guess I'll see what happens now that I have changed intakes and heads.
went back with 462 casting # heads. 1.94 / 1.50 stainless steel valves with hardened seats. had them on the motor when it was in my sprinter
ported, polished, blended, and gasket matched, of course

Vance

[Jokester]

Had some trouble several years ago with rocker nuts loosening up.  Went to the Chevy dealer and bought new nuts.  You wouldn't believe how much tighter they were compared to the ones that had been on the engine for 20 years.  Cheap fix.

The only time I heard squeaking from the valve train was on an engine with pushrod guide plates.  Just a little mis-alignment and they would squeak like crazy.

my 2 cents.

.bjb

[speedracer]

Loose rocker arm bolts? Yep. Notice second rocker from right.



Result of loose rocker.



Entire story if curious

Now that looks like mine!  With the roller and all, wonder whats doing this?  Think I will get some brand new nuts to go on and see if they hold better----------------------johnny

[Mikej]

Over reving, spring binding, lifter sticking.

[reborn55]

Had that problem on a sbc and sbf.  piece of dirt in either lifter bore or pushrod caused rocker arm to not lubricate--made a heck of a squeal.