self align rockers or not?
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From: Taxahoma
self align rockers or not?
I ordered 1.6 self aligned rollor rockers from jegs and upon startup I have ALOT of valve train noise. Got on the phone with jegs and after visual verification I explained that it looks like my 87 has guide plates, he asked if the original stamped rockers had a dimple for the valve stem, I said no. Basically he's saying that I need non self aligned rockers. This after there tech support said I needed self aligned and a local shop said this also. So which is it guys? Am i returning these or not?
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From: Taxahoma
Re: self align rockers or not? (Black87c4)
Done some searching, some are saying that the plates really aren't guide plates. Well if this were true I would have dimples on my stock stamped rockers where they touch the valve stem correct? Mine are smooth and have no dimples which would tell me I actually have real guide plates and non self aligning stampled rockers so still the same question, can i use the self align roller rockers that I have now but just remove the guide plate. Would the guide plate cause the noise that i'm hearing. I've done the valve adjustment twice now so I'm sure it's correct. ????
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From: SE NY
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Re: self align rockers or not? (Black87c4)
I'm not sure about '87 but my '88 had non-functional guide plates and self-aligning rockers.
You can check to see if your push rods contact the guide plates as they move; if the guide slots are wide compared with the push rod diameter they were non-functional. But with a 1.6:1 RR ratio there might be some interference.
It would be a good idea to remove the stock guide plates as they can do no good and may do some harm.
On your engine you can either use self-aligning RRs without guide plates or non self-aligning with guide plates; it's not good to mix though.
You can check to see if your push rods contact the guide plates as they move; if the guide slots are wide compared with the push rod diameter they were non-functional. But with a 1.6:1 RR ratio there might be some interference.
It would be a good idea to remove the stock guide plates as they can do no good and may do some harm.
On your engine you can either use self-aligning RRs without guide plates or non self-aligning with guide plates; it's not good to mix though.
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From: Taxahoma
Re: self align rockers or not? (65Z01)
I just went out and looked, some of the pushrods have been scratch a little so I'd say they are hitting the guide plates. I assume this would be enough to make the noise I'm hearing, it's pretty loud. Thanks. So if they aren't real guide plates how do the stock rockers stay put since they don't have the dimples?
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Re: self align rockers or not? (Black87c4)
If they are touching on the sides yours may be functional guide plates.
In any case it looks like you need to remove them; which means removing the screw-in studs to get at them.
In any case it looks like you need to remove them; which means removing the screw-in studs to get at them.
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From: Taxahoma
Re: self align rockers or not? (65Z01)
If i take the plate off do I need to put a washer under the stud so that the length is the same? Looks like the rocker will sit a little lower if I don't.
Here's what I have or should I just get the correct rockers?
[Modified by Black87c4, 10:04 AM 5/30/2003]
Here's what I have or should I just get the correct rockers?
[Modified by Black87c4, 10:04 AM 5/30/2003]
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Re: self align rockers or not? (Black87c4)
The RRs can ride up/down the studs and are held in position by spring/pushrod pressure below and the poly-lock pressure from above.
You shouldn't need a washer for spacing so long as you can set zero lash plus preload and poly-locks still have a good grip on the stud.
You shouldn't need a washer for spacing so long as you can set zero lash plus preload and poly-locks still have a good grip on the stud.
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Re: self align rockers or not? (65Z01)
The RRs can ride up/down the studs and are held in position by spring/pushrod pressure below and the poly-lock pressure from above.
You shouldn't need a washer for spacing so long as you can set zero lash plus preload and poly-locks still have a good grip on the stud.
You shouldn't need a washer for spacing so long as you can set zero lash plus preload and poly-locks still have a good grip on the stud.
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From: Bartlett IL
Re: self align rockers or not? (Black87c4)
DO NOT use self aligning rockers with guide plates. You cold end up with a bind of the pushrod possibly bending it. Use one or the other, not both. You may be better off with the guide plates and non-aligning rockers.
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: self align rockers or not? (Dominic Sorresso)
DO NOT use self aligning rockers with guide plates. You cold end up with a bind of the pushrod possibly bending it. Use one or the other, not both. You may be better off with the guide plates and non-aligning rockers.
The pushrods/rocker system should only be located in two places.. one at the cup on the lifters, and one at EITHER the guideplates/heads (for non-self aligning rockers) OR at the valve stem (for self-aligning rockers). BUT NOT BOTH. Locating at three places can cause binding and maybe worn/bent pushrods.
A push rod, is by its very nature, a two-force member. Forces should act in compression only along it's longitudinal axis, which is why they're so scrawny.
I guess both ways of locating the pushrod/rocker were equally good or bad, because Chevy couldn't decide what to use and switched back and forth.
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From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
Re: self align rockers or not? (Black87c4)
If i take the plate off do I need to put a washer under the stud so that the length is the same? Looks like the rocker will sit a little lower if I don't.
Here's what I have or should I just get the correct rockers?
Here's what I have or should I just get the correct rockers?
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From: Taxahoma
Re: self align rockers or not? (CentralCoaster)
It's my understanding that the LT4 uses self aligning so I assume they aren't so bad and I don't feel like waiting yet another week or two to exchange them so the guide plates are going out. Is there such thing as a longer stud for self align vs non self align? There's not much to grab ahold of.
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From: Bartlett IL
Re: self align rockers or not? (Black87c4)
Why is a longer stud going to help? Without the guideplates the stud will be lower in the head and the rocker will effectively be closer to the valve. That would necessitate getting shorter pushrods. Unless the studs you bought maintain the same geometry by positioning the rockers like the guide plate studs do? Regardless, I would invest in an adjustable length pushrod to verify your valvetrain geometry.
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From: Taxahoma
Re: self align rockers or not? (Dominic Sorresso)
With or without the guide plate the rocker is still in the same position, with the guide plate removed the stud is now lower and I can't get a good bite on it. With the longer studs i now can. Make sense :confused:
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From: Bartlett IL
Re: self align rockers or not? (Black87c4)
I don't know what you mean by "getting a good bite". But unless the "longer stud" positions the rocker further up the stud so that it matches where the rocker is positioned using the guide plates, you will have a valvetrain geometry problem. If the Hex portion of the stud is elongated so as to make up the space taken up by the guide plate, then you should be OK. BUT, I would still check the pushrod length with a length checker.
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From: Taxahoma
Re: self align rockers or not? (Dominic Sorresso)
I'm far from a valve expert but doesn't the spring and push rod determine where the rocker sits? Even with the stock stamped rockers on they don't sit on the bottom of the stud, they float above it. I already screwed one of the longer studs in the rockers "looks" the same as the ones with the guide plate still there, I can now screw the lock on because I now have enough thread showing. See what I'm getting at? correct, wrong :confused: as I said i'm not an expert on valves. Anyone?
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From: Bartlett IL
Re: self align rockers or not? (Black87c4)
If you are thinking that the rocker is "suspended" on the stud held up by the valve stem and pushrod, you are very much mistaken. The rocker seats on the stud as the base of the stud flares out. That's also why its important to make certain the fulcrum of the rocker is correctly aligned to the stud. I think you may be ok because it sounds like the studs you bought have an extra thick hex section making up for the lack of guide plates.