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I really need some help !
I have a 69 Firebird and I just put in a new motor about two weeks ago. It's Pontiac 400 and I installed a Crower cam and a set of Rhoads lifters. The engine started fine and runs good but I can't get the lifters to stop tapping.
The folks at Rhoads have been very helpful and I've followed their instruction but they are still tapping.
I don't have much experience with adjustable rockers. All my other engines have had non-adjustable rockers.
With the intake in place, Rhoads says to get number one at top dead center with the rotor pointing to the number one distributor contact. Loosen the rockers until the pushrods can be moved up and down. Tighten the rockers until there is no up and down play with light pressure, at this point you should be able to push on the pushrod and feel the plunger spring move up and down then tighten another 1/2 to 3/4 turn. Rotate the crank 1/4 turn and go to the next cylinder in the firing order. On some I can feel the plunger move but on others, as soon as the pushrod play is gone the pushrod will not move up and down no matter how hard you push.
I've tried everything, 1/4 turn,a half turn, 3/4, a full turn, I've adjusted them a dozen times and nothing seems to work. CAN ANYONE HELP?
 

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Some Punk Kid
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Sounds like you had them too tight. like they said on the phone just jiggle the pushrod up and down till all the slack is taken up. Before you even go the extra 1/2 turn see if you can get the internal spring to go up and down in the lifter. Push the rocker down on the pushrod side and you should have a 1/8" gap between the rocker arm and the valve stem. If you dont have any daylight in that area its too tight.
 

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69 Firebird

I was going to try Rhoads lifters on my 76 firebird because the cam I installed I couldn't get it to idle right now for that year and the cam they said just tighten down on the rocker arms so I did it wouldn't run correct like it had a full cam so what I did is adjust the lifters by loosing all the rockers and tightened them them till they stopped making the clicking sound then I gave them I think it was a half turn it smoothed it out perfect I didn't have to buy the Rhoads lifters after all.
 

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"Q. Why do Rhoads Lifters sound similar to solids at low rpm?
A. With Rhoads Lifters there is never any clearance in the valve train. The ticking noise you hear is simply a slightly accelerated valve-closing rate much like that of a solid lifter. This sound gradually disappears as the rpm increases."

http://www.rhoadslifters.com/Pages/FAQs.html
 

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Hates: Liver. Loves: Diesel
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Rhodes lifters are a fast bleed down lifter to effectively decrease duration and lift at lower RPMs. They're supposed to tap because they don't hold pressure at slower revs.

They sound like a collapsed lifter because that's basically what they are. The high bleedown doesn't necessarily allow "lash", that is to say they don't allow airspace between the pushrod and lifter at a static setting, but with only the spring and reduced oil retention, the plunger gets thrown around and lets lash occur during operation.
 

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aka Duke of URL
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pmeisel said:
Yeah, big write up in Hot Rod last year.
Sounds good in theory. I know they were popular years ago.

From what I read on their site, they can be most beneficial. How many here have had good results?
 

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Ran 'em in my built 462 Buick & just loved 'em. Would certainly use again. Best way I know of to get the max power at high rpm, but with a usable lumpy idle and some vacuum at low rpm with a huge cam.

How huge? Was driving on an early test drive & heard 't-t-t-t-t-t-t' from engine, then 'tink - tink -tink' from below me. The 1" wide wingnut I had rednecked 2 threaded rods together with to handle my 6" tall air cleaner had dropped into the intake, in the intake valve on #3, bounced around the combustion chamber for about 3 seconds, and gone out the exhaust valve and down my 4" open exhaust (hadn't finished real exhaust). Took head off & sure enough, there were dimples in the top of the KB piston, but no valve damage or head damage. I'd say that's a big cam. The Rhoads would let it idle at about 550, if you wanted. Ran it at 700 rpm & kept the stock vacuum assist on the brakes. And it pulled like a freight train from stall to 5000 rpm.

Rhoads rocks on big displacement and big cams, IMHO.
 

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aka Duke of URL
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Sounds good to me. I was thinking a mechanical cam had different ramp events (more agressive requiring stronger springs) but if you can take these and put on a solid cam without an adjustable valvetrain, that's heck of a hot street item if you get my drift...

Guess you with have to talk with their TECH to see how far you can go with spring pressure before it affects them... :confused:

-SIMILIAR CURRENT THREAD-
 

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As far as lash goes, I ran triple valve springs and adjustable 3/8" pushrods. It was a pain, I remember, but, IIRC, I ran the engine to full warm up, revved at 3k for a moment, then shut it off quickly. This, in theory, gave me full pump on the Rhoads for setting tension to where the pushrods would just spin with index & thumb.

I did cut an old set of valve covers so that I could adjust run & adjust without pulling the covers & oil wouldn't go everywhere.

Also remember, that once I got it running exactly right, I pulled one of the adjustable pushrods & measured it, so that I'd have a baseline in the future.

I know that all of this may not be applicable in your application, but these were great suggestions from the guys at Poston Buick Performance, at the time (this was '93).

BTW, this 462 Buick was in a '67 Ford truck (4WD with 38" tires), and backed by a TH400 & NP205, with an 850 Thermoquad sitting atop. Also ran one 18" long battery out of a city bus that must have weighed 80 lbs. Stump puller.
 

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Save a horse, Ride a Cowboy.
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KULTULZ said:
Sounds good to me. I was thinking a mechanical cam had different ramp events (more agressive requiring stronger springs) but if you can take these and put on a solid cam without an adjustable valvetrain, that's heck of a hot street item if you get my drift...

Guess you with have to talk with their TECH to see how far you can go with spring pressure before it affects them... :confused:

-SIMILIAR CURRENT THREAD-


I'm pretty sure Rhoads are for hydraulic cams only. I don't know where you read they are for solid lifters in this thread.

Rhoads lifters absorb the lift and duration due to their "low internal oil pressure". They will make any cam softer than a stock lifter.....all the time, but have less of an effect at mid range rpms.
 

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rhodes

I had a set on a 454" chev motor---yes they do sound like solids,even when adjusted properly, and yes I liked them --replaced them with standard lifters,and felt I had lost some snap. GOOD PRODUCT
 

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aka Duke of URL
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xntrik said:
I'm pretty sure Rhoads are for hydraulic cams only. I don't know where you read they are for solid lifters in this thread.
From Their Site FAQ;

Q. Can I run Rhoads Lifters on any hydraulic cam?

A. Original Rhoads Lifters are recommended for performance hydraulic cams only. They may also be used with factory high performance cams. Rhoads V-Max Lifters are generally recommended for performance hydraulic cams but may also be used with performance solid lifter cams. Stock cams are generally not recommended as reductions in lift and duration on stock cams have very little effect on performance gains.
 
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