setting the rockers/tappets

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scot the sniper
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setting the rockers/tappets

Post by scot the sniper » Sun Oct 25, 2015 10:23 pm

hi guys what is the prosedure i no the firing order is 18436572 if i set cylinder 1 what is next is it 8 or is this a stupid question what is the order to set them in please

cheers
scot

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bhm1712
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Re: setting the rockers/tappets

Post by bhm1712 » Mon Oct 26, 2015 9:02 am

If this is a standard rocker arm and lifter set up then there is no adjustment. You simply torque the rocker arm nuts down to 20 foot pounds and leave it. The Pontiac valve train is non adjustable and the hydraulic lifters will take up any excess clearance.
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scot the sniper
POC Newbie
Posts: 31
Joined: Fri May 08, 2015 11:38 pm
Membership No: 15-F026
Year: 1979
Model: trans am
Engine: 350
Name: scot
Location: scotland
Location: scotland
Contact:

Re: setting the rockers/tappets

Post by scot the sniper » Mon Oct 26, 2015 9:12 am

i have already done that but robin at autopontiac said they need set and i looked on youtube and they have same rockers as mine and they are setting theres now im confused. it says to get both rockers down and level check the pushrod for play if there is play adjust it so the pushrod is just begining to get taught then give it half a turn and that would be it set. i must admit it doesnt say anything in the haynes manual on setting them. can you verify this is true mate if so mine are already set then and need no more adjustment just dont want the rattle that ppl go on about.

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bhm1712
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Re: setting the rockers/tappets

Post by bhm1712 » Mon Oct 26, 2015 1:14 pm

If it's got pressed rocker arms with a ball pivtots and nuts as it came from the factory then 20 foot pounds torque on the but and they are set - the lifters accommodate for any slack in the valve train. If they are after market style then they will need to be set. Post a pic if you don't know for sure. Is it standard or have you modified then cam shaft and valve train!?
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bhm1712
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Re: setting the rockers/tappets

Post by bhm1712 » Mon Oct 26, 2015 1:19 pm

If you attempt to set the valve lash on a standard valve train all you will achieve is a rocker arm which is either too tight on the ball pivot or too loose which leads to excessive wear of the valve train and possibly even further damage elsewhere. The idea is that the nut is tightened to the specified 20 foot pounds which means the ball pivot is pressing down on the rocker arm perfectly for it to pivot without play. The hydraulic lifters fill with a metered amount of oil when running so that any excess lash is removed. If you try to set the lash by the method you have seen then you will be forever adjusting it because once you have set it, when the engine has ran and the lifters have filled up and then drained down again the lash setting will be different again.
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Northern England & Midlands Rep

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bhm1712
Site Admin
Posts: 2677
Joined: Sun May 10, 2009 4:58 pm
Membership No: 20-607
Year: 2001
Model: Trans-Am WS6
Engine: 350
Name: Ian
Location: Nottingham
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Contact:

Re: setting the rockers/tappets

Post by bhm1712 » Mon Oct 26, 2015 1:21 pm

If you have any doubts, give robin a call again, as he will be able to clear this up for you but you need to make sure he knows if you have a standard factory valve train or after market.
Ian Hopkinson - Membership Manager & Forum Administrator
Northern England & Midlands Rep

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scot the sniper
POC Newbie
Posts: 31
Joined: Fri May 08, 2015 11:38 pm
Membership No: 15-F026
Year: 1979
Model: trans am
Engine: 350
Name: scot
Location: scotland
Location: scotland
Contact:

Re: setting the rockers/tappets

Post by scot the sniper » Mon Oct 26, 2015 1:47 pm

forgot to mention i bought a cam from robin and it is slightly got more lift does this make a difrence or just keep it the same?

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