: Valve lash adjustment???
usa1 Jan 29th, 09, 01:14 PM I am ready to start my 396 and have adjusted the valves twice now,I went by the book first,brought up no. 1,adjusted after loosening and getting rod to just stop moving,then I went 1 full turn.I did 1,2,5,7 intake and 1,3,4,8 exhuast.then I turned engine to 360 degrees to no.6 . then I adjusted lash for intake 3,4,6,8 and exhaust 2,5,6,7 . Is this right?I cranked the engine and its popping fire out the right header.It seemed a little tight to me so I backed them off 1/2 turn.I then tried what another mechanic told me,bring up no. 1 adjust ,rotate harmonic balancer 1/4 turn,adjust no. 8,rotate 1/4 turn,adjust no.4 and so on in firing order.This dont seem right to me because all the lobes on the cam are different positions.I'm still getting fire on right side and not the left.And I noticed that the fuel I was dumping in carb to prime,some had eventually run out the right header pipe and left a spot on the floor.What am I doing wrong?
67CamaroRS/SS Jan 29th, 09, 01:47 PM Is this a stock cam? If the cam is hydraulic, then you have the correct procedure, but you don't get the pushrods to stop spinning. You are shooting for no up and down movement. Loosen them and tighten until the up and down movement is gone, then go 1/2-1 full turn.
67CamaroRS/SS Jan 29th, 09, 01:50 PM If the cam is mechanical, then you adjust the valves with a feeler gauge. You are going to bring up #1 cylinder and adjust certain intake and exhaust valves with the feeler gauge that it says to use. Place the gauge between the rocker arm and the valve stem and tighten the rocker nut until you feel drag on the feeler gauge.
Everett#2390 Jan 29th, 09, 03:54 PM Intake just finished closing, adjust same cylinder exhaust.
Exhaust just starting to open, adjust intake same cylinder.
This places the opposing lifter on the base circle of camshaft.
I find it the best method.
dawg Jan 29th, 09, 04:04 PM go here for a good explanation on how to adjust the right way
http://www.centuryperformance.com/adjusting-valve-lash-spg-149.html
docwilcar Jan 29th, 09, 05:27 PM 2390 has the fool proof way, and Harvey Crane likes it too!!!
ssdoug Jan 29th, 09, 05:31 PM Everett#2390 X2
67CamaroRS/SS Jan 29th, 09, 07:15 PM If it's a hydraulic cam, I use the method in the GM repair manual. The same method you have listed and it NEVER fails me. She starts right up every time and runs like a clock.
If it's a mechanical cam, then the GM manual lists that method as well, but it involves a feeler gauge.
BillK Jan 29th, 09, 08:20 PM And I noticed that the fuel I was dumping in carb to prime,some had eventually run out the right header pipe and left a spot on the floor.What am I doing wrong?
Ed,
First of all, if this is a new engine, you need to stop dumping fuel in it before you ruin the rings :( If you are putting that much that it is running out the header, it is waaaaaaaaay too much !!! The engine should start with just a couple of squirts from the accelerator pump, less than a thimble full of gas.
At this point you may have ruined the spark plugs with all the excess fuel. If you are pretty sure you have the valves right, then I would change the plugs and then double check the ignition timing. Squirt a shot oil in the cylinders while you have the plugs out to give the rings a break.
If you want to spray something in the carb to help starting, use a can of carburetor cleaner like Gumout. It will work just as good as gas and much safer. Once again .... not much is needed, a couple of seconds spray should be it. If it does not start, then something else is wrong.
Like I said earlier .... if this is a new engine, find out what is wrong before you ruin it :(
pdq67 Jan 29th, 09, 08:54 PM I have always set mine cold before light-off and then once up and running after the 15 to 20 minute's cam break-in that is another thread, I idle her down and adjust mine idling hot, solids and hy..
That's the way the old Mechanic's in town taught this pup back in HS and it is a pdq67 "feelie thing"..
Works fine by me all these years! Messy tho, but nothing three or four clean "red" shop towels couldn't handle..
pdq67
Z15CAM Jan 30th, 09, 02:12 AM There is no thing such as setting lash with a Hydraulic FT Lifter because Hydraulic Lifters require no lash. Instead you are adjusting the Rocker Nut to prevent the Hydraulic Valve in the lifter from reaching full travel, in which case the lifter will have a lash and bounce. A Hydraulic FT lifter is adjusted by tightening the Rocker Nut when the hydraulic lifter is sitting on the heel of the cam lobe with the hydraulic valve in the lifter lifter pumped up or at full extension and in which case anywhere between 1/8th turn to 1/2 turn is sufficient. The less the turn the less cam action will be lost due to the hydraulics or as know and less pump up.
This is my main Hydraulic FT Engine Tool and performed while the engine is idling:
http://farm4.static.flickr.com/3261/3238724776_25529bf857.jpg
Simply idle the engine and slacken each rocker at a time until it clacks thus giving it lash and wait a sec to ensure the lifter has pumped up. If the clacking stops you know the lifter has not pumped up and you can loosen the rocker nut some more. Once you are sure the lifter has pumped up and you have the clacking, tighten the rocker nut until the clacking stops then turn to the desired amount 1/8th to 3/4 turns - whatever.
Granted a fresh build or new cam installation requires hydraulic lifters to be set before firing the engine. When breaking in a Hydraulic FT cam I will use less then 1/8th of a turn and listen for a lash occurrence as this would indicate that there may be a lobe wear problem. In this case to set a Hydraulic FT Lifter you MUST ensure the lifter is sitting on the lowest position of the cam lobe the "HEEL" and ensure the lifter is fully pumped up. Tighten the rocker adjusting nut and spin the push rod until you feel a slight resistance - this is "0" lash - then turn the nut and as I say less then 1/8th of a turn or less for a cam break in. Many Hydraulic FT Racers will set their lifters at "0" lash before a run at the strip in order to gain a few rpm and prevent lifter pump up from limiting cam action.
I personally run 1/8th a turn if I run Hydraulic FT. That 1/8th will usually let you know if something is amiss before damage occurs.
pdq67 Jan 30th, 09, 08:13 AM Right Z,
I adjust hy-lifters by the feel of the spinning p/r while idling!
pdq67
67CamaroRS/SS Jan 31st, 09, 11:18 AM I have never been able to adjust hydraulics running without making a huge mess. Even with the tools you stick on the rocker that are supposed to deflect the oil down. Mine shoots oil alltheway over to the fender skirts.
Rookobird Jan 31st, 09, 06:40 PM On a never been run engine, would it help the lifters any to do the pre-lube thing with the drill in the distributor hole? (As far as valve adjusting goes)
Thanks,
John
deerhunter Jan 31st, 09, 07:53 PM I always soak my hydraulic lifters in a can of oil for a few hours. Then when I am ready to drop them in, I wipe the bottom of the lifter clean and put a dab of cam break-in lube on. I also ALWAYS prelube any engine I rebuild before starting it.
jerrys 67 Feb 1st, 09, 03:11 PM you know, the location of big block & small block valves are not the same.
identify each & adj accordingly as suggested.
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