Hi all. I am going to attemp my valve adjustment and timing tomorrow on my 54 truck with a 62 235 in it. I have gotten great advise and info from people here. I just want to clearify that I am going to be doing it right tomorrow. I have down loaded the 235 valve adjustment from the stove bolt page. I will heat up my engine and follow the directions. I still have a question regarding the zero lash that people talk about. I have the hydrolic valves so I need to adjust to these specks. Is zero lash when the screw on top of the rod is just touching it or is it when you can not spin the rod anymore? I want to make sure I don't want to have things to tight in the engine that it might damage something. Thanks guys, Scottys 54
First off, are you CERTAIN that you have hydraulic lifters? I believe Nate recently spoke on this forum on how to check for that. Check the archives. It may even have been a response to your question , but I don't remember. Most 235's had solid lifters so I would be really certain of that if I were you. Also, Nate's description of proper valve adjustment procedure on Deve's antique truck website is right-on, easy and simple to follow. Andy
I will make sure to check the lifters. There was another guy that had a 62 235 engine in his truck and he had the hydrolic lifters. He had the same problem of his truck cranking for a long time before it would start. Someone mentioned the lifters need to get the oil pumping into them before they start up. My real question is this "zero lash" ?????? Am I at zero lash when the screw on top of the rod is just touching it, or is it tighter so that I can not spin the rod with my hand anymore? Scottys 54
Scotty, zero lash is when there is no space between the rocker arm and valve stem. Finger tighten the nut until there is no space, then go on to the next one. It's very important that you determine upfront if you have solid lifters or hydraulic ones, as the specs are different. In your '62 motor, you could have either. Normally though, the only motors that had hydraulic lifters were the ones that used the powerglide automatic tranny. Hopes this helps.
Hydraulic Lifter Adjustment O.K. Scotty ; Zero lash is when the adjuster screw just begins to touch the valve stem and there's no play . you should still be able to spin the pushrod if that particular cylinder is on TDC , there will be some drag on the pushrod but not a lot . If you're 100 % CERTAIN you have hydraulic lifters , adjust to zerolash then ad 1/4 turn preload BUT NO MORE , lock the locknut and move on to the next cylinder . once all 12 valves are adjusted , start the engine and run it @ 2,000 RPM's for at least two minutes , leave the rockerbox unscrewed , after two minutes allow the engine to return to idle and remove the rockerbox and with the engine idling between 600 ~ 800 RPM , adjust only the valves that are clicking , untill they just stop clicking , NO feeler gauge . the 2,000 RPM's ensures all the lifters pump up before you attempt to adjust them before they bleed back down again from lack of oil pressure . be aware that the 235 oiling system , when new , is _barely_ adequate to keep the lifters pumped up so after 3 ~ 4 minutes of idling it is normal for the lifters to bleed down and the valves to begin clicking . if your 235 is a typical engine , @ idle the oil pressure gauge will read either zero or the needle will barely clear the peg and the valves will clatter like mad , you'll be pi$$ed off and power and fuel will be wasted . the clatter should reduce sharply as the engine picks up speed . this engine is a 1940's tech industrial design and the bean counters forced the engineers to add hydraulic lifters , they should be discarded as a good running and properly adjusted Babbit Pounder engine sounds just like grammaw's sewing machine , a nice syncopantic clatter of gently ticking sounds..... Music , really it is . The boob who told you the lifters need to pump up before the engine will start readily , should have his tools and bangers taken away as he doesn't Ken how it all works ~ bled down lifters will help rapid starting by ensuring full closure of the valves , vital to easy starting @ slow cranking speeds . Good luck and DO NOT allow anyone to talk you into turning the adjusters 1 - 1/4 turns after zero play ! . Maybe someone should mail this addendum to Deve ? .
