Lifter problems new 460 build
Thread Starter
|
New User
Joined: Jan 2019
Posts: 9
Likes: 0
Lifter problems new 460 build
I am rebuilding a 1983 460 out of a one ton to put in an old 1/2 ton tbd.
Got everything back from the machine shop heads and valves needed little work he barely touched them. I installed my new cam, new hydraulic lifters, old pushrods and old non adjustable rockers. Book says to compress lifters at Tdc compression and make sure gap is .100-.150. I did this all the way around and had a couple I wanted to double check as they seemed a touch over .150 as I was using a rough stack of shim stock. I ground a .151 piece of steel and went back thru to double check today and two lifters will not compress again. I am 100% sure they all did yesterday when I checked them. I primed them all with a pump oil can before installation. What’s going on? I’m not an engine builder but I’m pretty confident with a wrench but am not sure why the compressed yesterday and today a couple will not. I’m also concerned that since I have rotated the crank I am loosing my molly on my cam, should I re molly the bottom of my lifters again ?
Thanks in advance guys. Been lurking but never had a reason to post
Got everything back from the machine shop heads and valves needed little work he barely touched them. I installed my new cam, new hydraulic lifters, old pushrods and old non adjustable rockers. Book says to compress lifters at Tdc compression and make sure gap is .100-.150. I did this all the way around and had a couple I wanted to double check as they seemed a touch over .150 as I was using a rough stack of shim stock. I ground a .151 piece of steel and went back thru to double check today and two lifters will not compress again. I am 100% sure they all did yesterday when I checked them. I primed them all with a pump oil can before installation. What’s going on? I’m not an engine builder but I’m pretty confident with a wrench but am not sure why the compressed yesterday and today a couple will not. I’m also concerned that since I have rotated the crank I am loosing my molly on my cam, should I re molly the bottom of my lifters again ?
Thanks in advance guys. Been lurking but never had a reason to post
Lead Driver
Joined: Mar 2004
Posts: 8,922
Likes: 153
You need to check the preload on the lifters, there should be .020-.060. Forget checking them the way you were, that will just get you in trouble. At tdc and the push rod just seated, there should be .020-.060 more to go before the fulcrum seats, that's your preload. Also make sure the machine shop set all the valve tip heights exactly the same height.
Thread
Thread Starter
Forum
Replies
Last Post
pinche002
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
3
Jan 9, 2018 02:01 PM
elsonite
FE & FT Big Block V8 (332, 352, 360, 390, 406, 410, 427, 428)
2
Jul 9, 2012 11:49 PM
bigdan1979f-250
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
4
Oct 19, 2006 10:53 AM
85351ho
Big Block V8 - 385 Series (6.1/370, 7.0/429, 7.5/460)
12
Aug 18, 2002 08:56 AM
