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New to me 1979 f150 with a 351m. Just pulled the valve covers to find 2 dropped push rods on #1. Gonna pull the rockers and try to fish them out. Assuming they’re not bent, is a valve job my next step?
With them down, valves are closed. I'd do a leakdown test with air first. Put air in the plug hole, see if it comes out intake or exhaust (indicating leaking valve) ... and if none is detected, see how long it'll hold pressure? Valves might be fine.
I would want to pull the intake too though, look see what's with lifters, etc.
With them down, valves are closed. I'd do a leakdown test with air first. Put air in the plug hole, see if it comes out intake or exhaust (indicating leaking valve) ... and if none is detected, see how long it'll hold pressure? Valves might be fine.
I would want to pull the intake too though, look see what's with lifters, etc.
if that’s normal, what causes rods to drop? poor valve lash settings? I’ve read that sticking valves can cause the rods to drop. Stay tuned
if that’s normal, what causes rods to drop? poor valve lash settings? I’ve read that sticking valves can cause the rods to drop. Stay tuned
Both on one cylinder? Could be a previous owner missed lifters when putting them in and never knew it or was too lazy to revisit it after a start up. The one tip I do see is so far down, it's missed the lifter or is bent bad or broken I think ... why I'd at minimum pull the intake and valley pan gasket.
Has this truck sat for a long time before firing it up? Only successful fishing expedition I have ever had was on an engine was FE style..
not sure how long this sat. Previous owner had it for a couple of years but didn’t do much on it. When I test drove a few months ago, lots of hesitation with gas but assumed it was related to a vacuum leak. The steering and suspension was so loose that I wasn’t driving too fast. Let the investigation begin
Found those pushrods I was looking for. Fished out both with a magnet and the exhaust lifter. Looks like the top of the lifter is missing somewhere, as is about 2” of one of the push rods. I tried fishing around with a magnet but didn’t find any other pieces. Looks like the intake is coming off.
That's extreme. check the valves, I'd figure on pull the head.
you thinking sticky/stuck valve causing the rod to bend and destroy the lifter? any way to unstick it without removing the head? I've heard of spraying it down w/ WD40 and tapping on the top of the valve stem.
I would think more like they were floated and the piston hit them, if that's possible with your pistons. even if your lifter locked internally fully extended it wouldn't cause any damage . it's possible the lifter came apart and the push rod got in the wrong place and was destroyed causing damage to the other in the process.
One thing is for sure, to destroy push rods like that it came up solid on both ends.
I would think more like they were floated and the piston hit them, if that's possible with your pistons. even if your lifter locked internally fully extended it wouldn't cause any damage . it's possible the lifter came apart and the push rod got in the wrong place and was destroyed causing damage to the other in the process.
One thing is for sure, to destroy push rods like that it came up solid on both ends.
any recommended next steps short of pulling the head? I am planning on removing in the intake to find the other missing pieces of the pushrod and lifter. also want to pull/examine the lifter on the intake valve as I can't really see it through the head. I have a local head shop i've used in the past that could check my valve seals and seats as well as springs if necessary.
Unless that cylinder passed a leak down test and unless the valves freely move, I'd pull the heads for a look once the intake is off. I'd also want to at least pull the pan to check for shrapnel. If this is a 4wd, pan is easy enough to pull while engine is in frame still. Just jack, frame on stands, front axle hanging, just drop frame end olf track bar. Rear pan bolts, use 1/4" drive long extension with socket to pass starter.
