Inliners International Forums General Discussion Engines 250 engine help

ok guys i have a 1972 chevy 250 replaced all the lifters and have adjusted the the valves but i still have a valve ticking and i cant figure this one out any help?

i think it is number 5 and i can adjust it down and the engine boggs bad but it is oiling like crazy

Did you inspect all the rocker tips and valve tips for excessive wear.

And rocker arms and balls? Stock rockers sometimes have horrible looking wear witness marks, especially with grooved balls.

For both new and good condition used stock rockers I lap the ball into it's socket with some diamond abrasive. Put a tapered spud into your drill press and spin it slowly. The ball will stick on the taper and you hold the rocker with your hands under it, working it around till it's smooth. Clean very well afterward to get rid of the diamond grit.

Necessary? I don't know but works for me. Try it sometime. Feel how rough the rocker ball is in it's socket on a brand new rocker. After a little lapping it's nice and smooth and has much greater contact area which should result in quieter operation and longer life. I believe the best outcome is when the ball naturally rotates while running, evenly distributing wear. Grooved balls and little contact area due manufacturing inaccuracy seems unlikely to encourage natural rotation.

ok guys i have an update for you all about the valve ticking
it was the oil pump i now have 40-35psi at idle and 25-30psi in gear and tick is completely gone plus i am using castrol 20w-50,4 qts. i am so happy to have this issue gone now i can focus on cam,headers and intake with carb

Thats good news that its fixed. Problems like that can be aggravating to diagnose.

oh my god
that sound is back and is doing the same thing what can this be and will me replacing the cam help
i am at a loss for words on this
i put new oil pump, rocker arms, push rods, lifters, 20w-50 oil,water pump(it was going out) and i have them adjusted just like i was told on this site and it still makes sound
it sounds like number 4 or 5 now heres the weird part i can move lifters rods and arms to another cylinder and the same thing it stays on 4 or 5 cylinder but it will stop then start while engine is running and no change in oil pressure someone please help me i dont want to hurt the engine or replace it
thanks guys

I'll bet your camshaft and lifters are both shot.

thats what i hope but the lifters are new

Cam/Lifters or Piston Pin?
I have a near-worn out 250 like this - the lifters tick, and yet if you go 1/2 turn tighter, the engine will miss - too tight. The lifters are pretty worn, on the really bad ones I have to swap in "new" (ie out of the grab-box) used lifters til I get a decent one. Then, the rocker has to be set so it just barely won't tick or misfire.

But, you said you can move things around and it is always the same cylinder - that makes me wonder if it is a loose piston pin, sounds a lot like a lifter, intermittent - worst when just coasting with no load on the engine - could this be it?

How do the bottoms of the lifter[s] look on the ticking cylinders? Still convex as when new or concave? That would be another hint.

You can pull the plug wires off of those cylinders one at a time with the engine running to see if it stops ticking/knocking when you do this. If removing the spark load eliminates the noise, it is probably indicating problems deeper inside the engine,ie. wrist pin, collaped/broken piston or rod bearing issues.

well i thought it maybe something else too but once i bottom out the lifter which is new the ticking will somewhat go away but yes engines runs bad like it is missing it will tick while coasting but not every time and it will just stop while giving it gas but come right back
it does not burn ant oil at all that i can tell only leaks it around valve cover due to me taking it on and off soooo much and the lifters look fine but that are new

ok i will try that in just a few minutes cnc dude #5585
and if it stays ticking?

ok i tried the plug wire trick and the ticking is still there and it really sounds like the rocker arm area
i don't get it

Ok, since you said you swapped the rockers from those cylinders to another area of the engine and the noise remained constant to the #5 & 6 cylinders, you might have a bad cam lobe or two on the cam on those cylinders. With the valve cover off of the engine, can you spin the engine over with the starter and see if the valves seem to be opening the same on 5 & 6, as other valves at the front of the engine. Take the coil wire off of course.

that i have not done yet
and the engine only has like 114k miles on it and i know for sure the miles was long trips driving by my grandmother who drove it like she she was running for the law lol
however it was parked for 4 or 6 years and now this is where i am with it

I am new to the inlines and have been learning alot from my recent reading.. What is the possibility someone did some past honing to clean up some cyl walls and you might have some piston slap going on? Not sure if its something that can happen with the inlines due to geometry of the engine so feel free to tell me I am a dumbass.. Just thought I would drop my 2 cents.

Although since it was grandma's engine one would "assume" it had never been apart.

Skez

as far as i know it has never been opened but i will check with dad to make sure

something that can happen with the inlines due to geometry of the engine

Not sure what you mean?

Your lifters were new until you ran them on a bad camshaft. Now your new lifters are bad too.

Noise possibly comes and goes as the lifter rotates from a more to less worn position.

Not saying this is your problem for sure, but I'm placing my bet here.

Piston slap, I am not familiar enough with the inline 6's to know if it can happen (it might not due to geometry, not sure if they are a totally squared motor or not). but with most v8 if you clean up just one cyl a bit with a hone or due to high milage the rings/piston can have a slap sound called again piston slap, in the old days mechanics would knurl the piston on a cheap quick rebuild but this often caused slap after the knurling wore down. This tick can at times get a little quieter after running for awhile or right after an oil change due to the new viscosity of the oil but always returns.

Try and wiggle the offending cylinders valve when the n engine is off. See if there is noticable valve movement, it may be worn guides/ valves.

114K on a 40 year old car engine, it will be worn out. Tom

worn out my god you must be kidding ...
so i guess i need to rebuild it then right?
that just doesn't seem right no smoke no oil burning just a ticking sound and it is worn out ...amazing
never the less thanks guys for the help this site is killer

I highly doubt the valves are making your ticking noise.


MBHD

Odied,
Just want you to check things out.

I had a stock 250 in a 67 chevelle, bought it after sitting for years. Started driving it regularly and it developed a bad tick, pulled the valve cover and found a broken valve spring.
Simple fix.

Your engine will have many more miles of stock use in it. But when you start pushing it harder, those 40 year old parts will let you know they are past their limit.
Lets figure out what the problem is. Tom

ok

so look for aa broken valve spring ok i will do that this week and hope that is what it is
thanks for the help