Lifter replacement

[MiGorda]

Here's a couple pictures of my Lunati cam and lifters - one was collapsed and one was mushroomed (the one with the dish), I had a hell of a time getting it out because it was flared at the bottom. Whether you have a stuck valve or not, you're cam and lifters are suspect too (like everyone above tried to tell you). I was able to find single Lunati lifters somewhere, maybe Summit racing (but I don't See any now). I replaced them and ran it for a couple weeks, or so, until the shiny stuff in the oil caused my rod bearing to spin. Then the piston was going up too high and KNOCKING INTO THE HEAD, making a real loud banging noise, like you describe). Drain the oil and look for metal filings and/or glitter in the pan or the filter. That'll tell you.

www.gmt400.com/threads/my-flat-tappet-cam-wiped-out-so-i-decided-to-go-roller.60167/post-1277333

My Flat Tappet Cam Wiped Out So I Decided To Go Roller

A little background: About 4 years ago, my '88 C1500 with the 5.7L TBI engine started overheating on me. I found the head gaskets blown. I knew the swirl port heads and peanut cam were about useless so, I decided to "upgrade" to better parts while trying to keep it fairly cheap - yeah right...

www.gmt400.com

Thanks for your reply, good info. I agree that the cam could be damaged but I tried this process to get it out but put too much pressure with my clamp, so maybe it is not too much stuck, now is almost imposible to grab it with the clamp.

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I just spread some WD-40 and maybe tomorrow try again.

Anyway, my next step is to remove the head and see the damage in the valves.

Regards.

 

[Hipster]

The whole thing seems to be a wild guess.

STOP.

^^^this, along with everything else he said.
at 9k miles on the build the lifter is not stuck for varnish. It's cheaper to throw a block away and get another one than to have lifter bushings done. It's not something every machine shop is capable of.

 

[Schurkey]

There is no "little damage" on a cam lobe. It's good...or it's scrap metal.

You are in the process of wrecking that lifter bore.

 

[Hipster]

There is no "little damage" on a cam lobe. It's good...or it's scrap metal.

You are in the process of wrecking that lifter bore.

Yeah , looking for a cheap fix for which there isn't one.

I have had situations where I had to get lifters "up", wrangle the cam out, then push the lifters into the cam cavity to fish them out.

 

[Hipster]

@MiGorda Schurkey summed it up best. There is no "little damage" to a cam lobe, either it's perfect or the cam is junk. The condition of the cam is what you have to determine and it's why I said that a new lifter may not be a solution. "ALL OF US" responding understand perfectly. A new lifter might last less than 10 minutes on a bad cam lobe and send more metal fragments into the oil/engine. Again, there is no $8 cheap lifter fix for this without looking deeper.

 

[Schurkey]

Anyway, my next step is to remove the head and see the damage in the valves.

Why do you need to remove the head? If the valves are damaged from excess clearance, the damage will be apparent above the retainer--where the rocker arm has been banging against the valve tip.

There may be MORE valve damage than just the tip...but there shouldn't be valve damage anywhere else if the tip isn't brutalized.

It's not like the valve seized in the guide, and got hit by the piston.

 

[Hipster]

Why do you need to remove the head? If the valves are damaged from excess clearance, the damage will be apparent above the retainer--where the rocker arm has been banging against the valve tip.

There may be MORE valve damage than just the tip...but there shouldn't be valve damage anywhere else if the tip isn't brutalized.

It's not like the valve seized in the guide, and got hit by the piston.

Idk , kinda sounded like lash was cranked down until there was contact but I would be looking at the cam closely before pulling a head. Not really enough info here if coil bind, or guide to retainer clearance could have been an issue before piston to valve contact. .465 lift, stock, springs etc. is a pretty big shortcut. Offhand .465 would have called for something like a 110-115lb seat pressure like Z28 spring which can be had for under $60/set, and not an 80 lb. stock one. Why this happen he asks. The guy that built the engine didn't know what he was doing.

 

[MiGorda]

There is no "little damage" on a cam lobe. It's good...or it's scrap metal.

You are in the process of wrecking that lifter bore.

Ok, I don´t want to debate because I don´t have experience about it. However I´ve done some works to my other car, I've replaced the oil pump to my PT Cruiser GT, that´s not easy and the job was perfect, also swapped the turbo and other little jobs. To my Tahoe replaced the oil pump and the clutch, yes the clutch, I put it an LT1 T56, well not me, my mechanic.

So please explain me, why there are many cars circulating right now with its engine worn out, including the cam?

You know these engines are strong, even with this valve damaged, the truck run "well".

Anyway I appreciate your advices and if i need to replace the cam and the whole kit I will do it but I want to contemplete a lower damage.

 

[Hipster]

Ok, I don´t want to debate because I don´t have experience about it.

And there are several of that do have the experience. A damaged lobe will take out a new lifter in very short order. 10 minutes or less. You not understanding doesn't make what everybody else is saying invalid. YOU NEED TO EXAMINE THE CAM before coming up with a repair plan. Shoving a new lifter in it is what you want to hear so go for it and let us know how that works out.

 

[MiGorda]

And there are several of that do have the experience. A damaged lobe will take out a new lifter in very short order. You not understanding doesn't make what everybody else is saying invalid. YOU NEED TO EXAMINE THE CAM before coming up with a repair plan.

Ok, I understand. Anyway I'll try to pull out the lifter "slightly" and if comes out maybe the damage is very little and I'll keep the cam, if I can´t pull it out then remove the cam.

It´s not invalid of course, I know is important to be realistic and you are but there is nothing wrong being optimistic, I'm not against saying you, I´m just looking options, in case there are.

Thanks.