Bad hydraulic lifter
Thread Starter
Cruising
Joined: Jul 2013
Posts: 10
Likes: 0
From: El Lago TX
Bad hydraulic lifter
I have discovered that the intake lifter for cylinder #5 in my 350 has a concave surface. Getting it out was a little tough, but I managed to get it out. Do I need to now replace the cam as well? If so, what is a good replacement for the stock cam provided by GM in the 1979 Corvette 350? Because of the car's age I don't need to go through emissions testing, so perhaps can go for additional performance? The engine is still completely stock with 95,000 miles on it. I am replacing all lifters, push rods, and the intake manifold. Thanks for any recommendations!
Race Director
Joined: Apr 2007
Posts: 11,152
Likes: 890
From: South Western Ontario
Yes, replace the cam.
Something like this is a nice upgrade cam size for mostly stock.
http://www.summitracing.com/parts/lun-80350lk
Something like this is a nice upgrade cam size for mostly stock.
http://www.summitracing.com/parts/lun-80350lk
Melting Slicks
Joined: Jul 2006
Posts: 2,291
Likes: 492
From: Salmon Arm, BC
Thats bad news.... the problem with a lifter that goes bad and is run for an extended period of time is all the little metal shavings/bits get circulated through your engine in the oil, and can do damage to cylinder walls and bearings.
It's clear you have to replace the cam and lifters, so you might as well pull the engine tear it down and inspect the internals for damage. If your on a budget, you may get away with a rering/hone and new bearings plus the cam and lifters and timing set....you won't know until you look.
With todays oils, i'd stay away from a flat tappet cam, You have first hand experience of what can happen. The hydraulic roller cam is quite abit more expensive but in my opinion is the only option available that makes sense. It's about $1000 for roller cam/retro roller lifters/new pushrods.
The comp cams XR264HR would be a good fit for what your asking for. Its 212/218 @ .050 and .487/.495 lift. Its a mid range cam that performs in the 1500-5000 RPM range and topping out at about 5500 RPM. It will also have better results if you add headers and an good flowing dual plane intake.
It's clear you have to replace the cam and lifters, so you might as well pull the engine tear it down and inspect the internals for damage. If your on a budget, you may get away with a rering/hone and new bearings plus the cam and lifters and timing set....you won't know until you look.
With todays oils, i'd stay away from a flat tappet cam, You have first hand experience of what can happen. The hydraulic roller cam is quite abit more expensive but in my opinion is the only option available that makes sense. It's about $1000 for roller cam/retro roller lifters/new pushrods.
The comp cams XR264HR would be a good fit for what your asking for. Its 212/218 @ .050 and .487/.495 lift. Its a mid range cam that performs in the 1500-5000 RPM range and topping out at about 5500 RPM. It will also have better results if you add headers and an good flowing dual plane intake.
Thread Starter
Cruising
Joined: Jul 2013
Posts: 10
Likes: 0
From: El Lago TX
Thanks for the suggestions, guys. Much appreciated. I haven't done this for a long time, so am having fun! I see that roller rocker arms are not much more expensive than the standard OEM rockers. Are they worth the extra cost? Since I am going to replace the camshaft a fresh timing chain is on the list of things to replace as well. Also a fresh oil pump.
Instructor
Joined: Mar 2013
Posts: 205
Likes: 20
It maybe cheaper to have a new engine built for you or start with a crate engine and do it yourself.
Keep your original engine for number matching needs. Prepare it for longterm storage.
I'm having an engine built by Carolina Machine Engines (CME). I have toured their facility (Johnston, SC) and was very impressed. They are a Production Engine Remanufacture. They spin test the engine with heated break-in oil with the proper additives. The actual dyno sheet for that particular engine showing the horsepower and torque at various RPM points is provided with the engine. Dyno sessions are 4 to 6 hours. They disassemble the oil filter after dyno testing and inspect for debris to ensure that the engine is okay internally. Finally the engine is pressure tested at the crankcase for oil leaks. Below is their web site, I highly recommend them.
Their complete engines are warranted for 12,000 miles or 12 months, whichever comes 1st and they also have extended warranties too.
http://www.cmengines.com
Keep your original engine for number matching needs. Prepare it for longterm storage.
I'm having an engine built by Carolina Machine Engines (CME). I have toured their facility (Johnston, SC) and was very impressed. They are a Production Engine Remanufacture. They spin test the engine with heated break-in oil with the proper additives. The actual dyno sheet for that particular engine showing the horsepower and torque at various RPM points is provided with the engine. Dyno sessions are 4 to 6 hours. They disassemble the oil filter after dyno testing and inspect for debris to ensure that the engine is okay internally. Finally the engine is pressure tested at the crankcase for oil leaks. Below is their web site, I highly recommend them.
Their complete engines are warranted for 12,000 miles or 12 months, whichever comes 1st and they also have extended warranties too.
http://www.cmengines.com
Last edited by 1974CorvetteJimCr; Jul 11, 2013 at 10:08 AM.
Team Owner
Joined: May 2001
Posts: 87,367
Likes: 1,593
From: Western NY
Oils are more advanced, but for the mainstream marked, they lack the proper levels of ZDPP (thanks, EPA), to keep flat tappet cams happy. Secondly, as the market for flat tappet cams shrinks, many of the related parts, such as lifters, are outsourced to foreign manufacturing facilities, which use cheaper grade materials and machining processes.
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Thread Starter
Cruising
Joined: Jul 2013
Posts: 10
Likes: 0
From: El Lago TX
What are possible causes for the lifter surfaces to become concave I should be looking for? Just normal for 95,000 miles? None of the valves are stuck. New lifters slide in/out of the lifter bores with no issues. I would love to go with a crate engine at this point, but not in the budget for the old girl at the moment. Since I am installing the Edelbrock 2101 manifold, someone at Summit recommends going with the Edelbrock 2102 camshaft.
Le Mans Master
Joined: Oct 2006
Posts: 7,123
Likes: 433
From: Gladstone MO
C3 of Year Finalist (appearance mods) 2019
I was working for a Chevy dealer in 1979- we were replacing flat cams then, and some were still under warranty. Appears to me it's been an ongoing problem for a long time, just now with the new EPA regs the oil has changed and it's more frequent.
I'd swap the cam and lifters- perfect chance to step up to a better cam. As others have said- there's going to be metal everywhere.
I'd swap the cam and lifters- perfect chance to step up to a better cam. As others have said- there's going to be metal everywhere.
Team Owner
Joined: May 2001
Posts: 87,367
Likes: 1,593
From: Western NY
I was working for a Chevy dealer in 1979- we were replacing flat cams then, and some were still under warranty. Appears to me it's been an ongoing problem for a long time, just now with the new EPA regs the oil has changed and it's more frequent.
I'd swap the cam and lifters- perfect chance to step up to a better cam. As others have said- there's going to be metal everywhere.
I'd swap the cam and lifters- perfect chance to step up to a better cam. As others have said- there's going to be metal everywhere.
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Before you tear your engine down, remove the oil filter and drain most of the oil out, cut away the outside of the metal can, and stretch out the filter paper to see what it collected. If there is nothing but some very minute particles of metallic "stuff" on the filter paper, you shouldn't worry about significant metal circulating around in your engine {IMO}; the lifter surface just wore so slowly that your filter gobbled almost all of it up. Any of those really tiny particles that got past the filter are either imbedded in the crank bearings (and will cause no real damage) or are caught up in some sludge at the bottom of the oil pan.
If you are really concerned about it, pull a couple of rod bearing caps off the crank and check out the bearing surfaces for any scoring/damage. If none, put them back exactly as they came off.
And, yes, you should change out cam and lifters.
If you are really concerned about it, pull a couple of rod bearing caps off the crank and check out the bearing surfaces for any scoring/damage. If none, put them back exactly as they came off.
And, yes, you should change out cam and lifters.