Think I have a problem with collapsed lifters. I know the heads have to come off but how difficult of a job is this? Any tips or advice? Read up on removing the heads and that seems reasonable. Do the lifters just drop in?

 

Pretty simple man . The lifter's have holder's that will need to be remove and then you can use a pen magnet to pull them out . You may want to replace the holders at the same time as you do the lifter's . Make sure you pre-soak the lifter to pre load them before install .

Link:
http://www.ls1howto.com/index.php?article=1

Thx
Manny@E.C.P

 

Depending on how much time you have, the job will probably take you two days. Make sure you have the manual and all needed tools, parts and so on before you take it apart. Its not as bad as you might think but depending on the year of your car and so on, will make the difference. For example, I had a bad time trying to get the power steering pump pulley off my '99 because it didn't have any holes in the pulley itself. Make sure you buy a full set of new head bolts for both heads and if not already having loctite on them, buy some. One thing to remember when you go to reassemble, suck out any and all coolant from the headbolt holes BEFORE you put those heads back on. That's very important! Make sure you precisely follow the manual's instructions on re-torquing the heads. The new headbolts you must use are called something like stretch to torque. For mine, the EBTCM was a pain as well. I ended up removing it and using small corks to plug up the lines. Others in here might have a better idea or other method to get it out of the way, if needed on yours. Before you put it back together, make sure your head and cylinder surfaces are absolutely clean. Don't chance any sloppy work. You will have removed the oil and coolant during the teardown. The coolant you can put back in but not the oil. When you get it restarted, heat it up briefly, then change the oil again as a personal suggestion. Then do it again in a day or two...those first two loads of oil, I would use cheaper stuff but its up to you. Lots of work but you can do it properly. Remember, you are doing the exact same thing a dealer would do.

 

The Head bolts are Torque to Yield and should not be re-used. You might as well replace them with studs as long as you have the heads off.

 

Thanks for the tips. That link helps.

I'm in no rush. It can take 2 days or 2 weeks. I just want to make sure I get it right.

Any recommendations on what kind of lifter to use? It's a H/C ls1. 430rwhp shifting at 6.7k. Will ls7's meet my needs?

 

LS7's will be fine....but if Fartpipe gives you his wifes credit card you could upgrade to Morels!

 

I have had great luck with the LS7/LS2 lifter. I have used them in four different builds (all w/demonic camshafts). I have about 5,000 miles on my current build (using LS7/LS2 lifters) with a custom grind (.655"/.611" & 235/241 @ 111LSA).

 

LS7 lifters == LS2 lifters.

Some people also like the caddy raciing lifters, not sure if they are the same as LS2/LS7 or not.

Make sure you get new lifter trays as well. You need 4 and they come in boxes of 5.

Each Tray holds 4 lifters or 2 cylinders worth.

Sometimes the sound you hear is not a collapsed lifter but "play" between the lifter and lifter tray.

FWIW, I put 243 heads on my H/C 1997 Vette and replaced the lifters. No difference in sound. The new lifters did look beefier though. 243 heads were also nice.

If you don't have headers and want them, now's the time. With the heads off they area breeze. Good time for LS6 intake swap too.

The heads are not a bad job except for the ground wire on the back of the head and the air pump stuff running behind the head.

All the stuff you can see and normally think of comes off easily. It's the stuff you can't see/don't think of that sucks.

 

I just did my heads, it wasn't hard, just time consuming. It was 27 degrees in my garage for the most part.

 

The LS1/LS6/LS2/LS7 lifters are all the same at this point... Can be had for $120 a set.

 

Nick Check this thread of OhioC5 :

http://forums.corvetteforum.com/c5-t...head-swap.html

Gl man and if u r ordering gasket kit or Lifters let me know we both can order same time.

 

I have a question for the OP. How did you come to the determination about the lifters collapsing? I replaced mine after one or two failed, but that was at 274K miles and I'm guessing you aren't anywhere near that high in miles? Have you pulled the valve covers to look for a broken valve spring? Compression tests?

 

Removed valve covers and checked springs, rockers, and pushrods. They all checked out. I will be doing a compression test soon. I have 70k on the car now and a few of those miles are hard/track miles. The only thing left on the top end is lifters.

The sound is a metallic tapping noise that sounds like its coming from uo top.

 

Typically when lifters start to fail, they'll have tapping sounds till they pressurize or begin to heat up which happens later in the failing process. If your's are tapping briefly, then you are probably correct. If they don't stop tapping, I will imagine the clattering is pretty bad. With your description of the hard track miles, I'm sort of wondering if you've got a slightly bent valve stem?

 

I am doing a compression test tomorrow. If it is a bent valve stem that should show in the compression test, right?

As soon as I heard the tapping I shut the car down and have not started it again. So I don't know if the tapping will go away when they heat up. We will see what a compression test shows tomorrow.

Either bent valve or lifter the heads are going to have to come off.

 

Compression test is very simple to do. You may want to do a leakdown to see where the motor itself stands. This will also help isolate the problem if you do indeed have low compression numbers on certain cylinders.

Good luck bro

 

Yes, agreed, the heads still have to come off. May I ask, what was the condition of the engine at the time the clattering started? Was this a sudden change?

 

Yes it was a sudden change. I did a burnout and as I rolled out of the burnout it was making this noise....................

http://www.youtube.com/watch?v=U-S69H_RB0k

I shut it down and had it towed home. The sound in the video does not sound exactly like what it sounds like under the hood. Its a metal tapping noise. Already pulled valve covers and checked rockers, springs, pushrods so the only things left on the top end are lifters and valves.

Motor as 70k on it. H/C installed at 55k. Lifters are stock and valves were new with the H/C setup.

 

That video sounds bad. Sure hope it's just a lifter. Good luck.

 

compression test done. it came back really good. results are posted in my thread. if anyones interested in reading as i try and pin this problem down....


http://forums.corvetteforum.com/perf...or-report.html