View Full Version : Can't compress new lifters?


Mottley's79
11-10-2010, 06:11:23 PM
I am replacing all the lifters and the intake manifold gaskets in my 1999 4.3 Vortec V6. The lifters started making alot of noise and when I pulled it apart they were either fully or semi collapsed due to sludge. I cleaned one out and the plunger now moves freely. Instead of cleaning all of them, I decided to buy some new ones. They are Mahle Clevite brand, made in USA and I can't compress the plungers by hand at all. Is thnis normal. I need to know 'cause I really need this motor back together! Thanks in advance!

badazz81z28
11-10-2010, 06:19:30 PM
I am replacing all the lifters and the intake manifold gaskets in my 1999 4.3 Vortec V6. The lifters started making alot of noise and when I pulled it apart they were either fully or semi collapsed due to sludge. I cleaned one out and the plunger now moves freely. Instead of cleaning all of them, I decided to buy some new ones. They are Mahle Clevite brand, made in USA and I can't compress the plungers by hand at all. Is thnis normal. I need to know 'cause I really need this motor back together! Thanks in advance!


Are they hydraulic? If they are the right part # and they ALL have this issue, I wouldnt worry, I would really make sure they were the right OEM lifters.

meangreen73
11-10-2010, 06:24:15 PM
On a brand new lifter out of the box u should be able to push the plunger in. When there full of oil and pumped up u shouldnt be able to push them in.

Mottley's79
11-10-2010, 07:03:47 PM
They are hydraulic roller and they are brand new. I checked three or four of them and they were all the same. They look exactly like the old ones that came out.

Louich
11-10-2010, 09:52:48 PM
stick em in and drive on

Damon
11-10-2010, 09:56:55 PM
Agreed. Stick them in and fire it up. The spring that holds the plunger up will take a fair bit of force to overcome by hand, even with no oil in the lifter. When you put them in and crank down on the rocker arm nut they'll compress.

Mottley's79
11-10-2010, 10:25:47 PM
Thanks for all the replies guys. I emailed Mahle and they said it is completely normal. I installed and lubricated the valvetrain and the rocker nut did compress the lifter. Tomorrow first thing, the intake goes on and hopefully I'll be burning fuel before dark!

Louich
11-10-2010, 10:33:50 PM
hopefully I'll be burning fuel before dark!

and tires :)

BondoSpecial
11-10-2010, 11:32:37 PM
I have never been able to compress new or used lifters by hand, they must be pretty hard to compress or I'm just weak.

meangreen73
11-11-2010, 09:24:25 AM
I have never been able to compress new or used lifters by hand, they must be pretty hard to compress or I'm just weak.

when i said by hand i didnt mean literally by pushing it in with my finger. If u take a push rod and stick it in the plunger you can compress a new lifter. I always soak my lifters in oil and pump them up before i put them in

Mottley's79
11-11-2010, 05:21:59 PM
Now, before I start my motor after replacing the lifters and intake manifold gaskets, should I disconnect the coil and turn the motor over for a few seconds before firing it? It is a 1999 CPSFI fuel injected motor.

Mottley's79
11-12-2010, 04:28:31 PM
Started the engine without disconnecting the coil. It was reluctant to start and sounded like junk at first, but after a few mins of idling, it sounds the best it has ever since I've owned it!

Damon
11-12-2010, 04:53:32 PM
It's relearning how to run the engine now that the mechanicals are working properly again. Takes a few minutes and then a few trips around the block at various throttle postions and RPMs. If it takes more than that there's still something amiss.