Itinerant Air-Cooled

The new hydraulic lifters in my rebuilt engine are failing at an alarming rate due to the internal spring breaking. I replaced the first lifter that broke with a new one thinking it was a fluke. Three more broke after that. I have "fixed" them by stretching out one of the pieces of the broken spring to near the original length, bench-bleeding and reinstalling.
Another one collapsed last night - not sure yet if it's one I fixed or another spring breakage.

My engine builder is ordering a whole new set of lifters for me (no charge), but I'm considering keeping them in the box until the end of the summer when I'd like to split the engine to get the stupid "torque special" cam out of there and replace it with stock.

Can I remove the spring from a hydraulic lifter so it will always be fully collapsed and run it like a solid lifter, adjusting the valves for .006" clearance? Without the spring, I would think there is no way it could pump up. I guess I could remove the check ball to be absolutely sure.

Thoughts?

What do you not like about the cam?

- Doesn't idle nicely, really bad when the engine is cold.
- Has no bottom end at all coming off idle (I modified the dizzy for more initial advance to help in this regard.)
- No noticeable power increase
- Is not recommended for FI engines, which is what I have (long story)

If your hydro lifters are failing, then most of the symptoms you describe would relate to lifter problems and not the cam. If you do not want to install the new hydro lifters to confirm this, pick up a set of solid lifters and install them instead. Yep, you will have to do valve adjustments but they will work better than trying to make a hydro lifter work like a solid.

It ran the same when the lifters were originally installed with the new cam and were all pumped up and happy. They have less than 500 miles on them.

I want a stock cam back in, but don't want to pull the engine until the end of the summer.

My understanding is that solid lifters require different pushrods and rocker arms than hydraulic, so I'm not sure I can do that. Plus, I want to avoid the cost of buying any new lifters.

busman78 wrote: pick up a set of solid lifters and install them instead.

You may not install solid lifters on a hydraulic cam. The ramp profile is more aggressive and you will seriously breach the oil film between the lifter and cam due to extreme edge loading.
Colin

Done it several times, once for over 44K miles with no damage. Granted the power curve was off, it ran, got good gas mileage but a bit weak on a steep climb (required down shifting). This is not something I prefer doing, but if a person does not want to tear the engine down right away or try new hydro lifters then this is a better option than trying to run punched out hydro lifters. I no longer will even consider a hydro cam for a VW AC engine, learned my lesson many years ago.

Yes the pushrods do need to be changed. Rockers can stay the same.

vwlover77, consider a Raby 9550 cam, consider something, consider anything but stock.

busman78 wrote:
vwlover77, consider a Raby 9550 cam, consider something, consider anything but stock.

=D> =D> =D>