1 (edited by SpaceFrank 2017-04-20 10:29 AM)

Topic: Comment on my Crappy Camshaft Concerns.

Bob and I recently rebuilt a 225 slant six that came out of a car whose previous owner didn't know about oil changes. So much black gunk in that block. We stripped it down, cleaned it up real good, measured all the bores and journals, and decided it didn't need actual machine work. So we reamed the ridges, honed the bores, and put it all back together with new rings, crank bearings, and cam bearings. The camshaft itself looked pretty worn; I think the tip of each lobe had lost 030-.040" lift. But the engine was going in an art car, and it had run when parked, so we figured it was good enough for the power this engine needed to make. The old lifters had to be pounded out of the block with a screwdriver, so we replaced them with new.

On initial startup, everything was fine. Good oil pressure, and once it got up to temp and I got the valves lashed correctly, it purred like a kitten. Only one problem: most of the pushrods (and therefore the lifters) aren't spinning. My online reading tells me that this will lead to "premature cam and lifter wear." Well, the cam is already pretty worn. We went ahead and did a normal cam break-in for the new lifters, but no change. The car drives perfectly, in my opinion. If I hadn't checked for lifter spin, I wouldn't suspect a problem just based on performance.

Should I be concerned about this? Is the cam going to get much worse than it already is just because the lifters aren't spinning? I don't want to sell this car as-is if the freshly rebuilt engine is going to crap out on the new owner. An in-car cam swap would be a pain in the ass, but it wouldn't actually be as bad as on most engines. For an early slant six, you don't even need to pull the head. Hardest part would be jacking the engine up to get the oil pump off.

Command Pilot/Flight Director, Escape Velocity Racing
Index of Effluency, Heroic Fix, Class C Trophy, now hopelessly gunning for Class B.
Currently 1-2 vs. Team Fairlylame in the Class of 1964 Championships

Re: Comment on my Crappy Camshaft Concerns.

IIRC, cam lobes are slightly 'tilted' so that one side of the lifter gets slightly more pressure than the other and therefore spins the lifter.  If you already have cam wear and that 'tilting' is gone, then yeah the engine is going to spin itself to an early grave.  Only way to fix is with a new cam.

--Rob Leone Schumacher Taxi Service
We won the IOE at Southern Discomfort.
We got screwed at The Real Hoopties of New Jersey  and we took cars down with us.
We got the curse at Capitol Offense but they wouldn't let us destroy the car.

Re: Comment on my Crappy Camshaft Concerns.

It's a slant six.  An "early grave" for this engine could be 50,000 miles from now.

2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?

Re: Comment on my Crappy Camshaft Concerns.

Another thing I'm realizing we probably should have done is hone the lifter bores. That might be a thing to try first if any of the lifters prove difficult to remove.

Command Pilot/Flight Director, Escape Velocity Racing
Index of Effluency, Heroic Fix, Class C Trophy, now hopelessly gunning for Class B.
Currently 1-2 vs. Team Fairlylame in the Class of 1964 Championships

Re: Comment on my Crappy Camshaft Concerns.

For the Opel, and it might be the same for your engine, that new lifters, even on an old cam, need to be "run in". For our engine that means as soon as we get the engine running we need to rev it to 2000+ for about 20 minutes. We need 2000+ to get the lifters to rotate.

Mike

Re: Comment on my Crappy Camshaft Concerns.

SpaceFrank wrote:

Another thing I'm realizing we probably should have done is hone the lifter bores. That might be a thing to try first if any of the lifters prove difficult to remove.

Yes, this.  I've even just run a soft-bristle wheel on a dremel tool in the lifter bores to clean them up when doing a quickie-refresh.  Get them lifter bores nice and shiny.

2008- 2010:  1966 Volvo 122, "Charlie"
2010-present:  1975 Ford LTD Landau...doesn't have a name?

Re: Comment on my Crappy Camshaft Concerns.

If the lifter lobes were so worn that you lost .030 lift than that cam is junk!  You will never get the lifters to rotate since the "slope" ground into the cam when new is long gone!  GET A NEW CAM!

You can buy a new OEM replacement for under $100 delivered!

Re: Comment on my Crappy Camshaft Concerns.

Check the new lifters as well, they may be hurt.

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