Cam and lifter advice for an old newbie?

[Maj]

Hiya GMN'ers
Been away for a while but I'm back now and finally started the engine repair job on my '84 Propane burner and looking for advice

I've traced my problem to a collapsed valve lifter.

So here's the thing, I've scraped enough $$ (no work = no dough) together to get a new set of lifters, some assembly lube and the gaskets. Can I get away without putting a new camshaft in? None of the old lifters or the cam are scored and the surfaces look pretty good and smooth. The lifters are very slightly concave but I mean VERY SLIGHTLY.
TBH it needs a new engine but I'm not in that league right now. If it only did another 50K miles on these new lifters I wouldn't have a problem with that. Hopefully by then I'll be back in work and can buy a new motor for it.

Anyone had any success replacing only the lifters? Or am I being an idiot? I know the general rule is "if new lifters then must use new camshaft too" but what are your on the ground in reality experiences?

Thanks guys

[Maj]

:bump: t:smirk:

[P72Ford]

Personally, I would swap the cam and lifters. I have never swapped just the lifters.

Be sure to use break in lube from Comp, or Lucas, etc. Royal Purple also makes a specific break in oil, now.

[Maj]

Thanks P72.
I'm in total agreement, if money were not so tight right now I wouldn't hesitate to replace both. But it is and also this motor needs a full overhaul already so if it will last me a year or so without replacing the camshaft today then I'd be happy

[Tiggie]

Shouldn't be a problem to replace just the lifters. The cam is already broken in so you don't have to worry about it too much. The lifters will crap out again though if you don't run a break in oil.

It really wouldn't hurt to use break in lube on the cam just to help the lifters out some. But that requires pulling the cam out. That means more gaskets and time. This isn't 100% mandatory but I think I would do it if I were in your position.

Buy the absolute best flat tappet lifters you can. Don't go cheap on them. China crap is no good.

[Mercracer]

So here's the thing, I've scraped enough $$ (no work = no dough) together to get a new set of lifters, some assembly lube and the gaskets. Can I get away without putting a new camshaft in? None of the old lifters or the cam are scored and the surfaces look pretty good and smooth. The lifters are very slightly concave but I mean VERY SLIGHTLY.
......Anyone had any success replacing only the lifters? Or am I being an idiot? I know the general rule is "if new lifters then must use new camshaft too" but what are your on the ground in reality experiences?

The "rule" is that lifters must be used on the original lobes only. Once you take them out, if you did not keep track of where they came from then the only place you should put them is in the metal scrap bin. It is not a problem putting new lifters on a used cam.

[gadget73]

Thats what I was always told as well, keep track of the lifters, or replace them. Used cam is generally OK as long as you can visually verify it doesn't look screwed. Shine a flashlight down in the holes. You'll know if the lobes are damaged enough to be a concern.

[sick88tbird]

I strongly believe that new lifters(regardless of new or old cam) need to be broken in properly. You can get some moly lube on the cam lobes with the cam still installed with some patience and a good little brush. 20 minutes with gentle RPM sweeps from 1500-3000rpm to insure the lifters break-in properly...if the lifters don't spin in the bore, they won't last long. Make sure all your pushrods spin with relative ease before putting the valve covers back on...i've seen cheap replacement lifters and rockers not fit the ball ends of the pushrods properly, causing them to not spin. If the pushrods don't turn chances are the lifters won't either.

Good luck,
Don

[87_crown_vic]

an old mechanic buddy of mine used to soak the lifters in oil prior to install then we would install and run a different oil and stuff... it would be changed prior to customer getting car back since they werent the smartest and rarely remembered oil changes and such... did this on a car and got blamed for messing up the car since the car had more power after the repairs and customer messed up driveshaft

[gadget73]

If it made more power after replacing the lifters, it must have been majorly screwed up beforehand.

[Maj]

Hi guys, thanks for all replies, really appreciate the input! I've done as suggested and used a moly assembly lube on all the valve gear contact points including getting some down the lifter holes and onto the can lobes too. I'm doing the final assembly today so keeping fingers and toes crossed the old girl will come back to life!
Cheers

[Maj]

OK, she runs! Hooray! Good to hear it come back to life after over a year sitting.
So now I'm trying to get the tuning setup correct
I've set the timing with my strobe but when I reconnect the vacuum advance pipe from the carb to the distributor it stops dead
Any ideas what I might be doing wrong?
TIA

[johnunit]

was the idle set with the vacuum line unplugged? I doubt the issue with it dying at idle is purely from timing advancing, unless your timing marks are waaaay off.

[sly]

also... check where the vacuum for the advance is coming from. IIRC, it should not be manifold vacuum.