WOW !!!! That thing is clean ..... OK now I know what mine should look like ....... And there is no varnish ??? Does that mean mine overheats (and thus cooks and deposits varnish) ?
I'm gonna disagree with a few of you folks. I bought a '76 Olds Cutlass that had a bad lifter tick. I pulled the valve covers off and what I saw made your Nailhead look clean. I replaced a pushrod, a rocker stand, and two rocker arms. I scraped what sludge I could out of the rocker area and dug out the oil return holes. I warmed the engine and changed the oil with 10W30 high detergent. I ran the car and repeated the oil changes at 500 mile intervals. The oil consumption gradually dropped from a quart in 500 miles to 0. I wore out the '76 Cutlass and installed the engine and THM400 in an '81 Olds wagon. When I finally sold the wagon for $200 (12 years later), the 350 Olds engine had 323,000 documented miles on it. It was quiet and just beginning to use a little oil. I replaced the timing chain and gears as PM at 212,000 miles. I never had the intake manifold, heads, or oil pan off of it. You want to move the sludge in your Nailhead to the oil filter. That's what the full flow oil filter is for. BTW: Nailhead lifters are flat-bottomed and don't spin.
All good knowledge/experiences. I've done the diesel fuel flush a couple times and it worked out OK. As I recall, I filled/drained 2-3 times, changing filters each time-and never running with any load. I've also pulled apart a few nails where the lifter bottoms were 'peened' over a bit and used a dremel to take off that edge to remove out the top. Got to be tough working on these overseas with no parts/support-
Yes its really hard here to even find the most basic US bolt !!!! Makes things a little harder I'm going to try to remove my hydraulic lifters tomorrow that dont want to move due to varnish.... Will try acetone or paint remover to loosen them.
If you are going to remove the lifters - I would recommend that you have a new set ready to install. I suspect that when you get a look at the lifter bases, you won't want to put them back. I go along with Tom T. 100%. Either put the thing back together as it is, or do the overhaul now. Just my opinion.
This is real good advise. If you do pull the lifters and find they are badly cupped on the bottom it will be hard to justify putting new lifters back on a bad cam. Was there a specific problem that led you to pull the top off to begin with. If so try to address that. If not put it back and figure it will run untill you can do it right. When you start into it there is no good stopping point.
If you take the lifters out, make double sure that you put them back on the same cam lobe that you took them from.... if you dont, it will instantly destroy the cam when you start the engine again.....:Smarty:
Doc`s comment adds justification to Tom T`s opinion, my opinion and others...put it back together until the time is right to do the job properly or you`ll likely do more harm than good. :idea2: Tom Mooney
I know.. you are right... better not to mess with things... but I have a question: how do I know if they are operating correctly ? Can they be full of varnish and not working as well ? Do they need dismantling and a thorough cleaning ? May be stupid questions but they itch me !!
I should post some pictures from when we rebuilt my fathers engine. It would put yours to shame in terms of how much sludge was in that thing.
a lifter can work properly with a lot of sludge around it.... if it was not noisy then it was working ok.... at this stage , I would loosen and shop vac all of it i could out.... and then put the engine back together and plan and put your efforts toward a rebuild.... if you rebuild soon it will not be near as expensive....
I finally got all the lifters out. And I just dismantled one. It was hard to get it apart .... lots of crud in it kept it from dismantling freely. This is one of the worst looking ones.. They all seem shiny (& greasy) on the lobe surface.... I thought they looked great until i took a close up picture ! With the digital camera up close they look worse. You will tell me they are probably in good shape....or not ! I am not an expert so I cant tell...
Pictures of the lifters shown. THEY ARE BAD!!!!!! At this point ALL should be replaced!!!!! The bottoms are supposed to be FLAT!!!!
. . . AND SMOOTH TOO! Wow do those ever look terrible. I'm guessing that engine has NEVER been apart.
Oh !! Well new lifters it is. I noticed 2 types: TA Performance: TA_1406 at 79$ .... it is for a set ? of 8 or 16 ? It cant be for 1 SEALED POWER Part # HT896 I dont have to change the CAM do I ? Why would they be worn ? Are they being properly lubricated ? Need to clean some type of oil port or something like that before reassembly ?
Yep, the lifters are definitly gone... and I am betting the cam too....and the timing gears and chain,,,, just as well pull the engine and go thru it.....
I hate to say "I told you so," But a lot of us have been there and done that. Doc and Tom are both right. The lifters are junk. I would take a very hard look at the cam. If the cam is bad, there's probably a lot of other stuff that isn't far behind. You are pretty much at your last stopping point. You can install a new set of lifters, put it back together and drive it for a while - or yank the engine and start the rebuild. Practically everything you will take out of that engine will show wear. When my 425 was rebuilt, when all was said and done, we were able to rescue the block, timing case, water manifold, crank, rods, heads, some head bolts, and the valley cover. Everything (and I do mean everything) else was replaced. I would guess that on a 40 + year-old engine, this would be about typical. Unless you are prepared to spend a lot of Euros; I would not disassemble it any further right now. Just one old geezer's opinion.
After seeing that last closeup photo of the worn camshaft lobes and the wear pattern of the lifters, I can't see how that cam could survive a break-in with new lifters...chances are slim to none, in my opinion. Devon
The lifters are worn for several reasons. 1. The contact between the lifter and cam is the highest-pressure sliding contact in the engine. 2. The engine most likely has quite a lot of kilometers on it. 3. At least in the USA, many modern oils do not contain enough zinc for flat-tappet engines. You must add ZDDP to the oil, or use an oil known to have plenty of Zinc in it. Most modern engines use roller lifters and don't need the Zinc. 4. Many (if not all) Buick Nailhead factory cams are forged, not cast. The cams stand up well, but are tougher on lifters then a cast-iron cam would be. 5. Buick lifters have flat, not convex bases. They are not designed to spin in their bores like many other pushrod engines. Those lifters are about average for a normally-driven, high-kilometer Nailhead. Hope this helps.
