What are the chances of a 66 Vet engine NOT being machined for hydraulic lifters? I just put in a second set of lifters (hyd) and by adjusting them by the book the car will not run. If I back them off about a turn, leaving them at about the clearance of solid lifters the car runs fine although with typical solid lifter ticky-tick. The original lifters that came with the engine (bought used) did the same thing and also the first replacement set. This motor has been decked so there is no code on the front boss. The cam seems very mild and will idle relatively smooth at 500. Ideas??? Bob

 

Well it is eather machined correctly or it is not. I don't think there is any difference between machining operations for mech and hydraulic lifters. If the engine is OK for solids it is OK for hydraulics. If it is OK for hydraulics it is OK for solids.

To diagnose this I think more data is needed. What caused the first set of replacement lifters to go in? Do you KNOW what type of cam is in the engine? It is not unheard of to have solids on a hydraulic cam or hydraulics on a solid cam. Neither combo orks for long but people have been known to do it. We need to know what stated the lifter swapping festival and we need some data about what is inside that motor.

Did you put the cam in yourself or did you just buy the car with the engine the way it was then start swapping lifters?? Data like that is necessary before you can get to the bottom of this, Might be the cam is trashed and a replacement is needed ...more data requested please.

Just a post script here. I had a 400 ci SBC once. Got it in the junk yard for $150 and everything looked perfect I mean PERFECT. I found out that one lifter bore was machined oversize. There was no way on earth to quiet those lifters (hydraulic) after the motor warmed up. Oil circulates from lifter to lifter and once the loose bore expanded a little none of the downstream lifters got enough oil. Everything was cool until the oil temp and block temp got up to operational ranges. I think the motor was a warranty take out...Chevy dealers usually rendered the take outs unuseable by cracking off a boos or something but I bet this motor was grabbed by someone in the dealership and later found its way to the boneyard without ever running. I repaired the bad bore by machining it out a pressing a sleeve in ....the engine ran perfectly for many miles after that.

 

Oman, I know where you're coming from. Twenty years ago I put a set of hydraulic lifters over a solid cam and wore out the lobes in ten miles. (VERY stiff valve springs). Back to my problem, don't know what kind of cam is in the car- came with the motor but idles too smoothly to be a solid cam IMHO. Originally when I bought this motor it ran like Sxxx but I was desperate. That caused the first lifter change- got the motor to run good but if I cranked the adjustment down to spec wouldn't run at all. Ran it this way for 2 or 3 thousand miles. Only reason for the latest change is I broke a pushrod and since it was apart thought I'd try a new set of lifters figuring maybe I got a few bad ones in the previous set. About the machining, I know the lifter bores are the same I thought maybe there are oil passages leading to the lifters that were not necessary in a solid set-up and perhaps left out in solid applications. Any specific questions I can answer to help, send them along. Bob


[Modified by claf, 11:53 AM 8/16/2003]

 

Your still not giving me much to go on. Would not wanna be your doctor. I guess we would have to start with "The Spec". Are you going a 1/4 or 1/2 turn past where the ticking stops? Eather of those should work on a stock motor. Hell even a full turn should be OK.

What do you think the motor is? 300HP / 250HP / 350HP / Crate motor? What do you know about this motor and its history? Are you saying it just plain dies or that it just won't run well after the adjustment? Does just one lifter kill the motor and if so is it the same one all the time? OR as you adjust more and more lifters does the engine slowly sucumb a little more to each additional adjusted lifter till it finally dies? How does it die? Does it pop out the cab? Does it pop out the exhaust? I can't imagine it just idles down and stops but I suppose even that is possible.

Honestly I suspect that something is hosed in the cam / valve gear or there is a mismatch of parts. I can't buy that it is the lifters after two sets did the same thing. Just does not make sense. Excluding the pushrods cause they are failrly dumb parts (that is assuming that they are the correct parts and they are not bent) then it has to be eather the cam itself or possibly the springs are toast. Are you sure the timing chain is OK? If it is toast ya might need the extra looseness in the valve adjustment to compensate for the slack in the chain. Again I am just fishin here but w/o some of the data I asked for that is the best I can do.

Assume the engine is ticking cause you have the lifters backed out enough to make noise and to allow the engine to run. (Remember I need a definition of what you mean by "donesn't run" but assuming it IS running and ticking. Does it drive OK and seem to have power? Does it rev to a reasonable amount of RPM?

How did you wreck the pushrod? I think some data wrapped up in that event is important. Were you pushin the engine up to high RPM? Did it just start coughing as you were driving along? Something tells me the push rod failure is linked to this somehow. If the cam is bad and has a few bad lobes and ya reved the snot out of the motor....pow bad pushrod.Easy to imagine that happening. It would seem though that a bad lobe(s) would make it necessary to sock the lifters even tighter to shut the engine up and stop the ticking. It just sounds cam related: it is not the lifters not after two sets...no way.


[Modified by TheOman, 2:34 PM 8/16/2003]


[Modified by TheOman, 2:40 PM 8/16/2003]

 

claf, I had the same exact problem with the 350 that was in my car when I got it. I didn't have any history because my car was underwater and I purchased it from the insurance company.
When I got the car running the lifters where ticking so I started to adjust them as solids, but I soon noticed that I could push down on some lifters. So I adjusted them as hydrualics and the engine barely ran. So I adjusted them at .008" and the engine ran excellent.
I changed the lifters thinking maybe from the water some lifters where frozen.
Same thing. So I thought maybe the springs where weak and not bleeding the lifters. I replaced the springs and the same thing. Of course everyone I talked to said they never heard of it including tech people at Federal Mogul.
I used this engine for well over a year adjusted at .008" and never had a bit of trouble with it. I finally sold it and put the correct 283 in the car with the same Federal Mogul lifters and they work properly.
I know this doesn't help you but when I had this problem I called and talked to just about everyone in the know and still no one has a logiclal explanation for me.
I would be real curious to know the answer.

 

Thanks Plaidside, I was starting to think that I've done something radically wrong with this engine. Now there are two of us that have had an unsolveable problem. OK, back to TheOman. With the engine off I adjusted the lifters to zero clearance, no extraa 1/4, 1/2 or full turn tighter. The engine would fire up and after a few seconds would run progressively worse until it would stall and not restart! Some noise thru the carb, almost like the valves were hanging open. All the lifters seem to act the same way- they all tick. This was sold to me as a 300HP by a guy I knew from work. His story was that he was going to put a correct 283 into his 59 so the 327 was available. When I open up the clearances the motor runs GREAT. I can't buy into the cam or valves being bad. Compression is 185 across the board. I broke the pushrod when I jumped on it in 4th at fairly low RPM. I heard a couple of solid pings and the motor went into seven cylinder mode. When I had the head off that side NO marks on the piston or the valves indicating they never hit. My guess is that the rockers were soooo loose that the pushrod slipped out of the pocket. Maybe I should have spent the extra bucks and bought Chevy parts and not NAPA??? Bob


[Modified by claf, 1:10 AM 8/17/2003]

 

Might be we are getting somewhere here but I still am stuck on the fact that 2 sets of lifters had this problem. I agree with you on the demise of the pudhrod. Likely things were so loose that it just lost the rocker and good by pushrod.

This starts to sound like my engine with the bad lifter bore. It ran fine for a few seconds. A minute or so actually then the oil thinned out and the lifters bled down then the engine would quit.. If I shut the engine down and pulled a valve cover the rockers farthest away from the bad hole lifter bore were almost falling off loose. Makes me think about your pushrod. See where I am going?

Could there be an oil pressure / distribution problem with this motor? A plugged galley? Did this engine ever get grenaded to the point there might be debris in the galleys feeding the cam / lifters? There are oil gallery plugs that if left out (or if they fall out) result in a huge internal oil leak. The oil never gets to all the lifters and the pushrods. It just sort of internally hemorages ...you see no oil on the floor but in effect there is no oil or very littlle oil getting up top past the lifters. Just a theory.

I would run the motor with the valve covers off AFTER adjusting the valves for minimum noise. Watch the oil supply at the rockers. If it sort of tapers off before the engine dies or if it is uneven in flow volume from valve to valve ...PARTICULARLY if it is OK up to one particular valve but weak or non existant beyond that valve then we are really making progress.This likely will make a mess but throwing parts at it ain't the way to go. Ya gotta see what is happening when the motor quits.

Has this engine recently been apart? Are you sure it has the right cam? You mention the former owner messing around with 283's. Some older SBC cams for 265 CI engines had a notch in the rear journal. If used in the newer engines all sorts of funny oiling problems result in the valve train. You mention that this motor will idle at 500 RPM. The 300 HP cam is a very docile thing but some of the older SBC cams are even more docile. Just an outside theory but ya never know what some "enthusiast' who has no idea what he is doing might swap into an engine. The 265 cam will physically fit so it is a possibility. Ya gotta pull the cam to determine if this is the case so hang on for now as far as that is concerned.

 

Another variable in lifter oiling is the distributor; the machined boss at the bottom of the housing seals off the oil galleries to pressurize the passages that feed the lifters. If there's some sort of odd-ball distributor in there without the correctly-machined bosses at the bottom, that could be contributing to the problem.

If the distributor configuration is OK, I'd trash the cam and lifters and start over again with a known matched cam and lifter set, since you don't know what cam is in there or what shape the lobes are in. :thumbs:

 

ahhh.
adjusting by "the book"
i've seen some books say to twist the pushrod until you feel resistance.
Is that the book you are using?

i use the "up and down" method:
pull the pushrod up and let it drop down, tighten until no up and down play, plus 3/4 turn.

 

Some answers, some questions. To JohnZ, I'm using a stock tach drive distributor so not much chance of that being the cause. To Matt, I adjusted the lifters by tightening down 'til I felt the push rod starting to snug up while rotating it. Ultimately have the car running by adjusting ALL the lifters one turn LOOSE. To Oman, Engine has definitely been apart but not by the guy I bought it from, as the ident pad has been machined off. Can't tell much about the engine as I bought it as a long block- no manifolds, carb, WP or dist. I did get hear it run, it ran lousy but had good oil pressure and didn't make any "funny" noises. First thing I did after getting it in the car, before starting it up, was to change the spin on oil filter to the older canister type as this motor is in a '62. When it started up the oil pressure was off the gauge I don't know what I did wrong but I don't think you can put those canister adapters on incorrectly. I attributed that surge of 100 lbs of oil pressure with blowing out the original lifters. Started the engine several times waiting for the pressure to go down but it never did. Finally took the adapter off and rotated it 180 o's and put it back up and the oil pressure came back to "normal". Right now it runs at 30/35 and 15 at idle. Bob

 

this is a very common problem. i tried the twist method, but i was suspicious, and checked the lifter, and sure enough, the plunger was bottomed out! :eek:
that's when i switched to the up and down method :cool:
The good news is there is no serious problem!
some lifters have a very light spring, making the twist method a bad method

 

I am wondering if the surge of oil pressure blew out one of the oil galley plugs ?????

When I talk about what happens inside a hydraulic lifter I get on thin ice so somebody might have better data than me. Instead of theorizing I am going to ask a question about the lifters.....what is the effect of backing a hydraulic lifter all the way out to plus one turn? How does that backing out of the plunger on the lifter relate to engine oil pressure supplied thru the galleys? Or said differently...if the oil pressure in the galleys is too high or too low what is the effect of tightening the lifters down?

See where I am headed? It ain't the lifters 2 sets proved that. Now we know about the oil pressure surge. You must have had high pressure at the back of the engine cause that is where the SBC oil pressure is measured. Backing out those lifters someohow compensates for some kind of abnormal condition in your engine. If there is a relationship between the lifter plunger position and oil supply perhaps we learn something. I just don't know enough about the goings on inside the oil system. It could be that the cam is just junk and has flat lobes but that does not make sens. Loosening a lifter on an already flat lobe(s) is NOT gonna help the engine run better.

Can't believe that the pressure surge trashed the lifters...also I had a GTO that has the same lifters as a SBC uses. That thing burried the 100 lb guage in the winter when the motor was cold so that tells me the lifters can stand 100 PSI.

I am kinda with John Z on this ...junk the cam and lifters and start clean with new stuff. On the other side of that coin I like to get to the bottom of stuff like this. It has to be the cam or the supply of oil to the galleys.

Any other data bombshells like the 100 lb oil pressure issue after the canister change????? This has to be oil pressure / oil supply related.


[Modified by TheOman, 1:19 PM 8/18/2003]

 

I know it was not my distributor because I am using the same one in my 283 and have had no problems.
As far as the spinning push rod method, I have been using it since the 60's without any problem what so ever. The only time I had a problem is with the 350 in my Vette.
I had a long conversation with the tech people at Federal Mogul and they had no ideas as to what could be the cause. I would have tore the engine apart but I sold it.
I would love to know what could cause this problem.

 

update?
this comes up so often on c3's.....
Some people can pick up a book and do brain surgery, others need training.......
plaidside
i used to use the twist method(YES IT DID WORK) until i noticed the soft springs in the late 1980's. And if you have a very light touch, it still works :cool:


[Modified by Matt Gruber, 4:23 PM 8/19/2003]

 

I want to thank all the people who tried to help me out with my little problem. Originally I thought someone would have had the same problem and could give me a step by step solution on how to fix it. No such luck. At this point due partly to the short cruise season here in Massachusetts I'm going to leave things alone at least until fall. I drove the car 90 miles last night with absolutely no problems EXCEPT the noise. Rather then throw dollars and parts at it, I will, eventually, attempt to tighten down the lifters in VERY small increments and possibly sneak up on the ticking until it's gone or minimized. If I ever do come up with the cause or solution I will post it for the enlightenment of everyone. Probably the only way this will get fixed right is if something else breaks seriously and the engine needs a total rebuild, otherwise, tick,tick,tick,tick. Thanks, Bob

 

i always make the final adjustment with the engine running.
:smash:

 

I've been waiting for you to reply to the question of "are you getting oil squirting out of your rockers". I may have missed it but I don't see the answer. If you're not getting oil to the rockers/push rods your lifters are collapsed and that's why you cannot adjust them with a turn down after they quit clicking.

 

MikeM, sorry for dragging my feet. Popped the valve covers off this morning and, yes, I have a good supply of oil to all the rockers. How about another possibility. Although I mentioned earlier how smoothly and slowly it idled, today when I checked the lifters ( one turn loose, from "no play") I found the clearance approximately .100 ! I then turned the rocker nuts down a quarter of a turn- as I said I'm trying to sneak up on this thing. Now the idle is somehat rougher. Is it possible that I DO have a performance solid lifter cam in the motor and the reason it ran so smooth previously was because with the lifters backed off so much the valves were actually opening later, closing sooner and not opening as much ???? At any rate I put 300 miles on it with the .100 clearance with no ill effects, this week I'll drive another 2 or 3 hundred and if all goes well , I'll take them down another quarter turn. Bob

 

Bob:

I didn't mean to sound impatient.

It is possible you have solid lifters but I don't know any of them that are set at .100. If it were mine, I would work the clearance down to around .030 and see how it runs. You should hear noise from solids but there should be no clicking sounds. Hard to describe the sound but when you get the lifters adjusted right, they will not make objectionable noise for most people. You can hear it, but not objectionable.

I have from time to time, taken the heel of my hand and shoved down on a rocker on a running engine (with hydraulic lifters) and temporarily collapsed the lifter enough to make it momentarily clatter until it self adjusted. You might try this.

Otherwise, take previous suggestions and replace the cam and lifters so you will know what you have in the engine. I would not continue to run it with .100 valve clearance. That's gotta' be causing all kinds of valvetrain wear.

Mike

 

when you adjust it properly, engine running, it is normal for it to run rough for a few seconds as you go + 1 turn. it can be tuned in 1/8, 1/16 or 1/32 of a turn.
your .100 sure sounds like full plunger depth plus just enough for a tick. :lurk: :nopity