49 Roadmaster lifter tap question

[Brooklyn Beer]

In the past month I have noticed a lifter starting to tap (hope it is a lifter) that goes away once warmed up.  Coincided with an oil change a week prior. Pretty pronounced this morning after sitting for 8 days. But again went away. This motor has been rebuilt some time ago but no idea when. Hoping they changed over to hydraulic lifters.  Procedure for adjusting before I take the valve cover off?  Should I adjust hot or cold? Best method to isolate the correct lifter? 

[Guest]

It could also be a wrist pin noise.  I have had/heard both but cannot describe the difference from 60 years ago.  At the time I was told that Buick eights were prone to wrist pin noise and it was not worth fixing as it would be back in 10,000 miles.  I hope yours is tappet as that is an easy adjustment.

Good luck.

[Pete Phillips]

Adjust valve lash when engine is warm, not cold. Hydraulic lifters, of course, have no adjustment. You can find out which one it is by listening to each rocker arm through a short section of heater hose or garden hose, held up to your ear. Or, sometimes you can isolate it by simply applying pressure to the spring end of the rocker arm (while engine is idling) and see if the tapping sound changes any. 

[Brooklyn Beer]

Thank you very much. Being it seems to go away when warmed up I am wondering (hoping) if I have a weak lifter pumping up. I have never gotten into a buick motor before and am curious if these early lifters work the same as say a small block chevy lifter?  I did read that early year Roadmasters for 49 got solid lifters and mid year they went to hydraulic. Now I know the motor in my car has been rebuilt at sometime just don't know when. But it is an open port hole car and also read that stopped around the same time they went to hydraulic lifters. True ?

[Ben Bruce aka First Born]

 Buick straight eight lifters are gravity fed from the rocker arm.  Could be just not enough oil flow to the rocker arm shaft or to the one lifter. 

 

  Ben

[Brooklyn Beer]

So Ben if I was to remove the valve cover and watch the valve train would I be able to judge the oil flow by eye? There is no adjustment? It goes away 99% after 5 minutes of running and warm oil

[Matt Harwood]

18 minutes ago, Ben Bruce aka First Born said:

 Buick straight eight lifters are gravity fed from the rocker arm.  Could be just not enough oil flow to the rocker arm shaft or to the one lifter. 

 

  Ben

 

That's interesting. I have one rocker that seems to have oil flooding over the pushrod more than the others. Does that mean the pushrod might be clogged? As long as I have it open, should I pull the pushrod and try to clean it out?

 

Here's a video--watch cylinder #6 (you'll see the oil spill over the side):

 

 

 

Here's more information on adjusting the valves:

 

Edited March 29, 2020 by Matt Harwood (see edit history)

[Ben Bruce aka First Born]

2 hours ago, Brooklyn Beer said:

So Ben if I was to remove the valve cover and watch the valve train would I be able to judge the oil flow by eye? There is no adjustment? It goes away 99% after 5 minutes of running and warm oil

 

 Brooklyn,  maybe, maybe not. I completely dis assembled the rocker arm assembly on mine and cleaned. I ran a  rifle barrel like brush through the main shaft. Cleaned the holes in the shaft that feed each rocker. Ditto on each rocker. They still "look like " they are flowing differently. Did you watch Matts vid?        What MIGHT be apparent is if one [ the one clacking ]  is NOT getting oil.   You do need to determine if your engine does in fact have hydraulic lifters. Probably does, since the noise goes away after a while.  A loose manual one probably would stay noisy.

 

  Ben

[Brooklyn Beer]

I just walked in from the grocery run and will look.  Will take a vid of a cold start for folks to listen too this afternoon and get a starting opinion. Matt are we talking the 49 shop manual?   Matt was that oil spray the noisy one ?  Was something clogged that was not allowing the oil down to the tappet? Mine sounds more to the front.  Ben I am assuming what your talking it is also covered in the manual.

Edited March 29, 2020 by Brooklyn Beer (see edit history)

[Ben Bruce aka First Born]

2 hours ago, Matt Harwood said:

 

That's interesting. I have one rocker that seems to have oil flooding over the pushrod more than the others. Does that mean the pushrod might be clogged? As long as I have it open, should I pull the pushrod and try to clean it out?

 

Here's a video--watch cylinder #6 (you'll see the oil spill over the side):

 

 

 

Here's more information on adjusting the valves:

 

 

 Wow, that sucker is really flowing, Matt.  Since your engine has manual lifters, unless someone sometime changed them,  I don't see any problem with the excess unless it is robbing some other rocker. As I told Brooklyn, even after cleaning mine, they still flow differently.  Actually, in 1950 on the 248, after a certain engine #, the pushrods do not pass any oil. The cup at the top has no hole to allow oil through into the pushrod.

 

    Ben

[Matt Harwood]

I just went out and cleaned the pushrod and even tried to run a small wire down to clear the tube inside, but the wire wouldn't go. I removed another rocker to see if that first pushrod was damaged or blocked, but the one next to it wouldn't take the wire, either. It's possible that it's smaller than the wire I was using (stainless safety wire, which is .041") but maybe they aren't supposed to be open? At any rate, I fired it up again and it was better without as much overflowing. I'm guessing that the hole is like a hair and I cleared it sufficiently for most of the oil to flow through. I'm not too worried about it.

 

 

[Brooklyn Beer]

Well I will remove the valve cover and see what I have.   What was your procedure for just removing one rocker and pushrod?  

[Matt Harwood]

I guess I shouldn't have said "removed." I just loosened it enough to get access to the pushrod cup. The pushrods aren't coming out without the whole rocker assembly being removed and I wasn't up for that.

[gdmn852]

Hello, only about 5,000 early 49.s were solid lifters, Without hearing it sounds like a lifter ,they will click at start up until oil pumps up in them,If you take off the valve cover  you may be able to see the lifters and check .Before taking engine apart you may just want to drive it and see if it gets worse or goes away.The 1948 49 Manual goes over the. Valve train well . Also as I. Found out from experience there are different cams between solid and mechanical lifters also the upper arms .There is a small hole in the brass fitting to the upper valve train,the oil flow Is restricted to them also a small screen inside the fitting.So the oil flow isn’t high pressure. Could check it as mentioned in one of the above posts I bought a cheap stethoscope from Harbor Freight that comes in handy.

[gdmn852]

Hello again on early 49 s they will have the open ventiports with hoses connected to the inner fenders I think 3 inch in diameter if I remember correctly,also there will be two ID plates, one on top of cowl near data plate and one on drivers side door post ,the Dynaflow dipstick will be under passenger side floor mat ,on later models it was relocated under the hood. I also believe that the bearings were changed to insert type the same time hydraulic lifters were installed.They due have a tendency to leak out when sitting for a while, I had a Chevrolet Suburban that would rattle on Ist startup of the day my young son asked me why it made that noise, I said it was letting me know it was running 😉