Remember keep it simple, old school run a quart of ATF in it go for a ride and change oil, or just run an additive in it, take it to the Bash and change oil when you get home. Remember KIS.

Typically if it's as you describe it is lifters that have bled down while sitting and it is taking the normal time to fill the lifters back up. I seem to think your car sits for quit awhile so it is a normal situation just like a Lycoming.

Flat tappet or roller cam?  Mobil 1 doesn't have the proper additives for a flat tappet cam and I'd hate for that clatter to be an indication that you are losing a cam lobe.  My engine guy tells me that with the latest API spec oils, even the zinc additives are less effective.  If you do have a flat tappet cam you may want to pull the valve covers and check for any rockers that appear to be loose (check them as if setting valve lash by rotating the crank).  Don't want to be an alarmist but you never know.

Here's a link to the full Mobil chart -

https://mobiloil.com/~/media/amer/us/pvl/files/pdfs/mobil-1-oil-product-specs-guide.pdf

It does look like the 15W-50 has enough zinc if you are comfortable running that high of viscosity and if the cam isn't damaged.

I'm running "DRIVEN" HR5 10-40 oil in the 390 that's in my truck.  Don't want to start a motor oil debate - just wanting to make sure that your cam hasn't been damaged.

To get rid of the clatter you may just need more viscosity.  A 15-40 or 50 may do the trick.  Some older engines don't necessarily like synthetics so you might try a traditional high-zinc oil and see if your lifters are happier.  Again, this is not an oil debate...

I guess if a higher viscosity makes things quiet you might be OK but I would check the rockers for excessive lash just to be safe before heading out on a long trip.  Just the retentive side in me coming out.



 

If it eventually quiets down the cam isn't damaged.  It sounds like the lifters bleed down and then take a bit or warming up to fully pump back up.  Likely due to varnish inside the lifter.  Lifters run ridiculous clearances measured in 0.0001 of an inch, so it doesn't take much.  I would second running a pint to a quart in a fresh fill of oil and see if that dissolves the varnish.  I'm not a fan of the various snake oils out there for stuff like this.  Its worth noting that virtually every oil manufacturer recommends against running additives in their product. 

Personally, in a vehicle that sees relatively low miles like most classics I recommend against synthetic oil, unless the engine is used hard and making in excess of 1.25HP per cid.  The reason is that synthetics are great at lubricating, but not that great at other tasks like keeping seals conditioned.  Over time this tend to result in leaks.  In my 289 I run NAPA (made by Valvoline) 5W30 and a bottle of STP (for the ZDDP for my flat tappet cam), and change the oil once a year.  I only put maybe 2-3k a year on the car at most, and often only 1k, so I'm changing it to remove condensation and combustion byproducts that could cause issues left in the crankcase over the winter. 

I didn't build Gary's motor, but I don't think it's a new build.

Last edited by rpm (5/30/2019 5:25 PM)

GPatrick wrote:

Here's a link to the full Mobil chart -

https://mobiloil.com/~/media/amer/us/pvl/files/pdfs/mobil-1-oil-product-specs-guide.pdf

It does look like the 15W-50 has enough zinc if you are comfortable running that high of viscosity and if the cam isn't damaged.

I'm running "DRIVEN" HR5 10-40 oil in the 390 that's in my truck.  Don't want to start a motor oil debate - just wanting to make sure that your cam hasn't been damaged.

To get rid of the clatter you may just need more viscosity.  A 15-40 or 50 may do the trick.  Some older engines don't necessarily like synthetics so you might try a traditional high-zinc oil and see if your lifters are happier.  Again, this is not an oil debate...

I guess if a higher viscosity makes things quiet you might be OK but I would check the rockers for excessive lash just to be safe before heading out on a long trip.  Just the retentive side in me coming out.



 

Unless I missed something he doesn't reference a miss; just noise on initial start up.  He states that once the noise goes away it "runs better", but that's what would happen when pumped down lifters pump up.  Also, noises have  a tendency to make you think the engine isn't running right.  Were there a miss I'd certainly be more inclined to agree, though such a miss can also be caused by a valve that isn't sealing against its seat.  I'd also go easiest route first.  Two oil changes to try and clear pout any varnish in the lifters is both cheap and easy.  If it doesn't work time to keep digging, but I'd jump off that bridge when I got to it. 

Wow! Sure are a lot of replies.

Here is some history of the engine. Stock rebuild on a C code, bored .030 over. This was in 1993. Ran great but was a tad lacking in the power dept. T5 conversion done at this time also.

2002: After driving it sporadically for a few years I decided to get it road worthy again and see what I could do in the power dept. The engine had around 3K since the 1993 rebuild. Out it came and new domed pistons, cam (flat tappet), Edlebrock 6025 heads and Edlebrock RPM manifold were installed. Rhoads Lifters too (please don't ask me why) along with some cheap 1.6 roller tipped rockers. Again, not to many miles put on it

2012: The valve train was getting really noisy so I pulled the valve covers. The cheap 1.6 rockers were wobbling all over the place. I don't know what went wrong but many had cracks in the fulcrum, some had lost bearings in the tips and the valves stem ends, and guide plates were worn large time. Off with the heads and down to the machine shop. The shop installed all new valves, guides and guide plates.
At this point I replaced the Rhoads lifters with new Ford Motorsport lifters. The cam looked great so it stayed in the block. A set of Stainless 1.6 full roller rockers went on the top along with new pushrods.

Since that time I have put around 10,000 miles per year on the car. More miles than the previous 30 years! It runs great but has always been noisy on startup after sitting a day. I know the roller rockers are noisy compared to stock. I understand aluminum ones are even noisier.
Oil gets changed twice a year. At mid-summer and the last drive in the fall before putting her away for winter. I have never been very picky about oil and usually ran what was on sale. I have occasional run Shell Rotella (diesel oil) as I always have several gallons floating around.

It's noisy on startup and in a few seconds quiets down. Sometimes I think it's only running on 7 cylinders for the first few seconds. I think the cam is fine. I cut the filter open each oil change and have never found any metal.
I'll try some atf and and oil change to a more suitable oil or zddp additive.



 

TKOPerformance wrote:

Wait, am I reading correctly that you installed new lifters on the existing flat tappet cam?

6 years ago!!-------10,000 miles per year!    Sounds like he may have "dodged-a-bullet"!
6s6
 

TKOPerformance wrote:

Reading his symptoms now I'd say not.  That's a cardinal no-no. 

Me thinks you're reading between the lines about my engines symptoms. Basically the lifters bleed down overnight and during the first second or two after start the valve train rattles. It may run rough if it has sat in the 30's for a couple of days on first start. Almost like a valve could be sticking. Nothing leads me to believe there is any problem with the cam or the lifters.
Manifold vacuum is steady at idle and throughout the engine operating range. She's has great low end torque for everyday fun driving, even up here at 8500'. She runs out of breath at 5000-5500 rpm; a result of cam choice. 
An oil change is due in a couple of days as I topped off the crankcase with about 1/2 quart of ATF and she deserves a fresh oil change for the Bash trip.
 

Me thinks we're fixing problems we don't have. Change your oil and be done. In your spare parts box you take to the Bash throw in a spare cam, lifters and gaskets. If you have issues Gary, we'll swap parts at the hotel
Problem solved.

I think we have a higher chance of Colorado to continue to get more snow than mechanical issues. Do I need to carry chains???