Fifty-Years of Engine Deposits

[Grayscale]

My 1975 2F has a history of being an oil-burner. With the manifolds off, there was quite a bit of carbon deposits on the intake valves. I fixed the leak thru the valves a few years ago. The spark plugs kept fouling, but, I could deal with them as a symptom.

Late last year, I installed Valvoline's 5W-30 Restore and Protect. I'm going to spoil the story here and just say that the camshaft didn't grenade, yet. It is a new oil that has been proven to reduce both sludge and varnish deposits, including deposit removal from piston ring lands, and piston skirts, which is unique in an oil. It isn't an oil flush, as it is specified for new engine use as well. I'm also using, in the fuel tank, a bit of Lucas Fuel Injector Cleaner for upper cylinder lubrication, and Techron High Mileage for fuel stabilization.

After about 100-miles the oil is opaque black, and it is getting changed.

Now, the spark plugs get dirty, but the electrodes are all self-cleaning. Number 5 and 4 are still having issues, but, this was early on.

There has been a huge improvement in the cold-driving ability of the 2F. I never let it warm-up, I just fire it up and drive. The throttle is not as sensitive to input when driving the engine cold. I can basically keep up with traffic, other than they are peak accelerating, when I'm performing clutch and gear shifting. I need to perform a vacuum check, and do a dry compression test.

It seems to have helped my Datsun with a slight tick that might be related to stuck piston rings and/or frozen rings in their lands. I'm also using it on my dad's LeSabre that once drank fuel-injected gas to the point where it nearly consumed x2 the gas per mile - efficiency has improved, but, I'm thinking that that one had clogged injectors, prior to regular service, fresh gas, and Techron.

I really think that if you have an old engine, it is worth trying. Maybe just two or three 100-mile change intervals of it, just to see? Getting the rings to seal is going to be more important after years of running bad. You can't make power if you loose compression to blow-by, and you can't make vacuum at all temperatures (part expansion / contraction) if the rings are stuck in one position. And, I don't really know that this 2F wasn't ever rebuilt, but, it is also not impossible that the junk drained from the pan is sludge and varnish that is half-a-century old, and the motor runs much better without it.

 

[charliemeyer007]

Rings clogged - Pull the plugs, squirt in a bunch of Marvil's. Grab the fan and pull the motor threw a full revolution to make sure the marvil's is distributed. Let soak for a day or so - redistribute and soak for another day or two. Throw a blanket over the motor - use the starter to whirl it over a good amount. Put in plugs and go for a good long drive. Several treatments might be required.

#5 is the jug that will burn due to a leaking vacuum booster.

 

[pb4ugo]

This thread might be of interest to you. He 1st posts his issues. On page 2 He tries something simple with interesting results.

I need very basic motor rebuild advice

Hi. I've been chasing a small hesitation issue for a while ... and prior to that I was chasing a pinging issue under load, which was solved by more compatible timing and higher octane fuel. Forum folks theorized that the pinging was probably caused by carbon buildup on the pistons. That was...

forum.ih8mud.com

 

[Grayscale]

Yeah, like SeaFoam, but, the Valvoline has more appeal. Like fixing it in real-time.

I just did some Cruiser stuff. I checked the oil, and it is still really clear. After the initial seven-or-so-quarts, everything was suit-like. The two plugs were still suffering from build-up, but, the engine runs really tight.

It makes me wonder about my '73 with a couple of F motors? It suffered from all kinds of dieseling, and the only way to stop it was to stop it in gear with the brake on. Even about seven years ago, my Datsun had dieseling. I wonder if all that is possibly behind us with new chemicals - synthetic petroleum products? They say that they engineered a chemical to target varnish, and a chemical to target sludge, and had a lab in Mumbai manufacture these theoretical detergents. Then they dialed-in the concentration so it doesn't clean the engine so quickly that it damages it. The new engines are high-compression, so using the gas and oil made to prevent pre-ignition isn't a bad thing in these older low-compression engines.

 

[pb4ugo]

Idk, you're thinking you have stuck rings and carbon like the OP did in that thread, a can of seafoam carefully down a running carb might give you similar results.

 

[Grayscale]

One of the neat things about having it as part of the oil, and not a stand-alone application is the blow-by itself becomes the solution. So, at the piston rings oil, mixed with fuel, mixed with moist exhaust is being fed into the crankcase in a kind of aerosol / gas mix called blow-by. But, one of the engineers who developed this product explains that with that blow-by, some of the sludge, and varnish-cutting detergent goes with it. So, the PCV system should be able to address intake issues as well? Hopefully. To start with, a reduction in the volume of blow-by, as they call it an "active shield." That is good, as the engine shouldn't have to burn as much oily, varnishy, exhaust, coming thru the intake via PCV. But, also, when the motor shuts down, the crankcase gasses get to be shared with the carburetor bowl, as there is no engine vacuum pulling fresh air in. So, instead of exposing my investment in an out-of-stock, City Racer 2F Aisan carb to potentially varnish forming environment, it might actually be a bit more self-cleaning. The other PCV-area that varnish forms are those 'gas filters' for the intake emissions vacuum barbs. One of them was totally clogged with carbon.

The economy of it is actually appealing as well. It is going to be less expensive than doing SeaFoam, or Marvel Mystery Oil, and it isn't diluting the oil.

I'm pretty sure that the motor needs even more sealing-up. So, I'm not considering the Valvoline Restore and Protect a total victory, yet. For that, I'd stuff dental floss between the pistons and cylinders, and do a two-stage cylinder hone. That and a valve lapping. Measure the cam shaft wear, and maybe make lash adjustments to balance it. The rust inside this thing was bad, enough to destroy carburetor butterfly shafts, so I woudln't be surprised if it always burns a tiny bit of oil, having pitted cylinder walls.

They say that warming-up an engine can increase fuel-dilution of the oil by like 40-percent. So, the routine is to just start driving, preferably with soft throttle, under load, up a slight hill, or whatever. The load increases pressure in the cylinder, pressure increase is a temperature increase given a constant volume, and adding more air and fuel will add mass (PV=nrT - the Ideal Gas Law). So, you save time and oil, having working rings. The Valvoline product makes a perfect cold-weather oil (5W), and it really seems to help the old engine before there is movement on the water temp gauge.

 

[charliemeyer007]

I favor consistency - drive them the same way all the time - reasonable as in not lugged to death or rod throwing valve floating rpm's. Regular Oil/filters changed often is way better the premium stuff infrequently.