I bought a 1956 Corvette with 24K original verified miles. The engine was rebuilt and bored .030" over in 1965 at about 20K miles. The engine only got 4K miles on it before being parked for 39 years. Chevy 265ci V8 with solid lifters with 6qt oil pan. I also have it converted to a modern screw on oil filter.
I have had the engine running for a few months and have put about 500 miles on the car and will be replacing the rear main seal that leaks next week. Now that I am driving the car I want to run AUTO-RX through it to not only clean the inside, but to loosen up the piston rings, etc.
Given these specific and odd circumstances, what do the experts recommend my exact AUTO-RX usage be? I ordered 2 bottles today.
I am familiar with using dino oil, changing the filter halfway through at 1,500 miles, and not running any on the 2nd oil change for the rinse phase. I'm more curious how much I should add given the 6qt capacity on the initial clean.
Hi! Wow, lucky guy, envy you that set of wheels! :)
I would go for one general application on that engine as it is newly rebuilt and probably quite clean inside. (However, if the rinse oil should come out extremely tary you should run one more.) One bottle might be just too little for 6 qts of oil, so I would recommend 1,5 bottles. Overdosing is hardly an issue with Auto-RX, at least not with htat amount.
Ok, perfect, that's the kind of answer I was looking for. I'm know the engine is very clean on the inside sludge wise with so few on the rebuild, but after 39 years of storage there are spots with tiny surface rust all over the inside of the block and under the valve covers that I hope AUTO-RX will clean.
I'm already on my 3rd oil change since I got the engine running only 500 miles ago. I plan on using nothing but Redline once I'm done with AUTO-RX as Redline has the right amount of zinc and phos for old solid lifter engines. I'm running a dino 15w30 diesel right now for the right amount of zinc and phos. Last thing I want to do is wipe a cam lobe, it has a VERY agressive racing cam.
It's a driving restoration project right now so I only drive it once or twice a week. I'd say about 40-60 miles a week. Sometimes I get as much as 100 miles a week on her.
Yes, original rope seal. I am replacing that with a 2-piece rubber/wire seal.
Okay, you don't have any winter weather worries. You can probably use two bottles for 1000-1500 miles and use a 40 grade for that oil change. You're doing enough mileage per event to get the engine up to full operating temp (20 minutes for the oil to stabilize). That's just to make this fall into a reasonable time frame. If you're not in a hurry, just follow the regular instructions.
Ok cool, so as little as I drive it I'll be good with 2 bottles in the 6qt oil pan? I should also do a full oil change at 1,500 miles or just the filter?
I already bought 15w40 for the task, will that be ok? I don't want to have to hunt down a straight 40 weight that has the right zinc, phos, etc, for a solid lifter flat tappet cam....
The 15w-40 will be fine. The only reason it's a 40 grade is because two bottles might be enough to take the visc down a touch. I wouldn't worry with a rollerized valve train that's already spec'd for 20 grades, but an older pushrod engine (way older) spec'd for 30 weight, it just makes sense to take it up a touch. You don't have the cold to deal with, so the other end of the equation isn't a problem either.
About the interval. If this were a more modern engine with better fuel management, I'd say leave it in and top up as long as you change the filter every 1500 miles. Most mileage beyond the fuel enrichment stage is hollow (for the most part). Not much to speak about in terms of combustion byproducts. With a carb'd engine of this vintage it would be hard to say if the mixture is managed well enough for the oil to tolerate the fuel dilution. I would imagine if you had a good read on the plugs it would work.
So, my official recommendation is to change the oil and filter @ 1500 miles and commence the rinse phase. Keep in mind that the numbers quoted in most cases are targets. This process is used where results are needed in a sensible time frame where they would otherwise not be possible. If you find yourself getting more excuses to drive the thing (as though you need any), a bit more mileage would not be prohibitive. Just remember the vintage of this engine and how long you would sensibly run oil in it without changing it.
