Well I finally changed the oil today using the recipe that I originally posted. I spoke with the a gent at the Shell Bulk plant who started there when he was 12, his father owned the place.
I came prepared with the tech sheet, and MSDS from Rislone ZDDP additive. Along with the Shell spec sheets
, and MSDS from both the Rotella T1 30 single
weight, and the the 15W-40 Shell Rotella T. Turns out he's an oil guy, and before I completed, he interrupted and said, first you have no problems mixing the 2 shell oils as the are from the same base stock, with almost identical additive packages. Both are API certified CF or better, both are low sulfated ash.
He said what you need to be concerned with is the oil shearing of the multi-grade oils. I also brought with me my original Perkins manuals
which listed the oil spec, the original manufacture's spec. He pulled out a 3 ring binder from years gone by and we compared the original spec oil API rating, for shear, Sulfated Ash, Zinc, and Phosphorus.
We concluded with that with my recipe, that I would have a better oil then original spec meeting all of the requirements, and then some because. He felt that the amount of Rislone being added would raise the ZDDP to levels of the original spec of the Perkins required API. Rotella T is made from a type II base oil, and the original spec is from a type I base oil, which increases its shear value, and luberosity.
So now comes time for the oil change
. First the port engine, but it's also time to adjust the valves, as I'm at 400 hrs since the last time. My Perkins manual says to adjust em hot at .010, and the subsequent service
bulletin says adjust em cold .012. So I have concluded that I will adjust em cold and check em hot with a .010 go/no-go .011 feeler gauge.
The last time the valves were adjusted, I hired a well known local Perkins mechanic
, as I just didn't have time to do em. So cold after 400 hrs I found a couple of intakes that were a little tight go/no-go .011/.012, and a couple exhaust
that were loose go/no-go .013-.014. I checked and adjusted so all were in spec. Start the engine run it in gear
at the dock
, until they are up to temp. Then check the valves hot all are go.010, no-go .011. So I change the oil and filter.
Next the Starboard engine, pop the valve cover, and run #1 cylinder up to compression
stoke and with a wholly sh..t .012 is really sloppy. I don't hit a no-go until 16 for both exhaust
, and intake. I make the the adjustment as required, then move to the next cylinder, it again is a no-go at .016, so I work my way though the remaining 4 cylinders and they are all no-go at .016.
Now I Know my Perkins has flat tappets, but being a reasonable man I know that 12 tappets are not going to wear that exact same. Both engines were rebuilt at the same time, and both have run the same amount of hours, with the same oil change
regimes. The only conclusion is the hired mechanic
picked the wrong feeler gauge when he got to this engine. I have been ruining now for about 3 years since the last valve adjustment, and I manage about 125 hrs a year.
So I start it up, and at Idle I'm completely surprised she is running as smooth as I can't believe. It's a Night and Day difference, I'm shocked that I didn't notice in the past 3 years what a difference proper valve adjustment made. Well I did sort of notice that the Pyros showed an elevated EGT on that engine, but at idle was with in 25F, it wasn't until I got above 2200rpm or I was running against a tide that this engine would show about a rise of 100F difference on the Pyro, but at normal cruise
it was with-in 25F
So now I run her at the dock
, bring her up to temp, shut her down and check the valves all are go .010, no-go .011.
So I change the oil with my new recipe. Start her up, after oil is up I bring her up to 1,000 rpm
. I go back to the engine room, just as I get there BANG, POP and all kind of racket, to the what to me sounds like the engine coming completely apart. I ran back to the Helm
, hit the kill switch.
Now back to the engine room which is in the cockpit
with a deck hatch
, my heart in my mouth, just then I hear a Harley with straight pipes revving through the parking lot, and a chopper landing at Ch13TV, which is just a block away.
That's when I realized I didn't blow my engine, yep sure as ****, no problems in the ER, so I restart her and shes purring like a kitten.
In the end it was a beautiful spring day in Seattle
to do annual maintenance