Curious case of lost and found cylinders

[ArdWrknTrk]

Because, like I said, it has a high detergent package and is intended for extended oil change intervals.
It also has more ZDDP than SI oils, though not nearly as much as it did before diesels had cats..

Did I not spell all this out?  

[viven44]

I intended to type the question as "Why diesel, because of the ZDDP?" then took that out because the ZDDP part.. I don't have personal knowledge. I have only heard second hand.... I see on point 3) that you mentioned the detergent part, I really did miss that.. but also implied the same in point 1)... sorry .

What viscosity diesel though ?

[ArdWrknTrk]

What environment do you live in?
Is your engine worn?

I would go with the lightest W rating I can.

The second number is at oil operating temperature, generally 225-250F???

So, you always want the oil to flow to the bearings as fast as it can on startup, but you (like me) might have poor pressure at operating temperature.
I jumped on an Amazon deal for a 5l jug of Motul10W60, and it worked out great!
I'm not liking the idea of a $50 jug of oil (was $32) but filters are still cheap, and it's NOTHING compared to a dealership oil change on a Mercedes or something where the damn filter alone is $65.

I obviously haven't been driving much, given how I was nursing the rear, and now only have front wheel drive.
Plus, my leg means it's impossible right now to drive clutch.

I'll drive it 6-7kmi, which is where I feel modern oils in a vintage engine should be changed.
Whatever... oil & a filter is ALWAYS cheaper than a new engine.  💡

[viven44]

Thanks! I have ~25PSI when fully warm.

[viven44]

Just a follow-up

I have driven about 250 miles since the oil change. I used 1/2 qt of Rislone, thanks for all the other suggestions. Its just that as soon as I heard Rislone I ordered it for a Walmart pickup.

New plugs are looking great after the 250 miles



The compression values are as follows
      FRONT
110           110
100/110     110
100/110     110
120            120

If you recall when I had the issue the numbers looked bad
   FRONT
120    110
60      102
70      100
120     80
   
No change in compression numbers with/without WOT except cylinders 6 and 7 where it improved by 10PSI and thats why you see 100/110. Wonder if that suggests that the intake valves are gummed up. Maybe a seafoam carb treatment before next oil change ?

[Gary Lewis]

That’s good improvement.

As for the Sea Foam, don’t do the one where you pour it into a running engine in your driveway. Your neighbors will NOT like it.   If you are going to do that go out into the country to do it.

But I think getting a few hundred miles with the Rislone in may do the trick w/o Sea Foam.

[viven44]

Yes its that nasty kind. I have used it before in my alleyway! I am not worried about the neighbors anymore as all the issues are out in the open and the city came and gave me 'clearance' to work on my cars. Other than neighbors are there any other downsides ?

Rislone wouldn't go after any build up on the back of the intake valves, right ? That's why i'm considering this.

Just curious on the compression numbers though. On a Bullnose of any kind (302, 351, 460) I have never measured a compression value over 125PSI which is pretty much what is expected (8.5 * 14.5 PSI/atm) but was curious if my understanding is correct.

[Gary Lewis]

Right, Rislone won't get the back of the valves.  So if you have been cleared go for it.  You won't have a mosquito problem.  

As for compression #'s, I've seen 140, but I don't remember what.  So you may be right.

[ArdWrknTrk]

I used to mist water into a running engine to steam clean carbon deposits.💡

You can also spray MMO in through the carb.
Those valves are opening and closing quite quickly (at 600 rpm, 300x a minute, or 5 times a second)
It will loosen varnish and other deposits, while smelling minty fresh!  😆

[viven44]

Thanks Gentlemen! I will need to do one of these things definitely. Maybe another 500 miles down. I'll test for compression before/after so the effects are documented.