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Did I make a big mistake

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JohnB

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Now I'm scared to death.

In reading over a previous thread regarding engine blow-by I found this comment:

"My WAG on this is that the piston rings just did not seat properly when the motor was re-built.Did you lube the rings in any way when doing the assemble???They should be clean and dry when installed!!!If you lube them even a little they can require years to seat,or might never."

When I assembled the engine for my TR2 I did just as the original factory service manual says in Section 21-x, which is to fit the ring to the pistons and then LUBRICATE FREELY, then rotate rings as needed, compress and install in sleeves.

Did I blow it? I DID lube freely as I installed my rings. And now my rings may not seat correctly?

Engine is back in the car and basically ready to fire up for the first time. And now I'm experiencing a major lack of confidence ....... and not sure what to do!!!!!!

John
 
I have personally installed rings in over 100 engines and they all were lubed to some degree when installed. I never installed any dry and never would. I also never had any seating problems, by doing a proper break in drive.
 
"My WAG on this is that the piston rings just did not seat properly when the motor was re-built.Did you lube the rings in any way when doing the assemble???They should be clean and dry when installed!!!If you lube them even a little they can require years to seat,or might never."


Oh, boy.

Over 40 years of engine rebuilding, and that is the absolute first time I ever heard of putting anything in an engine together "dry".

30WT carefully behind the rings, in the grooves, oil the cylinders.......

I am not certain you could even TURN an assembled engine with fresh bore, fresh rings, if the cylinders and rings were dry.
Maybe a 4, but probably not an 8.

I suppose 300K on the engine I did for my own car in 1971 or 1972 doesn't count, eh?

You want to seat rings?
Get it up to 60, shift down to third, go on full compression, kill the ignition, and hold the gas pedal down.
That will wash the rings down but good.

I knew guys with big block Chryslers while I was in the Navy that did that 3 or 4 times in a row to "seat" in their engines.....but I wouldn't.

Just one of those things I'll have to think about.

Think of all the money I could save on oil when lubing up a new engine.
 
Holy ShXt.

I had a chance to think about that for a few minutes.
 
There's nothing like the response from a couple of seasoned veterans to lift that cloud of doubt...........................

Thank you very much!

And if I could ask one more question of you.........what's the BEST way to break in my engine?

John
 
JohnBazzano said:
There's nothing like the response from a couple of seasoned veterans to lift that cloud of doubt...........................

Thank you very much!

And if I could ask one more question of you.........what's the BEST way to break in my engine?

John
Click to expand...

Drive it.

Seriously. Once you've dialed in the timing and are satisfied, hop in. Vary the revs, but by all means, get it on the road. Take it easy the first 500 miles or so, but drive...
 
As Mickey says, stay below 4,000 rpms (my opinion) for the first 500 miles. Drive a lot up and down the gears. For example, running up to 60 mph and letting it coast down to a lower speed, like 20-30 and back up again. Just don't get on a highway and cruise for hours at a constant speed.

Then change oil, retorque head and adjust valves and away you go.
 
I have always lived by when cranking engine up for the first time, keep the rpms up to at least 1500 and not let it idle until engine is warm. So far so good. Then drive it!

Marv
 
Marv, that is the standard cam break in procedure and I mistakenly assumed that it would be done. Good point in pointing that out. I focused more on the later driving aspect.
 
I concur with the advice presented. The rings HAVE to be lubed for proper breakin. If not lubed breakin, may very well turn out to become breakage.

My query is where did you set the ring gaps? They should not be overlapping and they should not be facing the thrust surface of the cylinder wall...

The rings will move around the piston during operation, however unless there is a snag in the ring land, they will turn freely close to the measurements of how they were installed...
 
Lube the rings AND the cylinder walls. I've always done that and if the ring end gaps are correct and offset, the cylinder walls properly honed, they will seat and you will have no problems in this area.
 
I'll add an umpteenth vote for lubing everything. I've not built as many engines as some, but I have done a few. Always used lots of oil on rings & pistons, never had any trouble with them.

I'll add that IMO, "seating the rings" is vastly overrated and mostly used as an excuse when something goes sour. Modern chrome rings are way different than the old cast iron ones, meaning they are already machined to shape and should not have to wear to match the cylinder walls. Oil consumption may drift downwards a little over the first few thousand miles, as the fit improves, but gross oil burning or blowby indicates a real problem, not just rings that aren't "seated".
 
Amazed I missed this. I'm amused there is someone recommending dry assembly of piston rings. Straight engine oil and plenty of it! cylinder walls and piston/ring assembly. Here too have hundreds of engines behind me with only a couple to give any issues... those due to metallurgy, not assembly technique.

As for initial start-up, I do the same basic stuff Marv, Paul and Ron do. Initial start is monitored for the usual drip checks and any oddities, up to normal running temp for a while and varying RPM GENTLY up to 2K or so and back. I'll do this a couple times ("heat cycles") before I load the beasties. Then it's out for a gentle romp up and down the rev range with 3500-ish as the upper self imposed redline for the first 500 miles or so. Drain oil and R&R filter, then press on as if it were a <span style="font-style: italic">real</span> car. :wink:

This has stood us in good stead from A and B series, TRactor engines thru Ferrari, Maser and Mercedes mills. Only "klinker" recently was a Porch-ee 930 with alloy liners... durn'd rings were NOT appropriate for them (I foolishly cobbed it together with client-supplied parts), ended up doin' it twice. ugh. Lesson RE-learn'd. That plug smoked WORSE the more it ran. Pretty disgusting adventure.
 
Put an slant six Dodge engine together using pure STP on the rod and main bearings. The engine lasted 30 seconds. Had to pull the engine replace the inserts with straight engine oil this time and had no problems after that. STP may be a good additive, but I misused it as an assembly lube.
 
A "slurry" of 50/50 STP and oil woulda worked... lots of my racer pals used that, said it would allow the mill to sit for a long time before initial start/break-in. I never tried it, preferring white lith grease as an assembly lube, as long as the thing is gonna be started within less than a month. If it'll be 'stored' before starting I go with an officially labeled "assembly lube"... Whatever I pick off a parts house shelf, no particular brand preference.
 
I'm with ya there DOC. used lubriplate, stp/oil.whatever we had available in the shop. Didn't see any difference in the motors we used to build.
 
Break-in doesn't occur in the first few minutes of running. Break-age does. Rings seat as the engine is running. If they are not getting lubed by then with the oil pump you got serious issues. Warming the engine to operating temp and varing the RPM's will seat rings that have been gapped and installed properly.
 
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