[brider]

I did a search, I promise, nothing that exactly answered my question:

F engine, runs great, oil pressure low at idle, but nothing knocks or rattles, and I'm not tearing this one down until something drastic occurs.

But I get a big puff of smoke at start-up, which I understand to mean my valve guide seals are worn. My wife is not happy, and I kind of get embarassed myself when an admiring person in the Home Depot parking lot waits for me to leave, and I see him waving the smoke away from his face as I pull away.

Is there an agreed-upon additive that minimizes this effect? If not, just say so, and I'll stop complaining about it.

[ranger]

Originally Posted by brider

I did a search, I promise, nothing that exactly answered my question:

F engine, runs great, oil pressure low at idle, but nothing knocks or rattles, and I'm not tearing this one down until something drastic occurs.

But I get a big puff of smoke at start-up, which I understand to mean my valve guide seals are worn. My wife is not happy, and I kind of get embarassed myself when an admiring person in the Home Depot parking lot waits for me to leave, and I see him waving the smoke away from his face as I pull away.

Is there an agreed-upon additive that minimizes this effect? If not, just say so, and I'll stop complaining about it.

The additives are a waste of money. Pull the head off and get it redone.

[Fast Eddy]

Originally Posted by brider

I'm not tearing this one down until something drastic occurs.

But I get a big puff of smoke at start-up, which I understand to mean my valve guide seals are worn.

Worn valve guides that cause low oil pressure is "drastic". Fix it.

[brider]

I don't believe it's the worn valve guides (I suspected only seals, but maybe the guides themselves are worn, too) that is causing my low oil pressure, but it's not the pressure I'm worried about (still pumps up good at driving speeds).

But I get the drift-

Thanks guys!

['69 Yota]

Try one quart of power punch. You can get it at NAPA. It made a big difference in how much oil I was going through.

[MarcoPolo]

So is this less chances of a possible piston ring issue?

What would the % of one vs. the other be?

Thanx..... one on me

[NCcruiser1970]

I say piston rings because of the low oil pressure.

[MarcoPolo]

Originally Posted by NCcruiser1970

I say piston rings because of the low oil pressure.

That's why I asked..

[handcannon]

Originally Posted by NCcruiser1970

I say piston rings because of the low oil pressure.

Rings have nothing to do with oil pressure. Main/rod/cam bearings do though. Worn rings can be part of oil burning along with worn valve guides/seals.

[CruisinGA]

I assume his readings are off the stock gauge, if so, any discussion involving oil pressure is not worthwhile until there are some actual numbers from a mechanical gauge.

[splib]

If it's a heep owner waving the smoke from his face, then mash the throttle more!

No, really, X2 on the mechanical gauge.

Where is it registering besides idle? Is it only low on idle? If so, I'd say valve guides, that's what I found on the FJ60 I had with 220K miles on it.

[desertpat]

I think your valve stem seals are worn.
When you shut down the engine, oil in the top end runs down the valve stem past the seal and accumulates in the intake and exhaust, above the valves. The oil will drain into your cylinder if the valve is open. When you fire it up, a bunch of oil has already run down and accumulated - it burns all at once.
These seals are better replaced with the head removed but could be replaced with the head on.

To do this, remove the rocker assy. Work on the valves in 1 cylinder at at time with the piston of that cylinder at TDC (so the valve doesn't fall in the cylinder bore). You can use constant air pressure being fed in through the spark plug port to hold the valve closed (up) while you work on it.

Replace all the seal caps that are located under the valve springs and re-assemble the rocker arm.

I think you may have to buy a complete engine gasket kit to get the new seals for the valve stems.

Don't expect improved oil pressure, but there shouldn't be a puff of blue smoke on start up.

good luck

[brider]

Came in this morning and was suprised to find more entries on this thread!

Compression checks high and consistent, last I checked was 150-ish. This engine pulls steady 21-22 in. vacuum at idle.

I'm reading oil pressure from an aftermarket mechanical guage. Pressure is high at idle when cold, 50 psi+.

At hot road speed (misleading choice of words when talking about an F-engine 55), pressure is a comforting 30-40 psi.

Hot idle is low, maybe 10-15 psi, but the guage isn't that finely calibrated; the needle does drop to it's stop when I shut it off, so I know there IS pressure at idle.

But like I said, the pressure isn't my concern, I'll run this engine until it destroys itself, then look at it as an opportunity to upgrade to a 2F. My concern is the big cloud of smoke at startup. Thevalve seals sound like something I could do when the rig is down for the salt season. but if there was an additive that anyone had luck with, I'd like to try that now, while I'm still driving it.

THAT was my primary question.

Thanks!

[Pighead]

For an oil additive, look for something with the word "Miracle" in the name...
Another way to tell if it is bad rings causing the smoke (and smoke on start-up is usually due to valve seals) is to coast down a long hill, in gear, punch it at the bottom of the hill and look for a cloud of smoke behind you. Big cloud=bad rings.

[MarcoPolo]

Originally Posted by desertpat

I think your valve stem seals are worn.
When you shut down the engine, oil in the top end runs down the valve stem past the seal and accumulates in the intake and exhaust, above the valves. The oil will drain into your cylinder if the valve is open. When you fire it up, a bunch of oil has already run down and accumulated - it burns all at once.
These seals are better replaced with the head removed but could be replaced with the head on.

To do this, remove the rocker assy. Work on the valves in 1 cylinder at at time with the piston of that cylinder at TDC (so the valve doesn't fall in the cylinder bore). You can use constant air pressure being fed in through the spark plug port to hold the valve closed (up) while you work on it.

Replace all the seal caps that are located under the valve springs and re-assemble the rocker arm.

I think you may have to buy a complete engine gasket kit to get the new seals for the valve stems.

Don't expect improved oil pressure, but there shouldn't be a puff of blue smoke on start up.

good luck

If this were the case, wouldn't the engine be running rough as well as having the smoke issue? I experience this and turned out to be so.

[brider]

Marcopolo:

Now that you mention it, it DOES idle a little rough, and I have not been able to identify the cause from my vacuum guage readings. High vacuum, needle doesn't indicate worn rings, bad valve, OR bad valve guides (as the vac-guage literature says it should reveal). Also, it does not indicate ignition, but I plan on wapping over to an e-dizzy this winter. The carb was rebuilt by Jim C., so I don't suspect carburation.

Anyway, your point is a good one, maybe the bad seals are causing oil-richness at idle, making it idle a little rough?

[amaurer]

FYI, here is my writeup/pics for swapping valve seals:
http://forum.ih8mud.com/diesel-tech-...ment-pics.html

Its on a 3B, but I'll bet it exactly the same...