My 75 D100 still has to pass air quality control checks. I replaced my carb (Thanks again Dan), had a complete tune up with plugs, dist, cap and wires. There is a new fuel pump, filter and premium gas. It still has a miss and my mechanic says that it is probably a stuck ring.

Where to begin? In both categories I way exceeded the output levels.

Thank you

Adjust the valves yet?

I'm curious about what one can do to unstick the stuck rings without disassembling that engine? (to ask one's and my question at same time.)

Cheers, Wizard

Did you try a compression test? Not sure if stuck rings will show up that way.

How about penetrating oil down the spark plug hole?

If you have a miss you'll fail HC miserably. Do a compression test. If you have a real low cylinder it could be valves or rings. A wet compression test will help bad rings a lot more than a bad valve. Also, don't overlook misadjusted valves.

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Joshua

Marvel mystery oil!!! Somebody here on the forum reminded me of it to use on a gummed up slant i've been tinkering with. It does work. I'm curious, just how bad a miss are we talkin about? You've pulled the plug wire when its running and it makes no diff? Also don't overlook the pushrods if nothing else works, possible one is bent a bit.Good luck

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83 B-150 slant 6,4 speed. 79 B-300 360 pathfinder 4x4. 74 W-300 318 4x4 git-r-done 80 B-100 sl6,4speed

How often do you drive this vehicle? If you drive it everyday, it will be harder to unstick, than if you drive it seldom. Some stuck rings get tht way simply from inactivity.

Sam

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Kreen is a really excellent top-end cleaner. The bottom end can often be safely cleaned with my soup recipe.

Premium gas isn't helping, and could well be hurting. Use regular.

A miss can be caused by an ignition fault, a lack of compression, a fault in any of several parts of the emission control system, or a vacuum leak. Have you tried spraying carburetor cleaner at each of the six intake-to-head junctions to see if the idle smooths out?
Usually works the other way round for me.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I will do a visual inspection for vacuum leaks and look at the emission equip. and then remove the plugs to see if there is a change first. Next, I will do Dan's soup recipe and try the Kreen. Can I purchase this (Kreen)at a supply store or do I need to mail order?

I will then do a compression test, valve adjustment and if that does not help.... I will beg for more assistance.

I have quite a few different vehicle that I work on (88 300zx, 95 BMW 525i and 99 BMW 528IT) and the people here have given me more information than any other site over the past five years. Thank you all and I will keep you updated!

Matt

The downside of Kano's products (Kreen, Kroil, etc.) is that they are hard to find locally. You pretty much have to order directly from Kano. Get some Kroil while you're at it!

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

The way I parsed Sam's sentence is different than you did. I think what he was saying is, "If you develop a stuck ring in a daily driver, aint nothin' short of a tear-down that's going to un-stick it. But if you find a stuck ring in a seldom-driven car, it'll probably un-stick pretty easily." And that agrees with my experience- "stuck" rings in engines that are regularly operated are usually actually broken rings, or rings so packed with hard, hard carbon from persistent oil consumption that you can't ever really dissolve it with the usual treatments.

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Oh! Yeah, that makes better sense than the way I was parsing it.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Parse me a beer......

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Yeah....Im the one who destroyed this rare, vintage automobile.....

I've gotta go out and dig up some parse snips, so I'll quit being a pain in the parse here. I'd say more, but I'm trying to keep this post parsimonious.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I almost parsed out laughing at that one. Yes I did mean if you drive the engine every day, and a ring is stuck, it might be stuck for good. However, back in 1962, I had a 59 Pontiac with rings that stuck even though it was a daily driver. I put automatic transmission fluid in the crankcase, put a cardboard over the radiator, and let it idle for 15 minutes. I figured I was either going to fix it or break it. I drained the stuff, changed the filter, filled it with good oil, and drove that car another 50K miles with no oil burning.

For this reason Dan, I found your "soup" very interesting. I noticed it is 2/5ths ATF, if I counted the order of your ingrediants, and related it to the proportions you indicate correctly .

So, you might give Dan's soup a try. I didn't know about Marvel Mystery Oil at the time, but from the design of the can, it has to have been around since long before that.

At the other end of the specturm, I put a junk yard engine in the Dart below that I drove for about 30k miles before the new one went in. When I first started it, it lay down a horrific smoke screen. I drove off up the road, and after about 5 miles, the smoke went away, and it never burned oil to speak of after that. And that was just regular, real dino.

One more thing: When I tore down the older, original engine, many of the rings were broken. And it ran like that. I always wondered if the rings broke because that original engine ran on the ragged edge of preignition under light, upgrade throttle. Anybody know if preignition can cause failed rings? And, have you been driving with a more or less constant pre-ignition situation? Did it come on under light throttle up grade as mine did? That seems to be a common state of tune of the slants I have known.

Sam

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could be as simple as buy a hotter ignition coil or performance one made my miss go away but that was the factory miss yours might be a different problem.

Kevin

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