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a lot of blow-by; what's going on? 170 cc. for a 60' V200
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Author:  Eatkinson [ Sun Nov 20, 2005 3:05 pm ]
Post subject:  a lot of blow-by; what's going on? 170 cc. for a 60' V200
Hello all. My station wagon is a 60V200. It was used from 1960-1970, then was parked and sat neglected, not running until I rescued it a year and a half ago. It has 68K original miles on it. Professional care was taken to revive the original 170cc six. Cylinder chambers were well-lubricated before the engine was turned over. After priming the carburetor, the car started right away and runs very well considering it's 35 year nap. I've been driving it a few times a week now for about the past year and a half.

The '60 170cc. has an open exhaust ventilation system. Ever since getting it running again and driving it, I've noticed that there is a fair amount of blow-by coming from under the oil cap. There is also some being emitted from the PCV stem. The surrounding area around the oil cap on the valve cover is moist with oil.

What is going on exactly beyond the obvious "it's a 44 year old car that sat for 35 years" explanation? Could this be taken care of with something other than an engine overhaul? I think that if I were to close the exhaust ventilation loop with a newer carb with a PCV outlet, the car would suffocate itself with the amount that is being emitted.

Compared to my 64 dart with a 225 that has seen regular use all it's life, the Dart emits NO blow by at all from the oil cap and the valve cover around it is completely dry.

Thanks in advance, for your thoughts.

Evan
Author:  mopar_nocar [ Sun Nov 20, 2005 7:34 pm ]
Post subject: 
have you had the valve cover off? could be the return path for the oil back down to the pan is partially stopped up causing excessive oil to stay on top. that could cause what you are seeing.

sb
Author:  Eric W [ Sun Nov 20, 2005 7:52 pm ]
Post subject: 
Classic symptoms of shot rings. It may not burn oil, but blow by will occure with rings that are worn enough for combustion gasses to escape past the rings and into the crank case. Been down that road with the engine in my Satellite. A closed system, it was bad enough that I had to change the air filter once a week because it was cloged with oil. A free engine from a '73 Dart fixed the problem. :lol: A ring job will fix yours. I doubt if a simple break the glaze and install new rings will work though. After setting for many years corrosion may have had a negative effect on the cylinder walls. Another possible reason for the blow by.
Author:  SlantSixDan [ Sun Nov 20, 2005 9:49 pm ]
Post subject: 
Quote:
Classic symptoms of shot rings.
Well, shot or stuck rings. Me, I wouldn't give up on the engine just yet. I'd buy a gallon or two of Kroil (and only Kroil), introduce a goodly amount into each cylinder through the spark plug holes, loosely replace the spark plugs, and let the engine sit a few days without running. Meanwhile, I'd pull the valve cover and check the whole top end. 1960 engines tended to bend the rear four pushrods and partially stick the lifters, even under optimal conditions (which don't include sitting for three decades and half); a bent pushrod or reluctant lifter can create tremendous blowby even if the rings are halfway decent. Excellent bet the valve stem seals and spark plug tube seals are all crispy critters, too! I'd pour the rest of my first gallon of Kroil into the crankcase.

After a few days, I'd yank the spark plugs again, line the RH inner fenderwell with shop rags, and crank the engine over on the starter to eject whatever liquid Kroil remains in the cylinders. Back go the spark plugs (new NGK ZFR5Ns with their ring gaskets!) and fire up the engine. It'll smoke as it spits out the Kroil. Run it awhile, drive it awhile, drain the oil. If the oil's black, as it probably will be, I'd go ahead and do an expensive, slow flush (as distinct from a cheap fast flush).

If none of this managed to reduce the blowby, then I'd look at overhauling or replacing the engine.

Eatkinson, check with 60Seneca who just went through old-1960-engine issues on his car. We found bent pushrods due to stuck valves, toasted valve stem and spark plug tube seals, all kinds of fun stuff. Now it's running great.
Author:  Eatkinson [ Mon Nov 21, 2005 1:43 am ]
Post subject:  Thanks
Dan-

Just spent a bit of time reading up on 60Seneca's engine saga, though I missed the post where all was finally resolved.

A couple questions:

1. Will bent pushrods be an obvious thing, once I remove the valve cover? I don't usually do the work on my cars myself (though I'd like to change that). I'm generally familiar with the pushrods, lifters, valves, etc., but how will I know exactly what I'm looking at/for? I've never done it before.

2. After I remove the plugs and let the Kroil set in the cylinders for a couple days, I turn the engine over to eject the Kroil out of the combustion chambers. At what point am I refilling the oil to then drive it around?

3. The expensive slow flush: I read about it. Sounds like a good procedure for my engine. When you say expensive, are you talking about the cost of all the materials used in the exercise? As in, two gallons of Kroil, multiple new oil filters, etc?
Author:  SlantSixDan [ Mon Nov 21, 2005 8:53 am ]
Post subject:  Re: Thanks
Quote:
Dan-

Just spent a bit of time reading up on 60Seneca's engine saga, though I missed the post where all was finally resolved.
A lot of it was via PMs back and forth. You may want to message him for further details.
Quote:
1. Will bent pushrods be an obvious thing, once I remove the valve cover? I don't usually do the work on my cars myself (though I'd like to change that). I'm generally familiar with the pushrods, lifters, valves, etc., but how will I know exactly what I'm looking at/for? I've never done it before.
Well, with the engine running, each pushrod will be spinning. You will be able to see grossly bent pushrods by looking for side-to-side wobble as they spin. And if your rocker assembly is as crudded-up as it's very likely to be after lengthy sitting, when you remove it for cleaning you can simply pluck each pushrod from the engine and roll it along a piece of plate glass to check easily for even very slight bending.
Quote:
2. After I remove the plugs and let the Kroil set in the cylinders for a couple days, I turn the engine over to eject the Kroil out of the combustion chambers. At what point am I refilling the oil to then drive it around?
Well, you won't have drained the crankcase oil, so no refilling will be necessary. Did I misunderstand your question?

Quote:
3. The expensive slow flush: I read about it. Sounds like a good procedure for my engine. When you say expensive, are you talking about the cost of all the materials used in the exercise?
Yep, that's it.
Author:  Eatkinson [ Mon Nov 21, 2005 2:26 pm ]
Post subject:  Ok
You didn't misunderstand my question Dan. I mis-read your post and assumed I had drained the oil out of the crankcase before pouring in the Kroil.

When removing the valve cover, are there any special tools I'll need beyond a socket set, various pliers, etc.? Given how much I've repaired my car myself, I don't have anything other than the standard tools. Will that be enough?

Thanks.

Evan
Author:  SlantSixDan [ Mon Nov 21, 2005 2:48 pm ]
Post subject: 
Very easy to remove the valve cover (7/16" bolts hold it on, though you'll also have to remove the bolt that secures the road draft tube to the engine block)

Very easy to remove the rocker assembly if you need to do so (Again, just held on with bolts)

Remember, you'll need *at least* a new valve cover gasket when you go to put it back together -- try for a rubber one rather than cork -- and you'll want some new spark plug tube seals, too.
Author:  Eatkinson [ Mon Nov 21, 2005 5:52 pm ]
Post subject:  perfect
Thanks Dan. Gonna get into it as soon as I can. Probably have to order some of the chemicals first. Don't have any of them. Four further questions regarding that flush:

1. When pouring it into the crankcase, it's all through the oil cap, correct? And you speak of draining the mixture out of the engine a few times; are you talking about draining it through the oil drain? Not to be thick, but for the uninitiated....

2. You wrote about running the engine at a steady 1200-1700 RPMs with no acceleration or load. Is 1200-1700 RPMs idle speed? I'd assume so, since you said no acceleration...?

3. My engine is the 1960 170cc six. How many quarts is my crankcase?

4. When replacing valve stem seals (I assume I could tell if the seals are toast; they'd be brittle and cracked right? If not...how do I tell?) do they just push on over the valves, or how do I replace them?

Thanks so much for all the help. It's very appreciated.

Evan
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