Blow by

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blood hound
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Blow by

Post by blood hound »

I I have a 1960 corvair that was supposedly rebuild pre 1988 when the original owner died it was put in a barn and stayed until about 5 mo. ago when I try to start it has oil coming out the dip stick tube was told rings might be stuck any suggestions on what to do

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Last edited by blood hound on Thu Jul 13, 2017 2:44 pm, edited 3 times in total.
Jerry Whitt
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Re: Blow by

Post by Jerry Whitt »

Many different things could happen to a car that sits for many years. Here are some ideas

1. Drain the oil and replace the oil filter. Measure how much oil was drained. Normal amount would be 5 quarts.
2. Add fresh oil and filter.
3. Do a compression test on all cylinders.

Let us know your compression readings, from there we advise further.
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Re: Blow by

Post by Gearfinger »

I differ in opinion on this. And, this will make some oily mess...

Were this problem mine, the oil cap comes off, the plugs come out, the points lead is disconnected from the ignition coil, a battery charger is hooked up and then we run the starter for 15-20 seconds at a time with a 60 sec rest between. After doing that 5 or so times, spray penetrating oil down each spark plug hole and leave that to work over night. And disconnect the charger.

When you go back to it, put the spark plugs back in, hook up the charger and do the crank and rest again. While cranking the engine over, open and close the throttle at the cross over link and take notice if the cranking speed changes with throttle opening. You are looking for a cranking speed change with the throttle at full open. If you get that, the sticky piston rings are trying to seat to the cylinder walls again.

If you are not sure this is working, try cranking the engine over with and without spark plugs. If it cranks slower or with a rhythm with plugs in, you are getting some where. After that is the time to drop the oil and filter.

Disclaimer: My advise is worth every cent that you are paying for it...
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toytron
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Re: Blow by

Post by toytron »

I would agree with Jerry! Except it is 4 quarts plus what the filter holds which is approximately 1 quart. I know it might be nit picking but I don't want you to freak out when you drain from the pan and only see around 4qts. Definitely do the compression check! REASON....you already tried starting it NOW it is time to diagnose. Do Not try to fix anything until you have diagnosed first (actually second). If you do you run the risk of damaging things further unless you don't mind doing a rebuild then have at it.
Compression check, take out all spark plugs, disconnect distributor, hold open chokes and throttle plates. Write down findings for each cylinder. Leave the car in that state until you post your findings before you attempt a wet cylinder test.

Ed Stevenson

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Re: Blow by

Post by Gearfinger »

I'm not here to step on toes or cause friction. My bonafides include 45 years of air cooled experience at dealers and as an independent which cause a level of confidence of opinion that can be offputting and seem coarse. That said, to believe that a change of oil will lead to a solution of the stated problem is magical thinking.
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Re: Blow by

Post by 64powerglide »

How much oil is in it? Check the level on the dipstick, if it on the full mark then do as Gearfinger said, lube up the cylinders. My 64 sat for 20 years & It runs great. You have nothing to lose but a little time.
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lostboy
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Blow by

Post by lostboy »

The lesson learned here... absolutely remove plugs and spray some sort of lubricant (opinions vary) into each hole BEFORE rotating the engine. That's what I did with mine that had been sitting since 91 with mice living in the carburetors. So far, still running and well.


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Re: Blow by

Post by skipvair »

Marvel mystery oil is good at loosening stick rings


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Re: Blow by

Post by WinginEngineer »

I had suspected stuck rings on mine. I sprayed PB blaster in the plug hole and let it sit. Still had no compression.

Now, it turns out my rings had .090" end gap and my pistons were short pistons off the longer stroke late model motors but with a short stroke early model crank, so I was never gonna get compression anyway, BUT when I pulled the jugs I had nice wet oily rings on the bottom of the pistons and bone dry rusty rings on the top half.

Moral of the story? Bend your spray tube 90 degrees to make sure you actually get all the way around the piston....
Kevin - Phoenix/Mesa, AZ
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Re: Blow by

Post by lostboy »

skipvair wrote:Marvel mystery oil is good at loosening stick rings


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I've heard that. The guys on the sohc4 (a vintage Honda motorcycle forum) deal with this all the time, engines that have been sitting out in the pines and whatnot. They have a whole formula for stuck or sitting engines that starts with Marvel.


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Re: Blow by

Post by toytron »

The oil change was not a magic bullet but because it had been sitting a long time. I think that is reckless and irresponsible to tell a guy to just keep cranking his engine with old oil. With the cost of replacing the oil and filter as opposed to rebuilding an engine because you cranked it with old oil in it. Coming across offputting would be the last of my concerns.

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Re: Blow by

Post by Gearfinger »

Penetrating oil works very well with old engine oil and would contaminate whatever is in the oil pan.

Please explain what damage could possibly happen to this unit by following my suggestions. Something more substantive than subjective opinion...
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toytron
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Re: Blow by

Post by toytron »

Really! Deteriorated oil filter media, lack of proper oil pressure, lack of oil to bearings. But do whatever you want to your own motors but I think it is irresponsible for you to suggest that others do the same haphazard "fixes" just because it had "worked" for you.
BTW it is funny that you bring this up at this time while on the other forum there is a topic now about the quality of responses that people give on these forums.

I understand that some or possibly many people want to do the work on the cheap but that does not mean that they want to possibly wreck their engines in the process. What you suggest was something that I use to see all the time when I was a kid and worked at a friend's junk yard back in the 70s just so they could sell a "running" engine. Not the practice that I hope goes on today but you never know.

Ed Stevenson


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