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Posted (edited)

Hi

Here is a short video i made today.

I tested the engine whit a vacuum gauge

By full open trottle the vacuum jumps to 1inches......:-(

Maybe someone can comment the gauge....

In germany testing by vacuum are relatively unknown

Thank u olaf

Edited by Pearsebln
Posted

What a lovely old girl you got there! She looks a lot like my p15 sedan. Your video has inspired me to get out my vacuum guage and try it on my car tonight and see what it does. I bought it a few months ago, but haven't gotten around to trying it yet. I'll post a video link for comparison.

Posted

Very nice S-11! I'd be interested to know where you got it, i.e., old lady car or stored or what 'cause it's basically in pretty sound shape from what I can see.

Posted

Thank u

I bought the s11 on german ebay 1/2 year ago.

The pre owner bought him also in ebay germany 5years befor

And the pre pre owner found him in usa and imported to germany

Posted

Pearsebln,

The vacuum is created in the intake manifold by the pistons sucking air\gas through the carburetor. The gas will vaporize when the vacuum gets high enough and will burn more efficiently; pinging is caused when the vacuum gets too low and the gas condenses into droplets, which is, among other things, an inefficient way of burning it. When the throttle is opened quickly the vacuum will drop until the pistons start moving fast enough to suck enough air to create a higher vacuum and it has long been my opinion that if a vacuum gauge were to be mounted inside the car you could manipulate the throttle by it and get your best mileage. It's a valuable tool when tuning the engine.

Back in the 40s and 50s it was popular to mount an extra sparkplug behind the muffler to ignite the gas that didn't burn during a fast start and that would produce an impressive flame out the rear of the car. Needless to say it was made illegal rather quickly.

-Randy

Posted (edited)

thank u randy,alshere

i know this nexuses.....

sometimes i found not the right english words to tell the right question.

i mean

maybe someone can interpred what the gauge me shows in this video.

the last 3 day i read many about vacuum testing and look some videos on youtube about but i dound found exactly what my gauge shows me.

i read that by fast throttle opening its ok that the vacuum fall nearly to the 3 inches mark.

but lower than 3 inch means bad piston rings....

a extra sparkplug behind the mufler?...intresting,but what is the use of that?

and were is the extra spark pluged? i mean what lets the extra spark fireing

Edited by Pearsebln
Posted
... and it has long been my opinion that if a vacuum gauge were to be mounted inside the car you could manipulate the throttle by it and get your best mileage. ...

If I recall correctly a number of cars from the mid and late '70s had a vacuum gauge on the dash for exactly that reason. They typically had MPG numbers on them instead of inches of Hg but they were basically just vacuum gauges.

Posted

Well now someone has to answer you.

The video shows good vacuum readings. The jumping needle in concert with the metalic rapping is a valve. Since the jumping of the needle is small it may just need to be adjusted.

Posted
Pearsebln,

The vacuum is created in the intake manifold by the pistons sucking air\gas through the carburetor. The gas will vaporize when the vacuum gets high enough and will burn more efficiently; pinging is caused when the vacuum gets too low and the gas condenses into droplets, which is, among other things, an inefficient way of burning it. When the throttle is opened quickly the vacuum will drop until the pistons start moving fast enough to suck enough air to create a higher vacuum -Randy

Are you serious.....everything you stated in that paragraph is just plain WRONG.....did you go to the same auto school as Don Coatney?

Posted

I just watched the vid and I have to agree with FatFreddie....your needle jumping like that at idle means you have a loss of vacuum at a particular cycle of the motor. And with the ticking sound I'd say you either have a loose spark plug, or a valve that needs adjustment, or worse case would be a bent valve.

The reason it's jumping, as stated, is that one cylinder is not getting a good seal during it's cycle and is loosing the vacuum it's generating.

Other then that it looks, and sounds like things are OK with your motor....and BTW it's sure a nice looking car!!

Posted

I'd be doing a compression test! The trans relay clicks well enough though:)

Bob

Posted

Thank u fat freddie

I will adjust the valves aggain,

But fact is....i have massiv blow by

But when the rings and valve guides are ok,like the gauge shows,

Were comes the blow by?

I hope some people shows a video of her vacuum and some other interpred what it shows,

So we all can learn about ,it seems a god tool for engine testing

Posted

fatFreddie,

What I stated was put simplistically but is pure physics and has been proven to be true for generations. I'm not asking you to believe it, though, any more than I would expect you to believe in evolution or the Earth being more than 4000 years old because ignorance has become extremely popular lately and we all know it's more comfortable to be popular than correct.

Next time you study thermodynamics try to stay awake for at least the first law.

-Randy

Posted
Thank u fat freddie

IBut fact is....i have massiv blow by

But when the rings and valve guides are ok,like the gauge shows,

Were comes the blow by?

What would you describe as MASSIVE? Your engine has an open vented crankcase and what the piston is doing in the top of the engine it is also doing in the crankcase ...moving air! Products of combustion are always present in the crankase and that is why you need to change your oil. These products of combustion need to be removed and is what you see comming out of the breather tubes.

The vacuum reading you posted shows a healthy engine in correct tune with a slight valve problem.

Drive it.... your engine is just fine...remember it is not a Mercedes

Posted

here is a link to several different vacuum gauge situations and their causes. Scroll down and click on the green buttons to view different readings and their causes.

http://www.secondchancegarage.com/public/186.cfm

You initial guage reading withthe steady tick of the needle shows a valve remain ope leading to the missfire at idle. Pulling one spark plug wire at a time withthe egine running ( insulated pliers highly recommended) will isolate what cylinder is at fault. (as would a compression gauge check of all cylinders)

The gauge should snap go to zero under wode open throttle, the snap back when the trottle is closed. Highest vacuum reading should be at idle, ther reading should be also reached, or very close to it at crusing rpm readings like 1500, 2000, 2500. Vacuum should be high and steady at those engine speeds.

Posted (edited)
Thank u fat freddie

I will adjust the valves aggain,

But fact is....i have massiv blow by

But when the rings and valve guides are ok,like the gauge shows,

Were comes the blow by?

...Water vapour and unburned fuel vapours cause oil dilution and contamination of the oil in the crankcase.The road draft tube and air inlet at the oil filler cap are designed to get rid of some of the harmful vapours before they condense and mix with the oil.An engine that is in need of a tune up aggravates the problem (oil contamination).It's important that the engine is properly tuned, fully warmed up and driven.

As well as fixing the sticky valve problem,you may also want to check that your ignition system is in good order,(plugs,points,spark plug wires,etc.) and that you have a strong spark...and also that your carburetor is properly adjusted.Lots of tune up info available on this forum... By the way,

you have a very nice car :)

Edited by Ralph D25cpe
Posted

Olaf, I read through your previous posts and see where you had a serious oil drip from your road draft tube..Was the problem found and fixed?

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