Vacuum Tuning & Recently Advanced Vacuum Advance Fallacies

1941 - 1945, MB, GPW Technical questions and discussions, regarding anything related to the WWII jeep.
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TonyStandefer
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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by TonyStandefer » Tue Jan 03, 2017 7:21 pm

I don't understand why there is any criticism of all this effort to help keep owners use a recognized diagnostic/tune up tool.

Instead of criticizing why don't you put forth the same effort at instruction/information. Using modern/available tools. Most of us don't have Joel's array of military diagnostic tools and must make do with Napa grade tools.

Full disclosure, I use a vacuum gave to tune my jeep. My high school auto mechanics teacher was an advocate of the vacuum gage. He even had one installed in the dash of his street rod.
Willys MB 340931. DOD 6-9-1944
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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by dinof » Tue Jan 03, 2017 7:46 pm

Let me say for starters, I have always used a timing light. Why is it so hard to use it? You just point the thing down there and get the mark on the flywheel.
Said that, listening to John time after time about a vacuum gauge got me intrigued. I bought one and tested my jeep and it scored steady needle in the green. Now I know my jeep is tuned perfectly, and it makes me feel great that I'm doing good mechanic skills, backed up by the VG.

But, the vacuum gauge can tell you about so much more. Valve timing, engine timing, back pressure, valve sealing, compression, and then lets not leave out that it also tests fuel pump pressure. And what about synchronizing multiple carbs? I remmeber something about that if I'm not correct. I'm a better mechanic with this by far. So thanks John, for getting guys like me to discover that there is always a new thing to learn about simple diagnosing of our jeeps. More than you think John, others are learning from what you say.
Dino Falabrino
On the "G" since 1998.
1943 GPW 102310 DOD 3-3-43
1928 Model A Roadster Pickup
1930 Model A Tudor
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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by artificer » Tue Jan 03, 2017 8:54 pm

In the 60's & 70's most every Motor Mechanic [in Western Australia, where I taught] was practically trained in & used vacuum gauges.

Unfortunately there is some misapprehension that any engine issue can be established precisely with a vacuum gauge by those who have never been taught what to expect, but just read through Snap On's interpretation guide or read & perhaps misinterpret various web offerings. That is why I am putting in this extra educational effort.

Diagnostics:
Without doing anything except plugging in a vacuum gauge & hooking up a dwell tacho, one can get a very good idea of what is happening with all engine running systems. This systems stuff was described in my third post

Mechanics want to know this as their customers wish to pay as little as possible to get a perfect result.
That means not putting in useless labour or replacing anything that is good.
Parts changers & those who rely on guessing, are lost in the fog!

So, if the vacuum gauge indicates nothing is wrong, why would anyone be pulling the side cover & adjusting valves for example doing a compression test or replacing anything?

All this done in a few minutes. One can switch between dwell meter & tacho & make minor adjustments.
Once done vac gauge re-time the engine & road test.

Customer is happy with a 30 minute minimum charge & their engine is running perfectly. Nice stuff.

This is an actual reading on my Jeep & not a doctored shot. It indicates absolutely nothing is wrong.
Anyone [experienced or not] with an L/F134 [or other engine] can get an identical reading & it would be silly doing anything, like even checking ignition, spark plugs, points, tappet adjustment, do a compression test or anything else.

Just remove the dwell tacho hookup & vacuum gauge, replace the plug in the intake manifold & away you go. Road test & check for any possible spark over advance as has been described any number of times.

Image

Any issues indicated by the vacuum gauge?

BEWARE....depending on the engine condition there may be multiple issues overlapping so then we rely on other skills like shorting individual spark plugs for example.

The mechanic would then hone in & prove exactly what issues need attention.
Perhaps using a compression or leakdown test & such for example, or going straight to a blown head gasket, tappet adjustment or the valve spring area.

The customer knows they are not paying for someone guessing or paying to have labour that is unnecessary or replacing parts that didn't need replacing.

Once the work is done the mechanic would again be hooking up the vacuum gauge, dwell & tach & set up to get that perfect reading. Road test & final timing adjustment.

Remember all possible vacuum leaks must be capped off when trying to interpret a vacuum gauge when testing & adjusting engine/s....not forgetting that a vacuum gauge will identify a vacuum leak & you need to know it is associated with the engine & not brake booster, vacuum advance or anything else.

You G503 owner drivers can use a vacuum gauge to achieve pretty good diagnosis & adjustments yourself, so forget the deniers, listen to the converts & spend $15 to give it a go!

My Mercedes 500SL has a vacuum gauge on the dash, as do many other models.
With a little knowledge one can diagnose possible engine or even brake booster issues, if there are any, by observing this gauge when the brake pedal is being applied, held & released.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Tue Jan 03, 2017 10:00 pm

dinof wrote: I bought one and tested my jeep and it scored steady needle in the green. Now I know my jeep is tuned perfectly, and it makes me feel great that I'm doing good mechanic skills, backed up by the VG.

And what about synchronizing multiple carbs? I remmeber something about that if I'm not correct. I'm a better mechanic with this by far.
That is exactly my point, No one needs a VG to find out their engine is good. Using a VG to find out why the engine is bad is a complete different story. People really using a VG on all kind of fault's find out pretty soon that all that blah blah about "the VG wonder tool that has been forgotten by most of us" is not a great help. Maybe it is good to go to your jeep and hook up your VG and introduce fault's. That is pretty easy and you will learn that the VG in most cases will betray you. Am not saying that it doesn't help in many cases but one needs to have a lot of experience and have a torough knowledge how an engine works. After you did that you definitelly will become a better mechanic!
Synchronising multiple carb's can be done with vacuum gages, but a workshop that does that job frequently like a Japanese motor bike shop are using mercury columns instead.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by artificer » Tue Jan 03, 2017 10:23 pm

Luc wrote:"the VG wonder tool that has been forgotten by most of us"
That is why Luc bought the best quality one possible.... was it 2009?....after telling all he'd never used one before. Now it is like he was using it in the '60's & found something better!
Since being bought it apparently hasn't worked as expected for him [but is working for others with limited but perseverance skills] so now it is forgotten? Give us all a break!
Last edited by artificer on Tue Jan 03, 2017 10:28 pm, edited 1 time in total.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by artificer » Tue Jan 03, 2017 10:31 pm

It is no wonder you get BANNED Luc!
You are nasty & vindictive.
No need to ruin my educational threads with your rhetoric.
Last edited by artificer on Tue Jan 03, 2017 10:32 pm, edited 1 time in total.
John GIBBINS Member Institute of Automotive Mechanical Engineers [Ret], ASE Master Medium/Heavy Truck & Auto Technician USA -2002 Licensed Motor Mech NSW MVIC 49593 Current 2015
TO DIAGNOSE, TROUBLESHOOT OR FAULT FIND ANY AUTO SYSTEM....
Understand how system parts interact with one another. GOOD parts can then be established & the NOT GOOD problem/s part/s isolated for repair or replacement.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Tue Jan 03, 2017 10:31 pm

artificer wrote:
Luc wrote:"the VG wonder tool that has been forgotten by most of us"
That is why Luc bought the best quality one possible.... was it 2009?....after telling all he'd never used one before.
Since then it apparently hasn't worked as expected for him [but is working for others with limited but perseverance skills] so now it is forgotten? Give us all a break!
I always buy the best quality tools as am realy using them and the VG is not catching dust in a drawer. I use it dailly for experimenting and finding air leaks in a fuel system. It would be good if you did the same John and than we can go further from here giving real and honest information to those not familiar with the trade. Perhaps buy a jeep in first instance as we are not interested in Mercedes 500SL's with brake booster's.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Tue Jan 03, 2017 10:32 pm

artificer wrote:It is no wonder you get BANNED Luc!
That's what an owlet does John, pushing others out the nest to install your very self.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Tue Jan 03, 2017 10:34 pm

artificer wrote:It is no wonder you get BANNED Luc!
You are nasty & vindictive.
No need to ruin my educational threads with your rhetoric.
First educate yourself John.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Tue Jan 03, 2017 10:45 pm

TonyStandefer wrote:I don't understand why there is any criticism of all this effort to help keep owners use a recognized diagnostic/tune up tool.

Instead of criticizing why don't you put forth the same effort at instruction/information. Using modern/available tools. Most of us don't have Joel's array of military diagnostic tools and must make do with Napa grade tools.

Full disclosure, I use a vacuum gave to tune my jeep. My high school auto mechanics teacher was an advocate of the vacuum gage. He even had one installed in the dash of his street rod.
That's what is happening here, we are discussing the Vacuum Gauge. Is there no room for a seccond opinion? Am using a VG dailly, and am trying to explain what to expect when using one.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by Tony W » Tue Jan 03, 2017 10:54 pm

You are a complete fool foxy.
And you are the laughing stock of the G 503 site.
I and many others hope this time you will be BANNED for life.
You are NOT welcome on this site , so why do you keep coming back.
You obviously have no other friends.
Tony
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chassis 259112
body 214625
engine MB131277 Overstamped XXX4B1945
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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by foxy » Wed Jan 04, 2017 2:28 am

Tony W wrote:You are a complete fool foxy.
And you are the laughing stock of the G 503 site.
I and many others hope this time you will be BANNED for life.
You are NOT welcome on this site , so why do you keep coming back.
You obviously have no other friends.
Tony
Thanks for your great contribution to this thread Tony.
I have copied and paste this and many other similar contributions from the past that might be handy one time.
I for one do not contribute throwing sh"t to people that disagree with me, on the other hand I continue to offer good advise to those that needs it.
Someone that think am wrong can just say so, I won't insult him.

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by Joe Gopan » Wed Jan 04, 2017 5:10 am

My suggestion is to have a timing light available for precise setting of the timing on the Jeep engine timing mark. Those who run out to purchase a vacuum Gage may not achieve the desired results due to inexperience or a cheap gage that is not sufficiently dampened for accurate needle interpretation. Some of those new to vacuum gauge will have to rely on uneducated guesswork and may indeed end up with their engine not timed correctly and not realize it.
The choice to time with Vacuum Gage or Timing Light is up to the individual and there are consequences if one cannot interpret the gage.
The Timing Light kit along with other diagnostic tools is basic to all Army Shops and accompanies convoys in the service vehicles. It is quick and accurate.
There is no need for those cheering for their Vacuum Gage method to reduce the topic to insults and name calling, decent members could see this coming.
Why not be professional and exchange ideas . Some of us have decades of Jeep experience, many of us got our start in excellent Army classrooms and motorpools or as instructors teaching Jeep as the Army intended it. Some are also professionally trained on the CJ's of years ago and and have much information to share as professionals with out the need for name calling and insults.

A hobby is supposed to be enjoyable, there is no need for any prejudice or hurt feelings.
2011 MVPA PIONEER AWARD - MVPA #1064
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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by dinof » Wed Jan 04, 2017 6:52 am

Hi Joel,
I used a vacuum gauge the other day on the jeep, and it backed up my tune was correct. Also, the gauge showed a steady needle indicating the condition of the valve train & other parts. So even if you don't use it as your primary tuning procedure, it checks and backs up the condition of the motor. Fair enough?

I have a Chevy V8 street rod with a Holley 1850 carburetor. The old way to perfect the idle was to adjust to the highest idle on a screw on both sides. It's a 1850 Holley so I figure you know what that is right? I'm going to use the VG gauge to get it better. I'll let you know. Funny thing, the Holley MFG site has a video on doing this and yes, they are using a VG to do it.
Dino Falabrino
On the "G" since 1998.
1943 GPW 102310 DOD 3-3-43
1928 Model A Roadster Pickup
1930 Model A Tudor
1968 Taco Minibike

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Re: Vacuum Tuning & Recently Advanced Vacuum Advance Fallaci

Post by Joe Gopan » Wed Jan 04, 2017 8:26 am

Have been fluent with vacuum gauge and timing lights for 60+ years both in civilian and military use and use one every time I adjust MV carburetors, If I can't get 18-22inches of vacuum the Vacuum Gauge is brought into play, it's SOP. Our new and used automobile business started up in 1945 with mechanics fluent with 1920''s and later cars. One of our early mechanics used to adjust the valves in 40's Chevrolets using a Vacuum Gauge. I used to balance the twin SU carbs on Volvo, Triumph, Morgan by inserting a piece of rubber tubing into the carburetors and listening, but that's another story. :wink:
No need to make an ugly issue out of auto technology as if it were never practiced before.
2011 MVPA PIONEER AWARD - MVPA #1064
HONOR GRAD-WHEELED VEHICLE MECHANIC SCHOOL 1960 - US ARMY ORDNANCE SCHOOL(MACHINIST) ABERDEEN PG 1962 - O-1 BIRD DOG CREWCHIEF - 300,000+TROUBLE FREE M-38A1 MILES
LIFE MEMBER AM LEGION-40/8-DAV
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COL. BRUNO BROOKS (ARMY MOTORS) IS MY HERO


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