Vacuum Readings

[boatingbill]

The '51 Kaiser shop manual says to adjust the idle mixture jets for maximum vacuum readings using a vacuum gauge. It does not
say what a typical reading should be nor does it show a vacuum gauge and where it is connected. On the distributor advance
vacuum line, I read zero at idle, so where is the vacuum gauge connected and anyone have a ball park reading on a properly
adjusted carb ? My gas mileage is poor and this is a good place to start. I have already checked my timing.

[Doc]

Typically it is preferred to obtain a vacuum reading of 19-21" (sea level, will be lower at altitudes). The wiper vacuum line should suffice. 

[Doc]

https://www.google.com/search?q=engine+vacuum+readings&rlz=1T4GGHP_enUS524US525&tbm=isch&tbo=u&source=univ&sa=X&ei=kJgdVerHC8vDggSh-oG4CQ&ved=0CCwQsAQ&biw=887&bih=712

[boatingbill]

Doc: Thanks for the info, but I have electric wipers and I can't find another port on the carb. Maybe the Service Manual was
written before the electric wipers were available. Has anyone encountered this before ? I really want to use a vacuum gauge as
almost everything about the engine can be discerned from the readings. I went about 68 miles and burned about half a tank so
I'm guessing about 8-12 MPG at 60 MPH.

[joefrazer]

It could be that the vacuum line from the carb to the advance is plugged. Try installing another then connect your gauge and see if there's a reading. If not, the port could be blocked with carbon. My 48K had a blocked vacuum port...it took 2 days of soaking in solvent to clean everything out.

[boatingbill]

Joefrazer: If I rev the engine I get a vacuum reading of about 14 on the gauge. I then hooked the line back up to the distributor
and revved the engine and watched the distributor advance timing on my timing light, so that looks normal. I just have no vacuum
reading idle. If someone could hook up to the dist advance port on a 51-53 and see a reading, I will have something to go on. I
could buy another gauge if people get readings at idle.

[Doc]

There should be vacuum at that carburetor port at all times. When you rev the engine up and then let off the pedal, the vacuum should climb even as high as 23". I agree, the line or port must be blocked.

[rialto]

The vacuum advance on a Kaiser is normally connected to carburetor vacuum also called high speed vacuum.  The supply is above the throttle plate so no vacuum at idle. Rev the engine up and the faster the speed the stronger the vacuum. A vacuum gauge needs manifold vacuum right from the manifold. If you don't have vacuum wipers or power brakes there is probably a tapped hole in the intake with a pipe plug in it. Remove it and put a fitting in it with a vacuum nipple on it then you can hook up your gauge.

[dpledger]

The above comment is correct. Generally this port is on the back side of the carb bottom, and goes directly to the manifold. A plug screws into it. A bit hard to see, but can be located easily by feel. All other carb ports do not give true manifold vacuum under all conditions.

Be sure that all timing, dwell, etc issues are resolved before trying to set up the carb. Irregularities can greatly affect vacuum readings, and you will go berserk trying to maximize by adjusting the jets.

[boatingbill]

Dpledger: Thanks for the info. I did find the plug on the firewall side of the carb as you said. I can't get it out even soaking it with
PB Blaster, so I may remove remove the carb to prevent cracking the carb housing. Then I will try to soak it from the inside to see
if I can get it loose. Forget TV, KF products keep us active.