radiator cap

[stroker70]

I need a new radiator cap, so I hope someone can give me a couple part numbers for stant or whatever. Can I safely bump up the pressure from 7/8 pounds whatever it is to 13?  (1953 Dragon)

[joefrazer]

Stant makes a 7 lb cap that will work just fine on your Kaiser...I don't have the number handy. Most good parts stores carry them in stock so obtaining one shouldn't be difficult. Given that any KF OE radiator is at least 55 years old, I wouldn't mess with trying to bump the pressure much beyond the 7 lbs that the rad was originally designed for.

[GA Kaiser]

The '51 repair manual describes the cap as being a 4 psi cap.  The '52 and '53 supplement says the cooling system is the same as the '51, except the thermostat is a new design.  My '54 has a Stant 4 pound cap.  I just tried to buy a new one from NAPA, but the one they sold me was too tall and I could not install in on the radiator, but I will keep looking. 

[joefrazer]

I stand (or is that Stant...ha ha) corrected. Kaiser and Frazer cars used a 4 lb cap and the Stant number is 10208. That's for the cap with a 3/4" neck and will work for all but the early 47 cars that used the 1" neck rad. HJ and Darrins used a 7 lb cap. Somehow...I got 'em mixed up.
Hope that helps!!

P.S., if you want a cap with the flip up pressure release lever...not correct for judging but some folk like it...that part number is 10308.

[GA Kaiser]

Thanks for that info!  I will check into it.  It sure is great to be able to chat about this stuff with someone!  Nobody else in my neighborhood drives a Kaiser (imagine that!), so I have no one to talk to. 

With my new correct solid spark plug wires from Carl, my '54 is still running with the temperature gauge at about the 3/4 hot location after a tune up, timing adjustment, new t-stat, etc.  Is that normal?  Does anyone think it could be a problem with the water pump?  It does not boil over when I stop. 

[mbflemingkf]

I also have a 54 and put a single temperature gauge over in the extreme left corner under the dash so I could monitor the ACTUAL water temperature in my car.  If I have a problem, I want to be able to get off the road, etc. "BEFORE" it becomes a problem.  It was easy to install and takes the guesswork out of the 55+ year old gauges with pointers.

[joefrazer]

Where the temp sending unit mounts on a KF engine lends itself to readings that could be false. The water passages in a Kaiser head are not all that big so there could be some blockage that's causing slightly higher than normal readings. The easiest way to test is to bring the car to normal temp (in your case, 3/4 hot) and stick a meat thermometer into the radiator and see what it reads. Be careful when removing the cap, it's only 4 lbs but that's still more pressure than when the car is off and cool. The coolant can easily spray and burn you!

[GA Kaiser]

I am guessing that just leaving the cap off while it heats up will not allow it to reach as high a temperature, but I will try removing the cap the next chance I have to work on the car after a drive.  Thanks for the advice.  The remote temp gauge is also a great idea.  I know the gas gauge varies on whether I am sitting at idle or cruising down the road, too.  Now if I could only find some time for a cruise-in on a mild sunny day....! 

[HJ-ETEX]

The KF temp gauge is a King-Seely electric unit. There is a panel voltage regulator that is supposed to supply 5V to the unit. However, if you were to look at the gauge while the car is running and warm and then turn on the headlights, you might see the needle go down. When these cars were cheap used cars, it was typical for the owner to add a mechanical (capillary tube) water temp and mechanical oil pressure gauges. If you add an oil pressure gauge, it needs to be a 270 degree sweep type that has 5 psi as the 1st mark. Why? These aren't SB Chevy V8 engines and a hot idle oil pressure reading of between 5 & 10 psi is not uncommon.   

[GA Kaiser]

Should I just try a "cooler" spark plug?  I read elsewhere on the forum about the correct plugs for '54 and it's a bit confusing.  I have AC 45 in there right now, but the car seems to run better than ever.

[HJ-ETEX]

GA: Hot & Cold spark plugs have to do with how hot the electrode on the plug runs. It doesn't particularly have anything to do with how hot the engine coolant is. If you chose a plug that is too cold, it will tend to gas foul and the engine will be hard to start. If you have a spark plug that is too hot, it will tend to burn the electrode away fast. If we are talking about Yamaha 2 stroke motorcycles a hot plug could burn a hole in the top of the piston.
Well that isn't a problem with L-Head engines because the spark plug is located over the valves, not the piston.
But basically, if you don't drive the car often, you want a hot plug because it will be easier to start. If you drive the car a lot, then you want a colder plug.

[HJ-ETEX]

Another thought about hot & cold spark plugs. Around 1970 performance single cylinder 2 stroke motorcycles started having 2 or 3 plug holes in the cylinder heads. Well, the 1st hole is obvious, and the 2nd hole was for a compression brake. But the 3rd hole was for a second hotter spark plug. The idea was to have a hotter plug in the 3rd hole to easily start and warm up the engine. Then when it was time to compete, the rider switched the coil lead to #1 plug for racing.
The problem was hot & cold have to do with heat transfer. The 2nd, hotter plug ran hot even when it wasn't connected to the ignition system. So these guys burnt holes in their pistons even though the hot plug was not even firing.

[jerussel]

This has gotten a bit off 'radiator cap', but, on my '51 Frazer, I have both Auto-lite A5 and A7 plugs (NOS) available.
Which is hotter/colder?
There was a thread earlier about which plugs to use, but I can't remember the determination.  Any ideas?

[joefrazer]

The A5 plug is colder and was the original equipment plug in the early cars.