Resolving KF products Vapor Lock.

[boatingbill]

I would like to ask on this forum if the 53-55 Kaisers have vapor lock problems to the same
extent as earlier KF products. I know that KF products tend to be heat sensitive and the large
hood and smaller grille on the earlier products may contribute to that. My dad had a '53 for
16 years and never had vapor lock. There was a exhaust redesign in 53, so 53 Kaiser owners
do you have frequent vapor lock? I had 54 Kaisers with the smaller hood  and larger grille and
never had vapor lock either. So 54-55 Kaiser owners do you have vapor lock issues? My 51
Kaiser had frequent vapor lock with both Carter and AC fuel pumps. The 52 and earlier models
had a flap valve in the exhaust manifold that was to warm the intake manifold if the temp was
below 70 degrees. This was a fail-safe design with a counter weight to keep the flap valve
open heating the intake manifold until the heat sensitive spring warmed up and expanded
closing the valve. This type of design tends to corrode and stick in the open position causing
poor performance and vapor lock on warm/hot days. This type of design was common on
other cars too and at the gas station I was at we saw most cars that were a few years old
had this valve (heat riser) stuck in the heating position. So is vapor lock a very frustrating
issue for 52 and earlier models only? Maybe we can resolve this finally.

[joefrazer]

My 48 Kaiser would vapor lock in 70 degree weather.
My 50 Traveler has never vapor locked, even in 90 degree heat.
My 51 Kaiser would vapor lock, but not until I was in stop and go traffic on a very warm day.
My 53 Kaiser will vapor lock in any weather. To it's credit though, it does need a carb rebuild.
My 54 Kaiser has never vapor locked, even in stop and go traffic.
My 51 Jeepster...not enough travel time in that one to see if it'll vapor lock.

Now let's see what others have experienced!

[kaiservagabond]

This is an interesting subject.  First I owned a '49 Vagabond for about7 years from 91 thru 98 and never had a vapor lock on it. But I had a '53 Manhattan from '89 to 95, lost it a fire in my garage in Apr 95, and it had a bad vapor lock problem.  So every time I would stop, any where I would raise the hood to let the heat out.  But even then if one was to put his hand on the carburetor bowl right after raising the hood. you would burn your had because it was so hot.  My solution was that if it sat for about 20 minutes when I went to start it again I would slowly push the gas pedal to the floor and hold it while cranking the engine.  It would then start and dump black smoke out the tail pipe.  As I wondered why it was doing this I raised the hood one time removed the air breather and looked down the top of the carburetor and saw it was simply just dumping raw fuel into the intake manifold.  My car was a later model and had the fuel line from the tank to the pump routed around the #1 cross member instead of the #2.  I never did install an electric pump on it because that was the only time it would vapor lock.  However, to go a little further when I got the 53 Dragon, and was detailing the engine, I split the manifolds and as an experiment I reduced the 2 holes in the exhaust manifold from about 1/2" to 3/16" and it helped.  I thought of going back in and plugging the holds completely but never did as it had an electric pump on it when I bought.   However, when I would be in traffic it would vapor lock so I always, when coming into a congested area would turn on the pump and it would eliminate any lock.  (Now mind you I'd also set the mechanical pump pressure @ 4psi. but din't have to use a pressure regulateor for the electrisc pum. A friend of mine had a '51 K and one time we were going to Enid, Ok and we had to make a pit stop , if you will, and he told me not to leave until he got his car started because he said it would vapor lock.  So when we stopped I immediately  raised the hood on his car and we spent about 25 minutes at the station.  Then when he came out I told him to hold the pedal all the way down until the engine started, and it started right up and he said it had never done that before.
As for heat riser on the  cars prior to "53 they were supposed to be lubricated periodically but most never did  get lubed.  I lube the one on my 50 model each time that I change the oil.  No problems.

Hope this will be of some  helps.

Richard

[rialto]

There are two seperate problems being discussed here. Classic vapor lock is where fuel vaporizes in the line or pump due to high underhood temperature.Then the pump cant pump wind,car dies untill it cools off. This is a fuel starving condition. This can happen when running or during a hot start.  The other problem, I believe is called fuel percolation. Fuel boils and expands in the carb or line after the pump. This is a flooding condition. This happens on a hot start. Both are caused by high temperture and are aggravated by todays gas.

[kaiservagabond]

I cetainly agree RIALTO with your comments.  However, either one can and will be very frustrating.
Richard

[Doc]

'54 Manhattan did have severe vapor lock problems in high heat of August (mid 90s) EVEN with an electric fuel pump running continuously.  Since I rerouted the well away from the exhaust manifold, I did not have any further problems and have not had to activate the electirc pump which is now toggled.  '54 Early Special has had significant problems as well even on shorter trips (one ~ 35 miles and another less than 10 miles, again on very hot August days. Electric pump saved the day on the Early Special both times. In none of these cases was the engine coolant temperture ever in the danger zone.

[Tom N]

See Also "Electric Fuel Pump" discussion

[G.B. (All Vinyl Dragon)]

I heard putting a close pin on the Fuel line in front of Carburetor fuel line in, prevents Vapor Lock This was told to Me the other Day by a Vintage Car Mechanic.

I have a electric Fuel pump on mine under the frame. You can prime & start it like You drive it every Day.
It also can be used on Hot Day's(Vapor Lock). You can turn E. Pump on & get started, then get up to 30 MPH & turn it Off & go on down the road.

[pnw_oldmags]

Clothes pin for vapor lock is an old wives tale in my opinion.  Tried 1 then 5 the 10 ... no positive results

[kaiserfrazerlibrary]

Water temperature is not necessarily the issue on the vapor lock.  First, gas evaporates at a lower temperature than ever before and the "boiling point" will drop further once the EPA's change to 15% alcohol mix (they think only of cars being built in the future not older vehicles, farm tractors, etc and the problems they may have-that goes back to the late 1970's when lead was removed from gas).  Second, there is the air temperature within the engine compartment...the early Kaiser and Frazer cars (with blocks that have the fuel pump in the rear instead of front) are especially prone to the condition becuase of the heat that traps in the back of the area if the car is not moving (and the air does not move out under the floor because there is no "wind" created by car movement).   All kinds of cars, including newer vehicles are suffering from vapor lock now, even though they had no problems just a few years ago.  It will only get worse as time goes on.

If you go through the various factory shop manuals and parts books, you will see how the fuel line was moved around, especially in 1953 to expose more of it to the cooler air hitting it before the carb.  This was done to help reduce temp of the gas so it would not boil off (creating the vapor lock).