The Stovebolt Site Forums The Shop Area Engine Shop 235 Running hot...

Hello all, I have researched and searched the forums for answers to my running warm condition, to no avail.

Background Info for consideration:

-1954 235

-overhauled in 2007 now has about 7,000 miles on the motor. (runs very strong)

-"rv cam" I believe a 261 cam

-Dual carbs (Webers) Langdon setup

-Dual fenton exhaust

-Electronic ignition Langdon (advanced 13 degrees at idle as instructed)

-new 4 core radiator running 50/50 water green coolant

-new 165 thermostat

-7 lbs radiator cap

-Electric fan in front of condenser

-Old air products AC

-12v alternator

I added an electric Tach and temperature gauge hidden in glove box. The temperature runs anywhere from 200-220 degrees. The probe is located in the original placement. I changed the radiator, thermostat and hoses with no decrease in temperature.

This morning I timed how long the motor takes to get the motor up to temperature. The Outside air temperature was about 90 degrees. With the motor at idle it took the motor about 10 minutes to heat up to 200ish degrees.

When I sped the motor up (2000 rpms) the temperature would decrease slightly (10 degrees).

Does anyone have an idea of what could be causing the motor to run hot?

What should I check next? water pump?

I read on the forums about a possible head gasket failure, allowing exhaust to heat the water. What indication would I see, beyond the excess temperature, before pulling the head?

Thanks in advanced!!

Simple test------ pull the radiator cap and look for bubbles in the coolant. CAUTION........... do not take it off at temperature remove it before the engine warms up. I know you knew this already but safety first.

Never assume ANYTHING for me, hahaha. I'll give it a look!

Thanks!

I am assuming that your temp gauge in the glove box is aftermarket. Given that you have no driveability issues, and revving up to 2,000 RPM reduces the temperature by 10 degrees, I would suspect that your gauge is not accurate. If you had a serious engine issue causing it to run hot, I do not think that revving the engine would cause it to cool down.
Carl

I've double checked the temperature with a infrared thermometer. It seems to be accurate.

If it's not boiling it's not running hot. With the 7# cap it would have to run close to 240 before the coolant would boil. The condenser and the electric fan are restricting the airflow enough to make the temperature climb a little- - - -get used to it. Your cooling system is running at normal temperature for a similar system in any other air conditioned vehicle.
Jerry

So, if there is no bubbles in the coolant, it's ok to run at 220ish? It's never boiled over etc.

That's the reason for a pressure cap- - -every pound of pressure raises the boiling point 3 degrees. Was the engine built with modern aluminum pistons? They're manufactured with expansion-limiting struts to keep them from tightening up and dragging at higher temps. Does the engine start when it's hot without the cranking speed being abnormally slow? If so, you don't have an overheat problem.
Jerry

Ok, It starts right up when hot. The reason it bothers me is, I'm having vapor lock issues. If I go somewhere and turn the motor off for 20 minutes or so, after I drive a block or so, it'll die. I'll have to pour fuel down the throat of the carbs to get it running again. It's a pain in the rear, to say the least! I really prefer not to add an electric boost pump, but I may. Any suggestions?

You might want to back off the timing at idle from the "as instructed" directions. A few too many degrees of advance is way worse than a whole bunch of too many degrees retarded (as preached by HRL).
If nothing works to solve the hot soak, no start scenario, I would recommend using an electric fuel pump with a pressure regulator which has a return line to handle the excess fuel back to the tank in a separate line. This will keep a constant flow of gas through the lines, keeping it much cooler. You can run it through the existing mechanical fuel pump without issue, or use a fuel pump block-off plate and eliminate the mechanical fuel pump.
I like the idea of not including the mechanical pump due to concerns of the possibility of the diaphragm springing a leak and having the electric pump filling the crankcase with gas.
Carl

Do a pressure and volume check on your fuel pump. Disconnect the fuel line at the carburetor, deadhead it into a 0-10 Lb. pressure gauge and start the engine. The fuel pressure should be 3-5 PSI, and should stay up for several seconds after shutting the engine off. Then connect a vacuum gauge to the inlet side of the pump after disconnecting the fuel line from the frame. Run the engine. The vacuum should be 10 inches of mercury or more, and should remain for about the same time as the pressure after shutdown. Reconnect the inlet line and route the outlet into an empty oil bottle or other 1-qt. container. Idle the engine for 30 seconds on the fuel in the float bowl. The pump should produce at least a pint of fuel in 30 seconds at idle. Be sure to vacuum check the flex line between the pump and the frame- - -sometimes a flex line with a pinhole can suck air without leaking fuel.

Failing either the pressure or vacuum test means you have a bad fuel pump. If it passes the pressure/vacuum test and won't pump a pint of fuel at idle, you have a restriction in the fuel line from the tank to the pump or a restricted pickup tube in the tank. Unless there are very unusual circumstances happening, "Vapor lock" is about as much of a myth as Santa Claus or the Easter Bunny!
Jerry

HRL, I forgot to mention I added a fuel pressure gauge after my last "stall". It reads about 4 PSI at idle. After I added the pressure gauge I tried to simulate the "stalling" scenario in my driveway. I took Ol' Blue on a drive around town and noted the fuel pressure prior to shutdown (4psi) I parked it in the sun and talked to my neighbor for about 20 minutes. When I restarted the motor, the fuel pressure gauge indicated 0 psi. I opted to stay in the driveway versus driving on the street. I left the motor at idle with 0 psi fuel pressure but, the motor continued to run. color me completely confused after this experiment.

On another note, that may or may not matter, I have a dual action fuel pump. It's not needed, as I went with electric wipers after my rewire.

I think my next step will be an electric pump with a return line. Any recommendations on a setup?

Run, do not walk away from an electric pump! It's totally unnecessary, and unless you wire it through an oil pressure sensing switch, it's an extreme fire hazard from flooding if the engine happens to stall and the pump keeps running. If you're going to replace the pump anyway, buy a Carter pump and forget about fuel supply problems. Like with their carburetors, "The ABC's of carburetion (and fuel pumps) is Always Buy Carter!"
Jerry

Ok, is this what they sell at Classic Parts? I'm going to check the vacuum tomorrow on the inlet and the volume check.

Thanks for the help

I'm not familiar with the Classic Parts inventory, but Carter has been making top quality fuel pumps for the 60-something years I've been pulling wrenches, and they were always my "go to" option when fuel supply problems cropped up. The really frustrating ones were Flathead Ford V8's with about a 14" lift from the tank to the fuel pump because the pump was mounted right on top of the engine, and it was in a very hot spot. Those engines were notorious for stalling due to "vapor lock" which was simply caused by a fuel pump that couldn't develop enough pressure and volume to keep the gas liquid. Ford pumps just couldn't keep the vacuum side of the pump working well, (bad check valves) and a Carter pump always solved the problem.

The Carter part number for a single-acting mechanical pump for a 235 is M-2118. Summit Racing has it listed for $41.00, so don't let some specialty parts dealer bend you over a barrel on price!
Jerry

I put an order in to Summit today so, hopefully I'll have a new pump installed soon. Thanks for the info!

Dont buy the carter m-2118. you pay the extra bucks and its still a airtex cheap pump in a carter box. i bought 2 and thats what i got. Just go get an airtex one over the counter at any loacl shop. both of mine were actually stamped with the airtex number.

I called summit racing on this after getting them in the mail and they even said that's what carted does with almost all of the pumps they sell under the carter name.

does putting fuel down its throat always fix the issue? or does it at time still stumble like its running on one carb?

reason why i ask is mine did this for a bit after installing the first and second set of toms carbs. I had debris in the bowls and jets that would work its way up and stop it from running just like that in traffic. Its the debris from when he punches holes in the tops of the carbs to vent the bowls. Both times i thoroughly cleaned them i found the same metal bits stuck in passage ways. BLOW THE LIVING CRAP OUT OF THE JETS as they sit installed with a air gun after removing the top half of the carb. Put a rag over the rest so the fuel does not shoot up at you and you also might find some metal chips when finished.

Hmmmm- - - - -bad news about Carter pulling a stunt like that! So much for another company living off what used to be a reputation for good quality American-made products! Back when I signed on as training director for the Sun Electric Co. distributor in Nashville, I found out pretty quickly why Sun was having a sales slump. Within a couple of months, they almost went bankrupt, and the training department nationwide, along with my job, bit the dust! Just a little after that, Snap-On bought Sun and restructured the whole company!
Jerry

Hotrod, I bought the fuel pump you recommended and installed it today. It seems to be putting out a little more pressure. It also showed pressure much more quickly on startup. I shut it down and went inside for about 30 minutes and it still had residual pressure. So, I think this should help my situation. Thanks everyone for the help!!

Glad it seems to be helping- - - -I've seen low fuel pressure and/or pressure bleed-down cause that sort of problem quite often.
Jerry