F134 Oil Cooler Question.

How do I ask a question on this site? I need to know if it is a good idea to install a sandwich style oil cooler adapter on my 1970 CJ5 with a Willys 134F. It is getting hot here in NC. Please help.

 

Agreeing with Howard... If you have cooling problems, I would first look at the condition of the radiator. An oil cooler seems like an exotic addition without any obvious benefits over the existing cooling system. If I could not bring the original radiator up to spec by repair or recore or if it were too expensive to replace, I would look to a replacement aluminum radiator - lots of different shapes and sizes are available, targeted at the hot rod market.

I would also make sure my gauges were giving me an accurate reading of the water temperature and oil pressure (OP). If your oil is overheated, it will get thinner and the OP will drop. Check the OP on a cool morning with the engine up to full operating temperature, then compare to the pressure you get on a hot afternoon. If the temp gauge is the same and there's no obvious difference in OP, an oil cooler won't make much difference. You could also add an engine oil temperature gauge to read the oil temperature directly, but I think the oil pressure will give you an indicatiion of what's going on without the extra gauge.

 

I have a new radiator from Auto Zone. It is made for a 2004 jeep 4.0L. That was the only other Jeep available to measure and it fit fine. No oil pressure gauge but I would like to install one. Where on the 134F should I put the sending unit? Where should I put an oil temp sending unit? New water pump. New 160 degree thermostat with a small hole drilled in it. New exhaust. Flushed the block 2 times with fresh water. I am hesitant to use a chemical flush on a 46 year old engine even if it only has 60K miles. It runs great with good compression on all cylinders. Petronix ignition. No boil over problems. The factory temp gauge in the speedometer normally shows a little lower than the half. Lately it runs a little above the half mark. Temperature here has been around 100 degrees 50% humidity during most of the day. It is in the low 90's by 9am. I drive the Jeep every where almost every day. I use ethanol free fuel. When I leave work I cover the under seat fuel tank with a towel and dump about 2 gallons of refrigerated water over it to help prevent vapor lock, a problem I fought for a few days until I figured it out. New stock mechanical fuel pump. New carburetor. New fuel lines. Any help would be welcome. Did I mention it is hot here. Thanks.

 

Vapor lock is not often seen as a concern with F-heads, if ever. Thye were designed and built to serve the military in every part of the world, after all.

What "new carb" do you have?

Is it possible the in-tank filter is partially blocked? The only part of the system subject to vapor lock would be on the suction side of the pump.

 

If you are worried about temperature, I'd suggest you add a temperature gauge that reads in degrees. The thermostat will keep the temperature close to its set point (here 160), but you should expect the temperature to move up or down a little with engine load and air temperature. This is just a characteristic of negative feedback systems with finite gain (like thermostats).

A cooling system needs excess capacity for cooling. This is basically the ceiling of the system. The thermostat keeps the temperature near the set point until the ceiling is reached. From then on, the thermostat is wide open and the outside conditions and engine load control the temperature. If you always go above the ceiling in hot weather, then you don't have enough cooling capacity. You need to know the coolant temperature in degrees. Infrared laser thermometers are pretty cheap Amazon.com: Etekcity Lasergrip 1080 Non-contact Digital Laser Infrared Thermometer, Yellow and Black: Home Improvement - see what the temperature is at the thermostat housing and at the radiator. Regarding a 160 instead of say a 180 thermostat, it does not affect your cooling capacity, and is pointless if a 180 is what the factory uses. I would check what thermostat the service manual recommends and use that. The hole in your thermostat plate lets air bubbles escape, but flow through the hole reduces the thermostat gain, making the operating temperature neighborhood around the set point larger.

I would not hesitate to flush the block because it's old. Not sure what's available today for this, but in the old days you'd use a two-part kit of chemicals and the Prestone Flush N' Fill kit. Lots of articles on the internet about how to flush.

I'd also get an oil pressure gauge. Oil pressure will tell you a lot about what's going on in your engine.

 

Wasn't aware of a filter in the under seat tank. ???? Vapor lock was occurring in the line to the fuel pump. Solex carb. The biggest help in curing the problem was the switch to ethanol free fuel. Just ordered a water temp gauge from Kaiser Willeys. Where should i put the sending units for the water, oil temp? I have severel different laser temp gauges. What should the temp be? I will be constructing a better fitting fan shroud this weekend and i will take some photos and post them by Sunday. Thanks for the help. Be back soon.

 

I'd install an oil pressure gauge way before an oil temperature gauge.

What temperature? 160 at the thermostat housing. Pretty sure coolant travels from bottom to top in the radiator. So a little hotter coming back from the block and cooler leaving. Should not be a lot of difference. The coolant circulation mixes the temperatures as well as bringing the heat to the radiator. Just measure a bunch of places at idle in the shade with the engine up to full operating temperature, and then go for a drive. See what the temperature differences are.

 

The militaries have one for sure, but so do most other vehicles.
But as far as the stock Cj5 tank goes, I was just having a Senior Moment. I don't remember ever opening one up, although I may have.

My '56 is definitely getting plugged at the tank end in any case. Every so often it stalls on a high speed uphill. I disconnect the line at the pump and blow it back, and it runs okay again for a while.

Drained it once, and fished a lot of crap with a magnet. But I guess I need to open it up and take a look-see.

 

A quick word on vapor lock. I only have a few minutes. You are correct, in the old days vapor lock was not likely a problem for these jeeps. In my research on my previous problem I discovered a few facts about gasoline. The vapor point of ethanol blended fuel can be up to 70% lower than non ethanol fuel. In my area the pumps are labeled: MAY CONTAIN UP TO 10% ETHANOL. There is no enforcement of this. Some unscrupulous retailers have been known to blend their fuels with up to 30% ethanol. This drastically lowers the vapor point. There are other factors to consider however. Fuel pressure is also a factor in the vapor point of fuel. The higher the pressure the higher the vapor point. That is why most newer vehicles don't have a problem. The fuel pressures are much higher with modern fuel injection systems. Even my lawn mower is fuel injected. The surface temp of my under seat fuel tank was 89% after a day in the sun. That and the fact I was only holding 3 gallons on this day led to my vapor lock problem. ( New tank, new hard lines, new fuel pump, new solex carb, new vented fuel cap. ) The lines are routed as they were from the factory Which is not ideal because they run parallel to the new exhaust. I did however insulate them. My vapor lock problem was on the inlet side of the fuel pump. I could see it. Fuel coming in was foaming. But that problem is history. Largely cured by the NON ethanol fuel.

Now what about my original question????? Does anyone have any experience with a sandwich style OIL COOLER?????

 

external cheapy coolers are a great way to add one more level of oops to a rather robust engine that can run stationary for hours.

 

Run stationary for hours......hummm. I guess i will put my oil cooler stuff back on the shelf for now and move forward with other tasks. I will still post some pictures on Sunday. I will also add an oil pressure gauge very soon. Thanks to every one.

 

Well yes, but the key point about modern vehicles is more that they are pushing the fuel, with in-tank pumps, not pulling it with suction from an engine mounted pump. The '34 Ford V8s are notorious for vapor locking, and one cure is a low pressure pump, mounted in the tank.

However we've had 10% ethanol here for years and I've never had a vapor lock on my '34 - or any jeep.