Engine Swap for 1953 CJ3B

Hi everyone,

I have been looking into doing an engine swap on my 53 CJ3B. I currently have a rebuilt hurricane engine in it. I would like keep the T90 transmission as it is in very good shape, but wondering what my options would be for an engine swap. Are there any 4 or 6 cylinder engines that are a basic swap without too modifications to make the transmission fit the engine? I understand that it may be changing from a 6 volt to 12 volt, but would like to know if there is a fairly simple engine swap for this jeep and year.

Thanks for the help!

have seen old jeeps that have had the old chevy 283 dropped in it,,,pretty potent, IMHO too potent for the frame

Quote:

---

Originally Posted by tswaim

Hi everyone,

I have been looking into doing an engine swap on my 53 CJ3B. I currently have a rebuilt hurricane engine in it. I would like keep the T90 transmission as it is in very good shape, but wondering what my options would be for an engine swap. Are there any 4 or 6 cylinder engines that are a basic swap without too modifications to make the transmission fit the engine? I understand that it may be changing from a 6 volt to 12 volt, but would like to know if there is a fairly simple engine swap for this jeep and year.

Thanks for the help!

---

The little V6 engines drop in fairly well, but remember that the rear end gearing is still going to be for the Hurricane - probably a pretty high number (5.38 for my '48 2WD). You'll run 2700 RPM at 45 - 50 MPH. If you're going to swap an engine, look at changing rear end gear ratios to match the new engine.

Thank you both for the input. Greatly appreciated.

Is anyone familiar with the 2 barrel carburetor's? I have had a full engine rebuild on my hurricane, a new engine pump, new fuel lines, new gas tank, but for whatever reason the jeep is so unreliable. Sometimes it fires right up, other times it won't start. Its almost as if its not getting gas. Sometimes I need full choke to start it, others it needs nothing. I am trying to figure out what the perfect combination is to start, but beginning to think something is wrong with the carburetor. Do the carter carburetors go bad at any point? This is an original and I don't believe has had a rebuild. When starting, should you need choke?

Thanks,
Tyler

A. Is anyone familiar with the 2 barrel carburetor's? I have had a full engine rebuild on my hurricane ...

You ask about the 2-barrel carburetors. I don't like to say that "Willys never..." did anything, but most Hurricane F-134's had Carter YF single barrel carburetors.

B. Do the carter carburetors go bad at any point? This is an original and I don't believe has had a rebuild.

Yes, Carter carburetors, like just about anything that has been around since 1953 or so can develop problems. Dirt and rust can get into the carb, and that causes issues with little ports and passages. Eventually the accelerator pump diaphragm will develop a split or crack, making it much less efficient. Floats can stick, inlet needle valves get dirt in them or develop worn seats.

Go to the CJ-3 page and look at the article "A Tale of Two Carbs, Parts 1 and 2" by Dave Pete for everything you ever would want to know about Carter YF's. They're really very simple units. Don't swap parts just because they are new and shiny!

C. When starting, should you need choke?

It's not uncommon to need some choke, but full choke isn't usually needed.

D. Just for giggles, check the condenser. In my rebuilt distributor, new from a vendor, I ended up with a condenser that had a loose strap - not connected to the case at all! If it made contact, almost instant start. If it had jiggled loose, very hard start - lots of choke and it smelled like it was running very rich when, in fact, it just wasn't burning fuel. If it jiggled loose while you were running - pull over and call the flatbed to get you.

We had an "old guy" tell us we had a bad condenser. We had driven Mike at KW crazy with carb questions and we finally were convincing ourselves it wasn't carb. Of course we had all kind of reasons that it couldn't be a bad condenser. The "old guy" just said "If you want to argue, go ahead. If you want the truck to run, replace the condenser". That's when we found the condenser with no ground connection thru the strap.

The old guy was right - it's started every time since then.

Good luck - let us know what you find. Someone else has the same problem - they're just not asking.

This is extremely helpful! I will give the replacing the condenser a try. Thank you very much for your help!

I will let you know what I find out.

My 53 CJ3B has a 283 in it. I didnt do it I bought it that way and yes even with a 4 spd tranny in it the gears keep it to around 40 to 45 mph. I am probably going to look at redoing the gears or swapping out the rearend.

Quote:

---

Originally Posted by steven121972

My 53 CJ3B has a 283 in it. I didnt do it I bought it that way and yes even with a 4 spd tranny in it the gears keep it to around 40 to 45 mph. I am probably going to look at redoing the gears or swapping out the rearend.

---

For the great majority of transmissions, whether 3,4 or 5 speed, the highest gear is a 1:1 gear. (Overdrives don't count...). For every revolution of the engine, the drive shaft turns once. If the CJ3B has a 5.38:1 rear-end, it takes 5.38 turns of the drive shaft to turn the rear wheels one turn. A bigger engine will change low end torque, but unless the differential gear ratios are changed, it will still scream to get up to 65 MPH.

Out of curiosity, I ran the numbers for the '48 2WD with 6.50 x 16 tires. I set my top end cruise at 2700 RPM (cautious), and it came out to be about 45 MPH as my cruise speed. That's what Jeeps do. They give you time to appreciate the scenery. As a quick guess, 65 MPH cruise would take about 3900 RPM.

Thank you for that info, very helpful. I will most likely leave it as is. All I have left to do is get the brakes working right, that a headache for now.