3B Project

[Reserector [Veteran Member]]

Well, then. I guess I won't be driving it. LOL

[81 CJ5]

Got the wiring cleaned up and hand sanded all the parts of the roll cage where I never painted and it had rusted (engine bay too). Cut out a new larger diameter dashbar. Finally got the push I needed to cobble together a tunnel cover. I started with a cardboard template, picked up a piece of 24x16 20 gauge cold roll for $10, then started cutting and bending where needed. I was given this sheet metal brake/shear/roller and it came in handy for this little project. Threw on the sidebars to make sure they fit after cooling off. I'm finally almost done. The only things left are exhaust, driveshaft loops, alignment, and still waiting for my title to show up.

[81 CJ5]

I have a wheel that keeps losing air so I decided to fix it.



The RV2 was sorta tight but it managed to fit. I made a bracket that goes from a valve cover stud to the compressor head and then cut and reused the entire front compressor bracket to hold it to the power steering pump mount. There is another bracket on the back of the compressor that was made from an old shackle that was bent and cut to fit on a cylinder head bolt. I got the pulley from my local farm supply and reused the old compressor rear mount to hold it. This all worked out very well and the compressor works too. No belt squeal either.




Went for a drive afterward. The overheating issue is still there. Every single fhead powered jeep I've owned had overheating problems and I don't know why. Does great putting around but drive high speeds and the temperature climbs fast. 

[fun in dirt [Veteran Member]]

Went for a drive afterward. The overheating issue is still there. Every single fhead powered jeep I've owned had overheating problems and I don't know why. Does great putting around but drive high speeds and the temperature climbs fast.

Overheating issues can be a pain to track down.  We went through this for months with my husband's Chevelle years ago & it ended up being a brand new water pump that was bad. No idea about Jeep setups, but here are some ideas of things to check...
Do you have a fan shroud to help direct airflow?
What about the fan clutch condition?
Both radiator hoses hot/pressurized? [like pump moving water (impeller doing it's thing) through radiator(not stopped up)]
Coolant/water mixture good?
Good luck!

[Reserector [Veteran Member]]

If High speeds are the issue, my guess is that air flow is not the problem.
What's left? Coolant flow, as fun in dirt mentioned and/or radiator size. That is assuming your mix is good, as fun in dirt pointed out.

I had to replace my Nissan radiator once as a last resort, even after flushing, etc. It was not clogged or anything. However, once I replaced it, my overheating stopped. I guess it was calcified or something. Not transferring enough heat.

[81 CJ5]

No bubbles in the radiator while running, no milky oil, no major leaks (radiator has coolant droplets on the bottom of it), the temperature gauge is accurate and tested against another gauge, the temp. gauge probe is installed in the rear of the cylinder head. I added a bypass to the cylinder head and there's another hose to bypass the would be heater core. New water pump, the fan belt is tight, the fan is facing the way it should. The timing isn't too far advanced. New 160*f thermostat tested in boiling water, it opens and closes as it should, and I drilled a 1/8 hole in it to help with bleeding the system. I have flushed the engine block and radiator separately twice and the coolant is clean. I'm running a 50/50 pre mix coolant. New radiator hoses and they don't appear to be collapsing. The radiator was taken to a shop and they soldered and cleaned it, they also tested the cap and said it was good. I don't have a fan shroud but the fan is ~1 3/4" or less away from the radiator and I can feel it pulling air from the grill. It doesn't boil over even at 220*f on the gauge. Driving around slow is fine but as soon as you get moving down the road at higher speeds (35 mph+) the temperature starts to climb fast.

I bought a new 3 core aluminum radiator for it. Should be here Wednesday. I also did a combustion leak test on the coolant system and it passed that. Fan belt is tight and I pulled the upper hose and watched as the thermostat opened and coolant gushed out so the water pump does move coolant.

My safety net stuff came in today. We're almost ready for the Miler.

[Reserector [Veteran Member]]

Might just be the radiator not transferring heat anymore.

[81 CJ5]

The new radiator arrived this afternoon. Should be better than the old copper/brass unit. It's a 3 row radiator. Even if it doesn't fix the issue it will be much better than what I had before. 



The tubes on the old one were nasty. 




I had an M38A1 fan (left) and a civvy fan. They are different apparently. I installed the A1 fan to see if it moves more air. 



I made the radiator mounts out of 3/8" plate. I plan on replacing the old temp gauge with an autometer one I tested and it seemed to read accurately. 

[Reserector [Veteran Member]]

Sweet radiator!

[81 CJ5]

Looks like the new radiator fixed the problem. 13 miles of hard driving and it didn't overheat so I'm convinced the issue is resolved. I also wired up a horn.