now i can't keep up with traffic

i think i finally figured it out!!

i had driven it until it did the whole 'losing power' thing, then brought it home, and popped the front wheels off to test fit some new KH wheels and figure out what spacer i needed to clear the front discs. so i jacked up the front and the wheels wouldn't spin. at all. so this gets me thinking that the brakes are messed up, mad, so i call up the local Jeep shop, and start asking questions before i tear into it. well it turns out that the guy there was having the *exact* same problem with a Jeep he currently has in the shop, and here's what he thinks it is:

the original drum brake system needs something like 10lbs. back pressure to keep everything in check, but the system that the discs came off of (a mid 80's cj) only needs around 2lbs. back pressure. so what's happening is the master cylinder is keeping too much pressure in the front lines, which applies the brakes even if your foot is off the pedal. this then snowballs, and because there's too much pressure in the front lines, it fluid heats up and expands, thus causing even more pressure, which applies the brakes further. (this doesn't affect the rear brakes, as they are still drums, needing the original 10lbs. back pressure.) eventually, this friction overcomes the what the engine can handle, and the 'loss of power' that i was experiencing happens.

so.....he's working on re-valving the master cylinder so that the front discs get the 2lbs. pressure they need, while the rear drums get the 10lbs. that they need. hopefully [fingers crossed] this will fix the problem.

 

If you are using the stock master cylinder and disk brakes, you have to drill a hole in the tin mushroom shaped thing that kinda looks like a salt shaker lid in the master cylinder. It will then allow fluid back int the master cylinder reservoir so the pads don't drag. Donny at Mile High Jeep Rebuilders in Denver told me about this trick.

 

They should know, I still drive the 60 mi to get parts from them if needed.
First trip was in 1972.

 

awesome. thanks guys

 

your right, but your also wrong. The f and l heads are 1-3-4-2 firing order. if you are 180 out TDC on the flywheel would be # 2 cylinder. Slap the sensor on # 2 wire and time like normal with the light.

an easier way of doing this is finding the 5 degree mark on the flywheel and taking whit out and making corresponding marks on the timing cover and crank pulley. Take you timing light and line up the marks while turning the distributor. easier than tuning by ear and a lot more exact.

 

I had a 74 with a 304 in it set me into a fit ,, replaced the rad, new fan , new therastat went from 180 to 160 ,, Still over heated I noticed the water on top on the rad wasn't moving so I pulled it all down again & yanked the water pump that was not leaking or wobbly and the propeler was lose on the shaft,, when it was idling it would grab hold & cool ,,anything over 1K it would slip.. Took some wet paper towels rapped the shaft under the propeller & tack welded it to the shaft ,, worked fine after it was put back togeather,,, GOD you gotta luve these JEEPs R)

 

I know I'm late here, but take a look at my thread. I was having the same problems, but fortunately my front disc brakes were dragging so bad I took a ride around the block and when I got home I could smell them and knew something was up.

http://www.earlycj5.com/forums/showthread.php?t=66177

If you have any questions, just let us know. I'm glad to say my brake conversion is finally done and they are actually working properly now...