85 CJ7 Overheating

[mlcl1985]

My jeep restore has become a huge project. It would not stay on even at just idle. The Carter BBD took a dump so I put in a rebuilt replacement. Then I found a few holes in the vacuum lines, so I replaced all vacuum hoses. While I was at it I replaced the PCV valve and grommets, along with a new EGR and O2 Sensor. Then my valve cover was cracked and leaking so I replaced the plastic one with a new aluminum cover. Thermostat housing was rotted away so that got replaced with a new 180 degree thermostat. Water was still leaking out of the water pump so I replaced that and the upper and lower radiator hose, and heater hose. No more water or oil leaking but now it is over heating. I adjusted the Carb to idle at 900 rpm any lower and it stalls. I checked the timing and set it to 8 btdc. It now starts up and runs and drives nice but overheats after idle no more than 10 mins. I did a radiator flush after replacing the thermostat housing, then another one when I did the water pump. Then I just did a third one before I put coolant in. I do not know how to cool it down at this point?

 

[hole]

You need to make sure you have the right rotation pump. Did it overheat before the WP swap?

 

[mlcl1985]

It did not over heat before. I bought the oem water pump

 

[mtnwhlr]

It did not over heat before. I bought the oem water pump

They have two different pumps depending what belt system you have. They turn different directions.

 

[Lumpy Grits]

Yup-Wrong impeller rotation is my bet here.
Are you run a serpentine belt? If so-pull the pump and look for an 'R' on the impeller.
Hope you kept the old WP for comparison.
BTW: Keep that BBD for parts, as it's the ONLY carb approved for SMOG in PRK.
Been much cheaper to have just rebuilt it.......
LG

 

[mlcl1985]

I didn't know that. I just looked at the carquest website at the part I bought. It says to make sure the rotation is correct. I threw the old on out already. How do I find out which direction is correct?

 

[mlcl1985]

Here are some pictures from when I replaced it

 

[mlcl1985]

I did a little research and mine is definitely wrong. I will try the reverse tomorrow and hope that fixed it.

 

[Lumpy Grits]

Take the other WP with you to the parts house and compare impellers.
Usually, the reverse rotation has 'R' stamped on the impeller.
You want the reverse rotation model WP...........
LG

 

[mlcl1985]

Problem solved, thank you very much. I changed it yesterday and it never went above half way on the gauge. I took it to smog today and it ran almost an hour and the temp was perfect. Unfortunately it did not pass smog. Even thought everything has been replaced.

 

[Lumpy Grits]

What part did you fail? I know they give you a print out.
Last year I had to put a new 'cat' in. Fourth one in 32 yrs.
LG

 

[Belizean]

LG it must be that expensive gas you're burning. I'm still only on my 2nd in 33 years. . Just got my inspection today also with no problems! It's a breeze here. Gas is almost back down to pre hurricane prices also

 

[mlcl1985]

It has an fuel evap leak. The HC and CO were both high but he said it's just because it's running rich. I just didn't know how to adjust the carb. I kept adding more air and it just kept turning leaner and meaner. I felt like it was not making and changes in the rpm so I turned them back in a little and stopped. So I am sure I can just do a few turns and lean it out to fix that problem. Just have to find the leak and it should be good

 

[mlcl1985]

Here's my results

 

[Lumpy Grits]

What do you mean-You keep adding more air?
Your stepper motor controls the fuel mix.
Just make sure both idle mix screws are turned out the EXACT same amount so the carb stays balanced.
Evap leak-Check the soldered section on the fuel sending unit on your gas tank. Several years ago I had the same thing, and traced it back to the sending unit and had to resolder the area where the metal tubes come through.

Belizean-Actually, it's the **** poor gas we have here that kills 'cats'. That and PRK tightened up the specs for my '85 in 2011. 'Cats' sold here now have a serial number on them like a gun does, and they are model specific.

Here is some good Carter info.
Moses Ludel's 4WD Mechanix Magazine - Rebuilding the Two-Barrel BBD Feedback Carburetor - Moses Ludel's 4WD Mechanix Magazine, HD Video Network and Forums

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LG