Auto Tranny Not Shifting after New Heads

[bslagle]

Over the last few weeks I have rebuilt the upper half of my 1991 EB Ex (new heads, gaskets, valves, springs, cleaned and replaced anything questionalble) and now the tranny wont shift unless its at WOT. The transmission was shifting smoothly before the rebuild, I think it was replaced before I got it. I have heard that there is a "kick down cable" for the transmission that may need adjusting. Where is this cable located and how do you adjust it. Any help will be great.

 

[410Fortune]

on a 91 Explorer the kick down cable attaches to the top of your gas pedal, right next to the throttle cable.
The adjustment is where the cable goes through the firewall, you push down on the white button and pull the cable out (towards the engine). Then all thats needed to adjust it is to depress the gas pedal to the floor, it will click into place.

However your problem sounds more like the vacuum line to the transmission then the kick down adjustment.

 

[bslagle]

Thanks for the advice, im going to take a look at it when I get home....I also have a another hose to replace (heater hose) but I dont think that would effect the tranny. How could I tell the difference, and where would the vacuume line connect. I dont know if i got all the vacuume lines correct, so many of them! Is it a thick hose or small one and from where to where does it connect.

 

[sneeedle]

Hi I am posting this for bslagle as he does not have internet access at home.

I replaced the hose and I found the vaccum hose for the tranny and hooked it up and tranny is shifting fine, but it is now overheating. I checked the coolant and the thermostat is opening and water pump is pumping (both top and bottom rad hoses are getting hot) If you have any suggestions, they would be greatly appreciated.

Thanks 410Fortune for the help earlier, I greatly appreciate it.

 

[410Fortune]

I would check the thermostat again, also make sure its installed the correct direction.
Always replace the thermostat when you have it apart, I also like to use a 180 instead of 195 and I boil the tstat in water at home to make sure it actually fully opens at 180.

It is also common to trap air in the system when re-filling. One trick to avoiding this is to pour very hot water down the upper rad hose into the intake manifold, the hot water will open the T stat and flow past it, getting rid of any air bubbles.


Was it overheating before you did all this work?

 

[sneeedle]

The car was overheating to begin with, that is what caused the heads to crack. I was just thinking about something that could be causing it, but im not 100% sure (fords arent really my thing, im more a honda/jeep fan) but when he runs his a/c the entire car smells like antifreeze, and he just told me on the phone than when he runs the heater, steam comes out, and he knows that his heater core leaks. Would that cause the car to overheat? Another reason im thinking heater core is because he said that the hose running from the IM to the firewall is what exploded this morning.

Also the thermostat is installed in the correct direction, and opening and the water pump is pumping. Because after we got it started last night, we ran the radiator with it open, and it was sucking water through.

 

[Diff Whack Daddy]

I would start looking at the radiator. I replaced an entire engine due to a cracked head and still had the same overheating problem with the new motor. I had the radiator rodded out and the problem was solved.

 

[Glacier991]

and on the 91 a heater core is a 15 minute job...(believe it or not). I'd have him replace it while he is at it. (1st Gen's were the glory days for FORD engineers and heater cores... in later versions it can be a half day job.)

 

[bslagle]

could a heater core leak cause it to overheat (it blows steam through the air vents but does not leak the liquid antifreeze)

 

[410Fortune]

not likely.
The heater core went south due to the real problem.
I would check the nylon fan for cracks, ensure the fan clutch still works and look into a new or rebuilt radiator.
this is after you are sure the waterpump is working.


Also stay far far away from cheapo heatercores, Checker, Autozone, etc...
I finally wised up after replacing 5 lifetime warranty el cheapos and got me a car quest unit

 

[bslagle]

The reason Im thinking that the over heating problem could be the heater core is the leak in the heater core is causing the cooling system to loose pressure (due to the steam leaking) but im going to change that out and see if it makes a difference. If that does not help then I'm going to get a high pressure flush to see if maybe there is something cloging the cooling system. I got the truck a few months back and I'm not sure if it has the original radiator, but it look newer, is there a way to tell? Also its not over heating too much (about the L in NORMAL) and it did not overheat before the heater hose blew yesterday (was running about the N in NORMAL). Thanks so much for your advice, it nice to see people help other in this day and age.

 

[bslagle]

Also after I replaced the hose yeaterday I added only anitfreeze, and I live in florida, could too much antifreeze and not enough water cause overheating?

 

[410Fortune]

no, and too much antifreeze will kill the radiator and heater core.
you must get the mix right, believe it or not too much antifreeze can also cause electrical problems.....

 

[Glacier991]

HIGHLY unlikely the heater core is related to the overheating issue in any mneaningful way. I'm with the notion that your raqdiator is the problem most likely (assuming the fan is operating properly.) Still, I'd replace that heater core. Not good to be inhaling atomized antifreeze.

 

[410Fortune]

deposits in the radiator = overheating
deposits in radiator = contamination in cooling system = heater core failure

I am not saying heat killed the heatercore, I am saying the same thing clogging the passages in the radiator kills heater cores.

 

[Glacier991]

Sorry 410... I should have said it differently. I should have said: "It is highly doubtful that the heater core played any meaningful role in the creation of the overheating problem." That is what I meant. Didn't mean to offend, and you have a valid point.

 

[Diff Whack Daddy]

If you have steam coming out of your vents, then the heater core is deffinately bad. The liquid residue from a heater core is caught in a pan under the heater core and drained through the firewall onto the ground in about the same lolcation as the famous A/C condesation puddle that my wife tells me about everytime.

 

[elkhunter]

If you still have doubts pull both heater hoses and hook them together with a metal or plastic connecter and run it. You could even leave it like that until you get the core replaced.

 

[bslagle]

Ok, I got the truck running and shifting right, now I'm having the overheating problem. I talked to a mechanic friend of mine and he said on the 4.0 there are 2 t-stats (but im questioning that) he said one is the top one on the upper rad-hose, then he said there is one at the bottom where the lower rad-hose connects to the block. Is this true, because I let the engine get up to normal operating temp and the upper rad-hose is hot and the bottom is cool, when I replaced the heads I took out the radiator and cleaned it out very throughly. Could the new t-stat be bad?? It worked for like a day and now I dont think its opening.

Also.....yet another problem, when I moved the truck the other day. I put it in drive and let it idle to my driveway, then when I have it gas to get it up the driveway it stalled, again and again. When I rev it up its fine, and to get it up the driveway I had to hold the gas and brake and slowly let off the brake....any suggestions?

 

[410Fortune]

Sounds like you have a problem with the engine?? or converter, hard to tell from what you describe.

The 4.0L has a single thermostat.
I have seen them fail
How long does it take before it begins to overheat? catalytic converter could be clogged

CEL come on?
How does the fuel pump sound? exhaust?

Glacier, hahaha man I didnt take it that way at all