93 Escort Bump/Heating Problem

My car is a 93 ford escort, automatic 1.9L, regular (Not LTS), 140,000miles. Here's it's main problem, it has a noticable and annoying bump when it shifts from 1st to 2nd. More specificaly it's a sort of sudden quick pull forward(as if someone gives you a sudden push from behind), almost as if the engine is moving on it's mounts. Furthermore the bump is more pronounced under normal acceleration, less with barely any acceleration, and less with very quick accelertion. The bump/thump is kind of smooth when the car isn't warmed up yet, but once it warms up, like when it reaches normal operating temperature, the bump becomes less pronounced from 1st to 2nd, and develops more of a pull backward(noticable hesitation) or a bump backwards from 2nd to 3rd. Also I notice that when the car is moving uphill, when starting out for example on an uphill stop light the bump is not noticable from 1st to 2nd, but again the pull backward from 2nd to 3rd. I've read through several web sites on what could be making this bump. It's been there ever since I bought the car and has become more pronounced after I replaced the cylinder head due to it leaking antifreeze. I was wondering if this could be due to bad mounts (changed all including the transmission one, except the back of the engine one which seems in good condition), or maybe, as some others have suggested, due to bad lubrication of the driveshaft, or something to do with the driveshaft or half shafts. I've also changed the transmission fluid and filter, and that only fixed the tcc shudder problem the car had, but the bump is still there. There aren't any leaks.

The second problem with the car is not as annoying but could potentially mess up my engine again. First of all the thermostat, water pump, and heater core have all been changed and including the radiator fan, are all in excellent working condition. The temperature stays mostly near the middle, as indicated by the temp guage, but varies depending on the conditions outside and especially when the fan isn't on. Sometimes it goes near the hot mark all the way to the top and not until the fan turns on does it go back near the middle. I was wondering whether this variation in temperature could be harmful to the engine and whether something could be causing it, like a bad radiator, as that is the only thing I see left that hasn't been replaced, and has a lot of debris in between the finns. I was wondering if maybe the radiator could be the problem as it could probably not be dissipating the heat correctly due to the debris present.

Anyone with previous experiance or any suggestion to a possible resolution to this problems would be greatly appreciated.

Answered both my questions. Posting this for someone with a similar problem that has been wondering whats wrong. The shifting problem and the pronounced bump was due to not adjusting the throttle valve linkage cable pressure after replacing the cylinder head. This is critical for correct shift timing on the 91-96 Escorts/Tracers and possibly others. The procedure is to get a wrench and locate the throttle cables on top of the intake manifold. There should be two bolts on the lower cable. Start the car, let it idle and reach normal operating temperature. Then loosen bolt 1 and then bolt 2. Bolt 1 must be loosened first before loosening bolt 2. Bolt 1 is on the right and bold 2 is on the left right next to it and they should have the numbers on top of them. After loosening both bolts, tighten bolt 1 and then adjust the cable by pulling it to the left or pushing it to the right. Pressure increases to the left and decreased to the right. If there is too much pressure the car will shift with a pronounced bump, if there is too little pressure it will shift too soft and possibly with nuetral in between. Normally this requires a transmission pressure guage which should read 71-74psi, but this procedure can be done by guessing and then testing until you get the right feel in the shifting, then the pressure would most likely be correct. I've done this all by guessing, but I tested the pressure anyway and it was withing specification. After adjusting the cable in either direction, make sure you tighted bolt 2 so that the cable cannot move anymore and go test how it shifts. Afterwords repeat the procedure, increasing or decreasing the pressure by moving the cable to the left or right, if shifting doesn't feel right. Of course, this is for the automatic transmission.

To my other problem the solution was a new radiator, which now keeps the temperature constant with guage reading always at the middle.

I hope this helps someone, it sure had me for long time as no one says anything about this in all the places that I've been, and it's only listed in a very small section in my manual that's not even related to the problem I was experiancing, but it sure makes a world of difference.

my escort has been doing the thump shift thing in first to second gear and i would just let off the accelerator a tad to make it slip into gear smoothly. But i did what you suggested with the cables and it really works. it's alot smoother, thanks for the advice, I did a whole bunch of stuff to try to correct it and this worked the best. :)