re-intro and THANKS! (and maybe a few questions)

swinks1966 · July 20, 2005, 05:40:31 PM

hi all,

first I want to say Thank you all. Thanks for what you ask? Inspiration, Motivation, sharing your knowledge, and keeping me busy reading about hot rods! I think this is one of the best hot rod sites out there. IF it wasn't for this site, I know for sure my truck would not be at this stage of completion.

What truck you ask? I attached a pic. IT is a 1966 Ford f100, now a hot rod. What you see to this point has been entirely done by me. I have owned this truck for about 7 or 8 years. I put a mustang 2 suspension up front, and put the rear end on top of the springs out back (i think i want to lower the back a smidge, maybe an inch.) I am running a 351W that was built by me with aftermarket heads, and the normal warm up stuff.

lately(the past 3 weeks), I have been bustin' butt on it (10+ hour days on it) and now it is supposed to be in driving mode. At first i had it set up with an AOD, but i ruined that transmission because the lines were leaking ALOT and i think it both ran out of fluid, and the line pressure was not adequate. Now, yesterday i pulled it and put in a C6 in. I have it all set up properly I think, but i still have problems. I have driven it down the road, and when it is still warming up, it shifts fine. 1-2-3. once it gets hot, it bogs down, and absolutely does not go right. I think it might be slipping pretty good too. Do I need a trans cooler besides the one in the radiator? probably should add one anyway. The fluid is new and doesn't really smell or look burned yet. I have only gone a few miles. when it does this on the road, it starts going real slow, no matter what gear you put it in.

After sitting for a few mins, it runs good in park, but then once you go into a gear, it begins doing the bog down thing, even in neutral. and in park when you go back to it.

These transmissions are both used. the history was not known on the C6, and the AOD worked until I smoked it.

I also think i have a problem with the front brake system. It seems like the fluid is getting too hot in the lines, causing the brakes to activate. when i crack the bleeders, the fluid is pretty warm if not hot. I thought that I had the lines far enough away from the exhaust, and I relocated the one that crosses over to the passenger side, and it seems to help, but after a longer time now, it still gets hot. the line is at least 4" away from the header on the passenger side, and more than that on the driver side.

This kinda stuff is just breaking my heart. This is my first real hot rod build.

Joe

formerly fordiac, thats what the reintro is about.

enjenjo · July 20, 2005, 08:39:29 PM

I think both your problems are related. I believe your front brakes are dragging, causing the fluid to heat up, and making it act like the trans is bad. When you let it set, the brake fluid bleeds out, releasing the brakes, and it starts all over again.

Make sure your pedal, or booster is not holding the brakes partly applied.

swinks1966 · July 20, 2005, 09:13:04 PM

I must have forgotten to mention, the engine/trans does it even when parked(at a dead stop, not moving). but only when it is warmed up/hot.

I have the vaccuum modulator hooked up to manifold vaccuum coming off the edelbrock carb. should I move it to the intake instead?

when the truck is totally cold, the brakes do not act up, and act like a normal car when I place the trans in neutral. it rolls easily. once it gets hot, the brakes are locking up.

thanks.

Joe

enjenjo · July 20, 2005, 09:27:37 PM

What are you using for a master cylinder? Booster?

swinks1966 · July 20, 2005, 10:35:35 PM

Quote from: "enjenjo"What are you using for a master cylinder? Booster?

The booster is from a ford pickup, rebuilt, and I am using some original ford pickup brackets to mount it to the firewall. So, i wouldnt think that it is screwing up there. the master is from a 68 thunderbird. it is from a bower brake setup. I am also using the brake control valve from the same t-bird.

The brakes feel great when it is cool. and when the engine is started, the power portion works, I can feel the pedal drop.

The only way to fix a line overheating problem is to move them right?

I can try to take pictures of my brakeline routing tomorrow.

Thanks,

Joe

enjenjo · July 20, 2005, 11:37:07 PM

If the fluid coming out of the calipers is hot, the problem is not the lines passing close to the exhaust several feet away, it's the brakes dragging, and heating the fluid at the caliper. If the line is 4" from the exhaust, that should be more than enough room.

You will have to check the pushrod length on the booster, to see that it will let the master cylinder retract completely to release all the fluid. Otherwise the small amount of pressure left in the lines will make the brakes drag.

Ford used two different sources for boosters and master cylinders, and they used two different push rod lengths. In addition, the pushrod is adjustable, and in many cases is adjusted wrong. It is certainly worth checking.

swinks1966 · July 20, 2005, 11:53:04 PM

Thanks for the explination. I was figuring the fluid was hot because the exhaust. When I put my hand where the line passed, the frame was hot to the touch (boxed frame, Mustang suspension) I will look at this tomorrow

Youre talking about the pushrod between the booster and the cylinder? the rod coming out of my booster to the pedal isnt adjustable I dont think.

It might be easy to check the dragging problem, crack the bleeder, push it around, then hit the brakes a few times, then try pushing again.

Any ideas on the trans/engine problem?

The fluid level is correct as far as I know. checked in park while hot, with the correct dipstick.

swinks1966 · July 21, 2005, 01:04:56 PM

I adjusted the pushrod, i think that might have helped, but havent done a road test yet.

I am workin on adding a trans cooler. Have all the brackets made up, waiting for paint to dry, then will have a road test.

Enjenjo, what do you like for "universal" electric brake switches? the pressure switch i put in is not working. I think i would rather hook an electric one up. I have plenty of room to put one under the dash on the brake pedal. I wonder if a ford truck one would bolt right on?

I also need to get a neutral safety switch for the c6 I put in. Does anyone know a NAPA or car quest part number for a trans mounted switch? the trans I have right now doesnt have one on it, can the trans mounted NSS be put on any c6, even if it doesn't have one originally?

thanks.

Joe

enjenjo · July 21, 2005, 02:40:46 PM

If you are using a stock pedal, the Ford truck switch should work ok. If the bosses are cast in the case to fasten it down, the trans mounted NSS should fit.

Bruce Dorsi · July 23, 2005, 10:19:05 PM

Joe, thinking about your problem from a different perspective, your brake dragging problem could not be caused by heat if all the components are operating/adjusted properly.

When you release the brake pedal, pressure in the lines is relieved by allowing fluid to flow back to the master cylinder. ....The pressure will drop to zero, or to the rating of the residual pressure valve, if so equipped. ....Any expansion of the fluid due to heat will flow back to the master cylinder without causing the brakes to activate.

If the piston of the master cylinder does not return fully, a port in the master cylinder will be blocked, causing the pressure in the lines to build. .... If the booster rod is too long, preventing the piston's full return, the brakes will drag as Enjenjo has pointed out.

Another possibility is that the master cylinder you are using is for a drum brake circuit, and is equipped with an internal residual pressure valve rated for use with drum brakes. .....Did the '68 T-Bird have drums or discs for front brakes? (Yes, is not the answer we're looking for.

)

RPV's for drum brakes maintain a higher residual pressure in the brake lines than a rpv for a disc brake circuit. This higher residual pressure WILL cause the calipers to activate and cause brake drag. .....If you are using disc brakes on the rear, the wrong residual pressure valve will make the rear brakes drag also.

Bruce Dorsi · July 23, 2005, 10:35:18 PM

Quote from: "Bruce Dorsi"Did the '68 T-Bird have drums or discs for front brakes? (Yes, is not the answer we're looking for. )

- - - - - - - - - - - - - - - -

Upon looking in a Wagner brake catalog, I learned that all T-Birds from 1965 to 1980 had front disc brakes.

If your master cylinder is indeed the correct one for a 1968 T-Bird, my suspicion of an incorrect rpv is not valid.
.....BUT, are your front brakes connected to the correct port of the master cylinder? .....Since the T-Bird had rear drum brakes, that m/c probably had a rpv installed in one port.

purplepickup · July 23, 2005, 11:13:20 PM

Quote from: "Bruce Dorsi"[If your master cylinder is indeed the correct one for a 1968 T-Bird, my suspicion of an incorrect rpv is not valid.

Valid for swinks or not, your post was some good info. I wish I had your memory for details.

swinks1966 · July 24, 2005, 12:31:44 PM

i think i have all these problems sorted out. The engine was running real hot, and i am pretty sure that was the cause of some of my problems. I added an electric fan and an additional transmission cooler.

Like enjenjo suggested, for the brakes,I adjusted the pushrod, and it is good to go.

I actually took it up to a local cruise in they have every saturday. had a great time, parked next to some stock 66 f-100 trucks and got to see how much lower mine was. very exciting. had a good talk with a guy there who had a 63 f100.

I want to thank you all for your input.

Joe