FMX Cooling line replacement

The 69 needs new lines from the radiator. P.O. has the radiator rodded back in 1999 (i have the reciept), and “they” cut the lines and repaired them with lengths of rubber hose. They leak now. I have new SS lines coming and would like to know from y’all of any gotcha’s and tips. Also am i gonna loose all my precious Type F tranny fluid while they’re off etc.


Mike M.

Having caps ready to block off the radiator side as you disconnect will limit the amount lost. It runs slower than antifreeze and doesn’t really come out too fast. On the transmission side, it might need a plug instead of a cap to block it off. Have those ready and fluid loss should be less than a cup depending on the skill of getting the cap/plug to thread in place. If caps and plugs are not available, route a hose like a u-turn back to itself.

Jacking the back of the car may leak less on the trans side of the lines.

A large, clean catch pan is helpfull. I have reused transmission fluids by just filtering it through a coffee filter. 2 or 3 thick if you prefer. It can take overnight to filter it depending on the amount. It can be a good time to drain as much out and check condition of the fluid and pull the trans pan and check the transmission filter.

Blocking of both ends then gives time to remove and install new lines. Before any “capping off”, maybe get the new lines held up next to the ports just to make sure it appears things will line up.

Trans fluid and rubber hose is not an ideal combination. It tends to impregnate the rubber and cause the problem of leaking. If more time is needed beforehand, a new section of rubber hose and good quality worm clamps will most likely seal it up for a while. Make sure the hard line is clean and dry.

Type-F is getting VERY expensive too but, it is the recommended fluid. Wear rubber gloves.

Thank you, excellent reccomendations. I just happen to have a filter and gasket set on the shelf. I was always afraid of doing that maintenance because of the fluid loss. Now I can have a controlled drain to a clean container and filter the fluid for reuse. The coffee filters will have a tale to tell also.

Mike M.

When replacing the numerous pan bolts it is important to use a criss-cross pattern. Finger tighten all of them. Over tightening is very easy to do. INCH pounds. I do not use a ratchet. Screwdriver type force is really all the torque nessassery. Being equal is most important. As my hand goes round and round the pattern it becomes tired preventing me from over torqued. Just like head bolts, make several stages of pressure to final spec. Clean threads, and both surfaces to dinner plate status.

What is the torque spec for the bolts? I have a inch pound torque wrench.

Oh yeah i’m picking on you instead of googling it, just to get it all in one thread :stuck_out_tongue_winking_eye:


Mike M.

Oil pan to case = 12-16 Foot lbs says the manual.

10 lbs = 120 inch lbs

Personally I’m probably in the 70-90 inch range.

It would maybe depend on gasket type. Cork Vs other.
Meaning a spongy gasket like cork needs less. IMO

Using lock tight thread glue puts my mind at ease because of the low torque pressure.

Ooohhh, I have some Locktite gasket maker leftover from my racing days… off to the races…

And thank you very much.

Mike M

Good call on getting it all in the thread. I didn’t give it a second thought. I’m glad to be a part of this community and understand spreading experiences is the key here.

SS lines are not easy to work with. I try to use NICOP for everything

Alas, they are already shipped, now for the long afternoon on a cold garage floor🥶

I was going to mention a large piece of corrugated cardboard and a pillow…

The steel lines I ordered from WCCC were too long. I opted to cut them to the proper length and double flare the ends. Worked great and looks much better than the multiple s bends I have seen in photos. Not sure if that is an option with stainless if they turn out too long. I am guessing bending stainless is a chore.

I found that the top forward most port on the FMX was the big leaker. Not a lot from the radiator ports and the other port at the rear of the FMX.

Card board and a pillow…:rofl::rofl::rofl::rofl::rofl::rofl:

Hey man, thats half my life…
One time in '82 , when living in Wisconsin, I dug out the snow from under my '68 to fix a power steering leak. It was like an igloo with a chassis roof, cozy!
Oh, and a woolley hat!

Next part of getting all in one thread.


Mike M.

Just did this job last summer with a radiator replacement. Access to the rearmost fitting was rough with the exhaust in place. My exhaust is original and I didn’t want to deal with crusty bolts so I dropped the crossmember and lowered the trans a little bit to get access. Had to use a cut down flare wrench and a combination of wrenches/sockets because it had very little clearance to turn.
I would have also preferred NiCopp for the lines because it seals so much easier, the SS you have to really crank down on. I also got new fittings at the radiator end and a replacement used check valve for the rear trans fitting.

What ended up working to seal the best was some Parker Hannifin flare nut washers. They are copper crush washers for the flare fittings since the SS is so hard and the fittings are also steel. I normally would not do something like a washer in a flare fitting, but they are designed by Parker for this purpose and trans cooler lines don’t see particularly high pressures like a brake system would.

Parker 2GF-5-pk10

Thank you. I’ve been a bit wary of that rear connection on the tranny. Ive got stock dual exhaust, those pipes are in the way of everything.

M ike M.