How do you replace a coolant bypass line that is leaking above the thermostat on a Ford Windstar?

Answer 1

Just had this issue on my 1999 Ford Windstar (3.8L). In my instance it turned out to be a pinhole in the crossover coolant tube that rises up out of the lower intake manifold on the driver-side of the engine (above the thermostat housing and below the MAF) and shoots off at a 90 degree angle across to the passenger side.

This tube is nearly impossible to see until you remove the upper/lower air intake (large black clamshell looking thing) from the lower manifold. Trust me - it is there.

Project details:

You will need to remove the: Neg. battery cable, various electrical and vacuum connections, the windshield wipers and cowl assembly, air cleaner assembly, throttle cables, upper/lower air intake, and of course the tube itself.

While it sounds like it is a pretty difficult project , it was not too bad really.

Just get a Haynes manual for your Windstar (about $20 at most auto parts stores) and read up on how to remove the upper/lower air intake.

It really mentions nothing about the tube in particular though. It is all relatively light work. The largest tool I used was the 15mm wrench to remove the windshield wipers :-)

Tools/Parts:

A set of small 1/4" deepwell sockets, and ratchet made the work go quickly. You will also need a straight screwdriver and some pliers for loosening/removing various hose clamps. I just used a med. sized adjustable wrench for the wipers.

The gaskets on the upper/lower air intake were reusable, and the tube I had welded up by a friend (it is about $55-$75 at the dealer if you have no welding friends).

If you repair your old tube, be sure to replace the o-ring on it while you are in there. My dealer actually *gave* me a new one, so my total cost for the project was a few hours of my time and $0.00 for parts (already had the manual).

AnswerOn my 2002 Windstar, first you disconnect the 2 clamped hoses, then unbolt the 2 bolts,(one on the water pump and one hidden further down behind coolant tubes)finally you pry up the bypass tube with flathead gently from the water pump. may take a while to work it out once loose.

Where to buy: Your local Ford dealership parts department

Bypass HoseHaving just changed mine yesterday, I can tell you that I removed the fan shroud, top hose from the radiator, fan from the water pump (this takes a large adjustable wrench as the fan clutch is threaded onto the end of the water pump shaft), serpentine belt, and idler pulley. I then disconnected the battery cables, ac compressor from it's mounting bracket (unplug the electrical connector but don't remove the ac hoses, just pull the unit out of the way), heater hose from the right side of the water pump, and alternator/ac mounting bracket from the engine (pull this out of the way also). You can then change the bypass hose on top of the water pump. Be sure not to pinch the wires going the ignition coil (if mounted to the front of the passenger side cylinder head) as I did this and caused a short unknowingly. All this trouble for a $1.99 hose. :) Answer

As a temporary fix try taking a bigger piece of hose, slitting it in half and placing it over the hole. Next take a hose clamp and place it over the part with the hole and the rubber hose and tighten it down. It might take two or three hose clamps. This wont be perfect, but will allow you to drive it until you get replacement piece or feel like messing with it. Hope this helps.

I don't know what it is called but I had to replace one due to a pin hole worn in the bend.

Not too complex, don't need to remove the pump, need long skinny arms and large hands, otherwise is slow going. Recommend hose clamp pliers. I pulled off the front hose at the water pump first, then the one to the recovery tank, un-boltedat water pump and Power Steering pump, popped it out of the water pump(pry with large screw driver under flange with right hand and tug tube with left hand), rearranged the hoses temporarily for easier access to the last clamp. There was a tube mounted on a bracket on the PS pump that I had to pop off to remove the ty tube once disconnected. Installation is easier than the removal. Hope this helps.