Coolant leak, engine valley, bypass tube?
#1
Coolant leak, engine valley, bypass tube?
I've got a 2000 F-150 4.2L that seems to have a pinhole leak in the coolant bypass tube (?) situated in the engine valley just behind the thermostat housing. This is a 6" L-shaped aluminum tube that connects to a 5/8" hose that runs down to the top of the water pump. How to repair? Is this tube pressed in? Threaded?
Any advice/help on this would be greatly appreciated.
Any advice/help on this would be greatly appreciated.
#2
#3
#4
Okay, so I'm feelin' pretty good tonight... I had the problem with the pinhole leak and today I seem to have dealt with that. Sorry to say I had to go to another forum for help, but found a guy who had patched the hole with no negative results for a year. So, today I rounded up a length of 5/8" heater hose and, with the help of some water-based lubricant (okay, okay, I'll tell you it was Astro-glide---borrowed it from my wife...) I was able (with no small amount of effort) to force it completely over the 6" long, 90-degree bend in the tube and right down to the engine block. I added three hose clamps and was able to effectively seal the pinhole leak in the tubing. Now, that being said, I've only run it for a few minutes, but there is no sign of a leak now. I'll drive the truck more this week and see if it holds, but I'm optimistic, given that another guy has driven his for a year with no problem, and his was even more of a hillbilly-rig than mine, since he actually split the tubing he was patching with and then clamped it into place, although he used some JB Weld first. For future reference, and, in deference to my Herculean effort to cure this problem, we'll call it the "Modified Hillbilly Rig". Patent law aside, feel free to use this method as the need arises... It'll save you about $850 (for the dealer to remove the old pressed in fitting and replace it with a new one, after removing the intake manifold), so it's certainly worth a try...!
#5
Hate to admit it but used the same type of repair on mine. My bypass blew a pinhole after replacing the radiator. After doing some checking on the tube and cost of replacement, cut out the bad section, slid the heater hose on and triple clamped both ends.
It has now been about 6 months with no leaks. With nearly 300k now on the 4.6 '97' it is tough to justify the cost of replacing the bypass.
It has now been about 6 months with no leaks. With nearly 300k now on the 4.6 '97' it is tough to justify the cost of replacing the bypass.
#6
Charliebravo was the removal of your 4.6 intake a hard job?I have a pinhole leak thats hitting the back of the firewall just to the right of the 5/8 heatercore tube fitting.Is this the same leak you all are talking about?I was looking in my haynes manual and it appears that the there is a 1/4 hose and fitting running horizontally behind the intake.
#7
Charliebravo was the removal of your 4.6 intake a hard job?I have a pinhole leak thats hitting the back of the firewall just to the right of the 5/8 heatercore tube fitting.Is this the same leak you all are talking about?I was looking in my haynes manual and it appears that the there is a 1/4 hose and fitting running horizontally behind the intake.
The bypass tube runs from the back of the water pump housing to the rear of the block through the valley. At the back it turns left and up as looking from the front.
The overall job of removing intake, replacing plugs and knock sensor took about 4-5 hrs as I recall.
Good luck!
Trending Topics
#8
My leak seems to be a pin hole leak that shoots against the firewall slightly lower to the right of where lower heatercore hose attaches to metal tube.I think the tube has the hole near where it attaches to block. I have the Haynes manual and will see where that knock sensor is located.Is that a dealer only item?Is that 5/8 tube the only size running back there?
#9
My leak seems to be a pin hole leak that shoots against the firewall slightly lower to the right of where lower heatercore hose attaches to metal tube.I think the tube has the hole near where it attaches to block. I have the Haynes manual and will see where that knock sensor is located.Is that a dealer only item?Is that 5/8 tube the only size running back there?
#11
#12
#13
Did not even try to get my hands in there. The valley was full of coolant. Thinks the worst, was ready for the worst. Had all the gaskets, tools, plugs etc before starting the project.
#14