FlyinMatt75
Member
Hey guys, first post and new owner of a 99 5.4L Expy with 230k. Need some help with some heater issues. Background, previous owner bypassed both front and rear heater cores years ago due to a leak on the rear core. They hooked the inlet and outlet from the block together as a quick fix. Well I'm gonna need heat this winter so it's time to fix this.
I verified flow through the front core in both directions and have a new rear core ready to install. I'm ordering the fittings to make my own hoses (quick connects, tees, spring clamps, hose, etc). So a couple of questions.
1. What is the flow direction from the block? Which tube is the inlet and which is the outlet. Can't find any info on this. Found the 1st pic below on the forum but my intake manifold does not have the vertical pipe on the front left side. Second pic shows my situation with the current bypass. One pipe comes up and make a 90 towards the passenger side and the other is laid over at 45 degrees up against the fire wall. This is the source of my confusion.
2. Does flow direction through the cores matter? If so, what is the connection pattern? Pics of your lines would be helpful.
3. Since I have good flow through the front core and will be putting in a new rear core, would it be best to do a flush before I hook up heater core to the system?
4. My coolant in the overflow tank looks like muddy water. Think I might need a coolant filter? Recommendations?
Appreciate any help, especially pics!
Thanks!!
I verified flow through the front core in both directions and have a new rear core ready to install. I'm ordering the fittings to make my own hoses (quick connects, tees, spring clamps, hose, etc). So a couple of questions.
1. What is the flow direction from the block? Which tube is the inlet and which is the outlet. Can't find any info on this. Found the 1st pic below on the forum but my intake manifold does not have the vertical pipe on the front left side. Second pic shows my situation with the current bypass. One pipe comes up and make a 90 towards the passenger side and the other is laid over at 45 degrees up against the fire wall. This is the source of my confusion.
2. Does flow direction through the cores matter? If so, what is the connection pattern? Pics of your lines would be helpful.
3. Since I have good flow through the front core and will be putting in a new rear core, would it be best to do a flush before I hook up heater core to the system?
4. My coolant in the overflow tank looks like muddy water. Think I might need a coolant filter? Recommendations?
Appreciate any help, especially pics!
Thanks!!
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