OK so I have spent most of the afternoon going over all the ways to flush the coolant system on my 80.. After getting the cruiser up and running my son and I took it out on its first Highway drive in a few years. We inherited this cruiser from a friend that had a mechanic try unsuccessfully to replace the HG. And it never ran after he got it back so it sat for a few years outside and he gave it to us to see if we could get it running. Well the mechanic appeared to have actually gotten the HG on properly but did not install the cams correctly. We fixed the cams got it running and tested the HG with one of those green\blue chemical testers.. However when coming back into town it started to over heat. We pulled over and let it cool down and limped home. After cooling off for a few hrs I opened the rad cap and noticed what looked like a big gob of paper pulp.. Thinking this may be old HG material and sludge? Anyhow sounds like a full flush is in order for us.. How do you guys do your flushes? I may be totally over thinking this as I tend to o but here is what I have come up with.
Drain coolant:
Drained the rad through the petcock.
Also drained through the block drain.
Back flush heater cores:
1. Disconnect pass. Side heater core hose this is your outlet hose.
2. Connect garden hose water supply to this disconnected hose.
3. Disconnect U bend hard line from both hoses on the heater control valve
4. Connect clear tubing to the lower hose number with a 5/8th barb fitting. The other end goes to a bucket.
5. Turn on the water supply about half way not too much pressure. Let all the gunk flush out into your bucket.
6. When you have clear water flowing through blow remaining tap water out with air compressor.
Back Flush Radiator:
1. Remove Thermostat and Connect 1 inch OD PVC pipe with garden hose adapter\reducer to the vertical hose right before going into the thermostat housing and secure with hose clamp.
2. Connect Prestone yellow neck thingy to the radiator cap. Connect the other end to a hose going to a bucket.
3. Turn on the water and back flush the radiator until fluid from the outlet hose connected to the radiator filler hole is clear.
4. Drain radiator of all water from petcock
Back Flush Block:
1. Connect water supply hose to Heater core inlet hose this is the upper hose that is connected with the hard U shaped line on the Heater control valve. Be sure heater is on Hi and Ignition is on to open valve.
2. Remove engine block plug
3. Turn on water and flush system until clean water comes out of the engine block.
4. Repeat radiator back flush steps to flush more out.
Refill system with new Coolant 50/50 distilled water.
Am I over thinking this any other suggestions before I start? Any others have a easier way to do this? I could also just back flush everything through the Heater core outlet with the Prestone kit.. But I am afraid of flushing a bunch of stuff through the block and what not.. Again I may be over thinking it..
Thanks
Drain coolant:
Drained the rad through the petcock.
Also drained through the block drain.
Back flush heater cores:
1. Disconnect pass. Side heater core hose this is your outlet hose.
2. Connect garden hose water supply to this disconnected hose.
3. Disconnect U bend hard line from both hoses on the heater control valve
4. Connect clear tubing to the lower hose number with a 5/8th barb fitting. The other end goes to a bucket.
5. Turn on the water supply about half way not too much pressure. Let all the gunk flush out into your bucket.
6. When you have clear water flowing through blow remaining tap water out with air compressor.
Back Flush Radiator:
1. Remove Thermostat and Connect 1 inch OD PVC pipe with garden hose adapter\reducer to the vertical hose right before going into the thermostat housing and secure with hose clamp.
2. Connect Prestone yellow neck thingy to the radiator cap. Connect the other end to a hose going to a bucket.
3. Turn on the water and back flush the radiator until fluid from the outlet hose connected to the radiator filler hole is clear.
4. Drain radiator of all water from petcock
Back Flush Block:
1. Connect water supply hose to Heater core inlet hose this is the upper hose that is connected with the hard U shaped line on the Heater control valve. Be sure heater is on Hi and Ignition is on to open valve.
2. Remove engine block plug
3. Turn on water and flush system until clean water comes out of the engine block.
4. Repeat radiator back flush steps to flush more out.
Refill system with new Coolant 50/50 distilled water.
Am I over thinking this any other suggestions before I start? Any others have a easier way to do this? I could also just back flush everything through the Heater core outlet with the Prestone kit.. But I am afraid of flushing a bunch of stuff through the block and what not.. Again I may be over thinking it..
Thanks
