Motorcraft Radiator hoses, no spring included

Over the weekend I finished up the timing job on my '69 351w including new radiator hoses. When I ordered all my parts I found that Rockauto had Motorcraft hoses in stock (still not sure if I’m going to go with the larger radiator upgrade in the future so I didn’t spring for the concours hoses). The timing job went as well as can be expected on an installed engine that hasn’t been opened since the factory, but at the very end of the project as I put the hoses on I noticed the new lower hose didn’t have the spring in it, and foolishly I figured this must have been a purposeful deision from motorcraft for a stronger new hose or something. The old spring was much too crusty to be salvageable so I put it all together, bled the system and took it to a local show.

On the way to the show it ran fine, but afterwards on the way to a friend’s shop to hang out it started running warm on the highway, and burping steam/coolant once I parked, it was a short drive and even while it was burping steam at the curb the temp gauge only made it to 3/4. So I think I will be safe. Ordered a spring from NPD and I’ll change the oil to be sure nothing got milkshaked. Incidentally with the shipping from NPD it would have been cheaper to buy the concours hoses in the first place.

The spring in the lower hose was needed on the assembly line to keep the hose from collapsing from the suction fill method employed there. It’s a common trailer park myth that it’s needed later - it won’t actually affect anything.

It’s common for 50 + year old radiators to be no good, the sediment inside the tubes keeps them from conducting heat well. Another very common thing is that someone has changed the temp sender and now the temperature reads higher than it actually is because the “new” thermister is simply incorrect. More here:

The car did not have this issue beforehand, and the temp sender was changed to a motorcraft original sender previously that does read correctly.

Scale and corrosion in the radiator/block I’m sure is an issue that I will address in the near future as it has run warm sitting in traffic before, but that would also exacerbate any collapsed hose issues as well.

Also, I’ll be borrowing a friend’s vacuum filler for this fill to rule out any air pockets. And a new radiator cap to elminate one more question.

I would use an infra red thermometer to read the actual temperature at the temp sender. Also, if the radiator is overfilled it will spit out the unnecessary coolant when it’s warm. Aftermarket flex fans and lack of a fan shroud are additional causes of temp issues.

Agreed you dont need the spring rather just a quality hose. Ensure your coolant system is in working order and if you have not flushed it yet that would be advisable as well.

Before I replaced my radiator I flushed the system as I knew the coolant was not in the best of shape. I had flushed it with coolant and water previously to get the old stuff out but that was not enough to remove the scale and nasty inside the block and radiator that had built up from years of sitting. I was impressed with this flush chemical I had found on NPD. It removed everything from scale to rust and left the system clean, It did a good enough job on the radiator that I felt bad replacing it but it was getting swapped for the larger unit anyway.

All good tips, thanks guys. It has the stock 4 blade fixed fan and shroud at the moment. I’ll certainly give that flush a try, I’ve had good luck with Evaporust products in the past, though I’ll wait until I can take some time with it to address any leaks that crop up, as well as install the new set of heater hoses I got. I’ll use my buddy’s vacuum filler/bleeder to avoid any air pockets on this fill so I can get it out of his shop and back to mine.

I’ll also double check the timing, didn’t have a chance after doing the timing set and I suspect that is contributing to the heat. And then dig through some of these threads on a coolant expansion tank for something that looks factory, I don’t like relying on my eyeball calibration for the radiator fill level.

Originally there was no coolant expansion tank - that’s something that came much later Don’t over fill the radiator and you won’t have any issues that require one.

Got the spring installed in the lower hose and the new radiator cap, vacuum filled/bled the system. Still running warm after 8-10 miles (not freeway this time, ambient temps in the 80s) but no burping of steam or coolant. I’ll have to get some more accurate temp numbers when this heat wave is over. I’ll also go for the radiator flush, I confirmed that the cooling system held vacuum when I filled it so I should be fine on leaks.