Bingo! And to elaborate further, the fans come with their own shrouds as part of their assembly. The foam is cut from what the builders around here put between the base plate and the foundation when they build a new house. I've used weather stripping with a sticky side for the same application, but this and double sided tape is what I had handy.

 

I like the overflow bottle and hold downs...

 

Form FOLLOWS function.

 

Ok guys, contemplating electrics on the following-1987 26ft long class A motor home on ford's E350 stripped chassis; carb'd 460BB(stock exhaust manifolds, looking at headers in the future), C6 trans; 11,500lb GVWR. Probably has the biggest radiator ford made that year. Overheated constantly on the trip out to southern nevada this past june. Only has 60k on it; doesn't like to go over 60-65; no tach so I don't know what its spinning at that speed. Everything still stock, original so far. Have added several bottles of that stuff that helps to drop the coolant temps down. Ideas or suggestions would be nice.

 

"Overheats constantly" suggests the radiator is plugged up... which would not be surprising after 30 years. Get it serviced (ie. roded out by a good shop) or replace it would be my suggestion. Most likely the OE fan is perfectly OK.

 

And get a tach. Have a 75 gm chassis motor home. 55mph and she is happy and gets ~ 8 mpg. 65mph is all she will do with ~ 4 mpg. 31's and a 4.56 diff? Well that makes sense.

 

So just now with a new 13 lb thermostat, the engine warm, and the upper hose hard and obviously under pressure, I had an assistant bring the revs up to 2500rpm and noticed the lower hose collapsing a little. Had him blip the throttle with the same results. I then got in the cab and blipped it perhaps a little more aggressively. The hosed collapsed completely. I checked the upper hose and found that the radiator was no longer under pressure. Does anybody know why?

 

Possibly sucked air in due to the hose collapsing?


Get a spring in there ASAP - a coiled coathanger would so in a pinch but a new hose should have one in there already.


- boingk

 

Hi mate, welcome aboard.


First up, replace the thermostat. Sometimes they just go bad - this often means it will only partially open, or won't open until it is quite hot. Its a quick job that isn't expensive and will solve a lot of hassle if that's the problem!


My second stop would be to properly flush the radiator. Let it idle for 2 minutes to circulate the coolant and then drop the lot via the bottom hose - this will drain the block and radiator quickly. Have a big pail ready.


Reconnect the hose and refill with tap water. Run again for a minute or two until just warm at the radiator hose, then drain again.


Repeat this once more, but let the water circulate with a bottle of 'radiator flush' compound. The directions usually say something like 'run for 10 minutes or until at operating temp, then let sit for another 5 minutes before draining' - follow what it says and then flush once more with water before refilling with coolant. A lot of effort but will do a proper job of flushing the system.


Go for a cruise with your newly installed thermostat and flushed cooling system and see if the problem happens again.


For reference, if you have 4:56 gears and 31" tyres you're doing about 3200rpm at 65mph - the 460 will float the valves around 4500 ~ 4700rpm.


- boingk

 

Update: I have found that my nice great condition 3 core mountain of a radiator is/was mostly plugged. Makes perfect sense. The pump can't get recharge water fast enough through a plugged rad. Plugged with itty bitty pieces of RTV black. I obviously used improper technique putting the engine together last winter. (hangs head in shame).

I did make a coil out of stainless wire for my pump intake. Works good. An Oster pipe threading motor has many uses if you use your imagination.