How do I circulate coolant in my COE

348tripower · July 04, 2013, 06:19:24 AM

I just took the COE for a 75 MPH run for a half hour. When I stopped for gas this thing heat soaks to the point it is hot and hard to start. I am thinking if I can keep the coolant moving thru the radiator it would fix this. The plumbing is real long with the engine behind the cab. The cooling system seems to be efficient. The harder I run the warmer it gets. If I slow down it will cool back down. Any thoughts ?

348tripower · July 04, 2013, 06:32:39 AM

This is expensive but it should work.
EMP/Stewart Components E389A-BK34 - EMP Stewart Electric Water Pumps
What about some kind of a 12 volt timer to run this?

enjenjo · July 04, 2013, 10:02:33 AM

There are a ton of 12 volt pumps in the $100 range that would do the job. I would run it as a bypass to the main line in parallel with a check valve. There are 12v timers on ebay for reasonable prices.

Crosley.In.AZ · July 04, 2013, 01:24:31 PM

Don: hard to start? Cranks sloooow? Cranks a long time?

Would a stratgeticllly placed fan running help? Mayb a cheaper option to test first. Even a fan like offered for interiors? Small one.

just an idea..

Seems like Jeeps years ago... had a factory fan that blew on the engine ? At the EFI or dizzy or something. I remember the fans under the hoods on some Jeeps

phat rat · July 04, 2013, 01:31:13 PM

I know some will disagree but I have an electric fan with a rheostat on a always hot circuit. It used to boil over sometimes after shutting it off until I did this. Now it can cycle if it needs too.

wayne petty · July 05, 2013, 02:24:06 AM

Quote from: "348tripower"I just took the COE for a 75 MPH run for a half hour. When I stopped for gas this thing heat soaks to the point it is hot and hard to start. I am thinking if I can keep the coolant moving thru the radiator it would fix this. The plumbing is real long with the engine behind the cab. The cooling system seems to be efficient. The harder I run the warmer it gets. If I slow down it will cool back down. Any thoughts ?

did you see my theory on cooling system dynamics ..

http://www.roddingroundtable.com/forums/viewtopic.php?t=12926

got a thermostat??? 192F

got a bypass circuit???

got magnets inside the fuel tank to keep any sediment trapped??? out of the fuel filters.. out of the fuel pumps and needles and seats in the carbs..

can you measure the fuel pressure... after shut off??? does it stay up???

do you have a fuel injection type of fuel filter right before the fuel pump inlet??? so the check valves stay clean. holding not just the fuel pressure in the pump. but also the fuel pressure in the line to the carb...

dirt in the fuel system can have 2 effects on your troubles..

first.. if the fuel pump check valves are dirty.. it may not be able to keep up enough pressure to push fuel thru the needle and seat opening at high speed.. lowering the fuel bowl level and leaning out your engine at high speeds causing over heating..

what.. many years ago.. my former boss .. a PBY5 flight mechanic.. had a customer come in with a big motor home with an overheating issue.. it had always run fine before.. this just cropped up.. the radiator was changed.. thermostats changed.. water pumps changed.. it would only overheat going up the long grade going north out of los angeles on highway 5.. eventually he hooked a fuel pressure gauge into the line at the carb.. during the long upgrade fuel pressure dropped from 5 psi to 1/2 a psi..

a full flow cranking test was performed for 10 seconds as the manual showed.. flowed great for 9 seconds then started to drop off.. so we did it for 15 seconds.. and it dropped to a dribble.. digging thru the fuel lines.. we found that the camping world mechanics had installed a new generator set.. and used a MULTI SIZED Vacuum only TEE in the fuel line from the tanks .. they did not cut the tiny sizes off.. so there was the 1/16" restriction in the 3/8 line.. since it was all the way back of the motor home.. there was enough fuel in the lines for a 10 second cranking test.. where the 15 second test showed it right away.. since then i always recommend a 15 second full flow cranking test.. into a clean, clear plastic 2 or 3 liter soda bottle.. clear so you can check for sediment and clean so you can pour it back into the tank.. COLD ENGINE.. IGNITION COIL DISCONNECTED

before hooking the carb back up.. either use your thumb over the fuel line and crank it.. then stop cranking.. hold the fuel line for 15 seconds.. release.. does it still have fuel pressure??? or use a gauge on the end of the tube... there are female inverted flair to hose barb fittings at some parts stores..

loss of fuel pressure during high speed runs can also cause issues that are actually known a vapor lock.. where the fuel pressure in the line between the pump and the carb.. and in the main body of the pump is reduces.. this allows the fuel to boil at a lower temp and the vapors expanding prevent the fuel from being pulled up thru the inlet check valve..

i have one some vans.. actually installed a second windshield washer pump system.. that sprayed water directly on the mechanical fuel pump.. this cooled the fuel inside during hot restarts and while sitting in traffic.. preventing vapor lock...

i have not had to perform this since learning about magnets in the fuel tank and better fuel filters.. lately i have been using ford inline fuel filters for fuel injected cars and trucks. since they are easily hooked up with rubber fuel hose and clamps and almost every parts store and big box store has them in their automotive department..

and.. yes.. you can use some kind of electric fans or ducting blowing up from under the box to keep the engine cool..

that is a LOT of money for the inline electric water pump.. i would tackle the fuel issues and testing first...

do you have the heater core hooked up... mercedes have an inline 12 volt 5/8 hose heater hose booster pump on later 80s 190E and 300E models.. probably others also that type of pump might be better at removing the heat from the engine.. leaving the circulating pump and heater fan running.. depending on how it's all routed... or is the radiator in the back with the motor..

what are you using to drive the radiator fans up front?

is is all electric radiator fan motors.. and ram air at speed..

are there flaps around the radiator to keep the ram air thru the grill going thru the radiator. not going around it..

i have always looked at the toyota previa mini van accessory drives and wondered about using them in a mid or rear engine application to spin the mechanical fan .. power steering pump, ac compressor and alternator

in case you are not aware. they are a partial engine front.. driven via drive shaft on the front of the damper.

i am not trying to reengineer your truck.. only attempting to help from afar..

348tripower · July 05, 2013, 07:17:11 AM

got a bypass circuit???
Explain?

is is all electric radiator fan motors.. and ram air at speed..
Electric fan from a newer Lincoln

are there flaps around the radiator to keep the ram air thru the grill going thru the radiator. not going around it..
I have the original metal parts. I am ging to see if I can modify them or add rubber.

There are a ton of 12 volt pumps in the $100 range that would do the job. I would run it as a bypass to the main line in parallel with a check valve.
There are 12v timers on ebay for reasonable prices.

Maybe just a timer to run the fan for a few minutes. It will cool down but I am always afraid of running the battery down. I did a search on timers but I really didn't know what to pick. Seems they were more for industrial apps.

GPster · July 05, 2013, 09:57:49 AM

Is the engine box and the radiator area in the front of the cab connected by the area under the cab? If not then you have two boxes with their only outlets on the bottom. Hot air is going to trap itself at the top of those boxes. With-out the truck moving your radiator area is going to be just like trying to push air through the radiator with a fan. The radiator is going to have hot water at the bottom if it's got stagnant air and the water that you pump or pull back into the engine with an electric pump is going to take a long time cooling that engine down that is trapped in a stagnant area. Also any cooling circulation is going to stop as soon as the engine's thermostat closes and the thermostat in a EFI engine is bound to be fairly high. Maybe if the radiator and engine compartments were connected with some kind of belly-pan and you had a temperature controlled fan on the top or back of the engine box enough air would flow through the areas when you were at a stand-still. I wonder if the radiator cap would work correctly in pulling coolant back from the recovery vessel if the two areas were kept so dissimilar. GPster

enjenjo · July 05, 2013, 10:19:31 AM

This timer will do what you need http://www.ebay.com/itm/H3Y-2-DC-12V-Delay-Timer-Time-Relay-0-10-Minute-10M-w-H3Y-2-Base-Hi-Q-04191-/200707980204?pt=LH_DefaultDomain_0&hash=item2ebb20bbac

nd here is a 12 volt water pump that could be used http://www.ebay.com/itm/NEW-WASTE-WATER-WVO-12-V-UTILITY-PUMP-OIL-TRANSFER-/141010042822?pt=BI_Pumps&hash=item20d4da7fc6

You would need some relays to operate this but it's no big deal

wayne petty · July 05, 2013, 10:48:15 AM

Quote from: "348tripower"got a bypass circuit???
Explain? .

bypass circuit i am talking about...

allows coolant to circulate thru the engine block and heads.. around and around behind the closed thermostat.. picking up heat as it goes around. until the heat in this circulation causes the wax to expand in the thermostat to push the it open.. allowing the hot coolant to exchange with the cooler coolant in the radiator.. once the cooler coolant comes into the circulation inside the engine.. the thermostat closes ... allowing the coolant trapped in the radiator to be cooled by the ram air or cooling fans...

lets look at coolant bypass circuits.. on chevy motors.. its usually the heater hose circuit.. where it comes out of the coolant passage next to the thermostat.. where the water pump has created mechanical pressure above the radiator cap pressure.. this pushes the coolant thru the heater core and back to the inlet of the water pump.. or on a small block into the top of the water pump..

edit
some small blocks have the heater return hose that go all the way to the radiator tank... but if you note on those.. that its goes into the same side thats hooked to the lower radiator hose.. so it just drops down into that tank and right back into the water pump..

this might be the exact fix needed for your truck.. as that would allow trapped air bubbles to circulate right back to the radiator.. instead of causing an air embolism restricting water flow..
end edit

its almost impossible to cool coolant flowing thru a radiator thats flowing at unrestricted circulation speed. look at what nascar guys have to go thru.. changing the amount of tape on the grill ... or sticking the nose of their car out into the wind instead of staying tucked in the draft.. can you imagine what the coolant flow thru the radiator is doing with stewart pumps and the engine running 7200 rpm...

and jeepster... you might have a point about needed to remove trapped air from the engine .. there are a lot of cars with bleeder hoses from the top of the thermostat housing that go to the top of the radiator or surge tank that a lot of new cars have..

coolant recovery tanks catch expanding coolant released by the radiator cap when the system is filled and the expanding coolant is overflowed.. this gets pulled back in when the engine is off. if the coolant recovery tank is properly connected ...

there are coolant bottles?? surge tanks??? they have a real radiator cap on them.. various hoses back to the engine and radiator. these are used on engines lately where the radiator has a cap location below the high spot in the engine..

front wheel drive V6 chryslers have coolant bleed circuits and also bleeder screws to rid the air from the high spots in the engine.. honda all have bleeder screws to rid the engine of trapped air.. even some gm engines like the 3.1 in front wheel drive applications have bleeder circuits and bleeder screws..

348tripower · July 06, 2013, 07:43:25 AM

some small blocks have the heater return hose that go all the way to the radiator tank... but if you note on those.. that its goes into the same side thats hooked to the lower radiator hose.. so it just drops down into that tank and right back into the water pump..

I have this but it is hooked right to the lower radiator hose.

348tripower · July 10, 2013, 06:00:58 AM

So, Can I hook a pump to the hose off the intake and add a fitting to the tank the upper hose is in and circulate the coolant like that?

wayne petty · July 10, 2013, 07:29:36 PM

Quote from: "348tripower"So, Can I hook a pump to the hose off the intake and add a fitting to the tank the upper hose is in and circulate the coolant like that?

i am taking that this is for cool off after shut down to reduce heat soak..

you could do that right at the engine and not have to run a long hose to the front..

what..

yea.. install a vacuum operated heater control valve. thats OPEN at ZERO vacuum.. install that in one of the fitting holes in the front of the intake... then run the hose to the small pump.. and back to one of the multi holed thermostat housings.. with that.. the coolant will flow around the thermostat when the engine is off... sort of a cobble.. but it would be cheep and easy to hook up.. not require any additional holes in your radiator.. and its all under the engine cover.

it would take some creative relay and timers.. to control the water pump and the radiator cooling fans.. but it would probably cool the engine with the engine off..

idrivejunk · July 10, 2013, 08:06:19 PM

I had the same trouble with my Grand Prix, whose headers fit very tight to the stock starter. I installed a 16" aftermarket fan on the front of my radiator, left the dial alone on the adjustable temp controlled switch, hooked it to battery power and stuffed the probe up high in the radiator core near the upper hose. Now when I shut down and temp spikes, the fan comes right on at 215 whether the engine is running or not. Knocks it back to about 211 when running. Makes breeze in the engine bay, thats all it takes on mine. I installed the fan for those trapped in traffic moments but it solved the heat soak issue as a side effect. I know the drill, believe me. Heat soak at gas stations on Power Tour is a "faux pas" and a low buck fix may be a fan like that.

Anyway, I noticed one of the others suggested an" always hot" auxiliary fan too. Mine runs quite a lot after summer shutdowns but never seems to weaken the battery too much. It cycles on two or three times on hot days.

A COE may be a different animal entirely though. Never messed with one.