I have a 1994 Ford CF8000 Cargo Truck. It has a 7.8L Ford diesel with an Allison tranny. The problem is that recently it has been spewing foamy coolant out of the overflow tube on the fill tank. It seems like it overflows at all different times. Sometimes I'll fire it up and drive it about 2 miles to go get diesel, and when I'm stopped at the pump (doesnt matter if engine is running or shut off) it will overflow foamy coolant. Other times it wont overflow until I've been running it half a day. The motor never seems to heat up. The fan clutch had been kicking in more than normal (almost constantly) so I blew the radiator out, which was pretty restricted, and now the fan clutch is back to working normal, but its still overflowing foamy coolant! I put the thermostats in water and heated it up and they opened. The water pump seems to be circulating the coolant good. I dont see any signs of coolant in the oil or anything. I'm stumped. I did just replace the coolant fill tank since it started leaking due to sun rot I think. Could it just be that there is some air in the system and needs worked out, or could I need to flush the system and get some new coolant?
Is the coolant dropping? Another vote for a head gasket.
1996 F-250 extended cab long box five speed. Home made Tymar, 203 Stat, 60 gal in bed fuel cell, 315/75's, no muffler, ebpv welded open 3" to 3" DP, Babies. 290K, still chugging, and still smoking when cold.
UPDATED 1/1/09 Replace so far. 1 LUK flywheel+clutch, 2 thermostats, 2 set of brakes, 1 set of calipers, 5 CPS, 3 sets of tires, 2 Transfer pumps, 1 Injector modual, 1 Computer, 2 Alt, 2 sets of batteries, 1 Water pump, 6 Belts, 1 PS hose, 2 Sets ball joints, 2 set u-joints, 2 carrier bearing, 2 Speed sensors, 1 oil pres sender, 1 temp sender, 4 sets of e-break cables, 1 front fuel tank, 2 rear fuel tanks, 2 set of glow plugs, 7 Glow plug relays, Oil galley o-rings, Turbo pedistal o-rings, EBPV o-rings, 3 sets of Injector O-rings, 1 Vac-pump, 1 new carpet, 1 total paint job.Total $$$ in repairs v/s miles driven = 4.6 cents per mile. Add fuel to that it jumps to 16.5 cents per mile over the life of the truck.
You can buy a kit at NAPA that consists of a plastic bottle and some special liquid. Thing is to get the engine hot and remove the cap. [careful on that part]. Now while the engine is running the 'bulb' is placed on the radiator cap location and the bulb is squeezed to allow the airflow/bubbles from the radiator to enter the test bulb. If the blue liquid changes to a greenish color then the exhaust gasses are entering the cooling system. I have used this several times and I'd say it works 50% of the time. Other mechanic's have used it and had great results with it. Must be just me. [img]/ubbthreads/images/graemlins/frown.gif[/img]
95 F250,XLT, 4WD, Auto Trans,bbshimmed,synthetic trans oil,4:10 gears ,Truck Trunk ,Nerf Bars ,crome Mud flaps, Aux. trans cooler, front diff. drain plug. External trans.filter, trimmed snorkel. American wheels water temp guage, front fuel tank mod,Warn Manual hubs,Putman class 4 hitch 212k mi.
Currently also have 2012 Dodge 4X4 with a Cummins engine.
It is said if you sit by the river and watch the water flow by long enough, your enemies will pass by. This I believe to be true. It is also possible to watch your loved ones pass by as well.
Wife Candi 08/14/07 missing her always
I'll go to NAPA and get one of those test kits. Wouldn't the coolant be showing up somewhere like in the oil if it was a headgasket? I don't have to add coolant very often, so I think I'm only losing it when it spews out of the fill tank......I hope anyway!! I'll let you know what the test kit says.
The oil can absorb a lot of coolant before it starts to show. And if it is a truly "blown" head gasket (as in combustion pressure) then the leak will be from the top of the cylinder to the water jacket. And presumably back though the pressure will be much lower. So long as it doesn't hydrolock, the engine will simply burn this water when it starts, and you will never see it.
usually the only time you will get oil in your coolant is if you have a cracked block maybe a head if you have pressurized oil in the head. I had an old ford with an fe engine in it. I always had choc. milk in the radiator. The usual tell tail sign of a blown head gasket is steam in the exhaust. But it all depends on where the gasket blows.
[/ QUOTE ] Meaning, you blew the junk out of the radiator fins? Or ran water through the radiator core? I think I would also look at possibly having one or more core lines blocked in the radiator, reducing your cooling capacity. I had a Bronco II that used to run very hot. I thought I had cleared the radiator out, until I took it to a radiator shop. The guy took the top of the radiator off and showed me the 3 inch wad of metallic crap that had hardened in the top of the radiator, reducing the cooling capacity about 1/2 by blocking the cooling tubes. Had to get a new radiator, and everything was fine after that. Just my .02 cents worth.
Y2K F250 CC PSD Auto, Short-bed Lariat, Woodland Green/Gold, ordered 07/10/99, born 09/12/99, delivered 10/08/99, BAK RollX bed cover, Bed mat, Zoodad mod, Viper Remote Start Alarm, Fumoto valve, undercoated, 139k somewhat error-free miles (so far) [never back to dealer for anything] , Edge Evolution (60 HP setting), Pioneer DVD/CD/iPod/XM satellite
Repairs: CPS, Water Separator Valve assembly, rear axle bearings, VSS, batteries, brakes, alternator, serpentine belt (x2), all 4 power lock actuators, water pump, air conditioning lines, battery cables
2009 VW Tiguan 2.0 l turbo 200 hp gas engine Wifey's car
foamy coolant=bad head gasket in almost every case.
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Wouldn't the coolant be showing up somewhere like in the oil if it was a headgasket?
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no, not necessarily. it all depends on where the gasket failed. if the leak is between the cylinder and a water passage, then the higher cylinder pressures will blow combustion gases into the water jacket.
The three laws of thermodynamics, simply stated: