93 4.0 purging coolant out of reservoir

[just4today]

I have recently acquired 93` Ranger 4.0,5spd. Truck has not run for awhile . So , i cleaned and gapped plugs , installed used starter , drained coolant , cleaned reservoir , pulled t-stat , refill w/ water and oil change . The oil was dirty but not contaminated . So , truck runs - sounds good,slight tick, no knocking or smoke wagon .
I go in town buy thermostat and install it and add about 1 - 1 1/2 quart coolant . Truck starts right up , heater is on high and blowing hot , gauge is showing about half , then after just a few minutes the reservoir starts overflowing probably a gallon or so .
To run w/o t-stat i simply installed rubber seal w/o mechanism . Installing new one i cleaned both surfaces and placed spring side towards motor .
Any thoughts on what this is ? Thanks .

 

[just4today]

I have done some searching - likely dealing with head gasket or crack . I get it now - cheap truck , expensive to run and drive . I`ll report back after i have removed heads . Cheap things first right - free to disassemble .
This site has been very helpful . Search does work ! Thanks to all !

 

[JohnPi]

I'd check the Radiator cap first before doing something drastic like pull the heads. You may have damaged it just taking it off and putting it back on during the coolant flush.

Is the engine running funny?

 

[just4today]

I spent a few minutes with it this morning . I swapped cap with known good one , looked for collapsed hoses , leaks , and within a few minutes here comes coolant from reservoir . Today i watched the exhaust closely - started with little or no output , gradually increasing , assuming this is steam - bad head . Right ?
Not running funny , slight tick , holds good idle , has power , plugs normal . When i removed plugs - i took old box and made six slits with razor knife , then with a sharpie labeled 1 - 6 . Compared them 1 - 6 , all had carbon deposits , none were really clean , brushed and gapped .054 .
I found fel-pro head gasket set on ebay $50 . So , figured i would tear down , clean and inspect .
With some searching on this site - I have come to expect cracked head , worn push rods - which would explain tick . Thanks .

 

[Stranger ranger]

First of all, you need a second opinion, not just us reposting to your input. Let someone else hear and see whats going on. Do not replace the head gaskets unless you do a pressure test and it shows that is the problem. The tick could very easily be the injectors, as they are pretty noticeable. However, where is the tick, meaning, what rpm range? Does it only tick when you put a load on the motor? How many miles are on the motor?

 

[just4today]

I`ll get back out there soon and do compression check . I am suspecting low cylinder or two . I could get radiator pressure tester this weekend , but may not need it .
w/o t-stat system flows well . Once installed provides blockage - system pressurizes before t-stat opens - therefore relieves into reservoir . I am thinking exhaust is source of pressure . I`ve always thought oil/water mix or spark plugs would reveal head issues . I`ll keep testing . thanks .

 

[JULIUS]

Radiator pressure test is not a for sure sign of a blown gasket.I had the exact same problem a few years ago with a little suzuki samarai.I had the radiator test done and it held the pressure for 20 mins.my fan's clutch wasn't working and the motor overheated and cracked the gasket.I drove the truck for 2 more years, constantly adding water everyday until I traded it to a dealer.