head gasket

[Rozann]

we have removed everything to replace the head gasket we took in the heads and they are shot so my question is how do we check the lower part of the engine to make sure it's OK to put brand new heads on?

 

[RobbieD]

At minimum, a close visual inspection of the cylinder bores for scratching or galling.

With the motor still of the in the chassis, doing a visual inspection, and measuring with a mic or plastigage if suspect, of a few of the bearings would be difficult. Without pulling the block and further disassembly, if the cylinder bores look OK, and the truck didn't use a lot of oil or have any knocking sounds before, I'd just put the heads on see how it does afterward.

 

[pjtoledo]

a few details on the shot heads please., like why are they shot? why did you pull the heads?
how many miles?
what did the spark plugs look like?
right now would be a good time to pull the cam sync unit for inspection.

 

[MaicoDoug]

Without the motor assembled with the head on & sealed as is, you still need to test the compression, & check the oil pressure, along with the visual inspections mentioned above. It would not be a waste of time to re-install the head with a new head gasket after the valves and valve guides are serviced, & the head milled for flatness and check that oil pressure that should of been done before disassembly. There is a trick.....to test by adding oil into the spark hole looking at a compression gauge. 1) check the compression, 2) next add a tsp of oil and take note of any added compression reading. The addition of oil tell you that the piston rings are worn. You also have the valve and valve stem seals that will also leak after so many miles.

 

[Rozann]

This is horrible! So long story short. Truck has different engine because I loaned my truck out and it over heated and cracked block. This different engine is crap as well. The radiator overflow keeps gurgling and filling and cap pops off when I drive it. Took to a mechanic and was told this: coolant overflow smells like combustion gases. Used a block tester and failed. Head gaskets are leaking, may be head gasket or cylinder issue. Engine has oil leaks. So we took off heads and had them checked and they said they are cracked. No clue how many miles on this engine. And spark plugs and wires are new.

 

[RobbieD]

I'm sorry, but I wouldn't feel confident in that engine block if coolant got into the oil and it was run for any amount of time.

Before going to the trouble (and expense) of bolting on new heads, new gaskets and bolts, I'd want to pull the motor, remove the oil pan and crank and rod caps and check all of the bearings.

At this point, even though it's a bitter pill, if it were me, I'd look around and price a reman short block to use those heads on.

Others here may have better suggestions, though.

 

[Rozann]

Well we do know that the coolant did not get into the oil. He checked the cylinder bores and said they are not scratched up. I am unemployed looking for a work from home job because of this dang truck. I cant afford another engine and cant afford to have it fixed at a shop. Just trying to fix ourselves at this time. I just dont understand why the overflow gurgling thing is happening. There is no other fix for that? Seems so minor.

 

[RobbieD]

I've been there, too, and understand.

Soooo . . . if the bores look good, and you're sure that coolant didn't contaminate the oil, it's worth taking the chance on putting the heads on, and seeing if you have a serviceable engine.

The overflow gurgling is a sign of cracked heads or a blown head gasket; that should clear up if the head installation is successful.

I wish you the best of luck on it!

 

[MaicoDoug]

Rozann I feel for ya. Everything you're going through with the Ranger is pretty typical. Every motor has it's good & bad. A mechanic gets to see stuff that others don't. Or don't want to see I should say.

My overflow coolant looked terrible, turned out to be a one way pressurized transmission cooler fluid leak in the radiator. The ATF on the dipstick looks perfect. Dodged that bullet. It was only because the transmission is cooled with a submerged coil of tubing inside the radiator. So when I saw a red milkshake looking at the surface of my radiator water (coolant), I be damned. Lucky I caught it in time. Exhaust or combustion gasses can be detected in radiator water with an electronic sniffer. That is the source of your gasses or gurgling. As long as you have the heads off, get em fixed and run thicker oil if the crankshaft journals are worn. If you see a jump in compression with a touch of oil after the heads are back on, then the rings may need some attention down the road. You've taken the time to remove the heads, so half that jobs is already done. I hope the engine doesn't have a history of burning oil. That's what looking at the spark plugs will tell you. I think you'll be alright with the new top end-head job.

 

[Rozann]

Thanks to you all. I really like the truck and just want to drive it again like normal. I will reply with the results here in a couple days. Hopefully something good happens.

 

[superj]

you get the bubbling in the radiator because the combustion chambers have a higher pressure then the cooling system.

so the gases from combustion are forcing their way into the coolant system, pushing coolant into the overflow, and popping off your 12-14 pound radiator cap instead of blowing a line off something. the combustion chambers are compressing to over a 100 pounds versus that 12-14 pounds, is the reality of what was going on at that point