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Topic: Coolant system drain plug on 5.0 (Read 2072 times) previous topic - next topic

Coolant system drain plug on 5.0

I'm planning to put on Goodyear Mustang HO blue radiator/heater hose set on my 87 TBird 5.0. I'd like to drain both the radiator and engine. I keep reading about a drain plug on the engine block but have not seen or read any description of its location. Where is it? ...and after all these years is it a wise choice to even touch the thing? For that matter should I even attempt opening the radiator petpen 15 or just take off the bottom rad hose and leave it at that? Just trying to avoid any unneccessary lost time. Your experiences are appreciated.
87 Sport with HO cam, 19# injectors,TB+Upper Intake,87 Mustang EEC, Cloyes double roller timing chain, Kirban adj. fuel regulator and Autometer fuel pres. guage, HO shorty headers + LSC H-pipe and Dynomax Super Turbo lers, Ford Racing 9mm wires, K&N filter / no air resonator, 8.8 XR7 Diff., V rated tires, Project ongoing.

Coolant system drain plug on 5.0

Reply #1
I've honestly never heard of any engine having a coolant drain plug on the block. I suppose it's possible, but I doubt a Ford engine would have one.

Anyway...draining via the radiator petpen 15 is a little easier and tends to keep gunk from getting into the coolant. But it takes forever. And don't forget that the petpen 15 has left-hand threads. That's how I broke mine...tried to turn it the wrong way. oops.

I just recently bought a small siphon pump from harbor freight which I hope to use to drain my coolant when I install my new radiator. No muss, no fuss, no spilled coolant- I can just pipe it straight into some empty jugs.

Garrett H.
'94 F250 XLT- 4x4, 5 speed, 7.3 IDI Turbo Diesel, 4" intake, 4" exhaust, 5" turnout stacks, manual hubs, etc.
'87 Thunderbird Turbo Coupe
Engine, wheels, tires, etc!
Exhaust sound clip
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Coolant system drain plug on 5.0

Reply #2
If you have a large shop vac you can use it to "suck" the coolant out of the engine.
One 88

Coolant system drain plug on 5.0

Reply #3
RE: the block plug, I didn't think there was one, although Haynes and the Ford service manuals mention it. Thanks for the tip on the petpen 15, I would of turned the wrong way as well. I think I'll play safe and just make a mess by taking off the bottom hose and call it a day. Thanks
87 Sport with HO cam, 19# injectors,TB+Upper Intake,87 Mustang EEC, Cloyes double roller timing chain, Kirban adj. fuel regulator and Autometer fuel pres. guage, HO shorty headers + LSC H-pipe and Dynomax Super Turbo lers, Ford Racing 9mm wires, K&N filter / no air resonator, 8.8 XR7 Diff., V rated tires, Project ongoing.

Drain Plugs

Reply #4
On my '89 5.0L ther are two block drain plugs.  Passenger side front of block just above the pan rail, and drivers side at rear of block down low.  There is also a petpen 15 on lower radiator tank, passenger side.  Good luck,  Fred

 

Coolant system drain plug on 5.0

Reply #5
Well I've done the dirty deed today. I opted to just use one of those cheap hand squeeze siphon pump hoses to empty the radiator and thus got only fluid gushing from the block side when I undid the bottom rad hose. A bit less of a mess. Now to carry on with the rest of project HO cam.
87 Sport with HO cam, 19# injectors,TB+Upper Intake,87 Mustang EEC, Cloyes double roller timing chain, Kirban adj. fuel regulator and Autometer fuel pres. guage, HO shorty headers + LSC H-pipe and Dynomax Super Turbo lers, Ford Racing 9mm wires, K&N filter / no air resonator, 8.8 XR7 Diff., V rated tires, Project ongoing.