PCM Ford 5.8L Block freeze plugs

[James]

The engine in my '98 Ski Nautique 176 was "winterized" last fall. I noticed this Spring that three of the six freeze plugs have popped out.
Could someone out there "toy" with me an reassure me that I MAY not have a problem. Or is the concensus that I have a MAJOR problem. I am not familiar with Ford engines and have done little at this point. There is no obvious cracks in the block or water in the oil.
Thanks for any help. I'm hoping the info I get back is positive.
Jim

[jmo]

RE: PCM Ford 5.8L Block freeze plugs

Are you 100% positive the drain plugs were in before storing it, maybe whomever winterized it forgot to put them back after draining the block? Some Correct Craft dealerships prefer to leave the plugs out over the winter....

[Hollywood]

RE: PCM Ford 5.8L Block freeze plugs

Exactly what plugs are you talking about.

[James]

I'm talking about the freeze plugs not the block drain plugs. There are three on each side of the block. They are about 1 1/4 inch in dia. when installed they apear to be round depressions ( approx 3/8 inch) in the block. When they pop out they look something like a large bottle cap.
Jim

[jmo]

Interesting, I didn't even know there were "freeze" plugs on the block.

[AirTool]

jmo = There has to be freeze plugs. The holes are there to get the sand out of the block after casting.

James = If it were mine,....I'd inspect very closely. Then, put new freeze plugs in and figure out a way to pressure test the system and look for leaks. Disconnect the main hoses and figure out a way to connect a radiator pressure tester or some low pressure compressed air. Even a bicycle pump would work. I ASSUME that all components can take 15 psig....but you should be able to find leaks at a lower pressure. For raw water cooling, if you can hold 5 psi, you should be good. If you have a cracked block, water will flow out the block or into the oil pan.

AirTool

[James]

Thanks.
I'll try the pressure testing idea.
Jim

[James]

Airtool,
If I'm unable figure a way to get a good pressure test, do you think there is any harm with just replacing the freeze plugs and starting the engine to see if I get water in the oil or water coming out of the block. I assume if I do the block is cracked and I 'll need a rebuild anyway.
Jim

[AirTool]

Can you put the water hose on it to start it? That will also provide the pressure. As others have said before...be careful....your water supply could be up at 60 pisg. See other threads on fake a lakes and flushers for more info if you don't have experience with them.

Number one thing is to see if water goes into the oil side.

I would be careful unless you know you will buy a complete short block or better. If you just find a replacement block, you'll need to transfer your old crank, pistions, etc. In that case, you'll want to take care of them.

[James]

Thanks alot for the info.
I'll post my results.
Jim

[AirTool]

One negative to using the water hose and running the engine is that if there is an unlikely crack that would leak water into the cylinder...you won't catch this because water will be coming out the exhaust anyway.

I suggest popping off the necessary hoses and building an adapter to pressure test with air over water. A piece of PVC pipe with a shrader valve threaded in might work nicely.

I know it sounds like a pain....but it will get you the answer straight away.

[James]

Well, after talking to a local engine builder (he told me there's a 99.9% chance the block is cracked so just go ahead and try to run it), I went ahead and replaced the freeze plugs and ran the engine for 15 minutes using a "fake a lake". The engine ran fine with no water in the oil. I may have dodged a bullet. I'm going to lake test it this weekend. I hope if it runs fine then I'll be in good shape.

[WakeSlayer]

I had two frost plugs popped on the 289 in the 68 Mustang I got for my wife. Guessing this was a poor winterization on the PO's part last winter. cleaned up the holes and plugs and put them back in. No problems at all. They are there for that exact reason. We get well below zero many times a winter. With three popped, I would say you dodged a bigger bullet than I.

[AirTool]

The engine ran fine with no water in the oil. I may have dodged a bullet.

There are four places for the water to go:

1. outside the block in to the hull

2. into an oil passage and down to the pan

3. into an intake passage (on the head) then on to combustion

4. into an exhaust passage (on the head) or exhaust bubbling into the water side

While you may not be leaking water into the oil, you still may have a crack. I'm not trying to scare you. Just rig a way to put about 5 psi on it with the engine not running and prove it is solid. Then you will sleep better at night and not someday get stranded far from the shore.

AirTool