engine advice

[mauricedocton]

Also, the old gasket had copper on one side and composite(?) on the other, while the new gasket from VPW has copper on both sides. Would that make a significant difference? Thanks for the help.

[gmharris]

Rotate the crank so the piston is down on the cylinder that was leaking anti-freeze. Check the cylinder wall, if you haven't already done so.

[Gordon Maney]

I pulled the head today and everything looks good - the gasket was intact, with no obvious defects?! Could it have been just a head bolt torque issue? Some of the bolts were harder to break loose than others. One head bolt had a bracket for the spark plug wire tube between the bolt and the head. The bolts did not appear to have any thread sealant on them, but the leak was big, with antifreeze coming out of one of the sparkplug holes and lots of white smoke/antifreeze in the oil. Should I be looking deeper?

You indicate the presence of coolant in the oil and the presence of white smoke, which is really coolant vapor or steam. I'm not sure what you mean by antifreeze coming out of the spark plug hole, I assume you mean with this plug removed. I also assume you mean it came out of that hole when you turned the engine over. I assume you don't mean that you took out the spark plug and it came out like a fountain.

I don't mean to trivialize your concerns, but I am considering what I think the premise was for proceeding this way. If this was a commercial vehicle that had to run every day without fail then we would need to remove the engine, disassemble it, and magnaflux all the castings.

This is a hobby vehicle that does not have to run every day and your living does not depend upon it. Also, there is considerable appeal in the possibility of being able to fix it by replacing the gasket.

So, even though you don't see tracks on the block deck or head surface, unless you guts don't really allow you to do this, put the gasket on it, torque the bolts, fill it with plain water, and run it to see what you've got. If you get a white steamy exhaust and water coming out of plug hole when you turn the engine over that didn't fix the engine and has it come out and apart.

[Gordon Maney]

Rotate the crank so the piston is down on the cylinder that was leaking anti-freeze. Check the cylinder wall.

This, too.

[mauricedocton]

Thanks Gordon and gmharris - I did rotate the crank and there were no visible marks on the cylinder walls and they felt smooth. I guess my premise in asking the question is that I don't want to throw money away by replacing the gasket and all the fluids only to have the same problem because of something obvious that I might not be taking into consideration, especially since the gasket didn't appear to be damaged. One of the sparkplugs had evidently vibrated loose, so when I raised the hood, antifreeze was leaking out around the plug with the engine running. I was just having trouble understanding where the leak was occurring if there is no visible damage to the gasket, the block, or the other components I can see.

[mauricedocton]

flushing the block

I know you'll like this. While I'm waiting for the head to be checked and resurfaced, I decided to see why the block petcock wasn't draining. In one of the engine manuals it says that sometimes you must use a wire to unblock it. After removing the petcock, it still didn't drain - when I used some wire in the opening some chunks of soft brown goo came out.

I began to pour water in the water channel openings on top of the block and lots of brown water and chunk came out. After I poured at least 8 gallons through the engine and it was still coming out brown and occasionally blocking the drain with gunk, I became frustrated and used 3 gallons of hot water with about 12 effervescing denture tablets dissolved in the water; figuring that if it's safe enough for dentures and bridges, it should be ok for water channels.

You should have seen the gunk that came out! I then followed it up with 5 gallons of plain water and it's coming out clear.

[gmharris]

I know you'll like this. While I'm waiting for the head to be checked and resurfaced, I decided to see why the block petcock wasn't draining. In one of the engine manuals it says that sometimes you must use a wire to unblock it. After removing the petcock, it still didn't drain - when I used some wire in the opening some chunks of soft brown goo came out.

I began to pour water in the water channel openings on top of the block and lots of brown water and chunk came out. After I poured at least 8 gallons through the engine and it was still coming out brown and occasionally blocking the drain with gunk, I became frustrated and used 3 gallons of hot water with about 12 effervescing denture tablets dissolved in the water; figuring that if it's safe enough for dentures and bridges, it should be ok for water channels.

You should have seen the gunk that came out! I then followed it up with 5 gallons of plain water and it's coming out clear.

You have only gotten out the loose stuff. If the engine doesn't overheat, you don't really need to worry about it now. But, eventually you will have to pull the freeze plugs to get most of the junk out.

If the freeze plugs are bad, you might as well resign yourself to doing the job sooner than later. But, I'd probably wait until you have to pull the water pump and water distribution tube and do everything at one time.

You will find that one job on these old engines will usually lead to a couple more.

[mauricedocton]

engine advice revisited

This is a follow-up to the head gasket story - hoping it helps someone. I took Gordon's advice and concentrated on the head first. After getting the head magnafluxed and machined (about $75), I replaced the head gasket and all 21 head bolts, using the copper spray and Permatex thread sealant.

I torqued the bolts to spec and did the following test as outlined in the industrial engine manual for the 251/265 engine - disconnect the fan belt, leave off the elbow housing the thermostat, and fill the block with water level with the opening where the thermostat goes - then you run the engine for one minute; if there are no bubbles and the water doesn't overflow the opening, there are probably no internal issues and the head gasket is doing its job.

One of the advantages of this technique seemed to be that I could see the opening from the driver's seat as I started the engine and didn't have to involve my wife, who is not particularly happy with all the time I devote to my Flat Fendered mistress anyway and doesn't like standing around in the cold barn listening to my stream of profanity as I climb all over and under the truck.

It seemed to work - I will post further progress/results. Thanks for all the suggestions and help.

[Gordon Maney]

Congratulations on your good work. I like that diagnostic method.

[Charles Talbert]

Yes you absolutely should be looking deeper.

I don't imagine you will have to look much deeper at all to find a cracked block though, you need to get it magnafluxed. The symptoms you have mentioned in relation to antifreeze in the oil, etc are classic symptoms of a crack. It is about the only way coolant and oil can mix unless your gasket was blown from a water port into a cylinder, which you would have known immediately. I know this isn't good news, and I hope you are the lucky one out of many in that your minor fix may work.

Another issue, you said the head was getting resurfaced; the top of the block deck being flat is equally important. Installing a new gasket and head on a deck that is uneven is fruitless also. Yours may well be as a result of overheating.

I have had many engines in here that the head gasket had been replaced trying to stop coolant and oil mixing, never has it worked a single time to stop that problem. These blocks are notorious for cracking for various reasons, we have seen many cracked ones, and precious few of those were repairable. One other issue you mentioned also points to a cracked block; that is the fact the lower areas of the water jacket were full of crud. High likelihood that someone poured it full of stop-leak trying to stop the very issue you are dealing with. That was the crud you removed, also a high likelihood that the small holes at the rear of the distribution tube are stopped up by the same substance. If you do find a cracked block as I suspect, overheating because of reduced coolant flow is very much the likely cause of the crack.

Good luck with it.

[gmharris]

Interesting. Radiator stop leak won't clog up a radiator in good condition, but I wonder about the slots in the water distribution tube. I'm thinking stop leak is bound to clog the distribution tube unless it is new, and then I think it still might.

I've always thought that a $5.00 can of stop leak was worth a try before more extreme measures. But, now I'm having second thoughts.

[Gordon Maney]

I would never use it.

[wayneh]

That five dollar can of stop leak can cost you hundreds of dollars of labor. When I bought my PW the previous owner told me he could never get the coolant leak fixed, and that it overheated after a while. He told me he replaced the water distribution tube in the block and had the radiator re-cored.

I looked into the radiator and it looked nasty... I did a simple flow test and water should have gushed out the bottom, but it didn't.

So... off comes the front grill assembly and out comes the radiator. I cleaned it with some off the shelf chemicals, and a hose, but when I was done it did look like new.

Then I pulled out the water distribution tube.... The last two slits (for the back to cylinders) were plugged up with a paper like pulp material, which when I think about it is the result of stop leak.

I cleaned he tube and put the thermostat back in and it has not been over 195 degrees since. I still think the block could use a good cleaning, when I installed a coolant filter the opening at the bottom of the block was plugged with junk.

Bottom line: write your congressman to outlaw stop leak! I spent several more months tracking down the leak. I learned at least one of the water pump back plate bolts penetrates the water pump where water is, and you really need to put sealant on those threads and use that cooper washer that comes with the water pump.... (morale of the story: RTFM) (read the flipping manual...)

Wayne

[gmharris]

I can understand why someone would be reluctant to use radiator stop leak. However, my experience has been good, and it's saved me hundreds, if not thousands of dollars.

When it comes time to spend two days pulling apart a dash to replace a leaking heater core, plus the cost of the core and re-charging the A.C., you might think twice about trying radiator stop leak. As I said, it's not going to clog up a free flowing radiator. The particles are too small. I prefer alumaseal which is just finely ground aluminum powder.

However, if you try to fix your 60 year old Power Wagon that has never had the cooling system cleaned, you are asking for trouble. My second thoughts about using it on a Power Wagon are because the rear slots of the water distribution tube are probably easier to clog than the tubes of a radiator.

[mauricedocton]

the saga continues

Here's the latest on my problem. Charles Talbert was correct - the new head gasket did not take care of the antifreeze in the oil or the white smoke from the exhaust. I found a rebuilt 251 from Dan Mininger in Pa. Figuring I had nothing to lose, I tried a non-metallic stop leak compound called Blue Devil that I had researched on the internet. You pour it in and let the engine idle for 50 minutes. After approximately 35 minutes of fogging the southwestern Ohio farm country, the white smoke went away and the engine idle smoothed out - just as the youtube videos showed and the company's website claimed. I plan to replace the engine in the spring - the new engine is from a 1966 FFPW and has the synchromesh transmission and a new clutch; but I thought the Blue Devil was interesting - they claim that it is a permanent fix for cracked blocks and blown head gaskets. It costs about $35 and is available at Autozone. Anyone else used this?