Using sealer in oil to fix blown head gasket

[ExploringNC]

I'm starting to have some issues with my '91 and I'm thinking it may be a blown head gasket. My oil pressure had started to run low, less than the N on normal. A few times truck idle would get real low and fall even more and when I revved it up pressure would come back. I changed oil and filter thinking filter blocked, pressure started out at about the O in normal then after a few days it went back. Truck just doesn't sound right, like plugs fouling out. Now at idle I'm getting smoke and the more it sites idling the more it smokes, rev it up and smoke startes to clear. I'm not sure if this is related or not but I finally got my fuel filter replaced and now oil pressure stays at R all the time. I pulled a KOEO of I think 414 but I can't find that code number. The truck sat for about 4 years with a blown head gasket and I had the head shaved and it's ran good for about six months, could I have a leak in a head gasket allowing oil into a cylinder at low idle? No oil in coolent and no coolent in oil but temp seems to be running low. Fuel mileage is also really bad. Could it be anything other than a head gasket?

Has anyone used a block sealer that you run in the oil? Seen this in a parts store for $64 a bottle and since this is my DD and the weather is real crappy how much harm can it do? Product says it fixes cracked or warped heads. I don't want to put this in if its going to cause more harm than good.

 

[IZwack]

Remove the radiator cap and do a compression test on at least the cylinders with fouled plugs. Or remove the radiator cap and pressurize the cylinders with the fouled plugs using an air compressor (bubbles should surface at the radiator).

 

[ExploringNC]

Remove the radiator cap and do a compression test on at least the cylinders with fouled plugs. Or remove the radiator cap and pressurize the cylinders with the fouled plugs using an air compressor (bubbles should surface at the radiator).

I havn't been able to get to my buddies shop with all the tools I need and the weather lately has made it impossible to work outside but that will have to be done. Ever see a KOEO 414 code?

 

[Wrench]

After four years of sitting how were the cyld walls - Rusted?
Did you inspect both banks? Was there any signs of coolant in any bore?
Did you shave both heads so as not to mismatch the head to intake fitment?
Was (were) the head(s) pressure tested before re-install?
What color was the old oil?
Did you use the old head bolts?

 

[ExploringNC]

After four years of sitting how were the cyld walls - Rusted?No antifreeze in any cyl so nothing had rusted
Did you inspect both banks? Was there any signs of coolant in any bore?Only one cly had a foiled plug so I only did the one sideDid you shave both heads so as not to mismatch the head to intake fitment?
Was (were) the head(s) pressure tested before re-install?No
What color was the old oil?Normal for old oil, not milky at all
Did you use the old head bolts?No

Paid only $200 for it and wasn't really going to put much more into it not knowing how bad/good the rest of the truck was. Actually got the thing running pretty good, but now it's starting to act up a little. I think I've narrowed most of my problem down to my fuel pump and a vacuum leak somewhere. Truck has a power steering leak that has soaked motor with oil and grim and we've had yet another snow storm so I have'nt really gotten out to troubleshoot real well.