Sorry for the book, but I'm writing this like you haven't done this kind of thing before but you have tools and some skills.
If you're worried about the heater cores, bypass them with some straight hose that loops back.
K-seal or Blue Devil seem to work the best from what I have heard.
Follow the directions to a T, then you can try a few tricks.
1. Most often it is a leaking gasket, not a cracked head, especially if you had the timing too far advanced and rattled it for a couple thousand miles. Unless you scope the cylinder and see a crack, I'd suspect a gasket a lot more than a head casting. If you were driving around with the timing too far advanced, you probably pushed the gasket between two cylinders out of position with pre-ignition, probably between cylinders 3 and 4. That gives two options. Drive it and hope, or yank the head and replace the gasket. If you are trying to drive 1000 miles home, across the mid-west in July, I'd be hard pressed not to just get a hotel where or nearby a place you can work on the rig, yank the head and fix it or tow it home with a U-Haul.
2. If you choose to drive, retard the timing a little if you haven't already. Rattling it is going to kill it that much faster. If you don't know which cylinders are failing, you can do a power balance test to see if you can figure out which cylinder, or pair of cylinders is most affected. If they did a compression test any cylinder that was low is suspect, especially if they are side by side. If you do a power balance test and have two side by side that make very little difference in idle speed when you pull a plug wire, that is where you will find your problem. Then you have a choice. You can re-torque the head bolts to spec and go a little higher than OEM spec to try and band-aid it or drive it as-is.
If you want to re-torque, you can do this without pulling the bolt all the way out. If they are crusty feeling when you loosen them, loosen until you can shoot some very light oil down the hole under the head, working it back and forth several times till loosens up, then re-torquing to spec, plus 5-10 ft/lbs. Any light oil will work, PB Blaster, ATF etc. will be fine, motor oil if it's thin will also work but may not flow down the threads very well. If you find a couple loose ones as you are breaking them loose or a bunch of them that loosen very easily, that is probably your problem. This only works about half the time I've ever tried it but some help is better than none.
forum.ih8mud.com
If you want to run it as-is, and you identify cylinder(s) that are affected, you can pull the plug wires on those cylinders and give the head gasket in a bottle trick a go. You can do this 2-ways. Fast-Idle it with no load for an hour, watching the temp guage and allowing it to get hot without loading the engine or you can drive it normal. Beware, if you have a catalytic converter, this can melt the insides and make a bad situation worse, so proceed with caution. Anytime you have unburnt fuel going into a Cat, you can melt it pretty fast, like minutes, not hours. If you don't have a Cat, the exhaust will get hotter, but it will probably be just fine as long as you aren't flogging it. The advantage of trying to stopping combustion in cylinders that are leaking is that there won't be pressure trying to blow the gasket out, while you get it hot enough and drive it long enough that it can try to fill the gaps with the stop leak. Going to be a total dog with no power, but it will run down the road faster than walking. Probably 20-30 miles of driving and getting up to temp will get the sealer started working. 2nd option is just leave the plug wires on the cylinders and drive super easy. Every power stroke under load is going to want to push that gasket out more or push the sealer out of the crack, if that's what you did.
Pro's and Con's to having the radiator cap on.
Pressure will push the sealer into the crack or spaces where it can try to seal. If you put the cap on, you can also pressurize the cooling system too much with combustion gases and it will blow the top tank off the radiator or find a weak point in a hose / fitting. Your call. If I was idling it or fast-idling with no load, I'd leave the cap on and run it for an hour to try and get the sealer to work by forcing it into the hole with water pressure. If you are loading the motor by driving, I'd leave it loose, but not off to hold as much water in the system as possible without building too much pressure. Try to drive at a steady pace no more than 1/4 throttle. Coast down hills if you can rather than using engine braking to prevent high vacuum in the cylinders from sucking water in, if you left the cap off.
These motors are very hardy. They can tolerate a lot of abuse and with such low power output, they can run with hurt parts for quite a distance.
If I were trying to get home, I'd probably try to stay off the freeway where you can cruise along at 40-45 mph, and avoid lugging the motor or flogging it as much as possible. As a last resort, you can pull the hood off to try and get more air through the radiator if you have a place to stow it and see if that will keep it cool enough to push on.
If you're worried about the heater cores, bypass them with some straight hose that loops back.
K-seal or Blue Devil seem to work the best from what I have heard.
Follow the directions to a T, then you can try a few tricks.
1. Most often it is a leaking gasket, not a cracked head, especially if you had the timing too far advanced and rattled it for a couple thousand miles. Unless you scope the cylinder and see a crack, I'd suspect a gasket a lot more than a head casting. If you were driving around with the timing too far advanced, you probably pushed the gasket between two cylinders out of position with pre-ignition, probably between cylinders 3 and 4. That gives two options. Drive it and hope, or yank the head and replace the gasket. If you are trying to drive 1000 miles home, across the mid-west in July, I'd be hard pressed not to just get a hotel where or nearby a place you can work on the rig, yank the head and fix it or tow it home with a U-Haul.
2. If you choose to drive, retard the timing a little if you haven't already. Rattling it is going to kill it that much faster. If you don't know which cylinders are failing, you can do a power balance test to see if you can figure out which cylinder, or pair of cylinders is most affected. If they did a compression test any cylinder that was low is suspect, especially if they are side by side. If you do a power balance test and have two side by side that make very little difference in idle speed when you pull a plug wire, that is where you will find your problem. Then you have a choice. You can re-torque the head bolts to spec and go a little higher than OEM spec to try and band-aid it or drive it as-is.
If you want to re-torque, you can do this without pulling the bolt all the way out. If they are crusty feeling when you loosen them, loosen until you can shoot some very light oil down the hole under the head, working it back and forth several times till loosens up, then re-torquing to spec, plus 5-10 ft/lbs. Any light oil will work, PB Blaster, ATF etc. will be fine, motor oil if it's thin will also work but may not flow down the threads very well. If you find a couple loose ones as you are breaking them loose or a bunch of them that loosen very easily, that is probably your problem. This only works about half the time I've ever tried it but some help is better than none.
can someone resolve a question about retorquing head bolts on a 2F?
I'm working on doing a vavle adjustment and head bolt retorque, and I came across some contradictory advice when I searched "retorquing head bolts". Under the post titled" Head bolt retorque - warm or cold" it was suggested that this should be done on a warm engine before adjusting the valves...
forum.ih8mud.com
If you want to run it as-is, and you identify cylinder(s) that are affected, you can pull the plug wires on those cylinders and give the head gasket in a bottle trick a go. You can do this 2-ways. Fast-Idle it with no load for an hour, watching the temp guage and allowing it to get hot without loading the engine or you can drive it normal. Beware, if you have a catalytic converter, this can melt the insides and make a bad situation worse, so proceed with caution. Anytime you have unburnt fuel going into a Cat, you can melt it pretty fast, like minutes, not hours. If you don't have a Cat, the exhaust will get hotter, but it will probably be just fine as long as you aren't flogging it. The advantage of trying to stopping combustion in cylinders that are leaking is that there won't be pressure trying to blow the gasket out, while you get it hot enough and drive it long enough that it can try to fill the gaps with the stop leak. Going to be a total dog with no power, but it will run down the road faster than walking. Probably 20-30 miles of driving and getting up to temp will get the sealer started working. 2nd option is just leave the plug wires on the cylinders and drive super easy. Every power stroke under load is going to want to push that gasket out more or push the sealer out of the crack, if that's what you did.
Pro's and Con's to having the radiator cap on.
Pressure will push the sealer into the crack or spaces where it can try to seal. If you put the cap on, you can also pressurize the cooling system too much with combustion gases and it will blow the top tank off the radiator or find a weak point in a hose / fitting. Your call. If I was idling it or fast-idling with no load, I'd leave the cap on and run it for an hour to try and get the sealer to work by forcing it into the hole with water pressure. If you are loading the motor by driving, I'd leave it loose, but not off to hold as much water in the system as possible without building too much pressure. Try to drive at a steady pace no more than 1/4 throttle. Coast down hills if you can rather than using engine braking to prevent high vacuum in the cylinders from sucking water in, if you left the cap off.
These motors are very hardy. They can tolerate a lot of abuse and with such low power output, they can run with hurt parts for quite a distance.
If I were trying to get home, I'd probably try to stay off the freeway where you can cruise along at 40-45 mph, and avoid lugging the motor or flogging it as much as possible. As a last resort, you can pull the hood off to try and get more air through the radiator if you have a place to stow it and see if that will keep it cool enough to push on.
