To Pull or not to pull engine?

[GOOSE]

Ok, I have enough money in the bank to address my truck issues and need to plan the method of attack. So bear with me as I lay out my scenario and then fire away.

The engine in my truck has 252,000 miles on it. There is substantial oil in the antifreeze. Cooling system pressurizes prematurely leading me to believe either cavatation or head gasket is problematic. Reminds me that oil cooler should be rebuilt also for good measure. Also note there is 20,000mi on one rebuilt head, the other is origional. Engine occasionally hydrolocks, seems like only one cyllinder, my guess is due to antifreeze dripping into cyllinder. Note: 20,000 mi on new injectors. Antifreeze is not in oil. Engine misses 1 cyllinder for 10-20sec on startup then is smooth and driveable. I typically max at 14psi boost and use this truck to daily drive and tow/ heavy work on weekends. Intercooling and Moose mods are future possibilities.

I want to replace head gaskets and upgrade to studs, and rebuild 2nd head.

Questions: Pull heads and do work with engine in truck?
Pull engine, do work, clean, paint, reinstall?
Bearings; main, rod, cam?
Make jig out of 1/2 lexan to pressure test cyllinders for cavatation; not worry if head gasket is apparantly at fault?
Any other things to reccomend?

Note: I have parts engine with 130,000mi. runs. Seems to need gp's, IP, and injectors. Rebuild this one or one in daily driver? Would lose good spare if went this way.

This thread will be referenced and taken into great consideration. Thanks in advance for all of your help.

 

[94f450sd]

toss the spare in it.then rip the old motor apart to see whats wrong with it.rebuild it slowly as the money comes in.do the studs and gaskets to the spare while its out and the truck is still driveable.do everything it needs before ripping the old motor out,this way all ya gotta do is pop one out and pop the other right in.should take the worlds dummest mechanic a day to swap that motor out.

took me a total of 9 hours from start to finish to cut one out of a van,new gaskets,seals,and return lines,pull the junk motor from the truck and drop the van motor in it.customer damn near crapped is pants when i called him the next morning to come up with my cash and come get his truck.

 

[1993 f-250]

i really think that we should get some more input on this. cause i also have a spare motor with only 80,000 miles on it. i stole the ip off it and the gp controller to put on the one in the truck. the motor in the truck has (As far as i know its the stock motor) a little over 228,000 milees on it. ive taken good care of it since i have owned it and its drinkin antifreeze. no clue where or how but i just checked the kother day as i was changing out the belt tensioner and noticed that it was wellll below the fins in the radiator. dont really have the money right now to do this as i wont have a job till the summer and will be going off to college next fall but its still something that i want to do. still curious as to where the antifreeze is going. not really sure.

 

[starmilt]

Personally I would do as he said, do what you want-need to the spare and swap them then repair yours for a spare. After all isn't that why you have a spare. lol

Explain this test jig out of half lexan if you don't mind.

 

[94f450sd]

the lexan is a chunk of clear plastic (plexiglass,basicaly)cut and drilled so it can be bolted and sealed to the block so you can pressurize the water jackets and check for leaks from cavitation or cracked block.but a cracked block may not show up using this method as the crack may not open enough to leak till its warmed up.

 

[94f450sd]

i really think that we should get some more input on this. cause i also have a spare motor with only 80,000 miles on it. i stole the ip off it and the gp controller to put on the one in the truck. the motor in the truck has (As far as i know its the stock motor) a little over 228,000 milees on it. ive taken good care of it since i have owned it and its drinkin antifreeze. no clue where or how but i just checked the kother day as i was changing out the belt tensioner and noticed that it was wellll below the fins in the radiator. dont really have the money right now to do this as i wont have a job till the summer and will be going off to college next fall but its still something that i want to do. still curious as to where the antifreeze is going. not really sure.

id get started on yours ASAP.this way its done and ready to go in by the end of summer.do the motor swap a couple weeks before you go back to school so you know you have a reliable vehicle while your in school instead of wondering how long its gonna last.plus while youre away for college you know you wont the time and/or the money to do a swap if the motor pops on ya.

 

[starmilt]

i really think that we should get some more input on this. cause i also have a spare motor with only 80,000 miles on it. i stole the ip off it and the gp controller to put on the one in the truck. the motor in the truck has (As far as i know its the stock motor) a little over 228,000 milees on it. ive taken good care of it since i have owned it and its drinkin antifreeze. no clue where or how but i just checked the kother day as i was changing out the belt tensioner and noticed that it was wellll below the fins in the radiator. dont really have the money right now to do this as i wont have a job till the summer and will be going off to college next fall but its still something that i want to do. still curious as to where the antifreeze is going. not really sure.

I would investigate the leak before I decided what you are going to do. Is it starting and running fine, it it blowing white smoke, any antifreeze. Your loss of antifreeze could be as simple as a radiator cap.

 

[GOOSE]

My truck chews antifreeze as well. A 30mi round trip to and from work will eat up about a gallon of antifreeze. Any white smoke is dark grey in color due to the black smoke from maxxed IP. I have noticed boost is down about 2psi to 12pounds. I have a gut feeling that seeing a faulty head gasket is my best case scenario at this point as it may help to rule out the worm.

Yes, I was going to trace a head gasket onto lexan and have it cut on a flowjet possibly to bolt down in place of the head. I was going to put a schrader valve and pressure gauge on each cyllinder and pressure test each cyllinder one at a time. An average leakdown rate over a given time will let you see if pin holes are in water jackets. Also a compression test before teardown could be compared to this and the condition of head gasket to give further verification of a potential problem and its whereabouts in the motor. I haven't done this before. My uncle is a machinist I watched him do something similar so I applied it to suit my needs. I figured a higher pressure test on the cyllinders may get a better result than a lower pressure on the water jackets.

I guess this is going towards a way to rule out cavatation without disassembling the block and sending it out.

 

[94f450sd]

you already done the heads and gaskets,i doubt its a gasket or head problem unless you didnt send the other head out to be planed and pressure checked(dont know why people do that).id say its in the block.

when does it hydrolock?over night?pop the glow plugs out and turn it over to see wich cylinder the antifreeze or whatever is coming out of.then youll know what side its on and what area to look at for the leak.

 

[GOOSE]

Only had one head done because GP and injector broke off in it. I Bought the truck from Oregon and it had issues. It was $900 more to ship the truck to NJ in not-running cond so I put that money into getting it running. Long story in short form, I just wanted to get the truck home. It ran good for a while. I turned up IP screw and boost went from 11psi to 14. I hoping that towing heavy loads with this much boost and reused head bolts may have been recipe for head gasket failure. Even though bolts are listed as reuseable, this may be beyond their abilities.

EDIT: thanks for pulling GP suggestion. hydrolocks after a few hrs at times.

 

[65sixbanger]

In my opinion you can never go wrong by pulling a motor. If nothing is wrong, then you at least get the piece of mind knowing your ok. If the motor needs some work, in all reality its not that expensive to make it dependable again. I would replace all bearings and if nothing else the rings. Why not?? they are pretty cheap.

 

[Diesel JD]

I'm going to guess it's the block worm. 7.3s do occasionally blow head gaskets but 12-14 psi with a 7.3 really isn't that bad. Personally I would rebuild the engine on the stand, but if it's hydrolocking you may be soon to be out of time. You may not be far from doing irreparable damage, so there is a good argument to be had for just tossing the spare in and taking your time to fix your current engine. I you do that I wouldn't do anything to the spare engine unless something is already wrong with it.

 

[damac]

How are you monitoring the coolant system pressure?

And how can you tell if your truck is hydrolocking?

We are going through something kind of similar, only thing I can add right now is that our lowest compression was 385 with a high of 440

Also a few months ago when we got the truck we took the oil cooler out, put new orings and a new gasket set. After we got the cooling system clean we had no more exhange for 2,000+ miles but now it is back bad with oil and sludge after a slight runaway incident we had on the freeway a couple weeks ago.

I cannot see a hint of leaks on the outside of the oil cooler, no coolant in oil that I can see and the manual oil gage still shows the same patterns, like 40+ oil pressure steady when on the pedal going on the freeway with a load.

So I have no idea if that means our oil cooler is still ok. If so maybe yours is as well and it makes me wonder being a non techie, just what exactly else could lead to so much oil exchange into the coolant without it happening the other way around. Maybe we have the same issue, but we aren't quite ready to tear it all apart yet.

 

[hesutton]

Goose, I'd pull the engine. I will be much easier to work on and you can easily examine the motor for other issues that will be a pain to do with leaving it in the truck.

I'd pull the whole front clip as one piece. It will be easier and less compicated that pulling apart the front of the truck to get the motor out.

Heath

 

[1993 f-250]

I know that i dont have any antifreeze mixing with my oil and its not hydrolocking or missing any at all. i think that i might have bad head gaskets. also i know i need to tighten my valve covers cause they tend to loosen. anyone else have this issue? my moms exboyfriends brother and dad had a 6.9 and a 7.3 and said that everytime they changedd the oil they would have to snug em up. Think this might be part of the issue? should I just go ahead and replace the head gaskets? what all is involved with this? also its starting fine. well. i think my timing is off a very fine fuzz or i got another gp goin down. all the smoke that my truck makes is a puff of black once the motor catches and when i stand on the go pedal(ip is turned up two flats)