I recently did cups, injectors, and push rods on a friends 2000 F-350. All his push rods had slight bending to them with number 7 and number 8 having bad bent push rods on the exhaust iirc. Anyhow the bends to the other 14 push rods were minor, but still. Went in there thinking it was just an injector as he has 263k on the clock and something let go a few weeks back and he was dripping fuel from the tailpipe. When I pulled the push rods the exhuast valve on #7 was stuck, so I figured it was the mangled push rod causing the fuel in the tail pipe or the injector stuck open and thats what bent the rod. Hes had push rods done once, possibly twice before (long store, previous mechanic, supposedly replaced an injector one of the times but all his injectors came out looking the same (another long story))
Anyhow I tapped the valve and it popped free, and I put new ford push rods in and rotated the engine around and nothing seemed to bind. Now I WANTED to pull the heads cause I figured something else was going on, but he didn't want to. So just put it back together and get it out the door. So thats what I did. Everything was good and the truck ran great cept for one remaining problem. A leak from the rear of the engine. Now I had changed EVERYTHING gasket/oring related in fixing this, and his previous mechanic had done the pan 5 years ago. He pulled his transmission hoping it was rear main, since rear main, cover plate, and oil pan were the only things left to leak. Mind you we already knew his oil pan leaked up front cause you could see bubbles comming from the u shaped part, but I digress.
Yeah yeah I know head questions, I'm geting there, I think the back story is important to know before answering....
Tranny out, I refused to do it on the broken concrete floor in his garage, so he did most of it, which I am glad he did cause he found out how much it sucks working on his dad's cold broken floor, with crappy light and little room to work...I digress again... Soon as the tranny was out I popped under there to do clutch and flywheel and found it was his oil pan, like I had suspected, but had hoped I was wrong. He wanted to just go in and do main seal and hope that was it, hence why HE did the tranny himself, well I assisted a bit.
So at that point it was realized that the engine had to come out, and the next afternoon it was out. Oil pan RTV came off completely stuck to the pan, never bonded to the block, again previous mechanic and his rush to do things. It was obvious where the leaks were thanks to the suggestion he pour in dye before pulling the tranny. So while the engine is out I take a minute to pull valve covers and check some push rods.....
#7 has slight bends to both rods, very minor, but shocking to see (well not entirely as I wanted to pull the heads before) after only 300 miles of driving, OH and I almost forgot, he has a BD exhaust brake, which was disconnected d for the 300 miles right after the injectors were done. So this pretty much clinched it that there is a vlave train issue. So off with the heads, no other push rods showed signs of bending, but i found 3 pistons have made contact with valves, #7 exhaust valve STAMPED its International part number into the piston.
So with this it was decided I'm doing an overhaul to his engine and this brings me to the head questions ect. Got comp 910's and .015 and .030 shims for the heads, and swamps stage 2 .120" wall thickness push rods coming. Going to measure installed height of springs so I can see if there is any problems with the springs being weak or something holding back the valves. Given that no damage is apparent (still some more cleaning to do) I was planning to have the heads tanked and checked at Napa before doing much else.
So questions....
#1. If heads are being hot tanked at Napa, should I remove all valves first, so that all the crap can be cleaned out and seats can be checked?
#2. If heads are being tanked, does that mean I have to replace the brass injector cups again? I am unsure of the cleaners they use and how that would work with the Loctite 620 and the new brass. I am leaning towards yes they will have to be done again..and as such I should just pull them out before having the heads cleaned.
#3. Valve guides? At 263k miles and some piston to head contact, I was thinking valve guides would be in order, especially on those that made contact enough to leave good marks on pistons. If so how does one replace them as I have not found anything on doing it and the ford manuals say nothing except for stem seals. Obviously if there is much play to the valve stem in the guide they need to be done, but how or is that a better left to Napa's machine shop?
#4. New valves? Most of his valves and seats look really good, and he had no compression issues, as far as I could tell. His truck ran good right up till it didn't, and never had starting issues or any appreciable smoke on startup ect. Could start without glow plugs even before the injectors were done, down to about 30 to 40F. My gut says replace valves on cylinders with contact, but small part of me says do them all, but they are pricey. Granted he's balls deep already, and in my mind doing a full head rebuild with all new stuff would be an investment in longevity, even if the block were to ****, the heads could go on a new short block down the road if needed.
#5. Should pistons with contact be changed? Going with my gut I am gonna say no, cause the push rods turned pretzel on the bad cylinders and so far I cannot see any cracks. Kinda thinking that a good part of the other 14 bent push rods were from his excessive use of the exhaust brake (like leaves it on ALL the time, even while not loaded down or towing) but I could be wrong.
Ok I think thats all so far, this would be my first rebuild of diesel heads or a diesel engine. Done tons of gassers, and a load of gas aluminum heads, but never cast iron.
Anyhow I tapped the valve and it popped free, and I put new ford push rods in and rotated the engine around and nothing seemed to bind. Now I WANTED to pull the heads cause I figured something else was going on, but he didn't want to. So just put it back together and get it out the door. So thats what I did. Everything was good and the truck ran great cept for one remaining problem. A leak from the rear of the engine. Now I had changed EVERYTHING gasket/oring related in fixing this, and his previous mechanic had done the pan 5 years ago. He pulled his transmission hoping it was rear main, since rear main, cover plate, and oil pan were the only things left to leak. Mind you we already knew his oil pan leaked up front cause you could see bubbles comming from the u shaped part, but I digress.
Yeah yeah I know head questions, I'm geting there, I think the back story is important to know before answering....
Tranny out, I refused to do it on the broken concrete floor in his garage, so he did most of it, which I am glad he did cause he found out how much it sucks working on his dad's cold broken floor, with crappy light and little room to work...I digress again... Soon as the tranny was out I popped under there to do clutch and flywheel and found it was his oil pan, like I had suspected, but had hoped I was wrong. He wanted to just go in and do main seal and hope that was it, hence why HE did the tranny himself, well I assisted a bit.
So at that point it was realized that the engine had to come out, and the next afternoon it was out. Oil pan RTV came off completely stuck to the pan, never bonded to the block, again previous mechanic and his rush to do things. It was obvious where the leaks were thanks to the suggestion he pour in dye before pulling the tranny. So while the engine is out I take a minute to pull valve covers and check some push rods.....
#7 has slight bends to both rods, very minor, but shocking to see (well not entirely as I wanted to pull the heads before) after only 300 miles of driving, OH and I almost forgot, he has a BD exhaust brake, which was disconnected d for the 300 miles right after the injectors were done. So this pretty much clinched it that there is a vlave train issue. So off with the heads, no other push rods showed signs of bending, but i found 3 pistons have made contact with valves, #7 exhaust valve STAMPED its International part number into the piston.
So with this it was decided I'm doing an overhaul to his engine and this brings me to the head questions ect. Got comp 910's and .015 and .030 shims for the heads, and swamps stage 2 .120" wall thickness push rods coming. Going to measure installed height of springs so I can see if there is any problems with the springs being weak or something holding back the valves. Given that no damage is apparent (still some more cleaning to do) I was planning to have the heads tanked and checked at Napa before doing much else.
So questions....
#1. If heads are being hot tanked at Napa, should I remove all valves first, so that all the crap can be cleaned out and seats can be checked?
#2. If heads are being tanked, does that mean I have to replace the brass injector cups again? I am unsure of the cleaners they use and how that would work with the Loctite 620 and the new brass. I am leaning towards yes they will have to be done again..and as such I should just pull them out before having the heads cleaned.
#3. Valve guides? At 263k miles and some piston to head contact, I was thinking valve guides would be in order, especially on those that made contact enough to leave good marks on pistons. If so how does one replace them as I have not found anything on doing it and the ford manuals say nothing except for stem seals. Obviously if there is much play to the valve stem in the guide they need to be done, but how or is that a better left to Napa's machine shop?
#4. New valves? Most of his valves and seats look really good, and he had no compression issues, as far as I could tell. His truck ran good right up till it didn't, and never had starting issues or any appreciable smoke on startup ect. Could start without glow plugs even before the injectors were done, down to about 30 to 40F. My gut says replace valves on cylinders with contact, but small part of me says do them all, but they are pricey. Granted he's balls deep already, and in my mind doing a full head rebuild with all new stuff would be an investment in longevity, even if the block were to ****, the heads could go on a new short block down the road if needed.
#5. Should pistons with contact be changed? Going with my gut I am gonna say no, cause the push rods turned pretzel on the bad cylinders and so far I cannot see any cracks. Kinda thinking that a good part of the other 14 bent push rods were from his excessive use of the exhaust brake (like leaves it on ALL the time, even while not loaded down or towing) but I could be wrong.
Ok I think thats all so far, this would be my first rebuild of diesel heads or a diesel engine. Done tons of gassers, and a load of gas aluminum heads, but never cast iron.
