86 f250 6.9 rebuild/refresh advice and questions

stealth13777

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I have a 1986 F250 6.9 with a banks turbo that, when i repaired the turbo and got it working again (ron), promptly decided to blow a head bolt and thus the head gaskets. Shut it off immediately when temps started to rise, so no known damage. The heads are currently at a machine shop undergoing testing. Will be using ARP head studs in the reassembly.

While they were out, I spent some time looking at the engine (unknown mileage total; could be 145,000, could be 245,000, etc.). It seems at this point in the process, I would be stupid not to at least do rings and bearings. I have already invested in new water pump, heater core, radiator, oil cooler seals, clutch, and more. Now the heads and injectors are being gone over. Oil pan could use a new seal anyway to fully stop the leaking, so the motor is coming out. I have no plans to do anything further to the truck performance wise (other than the banks kit it already has), but rather want to use it as a personal 'around the house' work vehicle and tow platform around town, hopefully well into the future after all this time and money invested. Body is excellent if I can get the mechanical stuff all fixed.

So my question is, what rings and bearings are best? What else should I be looking at, checking, measuring, etc.? All pistons look good, motor ran well with good oil pressure, and I know to hone the cylinders if I put new rings in. My expertise ends at changing the heads, so this is new territory for me. Thankfully I have an experienced tech at the shop where I'm working (diy shop) who offered to lend a hand. Advice on brands, specifics, advice as far as execution of the rebuild; anything and everything is appreciated! I need all the help I can get, and will continue to search this and other forums for more info. My last question is; how far is reasonable to go with the refresh? If the engine was good before, are rings and bearings a good refresh without going further than necessary, such as camshaft, etc.? The goal is a well running engine that I can expect to last.

I am at the point where I want to do everything right and ensure I have a motor that will be good after this work, but budget is a factor. I know I could just throw the heads back on, but with unknown mileage, and most of the work already done... I can provide pics of anything necessary.
 

icanfixall

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Welcome to the forum. Do not use a cork or rubber gasket on the oil pan. These engines never had a gasket there. The factory used an RTV and it works great. I used Permatex ultra copper plus and no leaks. I have used this for many years on all my engine rebuilds and never a leak. Other members like other RTV materials too.Just ask here. The international factory used Mahle pistons and rings so I personally would use them again.
 

stealth13777

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Interesting, so the RTV actually works better? I would like to keep the current pistons but will definitely look at Mahle rings; should match the originals


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icanfixall

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Our engines have 2 different size rings so be careful what you might order.
 

oregon96psd

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Before you go tearing it apart measure cylinder bore size, taper, out of round,(as best you can with the pistons still in it, most wear happens at the top anyway) check for a ridge at the top of the cylinder and scoring. When you get the oil pan off to re-seal pull a rod and main bearing and check them to see if their worn into the backing. It might all check out good and be useable, why throw money into a hole under the hood if you don't have to?
 

stealth13777

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Before you go tearing it apart measure cylinder bore size, taper, out of round,(as best you can with the pistons still in it, most wear happens at the top anyway) check for a ridge at the top of the cylinder and scoring. When you get the oil pan off to re-seal pull a rod and main bearing and check them to see if their worn into the backing. It might all check out good and be useable, why throw money into a hole under the hood if you don't have to?

All sounds good. Appreciate the specifics on measurements to take, and I will be sure to check them all. I figured even if it checks out bearings and rings wouldn't be a bad idea knowing they have at least 145k on them and more likely 245k. Wrong in that assumption? Is it a total waste to do the bearings if they aren't worn out yet, seeing as how I will be pulling the pistons for rings anyway? Kinda figure rings are a given at its age and mileage. I guess which bearings to focus on is a good question as well. Crank, rods, cam bearings? Or some but not others?

I also talked to my machine shop here. As I have never done bearings or rings, and in the event of any other work needed, they did the courtesy of pricing out each individual possibility if they were to do some of the work, from decking the block to simply reassembling short and long. They are willing to take over at any point in the process if asked, and give it back to me with as much work left as I feel I can do. Basically they will do whatever I am not comfortable doing myself. One thing they mentioned (and it was not expensive) was installing cam bearings. Is this something I should be looking at as well, or leave the cam alone? All of their prices are very reasonable and they are very well respected, so I want to do all measurements and check everything out to ensure the engine ends up solid, while of course not wasting money I don't have. (For example, boring and honing the block is $100).



Pics of progress so far, and of the truck. I have changed the john deer tag to atlanta braves. Not that it matters when it isn't running.

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stealth13777

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Pics of the cylinders and bores. This is as far as I have gotten, with the heads in the machine shop as of today. Figure it would help the budget to know head condition before going further. No cleaning has been done yet. The bores look worse in the pictures than they are; the ones i can see are smooth with no gouges, just the discoloration as pictured. If they measure well, I'm hoping a hone is all that is needed.
 

oregon96psd

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This is my opinion, and free advice is worth what you pay for it but....you seem to be putting the cart before the horse here. If it were my engine, I would measure and check things out first before just going ahead and deciding to re ring it. Unless your completely set on it for piece of mind, and theres nothing wrong with that btw, but its a lot better to have some facts before ordering parts. How long did you run it before it blew the gasket, long enough to get an idea of how much oil it burned, if so how much? A lot of blowby? For what you said you want to use it for, it doesnt sound like it'll get a whole lot of miles so maybe a rebuilt engine isnt necassary? When i did mine i pulled the heads, checked the bores, pulled the lifters, all looked good there, so i had the heads milled and seats ground, bought new valves, springs, seals and rocker arms. I lapped the valves and put it back together....I personally didnt see any reason to dump a ton of money into a 30 year old idi that ran fine except for a weeping headgasket. I guess it just depends on if you want to go through it just to know its been done, or if you get into it and find it NEEDS to be done.

Oh ya, your pics dont work.
 
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stealth13777

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I'll try the pics on another computer. Work fine on mine and my friend's computer. May try a different upload. Thanks for the heads up.

As far as the head you went further than I was planning. All looked ok up there so the shop will check the valves and def look at new seals, but I was going to just clean the crud off the springs, rocker arms, and pushrods, reoil, and put it back together. I'll stick with this plan unless there's a failure prone part up there I should be taking a closer look at. Any specific reason you did yours?

Didn't run for long enough to get a good idea, bout 150 miles, but like you said, with all this work already done and rings relatively inexpensive, I'm pretty set on those for peace of mind. I know it was burning some oil but could have been from the valves or rings. Wish I had done a compression test. The rest I will measure when I get time and talk over the expense with the girl. I'm a big preventive maintenance guy and hate waiting for things to break, but budget conscious about it. Some things you should be preventive about and some aren't worth it, I totally agree. Might be a little while until I get time to pull it out and take a look.
 

oregon96psd

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I'll stick with this plan unless there's a failure prone part up there I should be taking a closer look at. Any specific reason you did yours?

.


The 6.9l rocker arm is a pos design that wears the aluminum pivot point, so I replaced them with the 7.3l style...bolt in swap. All but three of my exhaust valves were pitted on the end of the valve stem, possibly from the rocker arms, not sure on that, but because I was replacing the exhaust valves I went ahead and did intakes too.
 

tbiagent69

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Can you explain the difference between the 6.9 and 7.3 valvetrains? Is there a pic or article? I've got 130k miles on mine, is there a time frame they should be looked in to?
 

stealth13777

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http://www.ford-trucks.com/forums/1271747-lifter-r-and-r-6-9-a-2.html

Page two there is a picture that you can see the two designs. As far as time, couldnt tell ya, mine were junk when i did my headstuds so i just threw them in the scrap iron pile as i pulled them out.

Any tips on where to get the valvetrain parts? I'm going to ask the machine shop if they will look at them (since trying to identify what needs to be replaced on parts I have never had any experience with seems like a crapshoot; I can turn a wrench and diagnose stuff I've been taught, but never done engine internals; thats why I appreciate all the help!)

Pics reposted. Work this time! In the last pic you can see the gunk on the rockers and the top part of the pushrods (it does not continue down into the part that was in the block. Any thoughts? I can get a lot more pics up of the process as I work through it (and I have more of what I have already done) if it helps anybody or if it helps y'all answer my questions.

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oregon96psd

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Those are the old style rocker, throw them as far away from the truck as you can.....


On a side note, how wide are the tires on it? Mines about due for a set and I like the way yours looks with the fairly short but wide tires.
 

stealth13777

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Those are the old style rocker, throw them as far away from the truck as you can.....


On a side note, how wide are the tires on it? Mines about due for a set and I like the way yours looks with the fairly short but wide tires.

Will need to find a good deal on new ones then. Those things aren't cheap on summit when you consider there are 8. Might look at pushrods too since they are worn to the old one. Stuff keeps adding up. *Edit Even rockauto wants $41 for EACH pair. We are talking $330 just for that. You're saying to be safe that whole thing should be replaced (since being safe with the engine is what I'm doing). Ugh. Those aren't as hard to get to... just valve covers, don't have to pull the engine or heads. Will have to research more. Is it catastrophic if one fails?

And I'll try to remember to take a look at the tires tomorrow see what exact size they are. Those are a firestone product the truck came with (except one BFG), and when I looked them up to replace the BFG and one thats dry rotting they are pretty cheap for truck tires, nice tread pattern, and ride pretty well imo.
 
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