Sleeved blocks risky?

[Dave7.3]

Hey guys,
I really love my truck, but I recently came across a good deal for a 1994 F250 factory turbo IDI. ZF5, 4x4 extended cab XLT. Just the kind of truck/body style I like!

I have weighed the pros and cons but can only narrow it down to one thing that I am uncertain of...

At 130k, the engine was rebuilt due to cavitation. The 7.3L cylinders were bored/sleeved and new parts installed throughout (including injection system).
Now, after all the horror stories I have heard about sleeved blocks...is it worth the risk? So far the rebuilt engine only has 12k on the clock.

I have yet to go see this truck in person, but if the risk is just too high with sleeved blocks (no idea who did the machine work) is it worth the time?

Let me know what you think,
-Dave

 

[oldmisterbill]

I have a sleeved engine now (my second one) as long as thay are done right ,no problem.

 

[87crewdually]

The problem will come from improper tolerence in the bore during the machining process. If a retaining lip isn't machined or not a tight enough fit, the sleeve can slip down the bore colliding with the crank and the connecting rod. Not good and really once assembled no way to tell.
At your stage of the game it would be a game of chance.

 

[sassyrel]

Hey guys,
I really love my truck, but I recently came across a good deal for a 1994 F250 factory turbo IDI. ZF5, 4x4 extended cab XLT. Just the kind of truck/body style I like!

I have weighed the pros and cons but can only narrow it down to one thing that I am uncertain of...

At 130k, the engine was rebuilt due to cavitation. The 7.3L cylinders were bored/sleeved and new parts installed throughout (including injection system).
Now, after all the horror stories I have heard about sleeved blocks...is it worth the risk? So far the rebuilt engine only has 12k on the clock.

I have yet to go see this truck in person, but if the risk is just too high with sleeved blocks (no idea who did the machine work) is it worth the time?

Let me know what you think,
-Dave

sleeved engines are great--I F , you have a quality machinist!!!!!!!!!! retaining lip on bottom,and the head gasket and head hold the top--and plenty of red loctite!!!!!!!

 

[94turboidi]

I always thought about if I rebuilt my engine seeing if it could be sleeved down to a 6.9 bore size and run 6.9 pistons. I think it would be a far better setup than the 6.9 or 7.3 the way they are from the factory. I bet cavitation wouldn't be near the issue either. But......my engine seems to be in really good shape and will probably last for years until a cummins goes in there.

 

[icanfixall]

All the above postings are true. The best sleeve is one that has a lip on the top that gets set into a wider machined step in the block. This kind of sleeve cannot slip in the bore because its held in place by the head. The bottom step is not a important then but it should be there. These are much more difficult to install because you need both the top and bottom fits to reach there limits and seat down firmly. I feel the top step is the most important fit and the bottom could be machined 1 or 2 thousands short so the top is completely in the step. Soaking the sleeves in liquid nitrogen to shrink fit them is the way to go. Some machine shops use dry ice and some use a freezer which really can't shrink the sleeve enough for an easy press fit.. If you knew who did the macine work then your choice is easier. Seems like this engine has run ok so far. The only way to know whats been done and if its been don't right is to completely tear down the engine... Thats really asking alot but at least you would know... Try to find out what shop did the work is possible...

 

[bike-maker]

Back in my machining days I installed quite a few sleeves. I've seen a few slip in motors built by others, and hey all happened after only a couple of heat cycles; way before having 12k on the clock. All of the above is true. As long as the machinist left a good lip on the bottom the sleeve won't go anywhere. The better option is the sleeves with the lip around the top. These are definitely better, but take twice as much labor to install correctly. Most machine shops opt for the ones without the lip for this reason. As for installation, we used to leave the sleeve in the freezer for a couple of days, heat the block up with a rosebud tip on the torch, and beat 'em in with a 10 lb. sledgehammer. We usually machined them to about .002" interference fit, IIRC.

 

[Rot Box]

Were all the cylinders sleeved? This is my situation as I bought a truck with a sleeved block and don't know who preformed the work:

Supposedly my block was sleeved on two cylinders according to the po. Who's to say the other 6 aren't about ready to blow out? I feel like I'm on borrowed time every time I drive my truck but I don't feel too bad because I have a new 6.9 ready to take the 7.3's place. Finding a replacement motor for a decent price isn't too bad for these trucks--now if it was a Cummins or a PSD the cost goes through the roof!

If its the truck you want buy it, drive it and if you do have problems be ready for it. Keep a weekly (or more often) eye on your coolant and oil and that's about all you can do. Again no problem with sleeves as long as they were installed right, but unless you were there to watch and knew what to look for its anyone's guess...

 

[Knuckledragger]

Rebuilding one of these engines is not a huge investment compared to a cummins or buying a new truck. The fact that this engine has gone 12,000 miles on sleeves is a testament to the quality of the work, no matter what type of sleeve was used. Bike-maker was right, if something is going to go wrong, it will do so very soon after the first start up.

If you are nervous just thinking about it, don't buy. If the price is right, pick up a good deal on a truck that will give a lot of service without complaint. And don't worry about having to work on it later, that is why this forum exists.

 

[icanfixall]

These blocks had 2 cylinders that were usually problematic for cavitation. So some were only sleeved on those problem cylinders... They had issues when the blocks were cast due to sand drifts. So if only a special two cylinders were done it may be fine... not all cylinders have the cavitation issues. I had all 8 sleeved but I do go overboard for my piece of mind. When my next block is sleeved it will be the flanged top sleeves or nothing. I have heard of 7.3 blocks being sleeved and then bored to 6.9 but have never actually seen one so don't know for sure if its been done... that would be a great high boost turbo engine that would never have cavitation issues. And with 1/2 inch studs it wont lift a head boosting high numbers....

 

[Dave7.3]

Thanks for all the replies guys! Many of you share my same thoughts on this matter...I knew this was the place to ask.

When I talk to the guy, I will have to ask a little more directly who did the machine work. He did mention one of the local big truck shops called Rapid Diesel did the injection system work on the engine and checked it over. Not sure if he had them do the machine work too, but it would be a huge plus if they did. I know their work and they seem to be a great shop. Otherwise, it is indeed a costly gamble.

I am also not sure which cylinders were sleeved, another question to ask. I will keep you guys posted when I go to check it out in person this weekend.

EDIT: Almost forgot...the guy mentioned something about the shop he went to machining the heads and it starts better somehow? Not exactly sure what that entails...

 

[towtruckdave]

If that block was fixed poorly, it probably would have failed already.

You are better off with the sleeves than a mystery block, IMHO.

 

[Diesel JD]

Machining the heads so it starts better? Maybe they were decked a little bit which gives higher compression and it doesn't even take much. My truck was 450 even all the way around before I did head gaskets and then after I had about .005" taken off the heads some cyls were as high as 525 and others as low as 450. This has probably accounted for the slightly rougher idle since then. I'd suspect like the other more qualified guys that a dry sleeved block with 12K miles on it probably would have failed much sooner if it was going to. We've seen dry sleeves fail here but usually it was soon after the rebuild. I wouldn't be afraid of that block. I think #8 was the most likely cylinder to cavitate, followed by...I can't remember which was the next most likely, but someone here will.

 

[typ4]

I also have 2 holes sleeved, I have rebuilt several and done all 8, you would know if it was wrong. Never use loctite, if someone says that themachine work isnt right.I worked for a guy like that.

As for the heads most likely the valvejob had more to do with the good starting than decking the heads, 5 thou wont change much. Also the head gaskets might be thinner than factory.

ask the owner if he has towed with it , if so buy it. its been plenty hot.

 

[Dave7.3]

I would like to personally thank everyone for their expertise. I'm feeling more confident in this purchase now but the ultimate decision will come after seeing it.

As far as I know, it has been ran and worked pulling a 5th wheel camper since the rebuild. I guess you guys are right, If it didn't fail from that then it should be solid. Thankfully after the owner's cavitation experience, he has watched the SCA's like a watchdog he tells me. Taking some test strips anyway though. You never know!