The first and foremost issue is the way sleeves are installed. The sleeve has either a step or a register and the installer will ultimately take a mallet or a hammer and hit the top of the sleeve to force it all the way down. When looking at sleeves for either a diesel or gas engine, the materials are not necessarily too different. However, there are some things that are important to note if doing sleeve installations on diesel applications versus gas. Less clearance between the piston and cylinder wall make the diameter and roundness of the liner even more critical than before.
Likewise, the liners for these engines have mostly been cast iron, but we are now seeing the use of steel liners. They did that because the manufacturer wanted it to be a serviceable block and the only way you can service them in the field is to have a liner that can be removed by pulling the heads off, swapping pistons, putting new liners back in, reassembling and putting on new gaskets.
However, light-duty diesel blocks, like a 6. Those same motors are being used for weekend truck pulling now. That light-duty diesel market has been really big for us. The diesel side of sleeving will require different piston rings and different bore finishes as well. When it comes to the market for sleeving among engine builders and machine shops, the opportunities are plenty. Advertisement These limits can be seen today when it comes to some 3, horsepower diesel engines having problems with blocks splitting.
The last thing you want in an engine block is material that carries vibration properties to it. Titanium is a really cool option, but we need probably 20 years to figure out how to make it a viable option for our customers. The market and service is entrenched.
As long as there are failures that sleeves can remedy, people will be installing them. Components: Speed of Air Engine Technology. Shop Solutions: Shop Solutions October Magazine Current Issue Past Issues. Connect with us. Advertise Subscribe Contact Us. ICE vs. By Greg Jones. Sleeve installation continues to be a solid market f or engine builders and machine shops. What are Engine Block Sleeves? They can be used when the cylinder becomes: Excessively worn and tapered down Scored Cracked What is resleeving?
This comprehensive guide will help you understand and repair common engine block problems. Contents menu. Expert Advice Head Gasket Failure? Cracked Head or Block? So how much interference do you need? Answers will vary depending on whom you ask. Different sleeve suppliers gave us different recommendations. One said most aluminum blocks typically need about. If the block can accept a flanged sleeve, then you may not need any interference at all.
Another said. Bore distortion is bad because it prevents the hole from being round when you hone it. This prevents good ring sealing and allow blowby and compression losses; neither of which are good for emissions or performance. One supplier said they have changed their thinking about interference fit altogether on some aluminum engine applications.
The sleeves can be installed with minimal interference. A sealer such as Loctite is applied to the bottom third of the cylinder to keep it in place and to prevent oil from migrating up between the bottom end of the sleeve and the block. Anything that gets between the sleeve and block be it oil, carbon deposits or even air can interfere with good heat transfer. With water-cooled cast iron blocks, the general recommendation for installing dry flangless sleeves is to use about.
One tip for make sleeve installation easier while improving heat transfer is to lightly hone the cylinder with grit stones after it has been bored out to accept the sleeve. A smoother finish inside the bore will improve metal-to-metal contact between the sleeve and block when the sleeve is slid into place. On some air-cooled small displacement engines motorcycle and small engines, for example , more interference fit may be required because the cylinders run at higher temperatures.
We have heard of engine builders using as much as. Something else to keep in mind is that if you are sleeving only one damaged cylinder in a block to repair it, the sleeve may distort the adjacent cylinders somewhat — especially if you use a lot of interference fit. The result may be ring sealing problems, compression losses and blowby in the adjacent cylinders.
Using torque plates when boring and honing the block is one way to minimize or correct cylinder bore distortion. In fact, torque plates may be required on many thin wall blocks sleeved or not to achieve a really good bore finish that is round and straight. Install the torque plate and head gasket on the block, and then tighten the head bolts to specifications before honing. Measuring Interference To accurately determine the amount of interference, you need two dimensions: the average outside diameter OD of the sleeves, and the average inside diameter ID of the bores in the block.
To measure these dimensions you need an accurate OD micrometer and ID micrometer or bore gauge. Measure the sleeve at the top, middle and bottom. Write down the numbers.
Then rotate the sleeve 90 degrees and measure again. Average together all of these numbers to calculate the average OD of the sleeve. Next, do the same thing for the bore. Measure the top, middle and bottom, then rotate your bore gauge or ID mike 90 degrees and repeat.
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