diff --git a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/ClasspathTests.java b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/ClasspathTests.java
index 95978e6c76d..e38ed1a52c0 100644
--- a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/ClasspathTests.java
+++ b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/ClasspathTests.java
@@ -5782,6 +5782,13 @@ public void testUnknownElements1() throws CoreException {
 		classpath[1] = src1;
 		project.setRawClasspath(classpath, null);
 
+		try {
+			Thread.sleep(500);
+		} catch (InterruptedException e) {
+			e.printStackTrace();
+		}
+		waitForManualRefresh();
+
 		// check that .classpath has correct content
 		String contents = new String (org.eclipse.jdt.internal.core.util.Util.getResourceContentsAsCharArray(getFile("/P/.classpath")));
 		assertSourceEquals(
diff --git a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/JavaProjectTests.java b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/JavaProjectTests.java
index c55f03736f6..b4f12d4311e 100644
--- a/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/JavaProjectTests.java
+++ b/org.eclipse.jdt.core.tests.model/src/org/eclipse/jdt/core/tests/model/JavaProjectTests.java
@@ -2486,8 +2486,12 @@ public void run(IProgressMonitor monitor) throws CoreException {
 				}
 			},
 			null);
+		try {
+			Thread.sleep(500);
+		} catch (InterruptedException e) {
+			e.printStackTrace();
+		}
 		waitForManualRefresh();
-		waitForAutoBuild();
 		IPackageFragmentRoot root = getPackageFragmentRoot("P", "");
 		assertElementsEqual(
 			"Unexpected children size in 'P' default source folder",