diff --git a/t/pt-archiver/bulk_insert.t b/t/pt-archiver/bulk_insert.t
index ae66dde6..f3aa8ba3 100644
--- a/t/pt-archiver/bulk_insert.t
+++ b/t/pt-archiver/bulk_insert.t
@@ -103,9 +103,13 @@ for my $char ( "\N{KATAKANA LETTER NI}", "\N{U+DF}" ) {
    my $sql = qq{INSERT INTO `bug_1127450`.`original` VALUES (1, ?)};
    $utf8_dbh->prepare($sql)->execute($char);
 
+# We need to have --no-check-charset here, because utf8 that we use in the test file
+# is alias of utf8mb3 in 5.7 and alias of utf8mb4 in 8.0.
+# We cannot set this character set explicitly due to Perl limitations.
+# Changing utf8 to utf8mb4 will break test on 5.7
    $output = output(
       sub { pt_archiver::main(qw(--no-ascend --limit 50 --bulk-insert),
-         qw(--bulk-delete --where 1=1 --statistics --charset utf8),
+         qw(--bulk-delete --where 1=1 --statistics --charset utf8 --no-check-charset),
          '--source', "L=1,D=bug_1127450,t=original,F=$cnf",
          '--dest',   "t=copy") }, stderr => 1
    );
diff --git a/t/pt-archiver/issue_1225.t b/t/pt-archiver/issue_1225.t
index 2c99fc23..2498b448 100644
--- a/t/pt-archiver/issue_1225.t
+++ b/t/pt-archiver/issue_1225.t
@@ -23,11 +23,15 @@ my $dbh = $sb->get_dbh_for('master');
 if ( !$dbh ) {
    plan skip_all => 'Cannot connect to sandbox master';
 }
+elsif ($sandbox_version gt '5.7') {
+   plan tests => 4;
+}
 else {
    plan tests => 5;
 }
 
 my $output;
+my $archived_rows;
 
 # #############################################################################
 # Issue 1152: mk-archiver columns option resulting in null archived table data
@@ -57,7 +61,6 @@ SKIP: {
       "--check-charset"
    );
 
-}
 $output = output(
    sub { pt_archiver::main(
       '--source',  'h=127.1,P=12345,D=issue_1225,t=t,u=msandbox,p=msandbox',
@@ -66,12 +69,13 @@ $output = output(
    },
 );
 
-my $archived_rows = $dbh->selectall_arrayref('select c from issue_1225.a limit 2');
+$archived_rows = $dbh->selectall_arrayref('select c from issue_1225.a limit 2');
 
 ok(
    $original_rows->[0]->[0] ne $archived_rows->[0]->[0],
    "UTF8 characters lost when cxn isn't also UTF8"
 );
+}
 
 $sb->load_file('master', 't/pt-archiver/samples/issue_1225.sql');
 
@@ -79,7 +83,7 @@ $output = output(
    sub { pt_archiver::main(
       '--source',  'h=127.1,P=12345,D=issue_1225,t=t,u=msandbox,p=msandbox',
       '--dest',    't=a',
-      qw(--where 1=1 --purge -A utf8)) # -A utf8 makes it work
+      qw(--no-check-charset --where 1=1 --purge -A utf8)) # -A utf8 makes it work
    },
 );
 
diff --git a/t/pt-archiver/issue_1229.t b/t/pt-archiver/issue_1229.t
index 9a0f01a6..0946b687 100644
--- a/t/pt-archiver/issue_1229.t
+++ b/t/pt-archiver/issue_1229.t
@@ -33,7 +33,7 @@ elsif ( $DBD::mysql::VERSION lt '4' ) {
 my $output;
 my $rows;
 my $cnf  = "/tmp/12345/my.sandbox.cnf";
-my $file = "/tmp/mk-archiver-file.txt";
+my $file = "/tmp/pt-archiver-file.txt";
 
 # #############################################################################
 # Issue 1229: mk-archiver not creating UTF8 compatible file handles for
@@ -53,11 +53,15 @@ is_deeply(
 
 diag(`rm -rf $file >/dev/null`);
 
+# We need to have --no-check-charset here, because utf8 that we use in the test file
+# is alias of utf8mb3 in 5.7 and alias of utf8mb4 in 8.0.
+# We cannot set this character set explicitly due to Perl limitations.
+# Changing utf8 to utf8mb4 will break test on 5.7
 $output = output(
    sub { pt_archiver::main(
       '--source',  'h=127.1,P=12345,D=issue_1225,t=t,u=msandbox,p=msandbox',
       '--file',    $file,
-      qw(--where 1=1 -A UTF8)) # -A utf8 makes it work
+      qw(--no-check-charset --where 1=1 -A UTF8)) # -A utf8 makes it work
    },
    stderr => 1,
 );
diff --git a/t/pt-archiver/pt-1898.t b/t/pt-archiver/pt-1898.t
deleted file mode 100644
index bdf9b8f0..00000000
--- a/t/pt-archiver/pt-1898.t
+++ /dev/null
@@ -1,109 +0,0 @@
-#!/usr/bin/env perl
-
-BEGIN {
-   die "The PERCONA_TOOLKIT_BRANCH environment variable is not set.\n"
-      unless $ENV{PERCONA_TOOLKIT_BRANCH} && -d $ENV{PERCONA_TOOLKIT_BRANCH};
-   unshift @INC, "$ENV{PERCONA_TOOLKIT_BRANCH}/lib";
-};
-
-use strict;
-use warnings FATAL => 'all';
-use threads;
-
-use English qw(-no_match_vars);
-use Test::More;
-
-use Data::Dumper;
-use PerconaTest;
-use Sandbox;
-use SqlModes;
-use File::Temp qw/ tempdir tempfile /;
-
-if ($ENV{PERCONA_SLOW_BOX}) {
-    plan skip_all => 'This test needs a fast machine';
-} else {
-    plan tests => 6;
-    #plan skip_all => 'This test is taking too much time even in fast machines';
-}                                  
-
-our $delay = 15;
-
-my $tmp_file = File::Temp->new();
-my $tmp_file_name = $tmp_file->filename;
-unlink $tmp_file_name;
-
-require "$trunk/bin/pt-archiver";
-
-my $dp = new DSNParser(opts=>$dsn_opts);
-my $sb = new Sandbox(basedir => '/tmp', DSNParser => $dp);
-my $master_dbh = $sb->get_dbh_for('master');
-my $slave_dbh = $sb->get_dbh_for('slave1');
-my $master_dsn = 'h=127.0.0.1,P=12345,u=msandbox,p=msandbox';
-my $slave_dsn = 'h=127.0.0.1,P=12346,u=msandbox,p=msandbox';
-
-sub reset_query_cache {
-    my @dbhs = @_;
-    return if ($sandbox_version >= '8.0');
-    foreach my $dbh (@dbhs) {
-        $dbh->do('RESET QUERY CACHE');
-    }
-}
-
-# 1) Set the slave delay to 0 just in case we are re-running the tests without restarting the sandbox.
-# 2) Load sample data
-# 3) Set the slave delay to 30 seconds to be able to see the 'waiting' message.
-diag("Setting slave delay to 0 seconds");
-$slave_dbh->do('STOP SLAVE');
-$slave_dbh->do('RESET SLAVE');
-$slave_dbh->do('START SLAVE');
-
-diag('Loading test data');
-$sb->load_file('master', "t/pt-online-schema-change/samples/pt-1898.sql");
-
-my $num_rows = 5000;
-diag("Loading $num_rows into the table. This might take some time.");
-diag(`util/mysql_random_data_load --host=127.0.0.1 --port=12345 --user=msandbox --password=msandbox test pt178 $num_rows`);
-
-diag("Setting slave delay to $delay seconds");
-
-$slave_dbh->do('STOP SLAVE');
-$slave_dbh->do("CHANGE MASTER TO MASTER_DELAY=$delay");
-$slave_dbh->do('START SLAVE');
-
-# Run a full table scan query to ensure the slave is behind the master
-# There is no query cache in MySQL 8.0+
-reset_query_cache($master_dbh, $master_dbh);
-$master_dbh->do('UPDATE `test`.`joinit` SET g = g + 1 WHERE g <> 0');
-
-# This is the base test, ust to ensure that without using --check-slave-lag nor --skip-check-slave-lag
-# pt-online-schema-change will wait on the slave at port 12346
-
-my $max_lag = $delay / 2;
-my @args = ("--source",  "$master_dsn,D=test,t=joinit", "--purge", "--where", "'g < 45'",
-           "--commit-each", "--limit", "500", "--statistics", "--check-slave-lag", "h=127.0.0.1,P=12346,u=msandbox,p=msandbox",
-           "--max-lag", "1");
-diag("Starting base test. This is going to take some time due to the delay in the slave");
-diag("pid: $tmp_file_name");
-my $argstr = join(@args, " ");
-my $output = `$trunk/bin/pt-online-schema-change $argstr 2>&1`;
-
-like(
-      $output,
-      qr/Replica lag is \d+ seconds on .*  Waiting/s,
-      "Base test waits on the correct slave",
-);
-
-
-diag("Setting slave delay to 0 seconds");
-$slave_dbh->do('STOP SLAVE');
-$slave_dbh->do('RESET SLAVE');
-$slave_dbh->do('START SLAVE');
-
-$master_dbh->do("DROP DATABASE IF EXISTS test");
-
-# #############################################################################
-# Done.
-# #############################################################################
-$sb->wipe_clean($master_dbh);
-ok($sb->ok(), "Sandbox servers") or BAIL_OUT(__FILE__ . " broke the sandbox");
-done_testing;
diff --git a/t/pt-online-schema-change/samples/pt-1898.sql b/t/pt-online-schema-change/samples/pt-1898.sql
deleted file mode 100644
index 3f7be4de..00000000
--- a/t/pt-online-schema-change/samples/pt-1898.sql
+++ /dev/null
@@ -1,36 +0,0 @@
--- give master some advantage on performance
-SET GLOBAL innodb_flush_log_at_trx_commit=2;
-SET GLOBAL sync_binlog=1000000;
-SET GLOBAL innodb_buffer_pool_size=2*1024*1024*1024;
-
-DROP DATABASE IF EXISTS test;
-CREATE DATABASE test;.
-USE test;
- 
-DROP TABLE IF EXISTS `joinit`;
- 
-CREATE TABLE `joinit` (
- `i` int(11) NOT NULL AUTO_INCREMENT,
- `s` varchar(64) DEFAULT NULL,
- `t` time NOT NULL,
- `g` int(11) NOT NULL,
- PRIMARY KEY (`i`),
- KEY g_idx (g)
-) ENGINE=InnoDB DEFAULT CHARSET=latin1;
-
-INSERT INTO joinit VALUES (NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )));
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; -- +256 rows
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; -- +512 rows
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; -- +1024 rows
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; 
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; 
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit; 
-INSERT INTO joinit SELECT NULL, uuid(), time(now()), (FLOOR( 1 + RAND( ) *60 )) FROM joinit;