How can you tell if your glow plugs have failed or are failing? If your diesel starts hard when cold, or starts but runs rough for 30 to 60 seconds before smoothing out, or the glow dash light flashes right after startup, then it may be time to replace the glow plugs. We recommend they should be replaced in sets unless you have the odd failure of just one fairly new plug. This is especially true on the 603 engine which requires removal of the intake manifold to replace the plugs. You don't want to have to do the job again right away!
Monark glow plugs are actually one of the last quality glow plugs still made in Germany. Even Bosch now makes their glow plugs in France, Turkey and other locations in Europe. Now don't get me wrong - Bosch is still a good product. But these Monark glow plugs are superb. Even comes with 6 new high quality locking nuts for the wires. (which Bosch does not supply!)
SVO WVO: If you are running SVO WVO fuel we have found that glow plugs may not last as long compared to running diesel fuel. The tips and chambers tend to coke up faster. Super important that you ream your glow plug chambers more often. These Monark plugs concentrate the heat more toward the tip and which keeps the glow plug ends cleaner.
IF you are not familiar with replacing the glow plugs on these models, we currently offer a manual on this procedure. look below to view this manual. Please note that you will also need to replace the intake manifold gasket when changing the glow plugs. Look below to view the required gasket. Reaming the glow plug holes is a must to prevent long glow plug life. Just type "glow plug reamer" in the search box.
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