maybe the engine gets to hot. This causes the spark to disperse faster than it would in a cooler engine . this maks the spark plug work more than nessesary and were it out quicker. It could also be that you are using a sparkplug not made for that type of engine.
A short circuit somewhere.
i replaced the head unit and the fuse stoped blowing.
not usually!!if fuse is blowing out check for short!!
Find out why the fuse is blowing. You have a short or the circuit is overloaded.
Obviously, if any fuse keeps blowing there is a serious fault in that circuit.Take it somewhere they can fix it.
Your dryer fuse may keep blowing due to a variety of reasons, such as a clogged vent, overheating, or a faulty heating element. It is important to check these components and address any issues to prevent the fuse from blowing repeatedly.
It is very common for the starter to be the cause of that fuse blowing.
Wrong amp of fuse
A short.
There is a short. Shorts blow fuses. The motor may be bad - or need lubrication or a short on the wring leaving the fuse box to where ever it goes. Unplug the more and try a new fuse!
You have a problem with the electrical circuit.
A over current condition in that circuit.