More spark plug questions

[mattp33]

Hey guys I am changing the spark plugs on my 89 merc 90hp. I went to the marina and they gave me NGK BUHW-2, when I took the covers off it has BU8H plugs in it? Did the guy before me use the wrong plug? It runs fine now so should I replace the plugs with the same or should I be using the ones the marina says it calls for?

 

Thanks

[DRIFTER_016]

Hey guys I am changing the spark plugs on my 89 merc 90hp. I went to the marina and they gave me NGK BUHW-2, when I took the covers off it has BU8H plugs in it? Did the guy before me use the wrong plug? It runs fine now so should I replace the plugs with the same or should I be using the ones the marina says it calls for?

 

Thanks

 

 

Use the ones the marina sold you the BU8H's are incorrect for that engine.

 

Check your serial# against this Chart

 

This Chart shows the engines that the BU8H plugs are recomended for.

[mattp33]

what if my serial number is A728264?

[DRIFTER_016]

what if my serial number is A728264?

 

 

Click the check mark that coresponds to your engines year Here

 

i.e. the check mark on the first row of the chart.

[mattp33]

NGK site says I should be using BUHW-2 but now I am not sure cause of that chart? My serial number is not on there. What the heck engine do I have?

[mattp33]

ya I was just there lol. I got the right ones I know I do. I wonder why this is why its hard to start sometimes, the guy has the wrong plug in it!

[DRIFTER_016]

ya I was just there lol. I got the right ones I know I do. I wonder why this is why its hard to start sometimes, the guy has the wrong plug in it!

 

 

I have a '91 and they are not the easiest staring engines around to begin with.

I have found that the beast way to start mine when cold is to pump the fast idle lever a couple of times and leave it all the way up then push in the key (primer) and spin the starter, push in the key again while turing over. It will usually catch at this point, if not pump the fat idle lever a couple more times and push in the key and turn over again. Once the engine catches you will need to push in the key a couple more times (when the engine starts to stumble and the rpm starts to drop). Could be 2 or 3 times (depends on how fast the engine warms up). Once it runs on it's own drop the fast idle lever to a reasonable rpm to finish warming up.

 

Can't wait to get a nice fuel injected 4 stroke for my boat.