wi4x4man
Seaman
- Joined
- Aug 25, 2010
- Messages
- 55
Okay...
So I left a thread on here about a week ago where I was out on the lake and my new (reman) 4.3L Mercruiser engine up and died on me. I figured that I fouled the plugs up, and they were pretty dirty with carbon as I had spent a while idling. I went ahead and cleaned them. However it "sounded" like I lost compression when it would crank (same sound it made when I first set the valves and two cylinders didn't have good compression). Long story short, my attempts to start it ended up causing me to flood the crap out of the engine. My thought was that the fuel washed everything down and that caused me to loose some compression.
So, this evening I went through and checked compression. I had good compression on all cylinders (130-160 psi) except for one which was at about 40 psi. I shot some oil down the hole and the compression came up to about 75 psi. Okay, fine... Not the greatest, but it was better. (Keep in mind I had 160 psi when I set the engine up 20 hours ago)
I figured I would see how my spark was (as it was getting dark) and so I grabbed a plug, put it to a bolt on the side of the block, and it was an orange color. WTF? I know that blue is best, but what the heck is the deal with orange? One other plug wouldn't even spark across the gap, it skirted around to the inside of the plug.
I have new wires, a new rotor, and a new cap. The plugs were new when I put everything together. The only thing that is old is the coil and the ignition box. The engine is a 1990 Mercruiser (pre-balance shaft with the Thunderbolt IV setup). Everything on it is mercruiser brand. I did this thing by the book and I am having issues.
So, what the heck does an orange spark tell me? I am going to purchase new plugs again tomorrow, but what is the deal with the orange? Is my coil bad? Are my wires shot? It is orange no matter what wire I use.
I am a diesel guy. I know diesel engines inside and out. When I first repowered my boat, I was thinking of putting a 4045TFM75 John Deere diesel in it, but decided against it... I thought I would have too many problems with fitup, torsional vibration, and etc. But at least with a diesel engine, you don't have to worry about stupid freaking spark plugs and the other BS that goes along with them.
The only marine gas engine that is worth anything in my mind is the old 165 Mercruiser straight six. I have one of those that is 35 years old and runs like a raped ape. No matter what, that thing fires every time, has excellent get up and go, and what is really nice, is VERY EASY TO WORK ON!
As you can tell, I am frustrated as all get out. I think it is time for a beer.
So I left a thread on here about a week ago where I was out on the lake and my new (reman) 4.3L Mercruiser engine up and died on me. I figured that I fouled the plugs up, and they were pretty dirty with carbon as I had spent a while idling. I went ahead and cleaned them. However it "sounded" like I lost compression when it would crank (same sound it made when I first set the valves and two cylinders didn't have good compression). Long story short, my attempts to start it ended up causing me to flood the crap out of the engine. My thought was that the fuel washed everything down and that caused me to loose some compression.
So, this evening I went through and checked compression. I had good compression on all cylinders (130-160 psi) except for one which was at about 40 psi. I shot some oil down the hole and the compression came up to about 75 psi. Okay, fine... Not the greatest, but it was better. (Keep in mind I had 160 psi when I set the engine up 20 hours ago)
I figured I would see how my spark was (as it was getting dark) and so I grabbed a plug, put it to a bolt on the side of the block, and it was an orange color. WTF? I know that blue is best, but what the heck is the deal with orange? One other plug wouldn't even spark across the gap, it skirted around to the inside of the plug.
I have new wires, a new rotor, and a new cap. The plugs were new when I put everything together. The only thing that is old is the coil and the ignition box. The engine is a 1990 Mercruiser (pre-balance shaft with the Thunderbolt IV setup). Everything on it is mercruiser brand. I did this thing by the book and I am having issues.
So, what the heck does an orange spark tell me? I am going to purchase new plugs again tomorrow, but what is the deal with the orange? Is my coil bad? Are my wires shot? It is orange no matter what wire I use.
I am a diesel guy. I know diesel engines inside and out. When I first repowered my boat, I was thinking of putting a 4045TFM75 John Deere diesel in it, but decided against it... I thought I would have too many problems with fitup, torsional vibration, and etc. But at least with a diesel engine, you don't have to worry about stupid freaking spark plugs and the other BS that goes along with them.
The only marine gas engine that is worth anything in my mind is the old 165 Mercruiser straight six. I have one of those that is 35 years old and runs like a raped ape. No matter what, that thing fires every time, has excellent get up and go, and what is really nice, is VERY EASY TO WORK ON!
As you can tell, I am frustrated as all get out. I think it is time for a beer.
