No Power

[cuddie01]

I have a 1987 Sea Sprite with a 4.3 that I put a 1990 s10 block and heads in and I cannot get it to run correctly has all new ignition parts and overhauled carb. low rpms it runs but tach goes to 3or 4 thousand rps going about 2000 and engine just starts running like a car with cat converter plugged, disconnected tach and runs better got it to go about 15 on the speedo before that would not even register, put a new electric fuel pump on and filter checked advance for sticking, has got me going crazy cannot figure out whats going on.

 

[Bondo]

Re: No Power

I have a 1987 Sea Sprite with a 4.3 that I put a 1990 s10 block and heads in and I cannot get it to run correctly has all new ignition parts and overhauled carb. low rpms it runs but tach goes to 3or 4 thousand rps going about 2000 and engine just starts running like a car with cat converter plugged, disconnected tach and runs better got it to go about 15 on the speedo before that would not even register, put a new electric fuel pump on and filter checked advance for sticking, has got me going crazy cannot figure out whats going on.

Ayuh,.... New parts, but is it "In Tune",..??

What's the timing,..?? Dwell,..?? Plugs,..??

How bad was the carb, on tear down,..??

What's the compression of this motor,..??

 

[cuddie01]

Re: No Power

Ayuh,.... New parts, but is it "In Tune",..??

What's the timing,..?? Dwell,..?? Plugs,..??

How bad was the carb, on tear down,..??

What's the compression of this motor,..??

timing is 8 degrees plugs are .035 carb was not bad at all , just did it because I had to buy a kit to get carb base gasket when motor was changed , compression is 125 on all cylinders, points are gapped at .020 I do not have a dwell meter but if gap is correct it should be close.

 

[Levinz11]

Re: No Power

If disconnecting the tach changes things...I would look at the connections at the coil. How many volts is the coil getting while running?

Since you say it runs "like a car with a plugged cat" could the flapper ion the exhaust be stuck or broken?

 

[cuddie01]

Re: No Power

I got to thinking, I put a car engine in and I'm pretty sure that the tach runs off #1 cyl in a car I checked the tach and it was set on #3 I changed it and it seems to be better but I have to get it on the water, any thoughts on this?

 

[Scott Danforth]

Re: No Power

the tach runs off of the coil no mater which cylinder is firing. it takes the total number of pulses, and then converts that to an electrical voltage to drive a simple meter. the tach is where you change from 4 to 6 to 8 cylinders, etc.

please describe your #1 and #3 cylinder issue. are you trying to time the engine off of #3 cylinder?

 

[Howard Sterndrive]

Re: No Power

I got to thinking, I put a car engine in and I'm pretty sure that the tach runs off #1 cyl in a car I checked the tach and it was set on #3 I changed it and it seems to be better but I have to get it on the water, any thoughts on this?

that switch on the back of the tach is used to set it for 4 cylinder, 6 cylinder or 8 cylinder and sometimes 2 cyl and 2 stroke or 4 stroke.
If it was accurate with the old motor, leave it at the setting it was on.

If it wasn't accurate, consult the tach manufacturer as there is no standard for those switch numbering systems