Dodged Another Bullit

[bobk]

You may remember when we got to Florida last fall we had a transom soot issue. The local DD mech replaced all six injectors on the port engine and it improved, but didn't return to normal.

I just had my local guy check that engine and he found all the injectors were set wrong, about .030" retarded. He tuned everything and I then asked him to check the starboard engine which he had rebuilt 1860 hours ago and he found the modulator was not opening completely (corrosion) and he fixed that then checked all the valves and injectors. They were mostly good, but he found one injector rocker had a bad bearing or bushing (probably wrong term). It was warn so bad that the mech did not thing it would have made it back to Florida. The consequence would have been parts flying around under the rocker cover. Whew. I didn't realize these DD's needed to be tuned every 1000 hours.

Bobk

 

[kelpy]

Tune them up once a year regardless of hours run.

 

[MikeP]

Tune them up once a year regardless of hours run.

Oh no! I guess I have a bunch of tune ups to do to catch up!

 

[dottieshusband]

I'll bite...what is the "modulator"?

 

[rsmith]

I'll bite...what is the "modulator"?

Their nothing but trouble I threw mine away years ago

 

[dottieshusband]

I'm pretty sure it's got something to do with the Flux Capacitor. Pretty sure

 

[Avenger]

I'll bite...what is the "modulator"?

I thought they were the guys that ran the forum.

Their nothing but trouble I threw mine away years ago

Well there you go.

 

[Freeebird]

I'm pretty sure it's got something to do with the Flux Capacitor. Pretty sure

It does. Keeps it from getting fluxed up and over warping the time and space continuum.

 

[jim rosenthal]

If they throw away the modulators, does that mean I don't have to do this anymore?

 

[Avenger]

Only if you can get them to throw away the super-modulators too.

 

[dottieshusband]

I think I need to call Bobk's mechanic as well. I suspect I'm 30% retarded also! Hopefully he can fix it. Ron White told me you can't fix what I have!

 

[Avenger]

Okay, you've suffered enough. It's a boost compensator. Basically it delays fuel delivery until the turbocharger develops enough manifold pressure to burn the fuel surplus to what a naturally aspirated engine can burn.

 

[dottieshusband]

Okay, you've suffered enough. It's a boost compensator. Basically it delays fuel delivery until the turbocharger develops enough manifold pressure to burn the fuel surplus to what a naturally aspirated engine can burn.

Is that what the throttle delay piston is? I could see that it dampened the action of the rack, but no real idea why.

 

[Avenger]

On a DD, yes. Most engines use an aneroid that references actual manifold pressure.