How do I remove a distributor rotor on 5.7 Mercruiser motor

[ted4420]

I want to remove the distributor sensor on a 5.7 Mercruiser. I have tested it and it showed it is open. No resistance. The engine starts and dies in 10 -60seconds. I can't remove the rotor. Please help! Ted

 

[Bt Doctur]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

If it was open the motor would not run at all.
Are you sure it`s not the pressure switch for the elec fuel pump.

 

[jtybt]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

Type of ignition system would help, too. I won't ASSume you have a points type distributor.

 

[searay3]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

Merc glued on the rotors. Maybe someone else has as well. You will have to either heat it or bust it. I would bust it and replace it, no glue.

 

[Don S]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

How do I remove a distributor rotor on 5.7 Mercruiser motor

--------------------------------------------------------------------------------

I want to remove the distributor sensor on a 5.7 Mercruiser. I have tested it and it showed it is open. No resistance. The engine starts and dies in 10 -60seconds. I can't remove the rotor. Please help! Ted

In your title you say rotor, in the post you say sensor. Which is it????

Mercruiser has used 5.7 engines since 1969. They are different in many ways from what we have in 2009.
So how about some info. Model numbers, serial numbers, year, ignition type, mechanical or electric fuel pump, etc. etc. ............

 

[ted4420]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

It has a mechanical fuel pump. While testing for spark the sensor tab was in between the sensor uprights. I put a spark plug in the coil wire and grounded it. I turned the ign. on and had constant spark at the test spark plug. Not a strong spark. I have sprayed a lite mist of starter fluid in the carb. while it was dieing and it still dies. When it is cold I can start the engine and stop the engine several times within a 30 second period. After that it gets harder to start. I have used a ohm meter and according to the flow chart I should have under 100 ohms. There isn't a reading. It also has constant spark when the red and white wire from the dist. is disconnected and the rotor interrupter plate is blocking the sensor. I will get the mo. number and the serial number tommorrow. Thanks. Ted

 

[Don S]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

ONE MORE TIME

Mercruiser has used 5.7 engines since 1969. They are different in many ways from what we have in 2009.
So how about some info. Model numbers, serial numbers, year,

 

[ted4420]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

This boat is a 1996 Capri 2050 SS. I can't find the serial number above the starter. I have the numbers off of the Mercury Marine operator & maintenance manual. It has a large K followed by these numbers on a sticker on the operators manual 4-57B100K
0K008446 Thanks, Ted

 

[Don S]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

OK, you have a 1997 engine, with Thunderbolt IV ignition.

I have used a ohm meter and according to the flow chart I should have under 100 ohms.

What chart did you get this from, and what are you testing? The sensor in the distributor?

Did you get the rotor off yet?

 

[ted4420]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

I am using the chart in the Mercruiser manual number 24 (1998-2002 the closest I could find) manual was down loadded from this site on page 1C-9 Testing Thunderbolt V Ignition System Flow chart and page 4B-21 ignition sensor testing. I have not removed the rotor or the sensor.

 

[ted4420]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

Any ideas? Ted

 

[Don S]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

Great, you used a Thunderbolt V troubleshooting chart to test a Thunderbolt IV ignition.
Download manual #17 and go to page 1C-8 for the proper chart.

 

[ted4420]

Re: How do I remove a distributor rotor on 5.7 Mercruiser motor

Thanks Don, I will try the new chart tomorrow. Ted